UFR device, power system stabilization method and program

Abstract

To provide an UFR device capable of easily and fairly controlling a circuit breaker.SOLUTION: A UFR device includes: a plurality of abnormality detection units; a selection unit; a control output unit; and a control conditions switching unit. The abnormality detection unit detects abnormality in a frequency of a voltage of a power system. The selection unit selects a load based on control conditions indicating a correspondence relation between the abnormality detection unit that detects abnormality and the load connected to the power system. The control output unit controls a circuit breaker corresponding to the load selected by a control target selection unit to interrupt the power system and the selected load. The control conditions switching unit switches the control conditions.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a UFR device, a power system stabilization method, and a program.

Background Art

[0002] In a power system, as a countermeasure when the frequency of power decreases, an under-frequency relay (UFR) may be installed in the system to control the loads connected to the power system when the frequency of power decreases. At this time, fairness is required for the priority of the loads to be controlled. Therefore, the priority may be changed by manually changing the setting value of each UFR individually.

[0003] However, when manually changing the setting value of each UFR individually for the purpose of changing the priority of the loads, the workload increases as the number of UFR devices in the system increases, and the work may become troublesome.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem to be solved by the present invention is to provide a UFR device, a power system stabilization method, and a program that can simply and fairly control loads.

Means for Solving the Problems

[0006] The UFR device of the embodiment includes a plurality of under-frequency relays (hereinafter referred to as UFRs), a control target selection unit, and a control output unit. The UFR detects an abnormality in the frequency of the voltage. The control target selection unit selects the load based on control conditions indicating the correspondence between the UFR that detects the abnormality and the load that is the control target. The control output unit controls the circuit breaker corresponding to the load selected by the control target selection unit. The control conditions can be switched.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

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Figure 5

Figure 6

Modes for Carrying Out the Invention

[0008] Hereinafter, the UFR device, the power system stabilization method, and the program of the embodiment will be described with reference to the drawings. (First Embodiment) FIG. 1 is a diagram showing the configuration of a power system stabilization system 1 according to the first embodiment. The power system stabilization system 1 includes, for example, a UFR device (frequency reduction relay device) 10, a plurality of k-th circuit breakers 16-k, and a plurality of k-th loads 17-k (k = 1, 2,..., n, the same hereinafter). When distinguishing which circuit breaker or load it is, the "k-th" and the symbols below the hyphen are omitted, and it is described as the circuit breaker 16 and the load 17. In this example, the circuit breaker 16 corresponds to each of the plurality of loads 17, and one circuit breaker 16 is configured to cut off one load 17. Alternatively, one circuit breaker 16 may be configured to cut off a plurality of loads 17. In this case, the circuit breaker 16 may cut off the plurality of loads 17 simultaneously or may cut off the plurality of loads 17 individually. The load 17 is an example of a cut-off target.

[0009] The power system E is a set of a series of facilities for generating electric power and transmitting the generated electric power to the load 17 of the consumer. The power system E is configured, for example, by connecting a plurality of power system units to each other. The power system unit is configured, for example, to be divided by region. The power system E includes, for example, power facilities such as generators, buses, transformers or transmission lines, loads, phase modulation facilities, circuit breakers, and disconnectors. The power system E includes a voltage measurement transformer and a current measurement transformer for measuring the electric power supplied to the power facilities.

[0010] The generators in the power system E include, for example, synchronous generators and asynchronous generators other than synchronous generators. A synchronous generator is a generator in which a rotating body such as a turbine exists and its rotation is synchronized with the frequency of the power system E, and includes, for example, a thermal power generator and a nuclear power generator. Asynchronous generators include, for example, renewable energy generators such as solar power generators and wind power generators.

[0011] The UFR device 10 is provided, for example, in the control terminal devices in a plurality of substations. The UFR device 10 independently detects the degree of abnormal frequency drop in the power system E and sequentially controls the load 17 according to the detected degree of abnormal frequency drop.

[0012] The UFR device 10 includes a voltage acquisition unit 11, an abnormality detection unit 12, a timer 13, a control target selection unit 14, and a control output unit 15. In the UFR device 10, a setting value is set in the abnormality detection unit 12, a set time is set in the timer 13, and a control condition is set in the control target selection unit 14. The setting value, the set value, and the control condition are set in the UFR device 10 as reference information. The setting value is a reference for detecting a frequency abnormality occurring in the power system E, and is a setting value for the frequency of the system voltage in the power system E. The set time is a reference for determining to control the circuit breaker 16 and cut off the load 17 with respect to the time during which the frequency abnormality occurring in the power system E continues. The control condition is provided in the abnormality detection unit 12 and indicates the correspondence relationship between the k-th UFR 12-k that has detected an abnormality and the load 17 that is the control target.

