WO2018210453A1 - Device and method for the spectral control of a direct voltage converter - Google Patents

Abstract

The present invention relates to a method for controlling a power electronics unit for a vehicle, wherein, in a modulator of the power electronics unit, a switching state of the power electronics unit is selected from a number of possible switching states of the power electronics unit, as a factor of at least one request, to be provided in advance, for spectral properties of an error signal of an output voltage of the power electronics unit, and is adjusted in the power electronics unit.

Description

 Device and method for the spectral control of a

 DC-DC converter

The present invention relates to a method for controlling a

DC-DC converter and a suitable for carrying out the method presented modulator.

When using power electronics for the conversion of voltages or control of currents, for example. Between different on-board networks in land and water vehicles are covered by a respective power electronics

Power semiconductors connected at high frequency to map different states of power electronics. Due to the switching of the power semiconductors, the power electronics generates an error signal that can interact in frequency with other electrical devices, such as. A radio receiver, whereby noise or interference effects can occur. Particularly in the case of controllers of respective power semiconductors by means of pulse width modulators, harmonic harmonics often occur which affect other electrical devices as error signals. In order to investigate an influence of circuit-related spectral changes of

 To reduce power electronics, methods are described in the prior art in which a clocking of a modulator for switching respective power semiconductors of respective power electronics is changed. US 2001 0015 904 A1 discloses a method for reducing switching losses when switching power semiconductors

Power electronics disclosed. There are control signals for each

Power semiconductor determined as a function of voltages of respective motor phases. The US-American document US 2003 0174 081 AI discloses an inverter with a switching module for controlling respective power semiconductors of the inverter.

The US-American document US 2005 0254 265 AI is a method for controlling an output voltage of a voltage converter, which converts DC voltage into an output voltage predetermined by a control unit

remove.

A frequency divider and a method for frequency broadening a spectrum of a power converter, in which an additional signal is modulated onto an original clock frequency, can be found in the US-American publication US 2009 0033 374 AI.

A pulse width modulator based on a sigma-delta modulator is disclosed in US Pat. No. 5,901,176A.

In US Pat. No. 6,559,698 Bl, a circuit for controlling a clock rate based on a signal provided by an oscillator is disclosed.

Against this background, it is an object of the present invention to provide a means for controlling an error signal generated by power electronics

Maintaining a clock rate for switching respective power semiconductors

Power electronics provide.

It is a method for controlling a power electronics, for example, for a vehicle, presented in which, while maintaining a current clock rate of

Power electronics, a switching state of the power electronics from a number of possible switching states of the power electronics in response to at least one requirement to be provided in advance to spectral characteristics of an error signal Output voltage of the power electronics is selected and adjusted in the power electronics.

For the purposes of this invention, the clock rate is the rate at which calculations are made for the selection of the next switching state. The clock is preferably generated and preset by a clock, for example an electronic quartz. Alternatively, the clock can also from an existing clock via a

voltage controlled oscillator (VCO) or a clock divider or clock multiplier as are known to those skilled in the art. In

For example, the clock rate may serve as the clock of an integrated circuit or an iteration rate of an integrated circuit routine that implements the clock rate

Implemented control method according to the invention. The control method is preferably performed within one clock period or a predetermined multiple of a clock period and repeated at a regular repetition rate according to said clock.

The present invention particularly relates to power electronics

DC converter, which transfers electrical energy between at least two electrical connection pairs, preferably with different electrical voltages, wherein the electrical voltages of the electrical

 Connection pairs are DC voltages. DC-DC converters are known in large numbers in the prior art. Examples can also be found in the scientific literature [D. Schroeder. Power electronic circuits. 3rd edition, Springer, Berlin, 2012; ISBN 978-3-642-30103-2. and R.W. Erickson, D.

Maksimovic. Fundamentals of Power Electronics. 2nd edition, Springer, Berlin, 2001; ISBN 978-0-792-37270-7]. DC voltages within the meaning of the invention do not change their Spannungspolarität outside of a fault. Terminal pairs are also often referred to in the literature as inputs or outputs and respective associated voltages as input voltages or output voltages. In general, such terminal pairs are referred to as outputs whose voltages or currents, consequently as Output voltages or output currents referred to be regulated by a regulation to a predetermined target condition, for example, a target value out.

A control loop in the sense of the invention minimizes the absolute value of at least one associated error signal. In the present case, the error signal is preferably formed from the deviation of the frequency spectrum of at least one electrical voltage of at least one electrical connection pair to a predetermined target spectrum. The target spectrum is preferably given as a function of the frequency or as a table consisting of a finite number of pairs of discrete frequencies and associated values of the target spectrum at the corresponding frequency.

