JP6914713B2 - Power system monitoring device and power system monitoring method - Google Patents

Description

Embodiments of the present invention relate to a power system monitoring device and a power system monitoring method.

Conventionally, a power system monitoring device that measures the instantaneous values of the voltage of each generator in a wide area system and the voltage of the reference bus, and calculates the voltage phase difference from each instantaneous value data to determine whether or not the power system is out of step. It has been known. In the above technology, synchronous control is required between the equipment on the measurement side and the equipment on the calculation side, which may complicate the configuration and the cost for realizing the configuration may be high. rice field. A method of estimating the voltage phase difference between one generator and the main system from the line impedance to perform step-out determination is known, but in this method, a wide area system for observing a plurality of generators is known. Is difficult to monitor.

Japanese Unexamined Patent Publication No. 8-33208

An object to be solved by the present invention is to provide a power system monitoring device and a power system monitoring method capable of determining a step-out tendency of a generator without requiring synchronous control.

The power system monitoring device of the embodiment includes a measuring unit, a storage unit, a phase angle change amount calculation unit, and a determination unit. The measuring unit measures the voltage phase of the generator to be monitored. The storage unit stores the measurement result of the voltage phase measured by the measuring unit. The phase angle change amount calculation unit calculates the phase angle change amount in the first predetermined time based on the measurement result of the voltage phase stored in the storage unit. The determination unit determines whether or not the generator tends to step out based on the phase angle change amount calculated by the phase angle change amount calculation unit. The phase angle change amount calculation unit acquires the phase angle change amount in the first predetermined time by repeatedly calculating and accumulating the phase angle change amount in the second predetermined time shorter than the first predetermined time.

FIG. 3 is a configuration diagram of a monitoring system 1 including the power system monitoring device 100 of the first embodiment. The figure for demonstrating the calculation content of the phase angle change amount calculation unit 141. The flowchart for demonstrating the step-out tendency determination processing of 1st Embodiment. FIG. 3 is a configuration diagram of a monitoring system 2 including the power system monitoring device 100A of the second embodiment. FIG. 3 is a configuration diagram of a monitoring system 3 including the power system monitoring device 100B of the third embodiment. The figure for _{demonstrating} the phase angle change amount Δδ g1 and Δδ _{k1 of the 3rd Embodiment.} FIG. 3 is a configuration diagram of a monitoring system 4 including the power system monitoring device 100C of the fourth embodiment. The figure for _{demonstrating} the phase angle change amount Δδ _k2 , Δδ g2 of the 4th embodiment. FIG. 3 is a configuration diagram of a monitoring system 4 including the power system monitoring device 100D of the fifth embodiment. The figure for demonstrating the phase angle change amounts Δδ _k , Δδ _{g of the 5th embodiment.}

Hereinafter, the power system monitoring device and the power system monitoring method of the embodiment will be described with reference to the drawings.

(First Embodiment)
FIG. 1 is a configuration diagram of a monitoring system 1 including the power system monitoring device 100 of the first embodiment. The monitoring system 1 shown in FIG. 1 includes, for example, a generator 10 to be monitored, a transformer 20, and a power system monitoring device 100.

The monitored generator 10 supplies, for example, AC power to the power system. The transformer 20 transforms a voltage and a current with respect to the AC power supplied by the monitored generator 10 by an electromagnetic induction action, and outputs the AC power for monitoring to the power system monitoring device 100.

The power system monitoring device 100 includes, for example, an analog input unit 110, a phase angle detection unit 120, a storage unit 130, an arithmetic processing unit 140, and a control information output unit 150. At least a part of these functional units is a software functional unit that functions by executing a program stored in the storage unit 130 by a processor such as a CPU (Central Processing Unit). Part or all of these functional units may be realized by hardware such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), and FPGA (Field-Programmable Gate Array). Further, a combination of the analog input unit 110 and the phase angle detection unit 120 is an example of the “measurement unit”. Further, the step-out tendency determination unit 142 is an example of the “determination unit”.

