JP6787765B2 - Distribution system voltage regulator, voltage regulator system, voltage regulator method and distribution equipment design support system - Google Patents

Description

The present invention relates to a voltage adjustment device, a voltage adjustment system, a voltage adjustment method and a distribution equipment design support system of a distribution system, and solar power generation is particularly performed when the output of a solar power generation device installed in the distribution system is suppressed. The present invention relates to a voltage adjustment device, a voltage adjustment system, a voltage adjustment method, and a distribution equipment design support system of a distribution system that enable control of lowering the voltage at a device installation point.

In recent years, the grid interconnection of photovoltaic power generation devices has increased in distribution systems, but in distribution systems, there is a phenomenon that the voltage at the installation point of photovoltaic power generation devices rises as the amount of power generated by the photovoltaic power generation devices increases. .. In order to avoid this, the photovoltaic power generation device is provided with a function of suppressing the amount of power generated by the photovoltaic power generation device when the own terminal voltage rises above the specified voltage. This function limits the amount of power generated by the photovoltaic power generation device.

On the other hand, the voltage of the distribution system can be adjusted by tap changer of a transformer (LRT: Road Radio Control Transformer) installed in a distribution substation or an automatic voltage regulator (SVR:) installed on a distribution line. It is controlled by tap switching such as Step Voltage Transformer).

In order to avoid the suppression of the amount of power generated by the photovoltaic power generation device described above, the voltage of the distribution system is adjusted by the voltage regulator (tap changer transformer LRT at load or automatic voltage regulator SVR) to suppress the output. It is important to avoid. For that purpose, it is necessary to appropriately perform tap control according to the amount of power generated by the photovoltaic power generation device.

The following methods are known as control methods for voltage regulators (load tap changer transformer LRT and automatic voltage regulator SVR).

For example, in a normal automatic voltage regulator SVR, a method of determining a tap value from a secondary voltage at its own end, a passing current, and a power factor is known in Non-Patent Document 1.

Patent Document 1 describes the voltage fluctuation range obtained by adding the voltage rise width from the transmission voltage of the voltage adjusting transformer to the voltage at the highest voltage point and the voltage fall width from the transmission voltage of the transformer to the voltage at the lowest voltage point. A control method for selecting the transmission voltage of the voltage regulator so that the center value becomes a specified value is shown.

In addition, the secondary side voltage (tap value) of the automatic voltage regulator SVR is adjusted according to the amount of power generated by the photovoltaic power generation device in the system, and the amount of power generated by the photovoltaic power generation device at that time is automatically adjusted to that of the photovoltaic power generation device. It is known to infer from communication between voltage regulators SVR or pyranometer information.

The detailed configuration of the automatic voltage regulator SVR is also described in detail in Non-Patent Document 1. A specific calculation method for multiple regression analysis is also known.

JP-A-2009-240038

"Advances and Applications of Line Voltage Regulators" Modern Power Distribution Technology, Denki Shoin, pp. 128-134 (1972)

In the method of determining the tap value from the secondary side voltage of the self-end, the passing current, and the power factor according to Non-Patent Document 1 described above, control in consideration of voltage rise and output suppression by the photovoltaic power generation device is not assumed. Therefore, the automatic voltage regulator SVR has a problem that the voltage cannot be adjusted and the output suppression of the photovoltaic power generation device cannot be avoided in the situation where the voltage rise is avoided by the output suppression of the photovoltaic power generation device.

Further, in the method described in Patent Document 1, in a situation where the voltage rise is avoided by suppressing the output of the photovoltaic power generation device, it is not possible to properly set the line voltage drop compensator of the voltage regulator, and the sun There is a problem that the output suppression of photovoltaic power generation cannot be avoided.

Furthermore, with the expansion of the interconnection of the mega solar to the end of the distribution system and the interconnection of the photovoltaic power generation equipment of general consumers to the low voltage side, the terminal voltage of the photovoltaic power generation equipment rises, and the sunlight of a specific customer There is a problem that the output of the power generation device is suppressed and the loss of power selling opportunity occurs unequally.

From the above, the present invention enables control such that when the output of the photovoltaic power generation device installed in the distribution system is suppressed, the voltage at the installation point of the photovoltaic power generation device is lowered to eliminate the output suppression. , Provides a voltage regulator for a distribution system, a voltage regulator system, a voltage regulator method, and a distribution equipment design support system.

From the above, in the present invention, a transformer with a tap is installed in a distribution system provided with a plurality of photovoltaic power generation devices having an output suppression function, and the tap is adjusted so that the voltage at a virtual point of the distribution system is set as a set voltage. It is a voltage regulator of a distribution system equipped with a device, and it obtains and outputs the output suppression amount of the photovoltaic power generation device by the output suppression function and the photovoltaic power generation device output amount calculation means for calculating the output amount of the photovoltaic power generation device. Power distribution including photovoltaic power generation equipment ranked by multiple regression analysis of the passing current of the tapped transformer and the output suppression amount estimation and ranking means of the photovoltaic power generation equipment that ranks the photovoltaic power generation equipment according to the suppression amount. An analysis means that determines the position of the center of gravity of the system as a virtual point and determines a set value that represents the distance from the tapped transformer to the virtual point, and a line voltage drop compensation circuit that estimates the voltage at the virtual point using the set value. It is a voltage adjusting device for a power distribution system, which is provided with a tap control device for controlling a voltage at a virtual point to a set voltage.