Embodiments result from the description and the dependent claims.

The presented method is used in particular for controlling or controlling a

Power electronics such that spectral properties, d. H. Amplitudes of respective frequencies, an output voltage or an error signal of the output voltage of the power electronics are adjusted according to a predetermined requirement. For this purpose, it is provided in particular that in a respective spectrum of a

Error signal, d. H. a distortion of the output voltage of the power electronics, which arises or by a change of switching states of the power electronics, at least one spectral gap is generated. Such gaps are typical, for example, notch and band-stop filter, as they are particularly in the low-power

Signal electronics are used, and correspond to greatly reduced amplitudes in a respective selected frequency range.

In the context of the presented invention, spectral properties in particular include amplitudes of a respective frequency spectrum of an error signal

To understand output voltage of a respective power electronics. Since the amplitudes of the frequency spectrum of the output voltage of the error signal of the power electronics in response to changes of switching states of the Changing power semiconductors of the power electronics, spectral properties and amplitudes of a frequency spectrum of an error signal are more relevant

Power semiconductors to understand the power electronics. Under a modulator, in the context of the present invention, a module for controlling switching times and timing sequences and switching sequences is more specific

Power semiconductors to understand a power electronics.

Using the presented method, it is also possible to provide the spectral properties of a respective power electronics or respective ones

 Power semiconductors of the power electronics adapt that is selected from the number of possible switching states of the power electronics that switching state that changes a spectrum of the error signal of the output voltage of the power electronics compared to a current switching state of the power electronics such that a selected range attenuated by a certain factor, d. H. is reduced in amplitude and, as a result, an influence of corresponding frequencies of the selected range is reduced to other electronic devices, in particular minimized. In order to damp or minimize an influence of respective frequencies of an error signal of an output voltage of a power electronics on other electronic devices, it is especially provided that starting from a number of past switching states of the power electronics, for a number of current and / or future switching states of the power electronics, a frequency spectrum of corresponding error signal is calculated or simulated. Starting from the simulated

Frequency spectra of the number of switching states can that switching state of

Power electronics are selected that best meets a respective requirement, that causes an error signal of an output voltage of the power electronics, which corresponds in its spectral characteristics of the requirement or shows a minimum deviation from the requirement of all alternative switching states. As soon as the switching state which optimally fulfills the respective requirement is established, the power electronics can be adjusted accordingly, ie the respective power semiconductors of the power electronics can be switched accordingly, whereby an average switching rate of the power semiconductors is adjusted simultaneously.

In particular, in simulations of possible switching states in several successive time steps in the future, sequences of switching states can be simulated and calculated. The method preferably tests in this form all combinations of the switching states for the directly following clock period with the switching states of the following clock period and a predetermined number of further subsequent clock periods in order to determine that sequence of switching states for a certain number of future clock periods at the end of the last of these clock periods the best result in the sense of the invention provides. In this case, the method can transmit the entire sequence to the switches for correspondingly assuming the switching states and thus carry them out in order to calculate the next sequence for then future clock periods only at the end of the sequence. Preferably, however, only a portion of the sequence, more preferably only the first switching state of the determined sequence is transmitted to the switches and implemented in the switches and discarded at the end of this part of the sequence, the remaining part of the sequence and the procedure described repeated, d. H. a completely new optimal sequence from the combination of all future possible switching states determined and again transmitted only a part of the sequence to the switch. The presented method makes it possible, by selecting switching states of the power electronics which are adapted to respective requirements, to correspondingly adapt error signals generated by a power electronics or of respective spectral properties of the error signals of an output voltage

Power electronics, even without a system clock of a control of

Power electronics must be changed or modulated. In one possible embodiment of the presented method, it is provided that the at least one request is selected as a function of a current position of the vehicle.

As requirements for electrical equipment, such as CISPR limits in

Dependence on country standards, d. H. can change depending on a current position of a respective vehicle, is provided in an embodiment, respective

Requirements for a frequency spectrum of an error signal of a switching state of a power electronics to be selected as a function of a current position of the vehicle, which is determined, for example. By means of a GPS sensor to select.

It is also conceivable that the respective requirements are dynamically adapted to changes of respective third-party devices, such as, for example, to a radio station tuned to a radio receiver. For this purpose, for example. With a frequency band set on the radio station, d. H. according to a current one

Setting the radio station changing, spectral gaps in a frequency spectrum of an error signal of an output voltage of each power electronics can be used as a basis for selecting respective requirements. This means that switching states of power electronics are selected as a function of a requirement that changes dynamically, for example, according to a currently set radio station or according to a current search window of a radio receiver.