The analog input unit 110 includes, for example, an input unit 111 and an A / D conversion unit 112. An analog signal of the voltage of the power system to which the monitored generator 10 is connected is input to the input unit 111. The A / D conversion unit 112 converts an analog signal of the voltage input to the input unit 111 into digital data. The converted digital data is output to the phase angle detection unit 120.

The phase angle detection unit 120 detects the voltage phase of the monitored generator 10 based on the digital data of the voltage input from the analog input unit 110. Further, the phase angle detection unit 120 stores the time-series information of the detected voltage phase in the storage unit 130 as the phase angle information 131.

The storage unit 130 includes, for example, a non-volatile storage medium such as a ROM (Read Only Memory), a flash memory, an HDD (Hard Disk Drive), and an SD card, and a volatile storage medium such as a RAM (Random Access Memory) and a register. It is realized by. The storage unit 130 stores various information such as the phase angle information 131 and the phase angle change amount information 132, for example. The phase angle information 131 is a detection result of the voltage phase of the monitored generator 10 detected by the phase angle detection unit 120. The phase angle change amount information 132 is, for example, a calculation result of the phase angle change amount in the first predetermined time calculated by the phase angle change amount calculation unit 141.

The calculation processing unit 140 includes, for example, a phase angle change amount calculation unit 141 and a step-out tendency determination unit 142. The phase angle change amount calculation unit 141 calculates the phase angle change amount for each second predetermined time based on the phase angle information 131 stored in the storage unit 130. The second predetermined time is, for example, a time shorter than the first predetermined time.

FIG. 2 is a diagram for explaining the calculation content of the phase angle change amount calculation unit 141. The horizontal axis of FIG. 2 indicates the time T, and the vertical axis indicates the phase angle θ. The phase angle change amount calculation unit 141 has a phase angle from the deviation amount of the phase waveform w1 detected by the phase angle detection unit 120 with respect to the preset ideal phase waveform (hereinafter referred to as “reference waveform”) w0. Calculate the amount of change. The reference waveform is, for example, a phase waveform of a voltage obtained from a virtually defined power system that does not have a tendency to step out.

In the example of FIG. 2, the phase angle change amount calculation unit 141 has the difference Δθ1 between the phase angle of the reference waveform w0 and the phase angle of the phase waveform w1 at a certain time T0, and after the second predetermined time has elapsed from the time Tp0. The difference Δθ2 between the phase angle of the reference waveform w0 and the phase angle of the phase waveform w1 at the time Tp1 of Next, the phase angle change amount calculation unit 141 calculates the phase angle change amount Δθ by the difference between Δθ1 and Δθ2. The calculated phase angle change amount is stored in the storage unit 130 as the phase angle change amount information 132. The phase angle change amount calculation unit 141 repeatedly executes the above-mentioned calculation of the phase angle change amount at a predetermined cycle. Further, the phase angle change amount calculation unit 141 acquires the phase angle change amount in the first predetermined time by repeatedly calculating and accumulating the phase angle change amount in the second predetermined time shorter than the first predetermined time.

The step-out tendency determination unit 142 uses, for example, the calculation result of the phase angle change amount in the first predetermined time stored in the storage unit 130 to determine whether or not the cumulative phase angle change amount within the predetermined time exceeds the threshold value. To judge. Then, the step-out tendency determination unit 142 determines that the monitored generator 10 has a step-out tendency when the cumulative amount of phase angle changes within a predetermined time exceeds the threshold value.

The control information output unit 150 transmits control information to the monitored generator 10 when the step-out tendency determination unit 142 determines that the monitored generator 10 has a step-out tendency. The control information is, for example, a command for shutting off the monitored generator 10 from the power system. Further, the control information output unit 150 may output the information regarding the determination result by the step-out tendency determination unit 142 to the administrator terminal of the power system monitoring device 100 or the monitoring system 1, or may store the information in the storage unit 130. good.

FIG. 3 is a flowchart for explaining the step-out tendency determination process of the first embodiment. The flowchart of FIG. 3 is repeatedly executed at a predetermined cycle or a predetermined timing. First, the phase angle detection unit 120 measures the voltage phase of the monitored generator 10 (step S100). The measured voltage phase is stored in the storage unit 130 (step S102). Next, the amount of phase angle change in the first predetermined time is calculated from the voltage phase stored in the storage unit 130 (step S104).

