DE102009011757A1 - Controller for small power grids for use as interface between one or more current generators and individual electricity consumers, comprises energy distributor for branching of electrical power from feeder line to multiple consumer lines - Google Patents

Abstract

A small power supply control unit for use as an interface between one or more power generators (2) and individual power consumers (7) with a power distributor (5) for branching the electrical power from a feeder line (3) of the power generator (2) or the small network on several consumer lines (6) to improve the optimal use of the electrical energy provided, it is proposed that the power distributor (5) switching modules (8) for connecting or disconnecting the respective consumer line (6), wherein the switching module (8) of a control module (9) are switchable, that the control module (9) is connected to a sensor module (11) for detecting voltage and currents of the mains and that the control module (9) individual predetermined switching modules (8) in the sense of stabilizing at least one of the network module obtained from the sensor module (11), such as, for example, the mains frequency, being switched on or off e is formed.

Description

The The present invention relates to a control device for small power grids for use as an interface between a or multiple power generators and individual power consumers, with a power distributor for branching the electrical power from a supply line of the power generator or the small power grid on several consumer lines.

A generic control unit is from the WO 00/77527 A2 known. This is essentially used to determine the energy consumption of individual consumers and the shutdown of each consumer as soon as a prepaid amount of energy is consumed.

task The invention is a controller for small Electricity networks of the type mentioned above indicate the energy flow in the power grid according to supply and demand and possibly further requirements can control.

The Invention solves this problem in that the energy distributor Switching modules for connecting or disconnecting the respective consumer line, wherein the switching modules are switchable by a control module that the control module with a sensor module for detecting voltage and the electricity grid is connected and that the Control module individual predetermined switching modules in the sense of stabilization at least one network parameter obtained from the sensor module, such as For example, the network frequency formed on or off is.

Inselnetze are characterized in contrast to compound networks usually characterized that for their supply of electrical energy one for cost reasons limited power plant capacity. Will more Power related as the power plants in the island grid at the same time can supply, or more energy than the power plants in over the period in question, that is how it is the power plants due to overload and set the Island network thus completely out of service. Often it spreads Among the electricity users dissatisfaction over the low Availability of electrical energy. As result come with electrical energy related economic Development processes in the community of users to a halt. This problem is solved by the invention in that it the Power grid in case of overload by switching off individual households Consumers, and thus the majority the electricity customers continue to be supplied with electrical energy can.

The Sensor module enables recognition of the overload case as an indicator, for example, the voltage drop, the current increase or preferably the drop in the grid frequency can be used can.

In a preferred embodiment, the control module a programmable microprocessor and a non-volatile Data storage on. This measure allows the Adaptation and change of strategies at any time Ensuring the quality of the power grid in dependence of different parameters. Furthermore, the storage of the determined and calculated data and parameters possible, for example, a later evaluation as a basis for further optimization strategies to be able to.

In a simple embodiment is provided that the Control module at a drop in the mains frequency below a predetermined Value is formed switching off one or more switching modules. The drop in the grid frequency shows the overload of the generator at. By switching off a switching module, the associated Load dropped and thus the overload of the generator reduced. Should the switching off of a switching module not yet incur the required increase in grid frequency, so the next switching module is switched off and immediately, until the grid frequency stabilizes.

The Invention will be in terms of limiting the grid frequency after above even improved by the control module over at a rising mains frequency a predetermined value switching on one or more switching modules is trained. By connecting the switching modules are additional Loads connected, which load the generator and thus the mains frequency reduce. This can be one for the generator or the other consumer harmful exceeding of the mains frequency and possibly an excessive increase in the mains voltage be prevented. Even if this measure is already through the connection of an ohmic resistance can be done is recommended, as an additional load, for example, a water pump to turn on, which promotes water into a storage tank, from where it is available for further use is maintained, for example, for power generation to cover short-term peak loads.