In a further possible embodiment of the presented method, it is provided that the at least one request depends on at least one

Vehicle parameters of the vehicle is selected.

In addition to changes in third-party devices, such as radio receivers, changes in vehicle parameters, such as a speed, can be used to select or change a respective requirement. In a further possible embodiment of the presented method, it is provided that the at least one request is predetermined by a device encompassed by the vehicle and / or by a device assigned to a user.

Since a respective user associated devices such as smart phones are susceptible to interference, is provided in an embodiment of the proposed method that respective requirements by a user assigned device itself or in combination with another device, such as a radio receiver of a respective vehicle, given or used to select respective requirements. Accordingly, a request may be made such that frequencies generated by power electronics that is a receive frequency band of the

Radio receiver of, for example, 101MhZ superimpose, d. H. Frequencies in the range of 90MhZ to HOMhZ, show the lowest possible amplitudes.

In a further possible embodiment of the presented method, it is provided that all possible switching states of the power electronics are simulated and checked for their influence on a change of a frequency spectrum of an error signal in a predetermined time range of the at least one power semiconductor, wherein that switching state from the simulated switching states for conversion into the power electronics is selected and adjusted in the power electronics, one of the at least one request closest to the change

Frequency spectrum causes. In order to select a switching state of power electronics to be set at a respective power electronics from a number of simulated switching states, it is provided that all potentially available switching states are simulated and correspondingly adjusted by means of an adjustment of spectral characteristics of error signals

Output voltages of the power electronics and a predetermined requirement that switching state selected from the simulated switching states and in the Power electronics is set, which meets the requirements in the best possible way, that causes an output voltage to the power electronics, which meets the requirements in the best possible way. To simulate all available switching states of a power electronics respective power semiconductors in all possible switching states and in all

Combinations are considered with all other power semiconductors of a power electronics. A switching state of a power electronics indicates in particular a state of all power semiconductors of the corresponding power electronics.

In a further possible embodiment of the presented method, it is provided that the error signal of each simulated switching state of the power electronics is pre-processed by means of a sigma-delta modulation in order to determine a suitability of a respective switching state for the fulfillment of the at least one request, wherein as an integrator element the sigma Delta Modulation an exponentially decreasing window function is chosen to have an influence of more recent ones

Switching operations or switching states of the at least one power electronics to reduce the change in the error signal of the power electronics and in particular to suppress vibrations in the error signal.

By means of an exponentially decreasing window function as an integrator element of a sigma-delta modulation, it is possible to reduce an influence of past switching states of the power electronics and, as a result, a stability of the

Preprocessing increase and an influence of vibrations, often too

Disturbances in third-party devices lead to reduced sigma-delta modulation. The switching states of the power electronics are defined by the combination or interaction of the respective switching states of the individual power semiconductors of the power electronics. To illustrate this approach, the integrator element can be interpreted as a filter that weights the error signal to form a spectral pattern that attenuates the values of amplitudes of selected frequencies, such as those of high frequencies. In this case, the filter can in particular correspond to a target spectrum according to a respective requirement, wherein the penalty term is chosen such that respective frequencies are attenuated such that a correspondingly filtered spectrum approaches the target spectrum as best as possible, for example, by minimizing vibrations in the error signal. In a further possible embodiment of the proposed method, it is provided that, in the event that multiple requirements are specified, a target spectrum is determined by means of at least one predetermined weighting factor, which uses as default for selecting a respective switching state of the power electronics from the possible simulated switching states of the power electronics becomes.

By means of one or more weighting factors, different or even contradictory requirements can be considered simultaneously, as shown by way of example by equation (1). The two requirements "minimal switching losses" and "high accuracy", which usually behave in opposite directions, are determined by means of the

Weighting factors K and λ weighted so that both requirements can be considered together or at the same time in the selection of a respective switching state of a power electronics.

In this case, ε _{1 <2 stands} for a spectral deviation or for an error signal (see equation (2)), λ and K for weighting factors or compensation parameters, by means of which balancing between respective requirements and θ _{1 <2} for a density of respective ones

Switching actions that correspond to a density of respective switching losses, and S (k + 1) for the next selected switching state, wherein for a DC-DC converter S ε {0,1} -S described in the context of this invention, a numerical representation of the switching states that on the temporally following switching state of a respective

Dabei steht F(Ü>) für ein frequenztransformiertes, d. h. insbesondere Fouriertransformiertes quantifiziertes Ausgangssignal, Sp^*(a>) für ein Zielspektrum des Indicate power electronics. Furthermore, equation (2) applies to calculate ε _{1 <2} :

F (Ü>) stands for a frequency-transformed, ie in particular Fourier-transformed, quantified output signal Sp ^* (a>) for a target spectrum of the

Error signal, and G (Ü>) for a desired output profile.