Next, the step-out tendency determination unit 142 determines whether or not the monitored generator 10 has a step-out tendency based on the amount of phase angle change in the first predetermined time (step S106). When it is determined that the monitored generator 10 tends to be out of step, the control information output unit 150 outputs a control command to the monitored generator 10 (step S108), and ends the process of this flowchart. Further, in step S106, if the monitored generator 10 does not tend to step out, the process of this flowchart ends.

As described above, according to the power system monitoring device 100 of the first embodiment, since synchronous control between the measurement side and the calculation side is not required, the step-out tendency of the monitored generator is determined. It can be used for control judgment by post-calculation of the monitoring system. Further, since the power system monitoring device 100 does not need to use system constants such as line impedance, it can be applied to a wide area system for observing a plurality of generators.

(Second Embodiment)
Next, a second embodiment of the power system monitoring device will be described. In the following, the same names and reference numerals will be used for configurations having the same functions as the monitoring system 2 of the first embodiment, and specific description thereof will be omitted.

FIG. 4 is a configuration diagram of a monitoring system 2 including the power system monitoring device 100A of the second embodiment. Compared with the power system monitoring device 100 of the first embodiment, the power system monitoring device 100A includes an accident detection unit 160 and a phase angle change amount calculation unit 141A instead of the phase angle change amount calculation unit 141. Is different. Therefore, in the following, the configuration of the accident detection unit 160 and the phase angle change amount calculation unit 141A will be mainly described.

The accident detection unit 160 detects the occurrence of a system accident by using the voltage information acquired by the analog input unit 110. For example, in the AC voltage analog signal input to the input unit 111, the accident detection unit 160 causes a system accident such as a ground fault in the monitored generator 10 when the amount of change in the amplitude of the voltage is equal to or less than the threshold value. Detect that it is occurring. For example, when the amount of change in the voltage amplitude temporarily falls below the threshold value and then exceeds the threshold value, the accident detection unit 160 sets the time point when the amount of change exceeds the threshold value from the state below the threshold value. It may be detected as the time when an accident occurs.

The phase angle change amount calculation unit 141A uses the time-series phase angle change amount stored in the phase angle change amount information 132 of the storage unit 130 as the first predetermined time with reference to the detection time point of the system accident by the accident detection unit 160. Calculates the cumulative amount of phase angle change until the elapse of. The step-out tendency determination unit 142 determines whether or not the calculated cumulative total exceeds the threshold value, and if the cumulative total exceeds the threshold value, determines that the monitored generator 10 has a step-out tendency.

As described above, the power system monitoring device 100A of the second embodiment has the same effect as that of the first embodiment, and is defeated by the cumulative amount of phase angle change triggered by the occurrence of a system accident. It is possible to make a key judgment. Further, according to the second embodiment, it is possible to determine only the step-out due to a system accident. Further, according to the second embodiment, even when the monitored generator 10 is out of step due to a gradual phase change, if it exceeds the threshold value, it is determined that there is a tendency to out of step and a control command or the like is output. Can be done.

(Third Embodiment)
Next, a third embodiment of the power system monitoring device will be described. In the following, the same names and reference numerals will be used for configurations having the same functions as the monitoring system 2 of the first embodiment, and specific description thereof will be omitted.

FIG. 5 is a configuration diagram of a monitoring system 3 including the power system monitoring device 100B of the third embodiment. The monitoring system 3 of FIG. 5 includes, for example, a generator 10 to be monitored, a transformer 20, a power system monitoring device 100B, and measuring devices 200-1 and 200-2. Compared with the monitoring system 1 in the first embodiment, the monitoring system 3 includes measuring devices 200-1 and 200-2, and the analog input unit 110 provided in the power system monitoring device 100 is the measuring device 200. It differs in that it is provided in each of -1 and 200-2. Therefore, in the following, the measurement devices 200-1 and 200-2 will be mainly described.