[0013] The voltage acquisition unit 11 acquires the system voltage in the power system E. The voltage acquisition unit 11 outputs the acquired system voltage to the abnormality detection unit 12. The abnormality detection unit 12 includes, for example, the k-th UFR (frequency decrease relay) 12-k. The k-th setting value UFk is set for each UFR in the k-th UFR 12-k in association therewith. The abnormality detection unit 12 detects a frequency abnormality by comparing the frequency of the system voltage output by the voltage acquisition unit 11 with the setting value of the k-th UFR 12-k. When the k-th UFR 12-k detects a frequency abnormality, the k-th UFR 12-k outputs an abnormality signal to the timer 13.

[0014] The timer 13 includes, for example, the k-th timer 13-k. The first timer 13-1 stores, for example, the k-th set time Tk. When an abnormality signal is output by the k-th UFR 12-k, the k-th timer 13-k measures the abnormality occurrence time at which the abnormality signal was output. The k-th timer 13-k determines whether or not the measured time (hereinafter, "measurement time") has elapsed the set set time.

[0015] When the measurement time of the k-th timer 13-k has elapsed the respective k-th set time Tk, the k-th UFR 12-k outputs detection information indicating that a frequency abnormality has been detected to the control target selection unit 14. For example, when the measurement time of the first timer 13-1 has elapsed the first set time T1, the first detection information indicating that the first UFR 12-1 has detected a frequency abnormality, and when the measurement time has elapsed the n-th set time Tn, the n-th detection information indicating that the n-th UFR 12-n has detected a frequency abnormality are output to the control target selection unit 14.

[0016] The control target selection unit 14 selects the load 17 based on the detection information and a control condition indicating the correspondence between the k-th UFR 12-k that detects an abnormality and the load 17. The control target selection unit 14 has a plurality of control conditions. FIG. 2 shows an example of the control condition. For example, in the first control condition, the first UFR 12-1 corresponds to the n-th load 17-n, the second UFR 12-2 corresponds to the first load 17-1, and the n-th UFR 12-n corresponds to the second load 17-2. For example, in the second control condition, the first UFR 12-1 corresponds to the first load 17-1, the second UFR 12-2 corresponds to the second load 17-2, and the n-th UFR 12-n corresponds to the n-th load 17-n. In the control condition, the k-th UFR 12-k may be the k-th setting value UFk. In the control condition, the load 17 may be the circuit breaker 16.

[0017] In the control condition, the correspondence between the UFR 12 and the load 17 does not have to be a one-to-one correspondence. For example, a plurality of different loads 17 may correspond to one UFR 12, or a plurality of different UFR 12s may correspond to one load 17.

[0018] When the load 17 is selected by the control target selection unit 14, the control output unit 15 outputs a cutoff command corresponding to the selected load to the circuit breaker 16. For example, when the first load 17-1 is selected by the control target selection unit 14, the control output unit 15 outputs a cutoff command to the first circuit breaker 16-1. Also, for example, when the n-th load 17-n is selected by the control target selection unit 14, the control output unit 15 outputs a cutoff command to the n-th circuit breaker 16-n.

[0019] The breaker 16 interrupts the corresponding load 17 from the power grid E based on the interruption command output by the control output unit 15 of the UFR device 10. For example, the first breaker 16-1 interrupts the first load 17-1 from the power grid E.

[0020] The control target selection unit 14 and the control output unit 15 are realized, for example, by a hardware processor such as a CPU (Central Processing Unit) (computer) executing a program (software). Also, some or all of these components may be realized by hardware (including a circuit unit; circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by the cooperation of software and hardware. The program may be stored in advance in a storage device (a storage device having a non-transitory storage medium) such as the HDD or flash memory of the controller, or may be stored in a removable storage medium such as a DVD or CD-ROM, and may be installed in the storage device by mounting the storage medium (non-transitory storage medium) on a drive device.

[0021] The following specific examples are given to explain that different control conditions result in different loads 17 being disconnected from the power system E. When the control condition used by the control target selection unit 14 (hereinafter referred to as the in-use control condition) is the first control condition, when the first UFR 12-1 detects an abnormality, the control target selection unit 14 selects the nth load 17-n as the load to be controlled, and the control output unit 15 outputs a disconnection command to the nth circuit breaker 16-n corresponding to the nth load 17-n, and the nth circuit breaker 16-n disconnects the power supplied to the nth load 17-n. On the other hand, when the in-use control condition is the second control condition, when the first UFR 12-1 detects an abnormality, the control target selection unit 14 selects the first load 17-1 as the load to be controlled, and the control output unit 15 outputs a disconnection command to the first circuit breaker 16-1 corresponding to the first load 17-1, and the first circuit breaker 16-1 disconnects the power supplied to the first load 17-1.

