Method to control one or several power generator plants. RU patent 2479908.

FIELD: electricity.

SUBSTANCE: load capacity is measured, capacity of power generators is measured, the difference of specified capacities is defined, the produced value is used to generate a signal of capacity control as a control action to change the capacity of power generator plants, control is carried out in the mode of operation in parallel with the external grid, or in the mode of operation as isolated from the grid, in the mode of operation in parallel with the grid when generating a signal of capacity control, a signal of request for disconnection of one or more loads is used, using which values of capacities of disconnected loads are subtracted from the previously determined difference, in case of equality of the grid capacity and the total capacity of disconnected loads, a control signal is generated for disconnection of requested loads, and if the capacity value from the grid is reduced below the specified value, connection of ballast resistances is carried out with subsequent smooth reduction of ballast capacity. When operating as isolated from the grid, a signal of request for loads connection is used, added capacity is determined as the value of capacities of connected loads, and a signal is generated for smooth connection of ballast resistances with the speed of not more than the specified value, in case of equality of capacities on ballast resistances and added power, ballast resistances are disconnected, and requested loads are connected.

EFFECT: increased efficiency of power generator system control.

3 cl, 2 dwg

The invention relates to the field of automatic control electrical generators on the basis of internal combustion engines and can be used in energy complexes of power supply to consumers.

Known to the system and the way the team manage multiple turbogenerators (US patent US 6,664,653 B1, IPC F02N 11/06, 02 9/04, 02 23/52, 06.12.2003), including several turbogenerators, bidirectional wattmeter, several disconnect switch, chief controller, switchboard, time relay and bus command control. Main the controller is connected via a bus command control to each of the controllers turbogenerators and to and produces start, stop, power regulation of each of the several individual turbine generators with automatic restart in the event of a breakpoint on a fault in the selected mode of operation.

This well-known system and method differs reliability and economic efficiency when working in parallel with the network mode sequence loading, when the share of power is maintained at zero level. The disadvantage of this system and method is the appearance of the power flow into the external supply network when you disable one or several consumers at the moment when generating capacity of interruptible consumers exceeds the value of the power consumed from the network. Time interval power flow in the network can be up to several tens of seconds or minutes. Thus, the known system and method may not be used at the sites, where the technical requirements is not allowed to flow capacity in the network, for example in power systems, where the total power of electric generators external mains comparable or close to a total power generating sets that can lead to instability of the entire system of supply.

Known power generation system, working as the island (isolated from the external mains mode, in parallel with an external charger (US patent # 7,122,916 B2, cl. H02J 3/04 (2006.1), consisting of several parallel generators, system switch between the island mode, and parallel work with the external network, which includes the power meter and the necessary switching elements, control system, manages the power and switching system, communication bus, unifying system control for each generator, communication bus synchronization, uniting between the generators and a set of I/o busses to specify the external command to influence from the local or the remote operator. In this famous system use a signal and the power generating sets and the signal power consumption from the external mains to regulate the number of working power generators and power depending on the current mode. The disadvantage of this well-known system is the emergence of a reverse flow in parallel with the network when installed power of interruptible consumers exceeds the value of the power consumed from the network. How such a system does not address this deficiency.

Also known management system diesel generator, gas-piston and turbo-generator plants operating in isolation from the network in island mode of generating electrical energy [MSLC/DSLC, http://woodward.com; InteliGen and InteliSys-NT, http://comap.cz]. The maximum possible one-time load surge for these systems is no more than 25-30 per cent of the nominal capacity of the plant, that is by design of internal combustion engines. This leads to the necessity of overestimate of the unit installation power generators and consequently unnecessary economic costs.

The closest analogues listed is the way to manage multiple turbo-generators, working, including in the mode sequence loading (US patent # 6,664,653), which is selected as a prototype.

Is implemented in this system the way the command control mode sequence loading is carried out as follows. When operation sequence loading network compare the value of load power with power output of all electricity generation systems, further the received signal mismatch (error) integrate in a given time interval and then used to form the control signal at the change of power generation capacity of generators, and produce a comparison of the power generation capacity of each installation with prescribed boundary values, the power generation capacity of above or below a specified values produce respectively connection or disconnection of one or several generating sets depending on operating time. Mode of work in isolation from the external mains in this way is not presented.