The measuring device 200-1 measures the voltage from the power system to which the monitored generator 10 is connected. The measuring device 200-1 includes, for example, an analog input unit 110-1 and a communication unit 113-1. The analog input unit 110-1 includes, for example, an input unit 111-1 and an A / D conversion unit 112-1. The input unit 111-1 inputs an analog signal of the voltage of the power system to which the monitored generator 10 is connected. The A / D conversion unit 112-1 converts the analog signal of the voltage input to the input unit 111-1 into digital data. The communication unit 113-1 transmits the digital data converted by the A / D conversion unit 112-1 to the power system monitoring device 100B via a communication network such as the Internet or a LAN (Local Area Network). The communication unit 113-1 is, for example, a communication interface such as a NIC (Network Interface Card) or a wireless communication module.

The measuring device 200-2 measures, for example, the bus voltage of the reference electric station. The reference electric station is, for example, a power plant or a substation that supplies stable electric power that does not depend on a voltage change of one generator. The measuring device 200-2 includes, for example, an analog input unit 110-2 and a communication unit 113-2. The analog input unit 110-2 includes, for example, an input unit 111-2 and an A / D conversion unit 112-2. The input unit 111-2 inputs an analog signal of the voltage of the power system of the reference electric station. The A / D conversion unit 112-2 converts the analog signal of the voltage input to the input unit 111-2 into digital data. The communication unit 113-2 transmits the digital data converted by the A / D conversion unit 112-2 to the power system monitoring device 100B via a communication network such as the Internet or LAN. The communication unit 113-2 is, for example, a communication interface such as a NIC or a wireless communication module.

The power system monitoring device 100B includes, for example, a phase angle detection unit 120B, a storage unit 130B, an arithmetic processing unit 140B, a control information output unit 150, and a communication unit 170. The communication unit 170 receives digital data of the respective voltages measured by the measuring devices 200-1 and 200-2.

The phase angle detection unit 120B detects the voltage phase of the monitored generator 10 and the voltage phase of the bus voltage of the reference electric station from the voltage information of the power system received by the communication unit 170. Further, the phase angle detection unit 120B stores the time-series information of the measurement result of the voltage phase of the bus bar voltage of the monitored generator 10 and the reference electric station at the second predetermined time in the storage unit 130B as the phase angle information 131B. ..

The calculation processing unit 140B includes, for example, a phase angle change amount calculation unit 141B and a step-out tendency determination unit 142B. The phase angle change amount calculation unit 141B has each phase angle change amount with respect to the reference waveform based on the detection results of the voltage phase of the monitored generator 10 and the voltage phase of the bus voltage of the reference electric station stored in the storage unit 130B. Calculate _{Δδ g1} and Δδ k1. Here, phase angle change amount △ [delta] _g1, and △ [delta] _k1, the phase angle variation △ theta is, for example, _{"△ δ g1 - △ δ k1 =} ∫Δθdt " relation holds.

FIG. 6 is a diagram for explaining _{the phase angle change amounts Δδ g1} and Δδ _{k1 of the third embodiment.} The horizontal axis of FIG. 6 indicates the time T, and the vertical axis indicates the cumulative value δ of the amount of change in the phase angle. _{Further, FIG. 6 shows the cumulative value δ g1} of the phase angle change amount of the bus voltage of the reference electric station with the passage of time _{and the cumulative value δ k1} of the phase angle change amount of the monitored generator 10.

_{The phase angle change amount calculation unit 141B includes the calculated phase angle change amount (Δδ K1} ) of the bus voltage of the reference electric station in the first predetermined time, and the phase angle change amount (Δδ K1) of the monitored generator 10 in the first predetermined time. _{Calculate Δδ g1} ). The calculation result is stored in the storage unit 130 as the phase angle change amount information 132B.

The step-out tendency determination unit 142B uses the phase angle change amounts Δδ _k1 and Δδ _g1 for each predetermined time to determine whether or not the difference (Δδ _{g1-Δδ k1) exceeds the threshold value.} Then, the step-out tendency determination unit 142B determines that the monitored generator 10 has a step-out tendency when the difference value exceeds the threshold value. In FIG. 6, the _{value of Δδ k1 set} to a constant value (zero) corresponds to the processing of the first embodiment.