In a development of the invention, it is proposed that the switching modules each have a priority value assigned to them and that the control module takes into account its priority value when selecting the switching module to be connected or disconnected next. Less important consumers receive a lower priority value, and more important consumers a higher priority value. The strategy be is now, if necessary, always switch off the switched-on switching module with the lowest priority value next or, in the opposite case, always switch on the switched-off switching module with the highest priority value next. This ensures that the most important consumers are preferably supplied with energy.

In Development of the invention, the control unit comprises an overcurrent protection device and the control module is configured to be a switching module turns off when in the associated consumer line a predetermined Current is exceeded. This measure ensures that one agreed with the electricity customer Amperage is not exceeded and total the load on the network is limited. Furthermore, the consumer lines protected against overload.

The Invention is further improved by the control unit a Residual current device includes and the control module so is designed that it shuts off a switching module when in the associated consumer line fault currents occur.

In a preferred embodiment detects the control unit the apparent or active power consumed by a consumer and stores them, the control module configured in such a way is that when it exceeds the time averaged Apparent or active power over a predetermined value the associated switching module switches off. This will ensure that agreed with the power customer apparent or active power can not be permanently exceeded. This measure protects the capacity of the power plant.

By the measure that the control unit over a consumer line over time flowing electrical Energy recorded and the values for the total energy consumption of the associated power consumer stores, becomes a Consumption-friendly payment of electrical energy allows. In this case, the flowed through the respective consumer line electrical energy preferably by integration over the respective applied electric power are determined. The Values for the total energy consumption will be from time to time stored in the non-volatile memory. This is the total energy consumption for every electricity customer even after a power failure at any time available.

The Measure that the control module is that of a consumer line assigned switching module is configured shutdown, as soon as predetermined maximum value for the total energy consumption exceeded is, allows the sale of prepaid energy packages to the electricity customers. The maximum value to be specified here corresponds then the amount of energy purchased by the electricity customer.

The Invention can still be improved by the control unit has a prepayment module with the prepayments of the electricity customers are detectable and calculated according to an advance payment new maximum value for the one consumer power assigned Total energy consumption is storable. Such a prepayment module preferably contains a card reader for Smart cards or memory cards, which are located at a central point Pay a certain amount of energy with this amount of energy representing the data packet being "charged", then read out in the card reader of the prepayment module to be, with the maximum value assigned to the respective power customer for the total energy consumption by the prepaid amount of energy is increased.

In Another embodiment is provided that on the prepayment module further associated with the respective consumer line of a power customer Parameters such as the maximum apparent or active power or usage period selectable by the electricity customer and / or readable and storable.

If the control unit a display for displaying currently measured and / or stored parameters and / or consumption data can this data, for example, by a service technician directly on Device can be read without a reader, For example, a laptop would have to be connected.

If the credit of individual electricity customers can be displayed on the display, These electricity customers can easily over to inform their remaining balance.

With Advantage is provided that all network data and / or consumption data storable and to determine the quality of the power grid and / or for the purpose of determining the usage behavior of the electricity customers are available and displayable.

Around the data is easily retrievable and on other devices for transferability, it is proposed that that the controller digital and / or analog interfaces for transmission of data. Of course you can over such interfaces not only data of the control unit and the permanent memory, but also in the non-volatile memory are read, in particular for programming the controller.

In A preferred embodiment provides that the control unit in a weatherproof and break-proof, lockable Housing with sun and rain protection is housed. This measure allows the installation of the Control device in publicly accessible Areas, so that the electricity customers day and night access to the control unit to have.

The Control unit according to the invention is suitable not just for the control of small power grids, but also for connection to a main power network for further branching of the main electricity network up to the electricity customers.

With Advantage is the controller programmed so that it after a failure or power failure the consumer lines gradually switched on. This measure allows the start of the generator in the power plant initially without Load and a gradual load up to the maximum allowable Load. The gradual connection of consumer lines recommends But not only after a power failure, but also after a Short circuit on the load side and tripping of circuit breakers, as a result of errors in the performance measurement and data evaluation, after incorrect connection of the measuring and / or switching modules or after a lightning strike.