The disadvantage of this famous method is the lack of control actions on emerging shift of power to the external supply network when you disable one or several consumers at the moment when generating capacity of interruptible consumers exceeds the value power consumed from the network, that forces them to maintain power consumption of the network at the level of power the largest consumer in cases where the flow of power network is invalid. This leads to unstable operation of the whole system.

Object of the present invention is to increase the reliability of power supply to consumers by increasing the effectiveness of the management system of generators.

The technical result of the proposed method is expressed in increasing the effectiveness of management system of generators in operation modes, which can occur with unstable power supply system.

This technical result is achieved by the method of management of one or more of the electricity generation systems, which measure the power load, measure the power generated power, to determine the difference in the powers generators and loads the resulting value is used for signal power regulation as managing impact on the change of power generating sets, managed by either mode of operation in parallel with the external supply network, or in a mode of work in isolation from the network, in the mode of operation in parallel with the external supply network signal generation regulation of capacity use a signal request to shut off one or more consumer, which from a certain previously difference capacities generators and loads subtract values of powers interruptible loads, advanced subtract values of powers interruptible loads this at equality of external power supply network and total power of interruptible consumers form a managing signal for switching off of the requested consumers, whereas at decreasing the value of the power of the network is less than the specified values produce the connection ballast resistance followed by smooth decrease of power of ballast, mode of work in isolation from the network during the formation of the control action use a signal request to connect one or several consumers determine the incremental capacity as the value of the capacity of connected consumers and signal smooth connection ballast resistors with a speed no more than the specified value, with equal power on ballast resistors and incremental power cutoff the ballast resistance and connection requested by consumers.

A search for the sources of patent and technical information claimed combination of features was found, that allows to consider this solution, corresponding to the criteria of «novelty». With the introduction of the distinguishing signs of a common set of essential features the method allows to organize the management of the system of generators of the need to avoid the unstable state of the system, arising when operating in different modes, in parallel with an external supply network or in isolation from it, and caused a reverse power flow into the external supply network or overnight load.

Figure 2 presents structural scheme of the system for the implementation of the proposed method of management. Figure 2 shows:

1 - external power supply network;

2 - the network switch;

3 - bus power supply of consumers;

4 - switches consumers;

5 - consumer (load);

6 - group switch generating sets;

7 - switches power generators;

8 - generators;

9 - digital power meter;

10 - bus control signal power from the network;

11 - master-controller;

12 - control bus power generators;

13 - bus control group switch power generators;

14 - bus control the status of the network switch;

15 - bus request connecting/disconnecting of consumers;

16 - management bus connection/disconnection of consumers;

17 - power of ballast resistance;

18 - block ballast resistance;

19 - bus management capacity of ballast resistance.

External power supply network 1 (see figure 2) is connected through a network switch 2 to the bus 3 power consumers, which through individual switch 4 inputs are connected consumers 5, through a switch ballast resistors 17 entrance of the block of ballast resistors 18, as well as through group switch 6 generators and the individual switches 7 outputs are connected to generators 8. The first and second inputs master controller 11 connected respectively to the output of the digital power meter 9 and to the signal contact the status of the network switch 2. The third entrance of the master controller 11 via bus query 15 is connected to the outputs of the request enable/disable consumers 5, power inputs are connected via the switches 4 users with bus 3 power supply of consumers. The first output of the master controller 11 is connected to the inputs of the control electric generators 8 the control bus power 12 outputs are via the switches 7 are connected with the group switch 6 connected to the bus-3 supply to consumers and to the external mains. The second output of the master controller 11 is connected to the input control unit ballast resistors 18 via bus 19 management capacity of ballast resistance. The third master output controller 11 is connected to the control circuits breakers 4 consumers and switch block 17 18 ballast resistance through the control bus 16, and the fourth exit the wizard controller 11 is connected to the control circuitry group switch 6 via bus control 13.

All the system devices are known in the prior art. Master-controller 11 can be executed on the basis of industrial controller, for example, a series IA-261 company MOHA. The controller is installed in the electrical Cabinet width 600 mm, height of 600 mm and a depth of 300 mm in Cabinet is furnished with I/o modules, such as the I-7000 company ICP DAS, accessories - uninterruptible power supply with power batteries, terminals for external connections (bus 10, 12, 13, 15, 16 and 19 according to figure 2), switches to specify operating modes of the master controller, lamp, or touch the display to show the current status of the master controller. Digital power meter can be installed in the immediate vicinity of the power switch. To maintain the required temperature inside the Cabinet can be installed automatic system of heating the air, such as a series of HVL 031 company STEGO.