In a further possible embodiment of the presented method it is provided that the error signal of the at least one power semiconductor by means of a

Filter function is pre-processed to determine the suitability of each switching state to meet the at least one request.

To a respective optimal or one of a particular request most suitable switching state of a number of simulated switching states of

To determine power electronics, it is provided to examine the error signals of the simulated switching states with regard to their spectral properties and to select them with regard to the respective requirement. To assess the suitability of a respective switching state of a power electronics to meet the respective requirement is provided in an embodiment that the error signals of the simulated switching states of the power electronics are pre-processed by means of a filter function. As a filter function, for example, a bandpass or bandwidth filter or a notch filter (notch filter or frequency cut filter) can be selected, which approximates a frequency spectrum of an error signal of a respective switching state of a power electronics to a specified by the requirement target by, for example, a certain frequency range in its amplitude is lowered. By preprocessing the error signals of all simulated switching states of power electronics, a respective most suitable switching state can be identified and selected for adjustment to a respective power electronics. In a further possible embodiment of the presented method, it is provided that a cut-off function, which is inversely proportional to high frequencies at respective amplitudes of a number of selected frequencies, is selected as the filter function. By means of a high frequency or corresponding amplitudes of the high

Frequencies inversely proportional cut-off function, it is possible a

Filter characteristic, as is typical for a bandpass. This means that by means of the cutoff function falling inversely proportional to high frequencies, an edge of a spectrum of an error signal of a power semiconductor can be cut off or greatly reduced in its amplitude, so that influences of the high frequencies are minimized. By applying a cut-off function to a spectrum of an error signal, it is possible to "cut off" a given frequency range of the spectrum or to filter the spectrum in such a way that the predetermined frequency range is attenuated in its corresponding amplitudes.

In a further possible embodiment of the presented method, it is provided that selected values of the frequency spectrum are reduced in their amplitude below a predetermined threshold value by means of a mathematical function. In order for third-party devices, such as radio receivers of a vehicle disturbing frequencies when operating a power electronics, such as

To avoid voltage conversion between two on-board networks, is provided in an embodiment that selected frequencies or frequency ranges, for example, from 800 kHz to 850 kHz by means of a mathematical function, such as a

Filter function, damped, or reduced in their amplitude, ie weakened in intensity. Due to a weakening of selected frequency ranges in their intensity, so-called "spectral gaps" are created, which are chosen in particular such that they are placed in operating ranges of third-party devices in order to meet respective requirements of, for example, the third-party devices. By selective attenuation of selected frequencies, it is possible to select selected areas of a respective frequency spectrum of an error signal of a switching state of

Power electronics to filter or attenuate, so that disturbances in the third party devices can be reduced or completely avoided. It is also possible to filter or attenuate a plurality of regions in the respective frequency spectrum by means of the mathematical function, wherein respective regions can also be selected dynamically as a function of a current setting of at least one third device of the vehicle. In a further possible embodiment of the presented method, it is provided that an amplitude of 40 dB is selected as the threshold value.

Experience has shown that a threshold value of 40 dB has proved to be the threshold for attenuation of respective frequencies, since an intensity below this threshold significantly reduces an influence on third-party devices.

Furthermore, the present invention relates to a modulator for power electronics, wherein the modulator comprises at least one control unit which is configured, a switching state of the power electronics in response to a comparison of predetermined by at least one specification spectral requirements and respective frequency spectra of error signals of an output voltage of the power electronics, each corresponding to a simulated switching state of the power electronics to select and with constant timing of respective switching rates of

Adjust power electronics from the number of simulated switching states on the power electronics.

The switching state of the power electronics is thereby encompassed by an interaction of respective switching states of the power electronics

Power semiconductors defined. The power electronics comprise at least one, usually a plurality of power semiconductors. The presented modulator is used in particular for carrying out the presented method. In a further possible embodiment of the presented method is provided for controlling a time average of the output voltage of

Gleichspannungswandlers the presented method with voltage or

Current control methods (in particular P, PI, and PID control, deadbeat control, sliding mode control, LQR control) to combine. In this case, the presented method is used as the inner control loop of a cascaded control structure, while the voltage regulation forms the outer control loop.