One Embodiment of the invention will be described below explained in detail the drawing. The figures of the Drawing show in detail:

1 : a schematic representation of the control device according to the invention;

2 : A perspective external view of a control device according to the invention in a preferred embodiment.

In 1 is an inventive control device 1 indicated by a dashed line. A small power station 2 serves to generate the electrical energy. Via a feed-in line 3 The electrical energy passes through a main fuse 4 to an energy distributor 5 which distributes the electrical power to multiple consumer lines 6 distributed, each with a consumer 7 are connected. in the presentation of 1 is symbolically only a single consumer 7 shown. The energy distributor 5 is with switching modules 8th provided, with each consumer line 6 their own switching module 8th having. By means of the switching modules 8th can the respective consumer line 6 and thus the consumer 7 be switched off or switched on by the electrical power supply. A control module 9 is via control lines 10 with the switching modules 8th connected. Furthermore, the control module 9 with a sensor module 11 via signal lines 12 connected. The sensor module 11 serves to record parameters of the power grid such as grid voltage and grid currents. For this it is by means of a sensor line 13 both with the entrance 14 as well as with the outputs 15 of the power distributor 5 connected. The control module 9 includes a microprocessor, not shown, and a non-volatile data memory 16 ,

The control module 9 is programmed so that it is below a value of z. B. 98% of the predetermined power frequency, usually 50 Hz, first a consumer 7 by switching off the respective switching module 8th disconnected from the power supply, so the load on the power plant 2 to reduce. If this measure is not sufficient to raise the grid frequency above the specified minimum value again, the control module switches 9 another consumer 7 until the desired effect is achieved.

In the opposite case, namely when the generator of the power plant 2 due to too little load turns too fast and therefore the mains frequency over a predetermined maximum value of z. B. 102% of the rated frequency deviates upward, the control module switches 9 by pressing the corresponding switch module 8th a consumer 7 to, which increases the load on the generator and leads to a reduction in the mains frequency.

To optimize the stabilization program described is the individual switching modules 8th each assigned a priority value and the control module 9 is programmed so that when selecting the next to be switched off or switching module 8th takes into account the priority value. The priority values are in the data memory 16 stored.

If now a network parameter, in particular the network frequency up or down out of the range tolerable deviations out, so does the control module 9 First determine in which direction the deviation takes place. For example, falls below the grid frequency is an overload of the power plant 2 go out and as a countermeasure electrical loads are dropped. The control module 9 In a next step, determines which loads on which consumer line 6 are switched on and what priority the respectively associated switching module 8th having. From the switching modules 8th Now, the one with the lowest priority is selected or, with two equal priorities, a switching module 8th determined by random decision. This is switched off and then queried the course of the network frequency. If the deactivation does not result in a sufficiently positive tendency for the mains frequency, the described Ver drive repeatedly to from the remaining switched switching modules 8th select and turn off the lowest priority.

in the reverse case, namely when the grid frequency is up out of the tolerable range, is among the switched off switching modules that with the highest Priority determined and this switched on.

The control module 9 is further programmed to be the one from the sensor module 11 supplied network parameters in relation to those in the consumer lines 6 flowing currents monitored and when exceeding a preselected current, the respective switching module 8th turns off to ensure overcurrent protection.

Furthermore, the control module 9 programmed to be the one from the sensor module 11 supplied network parameters to the effect evaluates whether fault currents occur that a consumer line 6 can be assigned to then the associated switching module 8th to turn off, thus providing a residual current protection function. The control module 9 is also programmed to be the one from the sensor module 11 supplied network parameters in order to evaluate which apparent or active services in the various consumer lines 6 flow. The apparent or active power is calculated from voltage, current and the phase shift between voltage and current, which is measured via the sensor module 11 is measurable. When a predetermined value for the apparent or active power in a certain consumer line is exceeded 6 switches the control module 9 that of the consumer administration 6 assigned switching module 8th from.