As described above, the power system monitoring device 100A of the third embodiment has the same effect as that of the first embodiment, and also treats the voltage phase of the reference electric station as a reference waveform and monitors the bus voltage. Sampling between the measuring device 200 and the power system monitoring device 100B by calculating the difference in phase angle change using the phase difference of the voltage of the target generator 10 and determining the step-out tendency of the monitored generator. The phase difference determination can be performed without synchronization.

(Fourth Embodiment)
Next, a fourth embodiment of the power system monitoring device will be described. In the following, the same names and reference numerals will be used for configurations having the same functions as the monitoring system 3 of the third embodiment, and specific description thereof will be omitted.

FIG. 7 is a configuration diagram of a monitoring system 4 including the power system monitoring device 100C of the fourth embodiment. The monitoring system 4 of FIG. 7 includes, for example, a generator 10 to be monitored, a transformer 20, a power system monitoring device 100C, and measuring devices 200A-1 and 200A-2. Compared with the monitoring system 3 in the third embodiment, the monitoring system 4 includes the accident detection units 114-1 and 114-2 in the measuring devices 200A-1 and 200A-2, and the accident detection unit 114-1. The processing of the power system monitoring device 100C by providing 114-2 is different. Therefore, in the following, the accident detection units 114-1 and 114-2 will be mainly described.

The accident detection units 114-1 and 114-2 detect the occurrence of a system accident by using the voltage information acquired by the analog input units 110-1 and 110-2, respectively. The communication unit 113 transmits digital voltage data and an accident detection signal by the accident detection unit 114 to the power system monitoring device 100C.

The power system monitoring device 100C includes, for example, a phase angle detection unit 120C, a storage unit 130C, an arithmetic processing unit 140C, a control information output unit 150, and a communication unit 170C. The phase angle detection unit 120C calculates the voltage phase of the bus voltage of the monitored generator 10 and the reference electric station based on the voltage information of the power system obtained from the communication unit 170C, and also measures the measuring devices 200-1 and 200. The occurrence of a system accident is detected based on the accident detection signal received from -2. For example, the phase angle detection unit 120C detects that a system accident has occurred when an accident detection signal is received from at least one of the measuring devices 200-1 and 200-2. The phase angle change amount calculation unit 141C calculates the phase angle change amount for the first predetermined time with reference to the time when the accident detection signal is received.

FIG. 8 is a diagram for explaining _{the phase angle change amounts Δδ k2} and Δδ _{g2 of the fourth embodiment.} The horizontal axis of FIG. 8 indicates the time T, and the vertical axis indicates the cumulative phase angle value δ. _{Further, FIG. 8 shows the cumulative value δ g2} of the phase angle change amount of the bus voltage of the reference electric station _{and the cumulative value δ k2} of the phase angle change amount of the monitored generator 10. The phase angle change amount calculation unit 141C is the first from the time when the system accident occurs, based on the value of the phase angle change amount for each predetermined time stored in the phase angle change amount information 132C with reference to the time when the accident occurs based on the accident detection signal. The amount of change in phase angle up to a predetermined time _{Δδ g2} and Δδ _k2 are calculated. Also, out-of-step tendency determination unit 142C, the phase angle variation △ δ _g2, △ δ _k2 difference - determines whether (△ δ _g2 △ δ _k2) exceeds a threshold value. Then, the step-out tendency determination unit 142C determines that the monitored generator 10 has a step-out tendency when the difference exceeds the threshold value.

As described above, the power system monitoring device 100C of the fourth embodiment has the same effect as that of the third embodiment, and it is possible to target only the step-out due to the system accident, which is gradual. Even in the case of step-out due to a large phase change, if the threshold value is exceeded, it can be determined that there is a tendency to step-out, and a control command or the like can be output.