In this case, an offset can be subtracted from the calculated values of the numerical representation of the switching states in order to achieve the desired time average of the output signal or of the output voltage. As numerical

 Representation of the switching states in the context of the invention, the binary symbols (for example, {0, 1}) as a state description of the state of an electrical switch (open and conductive) as numerical numerical values considered and processed, for example, numerically to describe intermediate stages between the states or mathematical operations be executed, which require a more or less continuous or dense value range. Should z. B. in a buck converter one

Output voltage of half the amplitude of the input voltage can be set, calculated the method presented by means of the numerical representation of the switching states S ε {-0.5, 0.5} the output signal, while retaining all

featured benefits. A ratio of 0.5 between the input and output voltages is enforced by the external control.

In a possible embodiment of the presented modulator is provided that the control unit is further configured to be in the frequency spectrum by means of mathematical function depending on the at least one request to generate spectral gaps.

By generating "spectral gaps", i. H. an attenuation of selected frequencies in a frequency spectrum of an error signal of a switching state of a

Power electronics, it is possible to operate a respective power electronics so that respective third-party devices of a vehicle or a user are not affected in their operation. Further advantages and embodiments will become apparent from the description and the accompanying drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

The invention is schematically illustrated by means of embodiments in the drawings and will be described schematically and in detail with reference to the drawings.

FIG. 1 shows a possible embodiment of the presented method, in which a specification for carrying out the presented method is selected as a function of a current position of a respective vehicle.

FIG. 2 shows a schematic representation of a sequence of a possible embodiment of the presented method. Figure 3 shows effects of variously chosen weighting factors in the

Calculation of a frequency spectrum of an error signal of an output voltage of a power electronics according to a possible embodiment of the presented method. FIG. 4 shows effects of a filter function for superimposing a

Frequency spectrum of an error signal of an output voltage of

Power electronics according to another possible embodiment of the presented method. FIG. 5 shows effects of a further filter function for superimposing a

Frequency spectrum of an error signal of an output voltage of

Power electronics according to yet another possible embodiment of the

presented procedure. FIG. 6 shows effects of a further filter function for superimposing a

Frequency spectrum of an error signal of an output voltage of

Power electronics according to yet another embodiment of the proposed method for generating gaps in the frequency spectrum of a

Output voltage.

FIG. 7 illustrates an embodiment of the method according to the invention in which a spectral control is used in cascade within a control loop for regulating the voltage of a terminal pair. The voltage regulation can also be replaced or supplemented by a current regulation.

Figure 8 shows a schematic representation of a sequence of a possible embodiment of the presented method for influencing a frequency spectrum of a

Output voltage of a power electronic switch. FIG. 9 shows a schematic illustration of a sequence of a possible embodiment of the presented method for minimizing the switching losses of a

power electronic switch. FIG. 10 shows a schematic illustration of a further possible embodiment of the presented method by a combination of the embodiments shown in FIG. 8 and FIG.

In Figure 1, a vehicle 1 is shown, which is a third party in the form of a

Radio receiver 3 and a power electronics for controlling an electric motor of the vehicle comprises.

Since the radio receiver 3 is set as a function of a current position of the vehicle in order to correspond, for example, to national specifications, the current position of the vehicle 1 is detected by means of a GPS system 5. By means of the current position of the vehicle 1, corresponding national specifications are queried from a database 7 and specifications are generated for an error signal of an output voltage of the power electronics. Depending on the specifications, a target value for a spectrum of the

Error signal of the output voltage of the power electronics generates. This target value or a corresponding target spectrum 9 is used as the output value for a comparison in which all possible switching states of the power electronics are simulated and analyzed for their spectral effects on the output voltage of the power electronics. This means that each frequency spectrum of an error signal of an output voltage generated according to a respective simulated switching state of a power electronics is compared with the target spectrum 9 and the

Switching state is selected from the number of simulated switching states, which causes an output voltage that corresponds to the target spectrum as best as possible. In order to meet respective requirements, the target spectrum 9 can in particular have spectral gaps in which the amplitudes of respective frequencies are particularly strongly damped. In the process illustrated in FIG. 2, setpoint values 21 are known from respective specified requirements and past values 23 from a history of switching states of power electronics. Based on the past values 23 all possible alternative switching states of the power electronics are in one

Alternate formation step 25 determined. For each switching state in the

Alternating step 25 detected switching states is independently determined a corresponding error signal in a step 27 or 27 'and in

Frequency transformation steps 28 and 29 or 28 'and 29', in which a Fourier transformation of a selected time range is calculated, examined for its spectral components. Of course, the

Frequency transformation steps 28 and 29 or 28 'and 29' are combined to a step 30 using short-term frequency analyzes, such as wavelets. On the respective frequency spectrums calculated by the frequency transformation steps 28 and 29 or 28 'and 29', selected mathematical functions such as filters and / or standard functions are applied in a step 31 or 31 'to judge their correspondence to respective requirements and in one