[0022] The control target selection unit 14 switches the control condition that is the in-use control condition. Therefore, even if the UFR 12 that detects an abnormality is the same, the load 17 may be different. Hereinafter, the configuration of the control target selection unit 14 according to each embodiment will be described, and it will be described based on what the control target selection unit 14 according to each embodiment switches the control condition that is the in-use control condition. FIG. 3 is a diagram showing the configuration of the control target selection unit 14 according to the first embodiment. The control target selection unit 14 according to the first embodiment includes a selection unit 141, a control condition switching unit 142, and a control condition storage unit 143.

[0023] The selection unit 141 selects the load 17 based on the detection information and the in-use control condition.

[0024] The control condition switching unit 142 switches the in-use control condition to one of the control conditions stored in the control condition storage unit 143 when a control condition switching signal is input. The control condition switching signal is a signal input from an external device such as a remote control device 22 installed outside. The remote control device 22 may be configured to be controlled by the control station 21 and transmit a control condition switching signal. The control station 21 may be configured to control a plurality of remote control devices 22, and each remote control device 22 transmits a control condition switching signal to a different UFR device 10.

[0025] The control condition storage unit 143 stores a plurality of control conditions. The plurality of control conditions stored in the control condition storage unit 143 have an order, and the control condition switching unit 142 may switch the control condition that is the currently used control condition according to the order. The control condition switching unit 142 may randomly select the control condition that is the currently used control condition from the plurality of control conditions stored in the control condition storage unit 143.

[0026] With the above configuration, when the control target selection unit 14 according to the first embodiment receives a control condition switching signal, it switches the control condition that is the currently used control condition. Thereby, the control conditions can be made different, and even if the kUFR12 - k for detecting an abnormality is the same, the loads 17 whose power supply is cut off can be made different. Therefore, the opportunities for controlling the load 17 can be averaged.

[0027] (Second Embodiment) FIG. 4 is a diagram showing the configuration of the control target selection unit 14 according to the second embodiment. The control target selection unit 14 according to the second embodiment includes a time determination unit 144 in addition to the control target selection unit 14 according to the first embodiment.

[0028] The time determination unit 144 acquires time information from the time information output device 31. The time information output device 31 outputs time information. The time information output device 31 is, for example, a real - time clock. The time information output device 31 is provided in the UFR device 10, for example. The time determination unit 144 determines whether the time indicated by the acquired time information is a predetermined time. For example, the time determination unit 144 determines whether the time indicated by the acquired time information is 0:00 am. The time determination unit 144 may determine that the time indicated by the time information acquired at a certain point in time is before the predetermined time and the time indicated by the time information acquired at the next point in time is after the predetermined time, and then determine that the time indicated by the time information acquired at the next point in time is the predetermined time.

[0029] When the time determination unit 144 determines that the time indicated by the time information is a predetermined time, the control condition switching unit 142 according to the second embodiment switches the in-use control condition to one of the control conditions stored in the control condition storage unit 143.

[0030] With the above configuration, the control target selection unit 14 according to the second embodiment switches the control condition that is the in-use control condition based on the time information acquired from the time information output device 31 provided in the UFR device 10. Thereby, the in-use control condition can be switched without communicating with an external device, and the opportunity for the load 17 to be controlled can be averaged.

[0031] (Third Embodiment) FIG. 5 is a diagram showing the configuration of the power system stabilization system 1 according to the third embodiment. The UFR device 10 according to the third embodiment includes a system abnormality detection unit 41, which is different from the UFR device 10 according to the first embodiment.

[0032] The system abnormality detection unit 41 detects an abnormality in the frequency of the voltage taken in from the voltage intake unit 11, similar to the abnormality detection unit 12. When the system abnormality detection unit 41 detects an abnormality in the frequency, it outputs a control condition switching signal to the control condition switching unit 142. The setting value set for the system abnormality detection unit 41 may be a value higher than any of the k-th setting values UFk of the kUFR12-k included in the abnormality detection unit 12. That is, when the frequency of the voltage taken in from the voltage intake unit 11 starts to decrease, the system abnormality detection unit 41 operates before the abnormality detection unit 12, and the control condition switching unit 142 switches the control condition that is the in-use control condition.

[0033] The system abnormality detection unit 41 may output a control condition switching signal to the control condition switching unit 142 when the abnormality in the frequency is no longer detected after detecting the abnormality in the frequency.

[0034] When a control condition switching signal is input from the system abnormality detection unit 41, the control condition switching unit 142 of the control target selection unit 14 switches the in-use control condition to one of the control conditions stored in the control condition storage unit 143.

[0035] With the above configuration, when the system abnormality detection unit 41 provided in the UFR device 10 detects an abnormality, the control target selection unit 14 according to the third embodiment switches the control condition that is the control condition during use. As a result, the control condition during use can be switched without communicating with an external device, and the opportunity to control the load 17 can be averaged.