The system implements the proposed method of control of one or several electricity generation systems, in accordance with the flowchart of the algorithm in figure 1, is as follows.

To determine the difference loads and generators used power meter, 9 from which the signal mismatch power loads and power generators (according to the first law of Kirchhoff) comes bus power control 10 in the master controller 11. The master controller is connected to the generator 8 through the control bus power generators 12, which produces regulation of the power generators. The master controller is connected to the management bus 13, which outputs a trip of group of the switch power generators with prolonged flow of power to the external supply network 1.

Signal the status of your network switch 2 is output through the control of the state power switch 14 in the master controller 11, which determine the mode of operation: stand-alone or in parallel with the network. From the digital power meter 9 in the master controller receives a signal on the power flowing through the network switch 2. The signal request for activation or deactivation enters the master controller via the bus 15. Master-controller 11 calculates the average value of power flowing through the power switch on the given interval, which, for example, may be in the range from 20 MS to 3 seconds, in the same way, it is determined the medium power generated by electric generators. Master-controller 11 produces regulation of the power generated electricity generation systems 8, the control bus 12 so that the power flowing through the network switch was equal to zero.

When requested by bus 15 for the connection of one or several consumers 5 in parallel with the network (if the network switch 2) master controller makes the inclusion of relevant switches 4 requested consumers 5. When you receive a query bus 15 on the inclusion of one or several consumers 5 in island mode (when the mains switch 2) the master controller 11 defines the capacity of connected consumers by summing their capacity multiplied on factor of a starting current of each requested the consumer: RP=P1 x K1+P2 x K2+RP X-KP and then produces a continuous increase of power of the Republic of Belarus ballast resistor 18 from zero to the calculated value of RP during the time t. The time s is measured by the ratio of TL/Vp where Vp - total speed of restructuring of the capacity of all working generating sets. When reaching the capacity of ballast PN, master controller performs simultaneous connection of switches 4 required consumers to 5 and off the ballast resistor 18. Change of power of ballast load produce a well-known method for thyristor regulation. In those energy systems, where unacceptable appearance of the higher harmonics of voltage and currents regulation, proposed to use the method of combined dialup connection resistance of different (unequal) power, each of which is commuted high-speed electronic control unit. Power ballast with minimal resistance is chosen based on the desired accuracy of the regulation with total capacity of ballast. Capacity of each subsequent resistance is selected in increments of two from the previous one. For example, propose the following range of resistors: 1 kW, 2 kW, 4 kW 8 kW, 16 kW, 32 kW, 64 kW, 128 kW. In this case, a minimum power is 1 kW, maximum 255 kW, and the regulation step 1 kW. Switching ballast resistors produce at the moment of transition curve at zero voltage.

When a request to shut off one or more consumer 5 in island mode master controller does disconnecting switches 4 requested consumers 5. When you receive a signal on the disabling one or several consumers 5 in the mode of parallel network master controller calculates the power of interruptible consumers summation of their capacity: RP=P1+P2+RP and then reduction of the power generated power until the power, flowing through the network switch equals RP (the first law Kirchhoff), after which the master controller produces circuit breakers 4 requested consumers 5.

While reducing power RS flowing through the network switch below zero, and the emergence of a reverse flow the external supply network), which can occur when an unscheduled sudden disconnection of one or more consumers, the master controller connects ballast resistance block 18 power equal RB=|PC|X, where RS - the value of the power flow in the network, the K - factor of safety, that can be, for example, in the range from 1.0 to 5.0. After connecting ballast 18, the master controller 11 produces a gradual decrease in power ballast resistor 18 to zero over a period of time t. The time s is measured by the ratio RB/Vp where Vp - total speed of restructuring of the capacity of all working generating sets. During the time t electric generating sets 8 rebuild (reduce) the generated power on commands coming from the master controller 11.

At long reduce the power of the PC running through the network switch below zero over a given time t, the master controller does disabling the group generator switch 6 on management bus 13.