 Selection step 33 to select the switching state of the power electronics, which causes an output voltage of the power electronics, the best possible meets the requirements and this accordingly by means of a modulator, such as

Pulse width modulator in a control step 35 to adjust the power electronics. To assess whether a respective frequency spectrum optimally fulfills a respective requirement, for example, a difference between a spectrum corresponding to the requirement and a respective spectrum which is assigned to a specific switching state from the alternative switching states determined in step 25 can be calculated. A respective switching state of the power electronics is one or a plurality of configurations of switching states encompassed by the power electronics

Power semiconductors assigned. This means that a respective switching state of the power electronics is realized by a specific configuration of switching states of the individual power semiconductors of the power electronics. It is conceivable that there are several alternative configurations of switching states of the power semiconductor for realizing a switching state of the power electronics.

FIG. 3 shows a first spectrum 31 and a second spectrum 33, wherein the first spectrum 31 and the second spectrum 33 are each plotted in a diagram which is located on the abscissa over a frequency in the unit Hz and on the ordinate over one normalized relative amplitude extends.

The first spectrum 31 shows effects of differently chosen

Weighting factors on an equation, by means of which two requirements are taken into account simultaneously in the calculation of a spectrum of an error signal of an output voltage of a power electronics. By means of the weighting factors, factors of the equation according to the two requirements are adjusted such that a corresponding spectrum best suits the two requirements, i. H.

shows the lowest possible deviations from the target spectra given by the two requirements. In the present case, the first spectrum 31 shows the effects of the selection of small values in the determination of a first weighting factor, so that low frequencies, for example in a region 35 in comparison to higher ones

Frequencies in a range 37 are relatively strongly attenuated. Due to the influence of the second weighting factor, however, a relatively small number of outliers 39 occur in region 35, which could lead to disturbances in third-party devices.

The case that large values are chosen to determine the first weighting factor, so that low values of a respective interference signal tolerates or higher values the interference signal is attenuated, is represented by the second spectrum 33, which is attenuated especially at high frequencies, with individual very strong outliers 39 occur, which could have as interference on third party equipment. It has been found that one way of reducing the outliers 39 is to perform a number of simulation steps of switching states of the power electronics and, associated therewith, of respective switching states of the power semiconductors that are involved in the

 Calculation of the second spectrum 33 can be considered to increase. This means that a simulation of a large number of switching states, such as 2, 5, 10 or 100 in the future, reduces or minimizes outliers.

 10

 FIG. 4 shows a spectrum 43 which has been entered into a diagram which extends over the abscissa over a frequency in the unit Hz and on the ordinate above a normalized relative amplitude. By applying a filter function, an error signal underlying the spectrum 43 was processed in such a way that the spectrum 15 43 shows a strongly flattening edge region 45, by which respective interference frequencies can be filtered out or suppressed according to a respective requirement.

In Figure 5, a spectrum 51 is shown, which was plotted on a graph which is on the abscissa over a frequency in the unit Hz and on the ordinate over a

20 normalized relative amplitude extends. By applying a mathematical

 Filter function was a range 53 within the spectrum 51, attenuated at about 5000 Hz with a width of about 400 Hz to create a spectral gap in the spectrum 51, so that a third party that sensitive to interference in the range of 5000 Hz is operated without interference parallel to a correspondingly regulated power electronics

25 can be.

In Figure 6 spectrum 54 is shown, which shows the spectrum of a switching signal of a switch of a power electronics using an embodiment of the presented method, which was plotted on a graph that is on 30 of the abscissa over a frequency in the unit Hz and on the Ordinate over one normalized relative amplitude extends. By applying a precomputed mathematical filtering function, two regions 55 and 56 are simultaneously attenuated by the presented control method to produce two spectral gaps in the spectrum 54 such that a third device sensitive to spurious signals in these two regions operates smoothly in parallel with a correspondingly controlled one Power electronics can be operated.

In the process illustrated in FIG. 7, the presented method 60 is applied in a cascaded control to control the output voltage 62 of a

DC converter 61 to control using an outer control loop 59. In this case, the voltage error 64 is calculated by the output voltage 62 of the

DC-DC converter 61 is subtracted from the setpoint 57. From the

Voltage error 64 can thus be used to calculate the input to the voltage regulation method 63 (eg PI controller). The ratio of the voltage error 64 to

Input voltage is subtracted from the numerical representation of the switching states, and used as input to the external voltage regulator 63. The external voltage regulator 63 calculates the input of the present invention

Method 60. The presented method 60 calculates using a

Frequency transformation from this value, the optimal switching signals for controlling at least one switch of the power electronics 61st

In the process illustrated in FIG. 8, setpoints 58 are known by respective specified requirements and past values 70 from a history of switching states of power electronics. By means of the determination of all possible switching states of a power electronics 71 and 7, and their subtraction 65 from the setpoint signal, all possible future switching states of power electronics and the history of switching states of the power electronics with a temporally exponentially decaying window 66 are multiplied to the input signals as vectors for the

Frequency transformation 67 provide. The results of the frequency transformation 67 are compared with a target spectrum 68, resulting in an error signal in the Frequency range is calculated. From all possible switching states of the

Switching state determined with the most optimal for the application error signal in the frequency domain in step 69, and output as a switching signal 74 of a switch power electronics.