By integrating a cost-effective metering and billing system for electrical energy and power, electricity customers are encouraged to use electrical energy sparingly and to protect the island grid. They also have the option of using a wide range of high-performance electrical loads, albeit only for a short time and at certain times of the day. For this reason, it is provided that the control unit via a consumer line 6 Over time, electrical energy collected and the values for the total energy consumption of the associated electricity consumer in the data memory 16 stores. The stored data makes it possible to check whether the prepaid amount of energy has already been consumed or not. For this purpose, a maximum value corresponding to the prepaid amount of energy for each power customer is also separately in the data memory 16 stored. The control module 9 Determines if a particular consumer line 6 assigned total energy consumption exceeds the associated maximum value. Once this is the case, the control module will switch 9 that of the respective consumer management 6 assigned switching module 8th from. This prevents energy consumption beyond the prepaid amount of energy.

The control unit 1 is with a prepayment module 18 provided, which via a data line 19 with the control module 9 connected is. The prepayment module has a card reader for reading chip cards 20 the electricity customer. After paying for an energy package, the chip card 20 be "charged" at a central point of sale. It is on the chip card 20 a data packet stored by the card reader of the prepayment module 18 read out and via the control module 9 can be further processed. The control module 9 determines from the data packet in particular the prepaid amount of energy and adds it to the data store 16 stored maximum value for the respective power customer. Furthermore, values for the maximum apparent power or active power or other parameters agreed with the respective power customer can be taken from the data packet and stored in the data memory 16 be stored. Such parameters may relate in particular to the consumption period.

The currently measured network parameters or in the data memory 16 stored consumption data of the respective consumer as well as other stored or currently determined parameters can be displayed 21 represented and thus made accessible to a service technician without the technician bring their own reading device and the control unit 1 would have to connect. On the display 21 The balances of individual electricity customers can also be displayed in order to enable them to easily control their remaining balance. The control unit is equipped with a digital interface 22 for connecting an external device 24 and with an analog interface 23 for connecting another external device 25 Mistake. The interfaces are used to read data from the data memory 16 or for reading out parameters that the sensor module 11 determines and provides.

How to best in 2 detects, is the controller 1 in a weatherproof and break-proof lockable housing 26 with sun and rain protection 27 accommodated. The housing 26 is with a castle 28 provided and thereby protected against unauthorized interference.

If, despite the described network management, a collapse of the island grid occurs, the power grid must be rebooted. This only works reliably if a load-free start-up of the power plant is guaranteed and the Switch on loads gradually after the start-up procedure. That's why the controller is 1 programmed so that it after a failure or a power failure, the consumer lines 6 gradually switched on.

Furthermore, a mixed operation of the network on the one hand as a stand-alone grid and on the other hand to branch a main power grid is feasible. As long as the main grid supplies enough energy, it will become the net powerhouse 2 shut off and the controller 1 serves only for further branching of the electrical power from the main power grid. As soon as the power supply through the main power grid is insufficient or completely failing, the net power plant becomes 2 switched on and forms together with the control unit 1 and the consumer lines 6 an independent island network.

1

control unit

2

power plant

3

feeder

4

main fuse

5

energy distributors

6

consumer lines

7

consumer

8th

switching module

9

control module

10

control lines

11

sensor module

12

signal line

13

sensor line

14

entrance

15

outputs

16

data storage

17

data line

18

Prepayment module

19

data line

20

smart card

21

display

22

digital interface

23

analog interface

24

external device

25

external device

26

casing

27

To sunbathe- and rain protection

28

lock

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 00/77527 A2 [0002]

Claims (19)