(Fifth Embodiment)
Next, a fifth embodiment of the power system monitoring device will be described. In the following, the same names and reference numerals will be used for configurations having the same functions as the monitoring system 3 of the third embodiment, and specific description thereof will be omitted.

FIG. 9 is a configuration diagram of a monitoring system 4 including the power system monitoring device 100D of the fifth embodiment. The monitoring system 5 of FIG. 9 includes, for example, a monitored generator 10, a transformer 20, a power system monitoring device 100D, measuring devices 200A-1, 200A-2, and a server device 300. The monitoring system 5 is different from the monitoring system 4 in the fourth embodiment in that it includes the server device 300 and the configuration of the arithmetic processing unit 140D. Therefore, in the following, the server device 300 and the arithmetic processing unit 140D will be mainly described.

The server device 300 includes, for example, a communication unit 310, a system power supply information acquisition unit 320, and a storage unit 330. The communication unit 310 communicates with the measuring devices 200-1 and 200-2. The communication unit 310 acquires measurement information from, for example, measuring devices 200-1 and 200-2. Further, the communication unit 310 transmits the power supply information 331 to the power system monitoring device 100D. The communication unit 310 is, for example, a communication interface such as a NIC or a wireless communication module.

The system power supply information acquisition unit 320 acquires power supply information for each system measured by the measuring device 200 from the information received by the communication unit 310. The power supply information is, for example, a digital voltage of the monitored generator 10 and the reference electric station acquired from the measuring devices 200-1 and 200-2 in a situation where the generator connected to the power system does not tend to be out of step. It is data. This power supply information is power supply information before a system accident occurs. The acquired power supply information is stored in the storage unit 330 as power supply information 331. Further, the system power supply information acquisition unit 320 may calculate the phase difference information between the monitored generator 10 and the reference electric station, and store the calculation result in the storage unit 330.

The storage unit 330 is realized by, for example, a non-volatile storage medium such as a ROM, a flash memory, an HDD, or an SD card, and a volatile storage medium such as a RAM or a register. The storage unit 330 stores various information such as power supply information 331, for example.

The power system monitoring device 100D includes, for example, a phase angle detection unit 120D, a storage unit 130D, an arithmetic processing unit 140D, a control information output unit 150, and a communication unit 170D. The storage unit 130D includes phase angle information 131D, phase angle change amount information 132D, and power supply information 133.

The communication unit 170D receives digital voltage data from the measuring devices 200-1 and 200-2. Further, the communication unit 170D receives the power supply information 331 of the measuring devices 200-1 and 200-2 from the server device 300. The communication unit 170 stores the received power supply information as the power supply information 133 in the storage unit 130D. Further, the communication unit 170D may receive the phase difference information between the monitored generator 10 and the reference electric station from the server device 300.

The phase angle detection unit 120D calculates the voltage phase of the bus voltage of the monitored generator 10 and the reference electric station, and detects the occurrence of a system accident based on the accident detection signal received from the measuring device. For example, the phase angle detection unit 120D detects that a system accident has occurred when an accident detection signal is received from at least one of the measuring devices 200-1 and 200-2.

Further, the calculation processing unit 140D includes, for example, a phase angle change amount calculation unit 141D, a step-out tendency determination unit 142D, a pre-accident phase difference calculation unit 143, an accident detection phase angle detection unit 144, and a calculation timing correction unit. It includes 145.

The pre-accident phase difference calculation unit 143 has the voltage phase of the bus voltage of the reference electric station so that the phase difference is equal to the phase difference due to the power supply information under the condition that the generator stored in the storage unit 130D does not tend to step out. And the times t1 and t2 for correcting the timing of the voltage phase of the monitored generator 10 are calculated. For example, the pre-accident phase difference calculation unit 143 calculates the difference between the voltage phase of the bus voltage of the reference electric station and the voltage phase of the monitored generator 10 from the time when the system accident is detected to a predetermined time before. Further, when the pre-accident phase difference calculation unit 143 detects a system accident from the accident detection unit 114 by the accident detection signal, the voltage phase difference of the power supply information stored in the power supply information 133 of the storage unit 130D and the time when the accident is detected. Therefore, within one window length, the difference between the voltage phase of the bus bar voltage of the reference electric station (Δδ _{k (t1)} ) and the voltage phase of the monitored generator 10 (δ _{g (t2) ) (δ g (t2)} − △ Calculate t1 and t2 in which δ _{k (t1)) are almost equal.}