In the flow shown in FIG. 9, set values 58 are known by respective specified requirements and past values 70 from a history of switching states of power electronics. By means of the determination of all possible switching states of a power electronics 71 and 7, all possible future switching states of a power electronics and the history of switching states of the power electronics are evaluated to determine the number of switching operations in the examined time window for all possible future switching states in a step 72. Then, in a step 73, among all possible future switching states, the future switching state that is best in accordance with the predetermined specifications (eg, minimum number of switching states) is selected, and in step 75, a switching signal of a switch of power electronics output.

In the process illustrated in FIG. 10, setpoints 58 are known by respective specified requirements and past values 70 from a history of switching states of power electronics. The illustrated sequence combines the calculations of the processes shown in Figure 8 and Figure 9. Here, both the number of

Switching states in the examined time window as well as the error signal in

Frequency range of all possible switching states for all possible future ones

Switching states taken into account to calculate the selection of the future switching state of the power electronics. Here, the output signals compared with the target spectrum 68 in the frequency range of all possible future

Switching states and the number of switching states in the examined time window for all possible future switching states in a step 77 multiplied by a predefined weighting factor to calculate a weighted evaluation. Thereafter, in a step 78 for all possible future switching states the weighted calculations added to the overall rating of each possible

determine future switching state. These are compared, analogous to 69 and 73, by a predefined method 76 to determine the optimal future

To identify switching state. The optimum future switching state is passed on in step 79 to a switch of power electronics.

An embodiment of the present invention includes at least one integrated circuit, preferably a digital signal processor (DSP), a field programmable gate array (FPGA), or an application specific integrated circuit ASIC to implement the method. This embodiment preferably measures at least one electrical voltage on at least one electrical connection pair by means of at least one voltage measurement and converts the at least one signal of the at least one voltage measurement into digital values for the at least one integrated circuit by means of an analog-to-digital conversion. Preferably

For example, this embodiment implements a cascaded control in which, for example, a spectral control is embedded in a voltage control.

In a preferred embodiment, the invention further comprises at least one digital frequency transformation, preferably a discrete Fourier transformation. In particular, the at least one frequency transformation can transform at least one digital voltage signal into a frequency range directly or indirectly after further mathematical operations. Furthermore, this embodiment

include at least one shift register. The at least one shift register preferably stores past power electronics switching states, wherein the oldest value in the memory may be cleared in each timing step when a new value is added. The output of the switching states, which were identified as optimal due to the simulation of the possible switching states, can take place by means of at least one digital output of the at least one integrated circuit. In addition to the at least one digital output, the embodiment preferably further comprises at least one gate driver which receives at least one signal of the at least one digital output and electrically amplifies this signal for at least one electronic switch.

In a further embodiment, the control cascade comprising at least one voltage regulation and at least one spectral regulation may further comprise at least two integrated circuits, at least one of which is integrated

Circuit voltage regulation comprising at least one analog-to-digital converter, at least one digital output for outputting switching states and at least one controller implemented and at least one integrated circuit spectral control comprising at least one frequency transformation, at least one

Shift register, at least one vector difference unit for calculating the difference between two vectors and at least one cumulative sum unit, which receives as input at least one vector and calculates the sum of the entries of the vector implemented. When calculating the difference of two vectors is preferably directly or indirectly after further mathematical operations, the

Vector difference between the spectra calculated from a simulated voltage and a target spectrum.