Small power grid controller for use as an interface between one or more generators ( 2 ) and individual electricity consumers ( 7 ) with an energy distributor ( 5 ) for branching the electrical power from a feed line ( 3 ) of the generator or of the small electricity network ( 2 ) on several consumer lines ( 6 ), characterized in that the energy distributor ( 5 ) Switching modules ( 8th ) for connecting or disconnecting the respective consumer line ( 6 ), wherein the switching modules ( 8th ) from a control module ( 9 ) are switchable, that the control module ( 9 ) with a sensor module ( 11 ) is connected to the detection of voltage and currents of the power network and that the control module ( 9 ) individual predetermined switching modules ( 8th ) in the sense of stabilizing at least one of the sensor module ( 11 ) generated network parameters such as the grid frequency is switched on or off. Control unit according to claim 1, characterized in that the control module ( 9 ) a program-controlled microprocessor and a non-volatile data memory ( 16 ) having. Control unit according to Claim 1 or 2, characterized in that the control module ( 9 ) at a drop in the mains frequency below a predetermined value one or more switching modules ( 8th ) is designed to turn off. Control unit according to one of the preceding claims, characterized in that the control module ( 9 ) at an increase in the mains frequency over a predetermined value one or more switching modules ( 8th ) is designed to be connected. Control device according to one of the preceding claims, characterized in that the switching modules ( 8th ) is assigned in each case a priority value and that the control module ( 9 ) in the selection of the next to be switched on or off switching module ( 8th ) takes into account its priority value. Control device according to one of the preceding claims, characterized in that it comprises an overcurrent protection device and that the control module ( 9 ) a switching module ( 8th ) is switched off when in the associated consumer line ( 6 ) a predetermined current is exceeded. Controller according to one of the preceding claims, characterized in that it comprises a residual current device and that the control module ( 9 ) a switching module ( 8th ) is switched off when, in conjunction with the associated consumer line ( 6 ) Fault currents occur. Control device according to one of the preceding claims, characterized in that it is that of a consumer line ( 6 ) recorded and stored and that when the time-averaged apparent or active power above a predetermined value, the control module ( 9 ) the associated switching module ( 8th ) Abschaltend is configured. Control unit according to one of the preceding claims, characterized in that it via a consumer line ( 6 ) electrical energy flowing over time and the values for the total energy consumption of the associated electricity consumer in the data memory ( 16 ) stores. Control unit according to Claim 9, characterized in that the control module ( 9 ) that of a consumer 6 ) associated switching module ( 8th ) Abschaltend is configured as soon as a predetermined and in the data memory ( 16 ) stored maximum value for the total energy consumption is exceeded. Control unit according to Claim 9 or 10, characterized in that it has a prepayment module ( 18 ), with which prepayments of electricity customers can be detected, and a new maximum value calculated in accordance with a prepayment for a consumer line ( 6 ) associated total energy consumption is stored. Control device according to one of claims 9 to 11, characterized in that via the prepayment module ( 18 ) further of the respective consumer line ( 6 ) of a power customer associated parameters such as maximum removable apparent or active power or consumption period can be selected by the power customer and / or read and stored. Control device according to one of Claims 9 to 12, characterized in that it has a display ( 21 ) for displaying currently measured and / or stored parameters and / or consumption data. Control unit according to claim 13, characterized in that on the display ( 21 ) the balances of individual electricity customers can be displayed. Control device according to one of the claims 9 to 14, characterized in that all network data and / or consumption data can be stored and for determining the quality of the power grid and / or purpose Determination of the usage behavior of the electricity customers available and / or are representable. Control unit according to one of the preceding Claims, characterized in that it is digital ( 22 ) and / or analog interfaces ( 23 ) for transmission of data. Control device according to one of the preceding claims, characterized in that it is in a weatherproof and break-proof, lockable housing ( 26 ) with sun and rain protection ( 27 ) is housed. Control device according to one of the preceding claims, characterized in that it is for branching a main power network is usable. Control device according to one of the preceding claims, characterized in that after a fault or a power failure, the consumer lines ( 6 ) is gradually switched on.