After the accident detection unit 114 detects the system accident, the phase angle detection unit 144 at the time of accident detection determines the bus voltage of the reference electric station based on the measurement result of the voltage phase stored in the phase angle information 131D of the storage unit 130D. The phase angle (δ _{g (t)} ) at the time of the occurrence of the system accident and the phase angle (δ _{k (t)} ) at the time of the occurrence of the system accident of the monitored generator 10 are calculated.

The calculation timing correction unit 145 uses t1 and t2 calculated by the pre-accident phase difference calculation unit 143 to measure the voltage phase stored in the phase angle information 131D, and sets the time at the time of the accident to t0. Occasionally, the timing of the voltage phase of the bus voltage of the reference electric station is delayed by t1, and the timing of the voltage phase of the monitored generator 10 is delayed by t2. Further, the calculation timing correction unit 145 outputs the phase angle whose timing is delayed to the phase angle change amount calculation unit 141D as the latest phase.

The phase angle change amount calculation unit 141D calculates the phase angle change amount Δδ _k and Δδ _g using the phase angle input from the calculation timing correction unit 145. Out-of-step tendency determination unit 142D, the phase angle variation stored in the phase angle variation information 132D of the storage unit 130D △ [delta] _k, using △ [delta] _g, the difference _{(△ δ g - △ δ k} ) is the threshold Judge whether or not it exceeds.

FIG. 10 is a diagram for explaining _{the phase angle change amounts Δδ k} and Δδ _{g of the fifth embodiment.} The horizontal axis of FIG. 10 indicates the time T, and the vertical axis represents the phase angle change amount δ. The step-out tendency determination unit 142D has a difference (Δδ _g − Δδ _k ) of the _{amount of change in phase angle Δδ k} and Δδ _g after the lapse of the first predetermined time, based on the time when the accident occurs (t = 0). When it is equal to or more than the threshold value, it is determined that the monitored generator 10 tends to be out of phase.

As described above, according to the power system monitoring device 100D of the fifth embodiment, the same effect as that of the fourth embodiment is obtained, and the reference electric station and the monitoring target are monitored by using the phase difference obtained from the power supply information. By correcting the time difference at the timing of starting the voltage phase measurement of the generator and calculating the corrected phase angle change amount, it is possible to reduce the time error of the step-out tendency determination. Thereby, the accuracy of the phase difference detection can be improved. The above-mentioned first to fifth embodiments may be combined with a part or all of the other embodiments.

According to at least one embodiment described above, the voltage measured by the analog input unit 110 and the phase angle detection unit 120 for measuring the voltage phase of the monitored generator 10 and the analog input unit 110 and the phase angle detection unit 120. A storage unit 130 that stores the phase measurement result, a phase angle change amount calculation unit 141 that calculates the phase angle change amount in the first predetermined time based on the voltage phase measurement result stored in the storage unit 130, and a phase. Synchronous control is performed by having a step-out tendency determination unit 142 that determines whether or not the monitored generator 10 has a step-out tendency based on the phase angle change amount calculated by the angle change amount calculation unit 141. It is not necessary and the step-out tendency of the generator can be determined.

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 modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

1 to 5 ... Monitoring system, 10 ... Monitored generator, 20 ... Transformer, 100 ... Power system monitoring device, 110 ... Analog input unit, 111 ... Input unit, 112 ... A / D conversion unit, 113, 170, 310 ... Communication unit, 114, 160 ... Accident detection unit, 120 ... Phase angle detection unit, 130, 330 ... Storage unit, 131 ... Phase angle information, 132 ... Phase angle change amount information, 133 ... Power supply information, 140 ... Arithmetic processing unit , 141 ... Phase angle change amount calculation unit, 142 ... Step-out tendency determination unit, 143 ... Pre-accident phase difference calculation unit, 144 ... Accident detection phase angle detection unit, 145 ... Calculation timing correction unit, 150 ... Control information output unit , 200 ... Measuring device, 300 ... Server device, 320 ... System power supply information acquisition unit