Claims

claims A method for controlling power electronics, wherein a switching state of the power electronics is selected from a number of possible switching states of the power electronics as a function of at least one requirement to be provided in advance spectral characteristics of an error signal of an output voltage of the power electronics and adjusted in the power electronics. 2. The method of claim 1, wherein the power electronics energy between at least two electrical connection pairs, each with different DC voltage transferred. 3. The method of claim 2, wherein the power electronics maintains a current clock of a modulator. 4. The method according to any one of the preceding claims, in which all possible Switching states of power electronics simulated and their influence on a Modification of a frequency spectrum of the error signal of the output voltage of the power electronics are checked in a predetermined time range, and wherein that switching state selected from the simulated switching states for implementation in the power electronics and adjusted in the power electronics, which meets the at least one request as best as possible. 5. The method according to claim 3 and 4, wherein all possible switching states of Power electronics for a next clock step of the modulator in the future simulated and checked for their influence on a change in a frequency spectrum of the error signal of the output voltage of the power electronics in a predetermined time range, and wherein the switching state of the simulated Switching states selected for implementation in power electronics and in the Power electronics is set, which meets the at least one requirement in the best possible way. 6. The method according to claim 3 and 4, wherein all possible sequences of Switching states of the power electronics for at least two successive next clock steps of the modulator simulated in the future and checked for their influence on a change in a frequency spectrum of the error signal of the output voltage of the power electronics in a predetermined time range, and wherein at least the earliest switching state of that sequence from the simulated switching states selected for implementation in power electronics and adjusted in the power electronics, which is the at least one requirement best possible fulfilled. 7. The method according to any one of claims 4 to 6, wherein the error signal of each simulated switching state of the power electronics by means of a sigma-delta modulation is pre-processed to a suitability of a respective switching state of To determine power electronics to meet the at least one request, as an integrator element of the sigma-delta modulation an exponentially decreasing Window function is selected to an influence of respective previous Switching states of the power electronics to reduce the change of the error signal and in particular to suppress vibrations. 8. The method according to any one of claims 4 to 7, wherein in the case that a plurality of requirements are given by means of at least one predetermined Weighting factor, a target spectrum is determined as the default for selecting a respective switching state of the power electronics from the possible simulated Switching states of the power electronics is used. 9. The method according to any one of claims 4 to 8, wherein the error signal of Output voltage of the power electronics pre-processed by a filter function is to determine a suitability of a respective switching state of the power electronics to meet the at least one request. 10. The method of claim 9, wherein the filter function has a frequency-dependent course and whose value at least one frequency at least the  Ten times the value of another frequency. 11. The method of claim 9, wherein selected values of the frequency spectrum by means of a mathematical function in amplitude below a predetermined 10 threshold can be reduced. 12. The method of claim 11, wherein an amplitude of 40 dB is selected as the threshold value. 13. The method according to claim 1 for controlling power electronics for a vehicle, wherein the at least one request is selected as a function of at least one vehicle parameter of a vehicle. 14. The method according to any one of claims 1 to 12 for controlling a power electronics 20 for a vehicle, wherein the at least one request in dependence of  current position of the vehicle is selected. 15. The method according to any one of claims 1 to 12 for controlling a power electronics for a vehicle, wherein the at least one request by one of the vehicle 25 and / or predetermined by a device assigned to a user. 16. The method of claim 2, wherein for generating the error signal, the result of a subtraction of the ratio of a target value of the electrical voltage of at least one first electrical connection pair to the electrical voltage at least one second electrical connection pair is used by a numerical representation of the switching states. 17. The method of claim 2, wherein an electrical voltage of at least one electrical connection pair is set via a value of a filter function at a predetermined frequency. 18. The method according to claim 17, wherein the predetermined frequency of the Filter function for adjusting the electrical voltage of the at least one electrical connection pair is less than 1 Hz. 19. Modulator for power electronics, wherein the modulator at least one Controlling device configured to a switching state of Power electronics from a number of simulated switching states depending on a comparison of at least one requirement to be provided in advance spectral characteristics (9) of an error signal of an output voltage of the power electronics with respective frequency spectra (31, 33, 43, 51) of error signals Select output voltage of the power electronics, each corresponding to a simulated switching state of the power electronics, and set at constant clock of the modulator to the power electronics. 20. The modulator of claim 19, wherein the power electronics comprises at least two pairs of electrical terminals whose respective associated electrical voltages are mutually different DC voltages. 21. The modulator of claim 19, wherein the control unit is further configured to generate spectral gaps in a respective frequency spectrum by means of at least one mathematical function as a function of the at least one request. 22. The modulator of claim 19, 20 or 21, wherein the control unit comprises at least one electric clock with a constant clock frequency. 23. The modulator of claim 22, wherein the at least one electrical clock 5 comprises at least one electronic quartz. 24. The modulator of claim 22, wherein the modulator comprises at least one digital frequency transformer. 10 25. Computer program product with a computer-readable medium on which  at least one target spectrum is stored, and a computer program stored on the computer-readable medium with program code means, which are designed to run on the computer program on a computer  Run a control loop, the frequency spectrum of at least one electrical 15 sets voltage of at least one electrical connection pair to the target spectrum, wherein the at least one electrical voltage is a DC voltage.