SU902195A1 - Method of adjusting automatic regulator for three-phase synchronous machine - Google Patents

Description

(54) METHOD OF ADJUSTING THE AUTOMATIC CONTROLLER FOR THREE-PHASE SYNCHRONOUS MACHINE

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The invention relates to electrical engineering and can be used in setting up equipment for controlling the excitation current of electric machines, preferably automatic controllers for controlling thyristor excitation of synchronous machines.

A known method for setting up automatic regulators, in which the correspondence of current and voltage signal sensors to automatic field current regulators is determined either by visual inspection of the conductors connecting the signal sensors and the control circuit inputs, or by their individual dialing while the electric machine 1 is not working.

The disadvantage of this method is low productivity and the need for sufficiently qualified service personnel. In addition, in some cases, this method is practically inapplicable, for example, when the premises are heavily loaded or when the signal sensors are significantly removed from the control circuit.

Closest to the invention is a method for setting up an automatic excitation controller of three-phase synchronous machines, in which the synchronous machine is turned on in the network, excited by its excitation current, loaded, the parameters of the output signals of the current transducers and the stator voltage are measured, and compared with each other A certain combination of signals is connected to the corresponding pair of said transducers to the inputs of the excitation controller.

When setting up regulators for this way. The appropriate phase combination is determined with the aid of an electron oscilloscope 2.

The disadvantage of this method is the need for appropriate personnel qualifications and the availability of an electronic oscilloscope. In the practice of regulators, these conditions are not always met, for example, due to the considerable remoteness of the operation of synchronous machines from the maintenance bases (drilling rigs, gas and oil pumping stations).

% t. d.).

The purpose of the invention is to simplify the setting.

Claims (1)

The goal is achieved by prior to measuring the signals at the output of the converters the load of the machine is set reactive, and the excitation current is increased above the nominal no-load current, and then alternately measure parameters proportional to the amplitude of the output signals of the current converters of one of the phases and voltage converters of all phases the stator, determine the arithmetic sum of each pair of values of these parameters, combining in pairs the signal of the current converter with each signal the voltage generator, then alternately electrically summing the output signals of each pair of transducers, measuring the value of a parameter proportional to the amplitude of the electric sum signal, comparing the results of arithmetic and electrical summations and determining the required combination of current transducers and stator voltage, after which the specified connection operation is performed. FIG. 1 is a schematic diagram of an excitation system coupled to a phase mismatch meter, which allows the indicated operations to be performed; in fig. 2 is a vector diagram of currents and voltages of a synchronous machine, corresponding to the measurement mode. The excitation system consists of a synchronous machine 1 (Fig. 1), the excitation winding of which is connected to the thyristor converter 2, the control input of which is connected to the output of the control unit 3, to the inputs of which current converters 4 and 5 and voltage converters 6 and 7 are connected. The phase mismatch meter for the stator current and voltage contains matching resistors 8 and 9, which are connected to the outputs of the signal converters and the switch 10 of the measurement modes. A switch of 11 phasing modes is installed in the stator voltage converter circuit. To measure the output parameters of the signal converters, the output of the switch U is connected to a measuring device (ammeter) 12. As shown in the diagram of currents and voltages (Fig. 2), when the synchronous machine is operating in an overexcited (capacitive) mode, the linear voltage vector and the conjugate phase current vector, for example, UAB and c. match in phase. On this principle, a phase mismatch meter was built, which allowed modeling the voltage and current diagram by simple means. The setting of the automatic controller is as follows. A synchronous machine is turned on in the network without an active load, it is excited by its excitation current, the value of which is more than the nominal value of the no-load current. When the position of the switch 11, corresponding to FIG. 1, measurements are made of the parameters of the output signals by an ammeter of 12 effective values of the current signal (switch 10 is set to the 10-2 position) and the sum signal (at the 10-3 position). If the sum of the readings of ammeter 12 at position 10-1 and 10-2 of switch 10 is equal to that of ammeter 12 at position 10-3, then the initial voltage and current vectors are uniquely determined, and therefore the corresponding pair of transducers is determined. If this condition is not observed, switch 11 must be moved to the next position and the phase matching condition checked. This operation is repeated until the condition of equality of signals 4 + ЗЗ + is satisfied. :) Setting up the automatic controller according to the proposed method simplifies the operation of phasing the current and voltage of the stator and eliminates the use of an electronic oscilloscope, which leads to a reduction in the cost of entering the controller in operation. The method of setting up an automatic controller for a three-phase synchronous machine, in which a synchronous machine is turned on in a network, is excited by its excitation current, is loaded, the parameters of the output signals of current transformers and stator voltage are measured, compared with each other and with a certain combination of signals a pair of said converters to the inputs of the automatic controller, characterized in that, in order to simplify the adjustment, before measuring signals at the output of the pr the masters load the reactive one and set the excitation current above the rated no-load current, then alternately measure parameters proportional to the amplitude of the output signals of the current transducers and voltage transducers of all stator phases, determine the arithmetic sum of each pair of values of these parameters, combining the current converter signal in pairs with each voltage converter signal, then alternately electrically summing in The output signals of each pair of transducers measure the value of the parameter proportional to the amplitude of the electric sum signal, compare the results of arithmetic and electrical summations and determine the required combination of current transducers and stator voltage by matching the values of the sum signal of one of the pairs. connection operation. Sources of information taken into account in the examination