Claims (10)

A measuring unit that measures the voltage phase of the generator to be monitored,
A storage unit that stores the measurement result of the voltage phase measured by the measurement unit, and a storage unit.
A phase angle change amount calculation unit that calculates the phase angle change amount in the first predetermined time based on the voltage phase measurement result stored in the storage unit.
Based on the phase angle change amount calculated by the phase angle variation calculating unit, Bei give a, a determination section for determining whether or not the generator is in the step-out tends,
The phase angle change amount calculation unit acquires the phase angle change amount in the first predetermined time by repeatedly calculating and accumulating the phase angle change amount in the second predetermined time shorter than the first predetermined time.
Power system monitoring devices. The determination unit determines that the generator tends to step out when the phase angle change amount calculated by the phase angle change amount calculation unit exceeds the threshold value.
The power system monitoring device according to claim 1. An accident detection unit for detecting a system accident is further provided by using the measurement result of the voltage phase measured by the measurement unit.
The phase angle change amount calculation unit calculates the phase angle change amount in the first predetermined time based on the time when a system accident is detected by the accident detection unit.
The power system monitoring device according to claim 1 or 2. When the difference between the amount of change in the phase angle of the reference waveform and the amount of change in the phase waveform measured by the measuring unit in the first predetermined time is equal to or greater than the threshold value, the determination unit tends to cause the generator to step out. Judged to be in
The power system monitoring device according to any one of claims 1 to 3. The phase angle change amount calculation unit treats a preset ideal voltage phase waveform as the reference waveform.
The power system monitoring device according to claim 4. The measuring unit measures the voltage phase of the generator and the voltage phase of the reference electric station, and measures the voltage phase.
The storage unit stores the measurement results of the voltage phase of the generator and the voltage phase of the electric station.
The phase angle change amount calculation unit treats the voltage phase of the electric station stored in the storage unit as the reference waveform.
The power system monitoring device according to claim 4. An accident detection unit for detecting a system accident is further provided by using the measurement result of the voltage phase measured by the measurement unit.
The phase angle change amount calculation unit treats the voltage phase of the voltage phase of the electric station as the reference waveform for the first predetermined time from the time when the system accident is detected by the accident detection unit.
The power system monitoring device according to claim 6. A pre-accident phase difference calculation unit that calculates the difference between the voltage phase of the bus voltage of the electric station and the voltage phase of the generator a predetermined time before the detection of the system accident.
The phase angle at the time of the occurrence of a system accident of the bus voltage of the electric station, the phase angle detection unit at the time of accident detection for detecting the phase angle at the time of the occurrence of the system accident of the generator, and the phase angle detection unit.
The difference between the voltage phase of the bus voltage of the electric station before a predetermined time obtained by the phase difference calculation unit before the accident and the voltage phase of the generator, and the system of the bus voltage obtained by the phase angle detection unit at the time of accident detection. A calculation timing correction unit for correcting the timing of starting the calculation in the phase angle change amount calculation unit based on the phase angle at the time of the accident occurrence and the phase angle at the time of the system accident of the generator is further provided.
The power system monitoring device according to claim 7. A control information output unit for outputting control information to the generator regarding the determination result by the determination unit is further provided.
The power system monitoring device according to any one of claims 1 to 8. The computer
Measure the voltage phase of the generator to be monitored and
The measured measurement result of the voltage phase is stored in the storage unit, and the measurement result is stored.
Based on the measurement result of the voltage phase stored in the storage unit, the amount of phase angle change in the first predetermined time is calculated.
Based on the calculated phase angle change amount, it is determined whether or not the generator tends to step out .
Further, the phase angle change amount in the first predetermined time is acquired by repeatedly calculating and accumulating the phase angle change amount in the second predetermined time shorter than the first predetermined time.
Power system monitoring method.

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