[0036] When the system abnormality detection unit 41 outputs a control condition switching signal to the control condition switching unit 142 when the frequency abnormality is no longer detected after detecting the frequency abnormality, since the control condition during use is switched after the abnormality detection unit 12 detects an abnormality, it is possible to prepare for the next frequency abnormality detection.

[0037] (Fourth Embodiment) FIG. 6 is a diagram showing the configuration of the control target selection unit 14 according to the fourth embodiment. The control target selection unit 14 according to the fourth embodiment includes a control condition number determination unit 145 in addition to the control target selection unit 14 according to the first embodiment.

[0038] The control condition number determination unit 145 acquires time information from the time information output device 31. The time information output device 31 is, for example, a real-time clock. The time information output device 31 is provided in the UFR device 10, for example. The control condition number determination unit 145 determines the number of the control condition based on the date indicated by the acquired time information. For example, the i (i is an integer of 2 or more) control conditions stored in the control condition storage unit 143 are each assigned a number from 1 to i, and the control condition number determination unit 145 adds 1 to the remainder when the number of days from the fixed date to the date indicated by the acquired time information is divided by n to determine the number of the control condition. When the control condition storage unit 143 stores 7 control conditions and the date indicated by the time information acquired from the fixed date is 50 days, since the number obtained by adding 1 to the remainder when 50 is divided by 7 is 2, the control condition number determination unit 145 determines that the number of the control condition is 2.

[0039] The control condition switching unit 142 switches the control condition in use to the control condition assigned the number determined by the control condition number determination unit 145.

[0040] With the above configuration, the control target selection unit 14 according to the fourth embodiment switches the control condition that is the control condition in use based on the time information acquired from the time information output device 31 provided in the UFR device 10. Thereby, the opportunity to control the load 17 can be averaged without communicating with an external device.

[0041] The configurations of the UFR device 10 according to the first to fourth embodiments can be combined. For example, the UFR device 10 according to the second embodiment and the UFR device 10 according to the third embodiment are combined, and the control condition switching unit 142 determines that the time indicated by the time information by the time determination unit 144 is a predetermined time and a control condition switching signal is input from the system abnormality detection unit 41. In both cases, the control condition that is the control condition in use may be switched.

[0042] According to at least one of the embodiments described above, the control target selection unit 14 can average the opportunity to control the load 17 by switching the control condition that is the control condition in use.

[0043] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0044] 1... Power system stabilization system, 10... UFR device, 11... Voltage acquisition unit, 12... Abnormality detection unit, 13... Timer, 14... Control target selection unit, 141... Selection unit, 142... Control condition switching unit, 143... Control condition storage unit, 144... Time determination unit, 145... Control condition number determination unit, 15... Control output unit, 16... Circuit breaker, 17... Load, 21... Control station, 22... Remote control device, 31... Time information output device, 41... System abnormality detection unit, E... Power system

Claims

1. A plurality of abnormality detection units that detect an abnormality in the frequency of the voltage of the power system; a selection unit that selects the load based on a control condition indicating a correspondence relationship between the abnormality detection unit that detects an abnormality and the load connected to the power grid; a control output unit that controls a breaker corresponding to the load selected by the selection unit to break the connection between the power system and the selected load; A control condition switching unit that switches the control condition; a system abnormality detection unit that detects an abnormality in the frequency of the voltage at a setting value higher than that of the abnormality detection unit; Equipped with the control condition switching unit switches the control condition when the system abnormality detection unit detects an abnormality in the frequency of the voltage. UFR device.

2. A time information output device for outputting time information is provided, The control condition switching unit switches the control condition based on the time information. The UFR device of claim 1 .

3. A time information output device for outputting time information is provided, the control condition switching unit calculates a number based on the time information, and switches the control condition to a control condition corresponding to the calculated number.

3. The UFR device according to claim 1 or 2.

4. Detects abnormalities in the voltage frequency of the power grid, selecting the load based on a control condition indicating a correspondence relationship between the setting value in the abnormality detection and the load connected to the power grid; Controlling a circuit breaker corresponding to a selected load to disconnect the power grid from the selected load; Detecting an abnormality in the frequency of the voltage at a setting value higher than the setting value used in the abnormality detection; switching the control condition when an abnormality in the frequency of the voltage is detected at the high setpoint; Power system stabilization method.

5. On the computer, when an abnormality is detected in the frequency of a voltage of the power system, selecting the load based on a control condition indicating a correspondence relationship between a setting value at the time of the abnormality detection and a load connected to the power system; Controlling a circuit breaker corresponding to a selected load to disconnect the power grid from the selected load; When an abnormality in the frequency of the voltage is detected at a setting value higher than the setting value used in the abnormality detection, the control condition is switched. program.

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