Further, in the present invention, a voltage adjustment system for a distribution system including a transformer with a tap that adjusts the tap so that the voltage at a virtual point of the distribution system is set as a set voltage, and a plurality of solar power generation devices having an output suppression function. Therefore, for a plurality of solar power generation devices, the output suppression amount is estimated based on the output amount calculation means for calculating the output amount and the output amount obtained for each solar power generation device, and the output suppression amount is calculated. The position of the center of gravity of the distribution system including the extracted solar power generation device is determined as a virtual point by the ranking means that sorts according to, and the multiple regression analysis of the passing current of the tapped transformer, and the tapped transformer is virtualized. Line voltage drop compensation that estimates the voltage at a virtual point using a distribution equipment design support device equipped with an analysis means for determining a set value representing the distance to a point and the set value determined by the distribution equipment design support device. It is a voltage adjustment system for a distribution system including a circuit and a voltage adjustment device provided with a tap control device that controls a voltage at a virtual point to a set voltage.

Further, in the present invention, a transformer with a tap is provided, which is installed in a distribution system equipped with a plurality of photovoltaic power generation devices having an output suppression function and adjusts a tap so that the voltage at a virtual point of the distribution system is set as a set voltage. This is a method for adjusting the voltage of the distribution system. The output amount of a plurality of photovoltaic power generation devices is estimated, and the photovoltaic power generation devices are extracted and extracted in descending order of the output suppression amount obtained for each photovoltaic power generation device. For the distribution system including the photovoltaic power generation device, the output center of gravity position of the photovoltaic power generation device is determined as a virtual point, and the voltage at the virtual point is controlled to the set voltage, which is a voltage adjustment method of the distribution system. Is.

Further, the present invention is provided with a transformer with a tap which is installed in a distribution system equipped with a plurality of photovoltaic power generation devices having an output suppression function and adjusts a tap so that the voltage at a virtual point of the distribution system is set as a set voltage. This is a voltage adjustment method for the distribution system. For a photovoltaic power generation device that estimates the amount of output suppression by the output suppression function for multiple photovoltaic power generation devices and suppresses the output, the position of the output center of gravity of the photovoltaic power generation device is virtual. It is a voltage adjustment method for a distribution system, which is defined as a point and is characterized in that the voltage at a virtual point is controlled to a set voltage.

Further, the present invention is provided with a transformer with a tap, which is installed in a distribution system equipped with a plurality of solar power generation devices having an output suppression function and adjusts a tap so that the voltage at a virtual point of the distribution system is set as a set voltage. A distribution facility design support device for a distribution system that is applied to a distribution system and gives a set value for estimating the voltage at a virtual point, and is a solar power generation device output amount calculation means for calculating the output amount of the solar power generation device. , Obtaining the output suppression amount of the solar power generation device by the output suppression function, and ranking the solar power generation device according to the output suppression amount. Output suppression amount estimation and ranking means of the solar power generation device, and the passing current of the tapped transformer. By the multiple regression analysis of, the position of the center of gravity of the distribution system including the ranked solar power generation device is determined as a virtual point, and the set value representing the distance from the tapped transformer to the virtual point is determined by the analysis means and analysis means. It is a distribution equipment design support device for a distribution system, which is characterized by being provided with an output means for giving a obtained settling value to a transformer with a tap.

According to the voltage adjusting device and the control method of the distribution system of the present invention, the voltage deviation of the distribution system can be reduced even in a system in which a large amount of photovoltaic power generation or the like is introduced. There is an effect that the loss of power selling opportunity can be reduced by reducing the output suppression amount of a specific photovoltaic power generation.

In addition, other effects of the present invention will be described in the specification.

The figure which shows the whole structure of the distribution equipment design support system which concerns on this invention. Explanatory drawing which shows the configuration example of a general distribution system and a voltage adjustment system. The figure which shows the structure of the tap control device of the automatic voltage regulator SVR. A processing flow diagram that avoids suppression of photovoltaic power generation output by tap control operation. The figure which shows the data flow of a measuring means and a distribution equipment design support system. The figure which shows the structure in the case of configuring the facility design support system 400 by a computer. The figure which shows the processing flow of the PV output amount calculation means of a photovoltaic power generation apparatus. The figure which shows the processing flow of the PV output suppression estimation and ranking means of a photovoltaic power generation apparatus. The figure which shows the processing flow of the multiple regression analysis means with SVR passing current. The figure which shows the geometric image of α and β obtained in FIG. The figure which shows the Example which provided the SVR set value determination means 400A in the automatic voltage regulator SVR. It is a figure which shows the area composition example of the area of the distribution system extended in a dendritic shape via an automatic voltage regulator SVR. The figure which shows only the photovoltaic power generation apparatus PV which correlates with the output suppression in the photovoltaic power generation apparatus PV.

Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 2 is a diagram showing a configuration example of a general distribution system and a voltage adjustment system. A typical distribution system 100 shown in FIG. 2 is a node (bus) 120, a distribution line 140 connecting them, a load 150 connected to the node 120, a photovoltaic power generation device PV, and a sensor installed in the distribution line 140. It is composed of 170, a distribution substation 110, and the like. Here, the left side in the drawing where the distribution substation 110 is located is the sending side of the feeder, and the right side is the terminal side of the feeder.

The automatic voltage adjusting device 300 is a voltage adjusting device that is installed in series with the line 140 and adjusts the line voltage. Examples of the automatic voltage regulator 300 include a load tap changer transformer LRT and an automatic voltage regulator SVR, but here, an example in which the automatic voltage regulator SVR is arranged as the voltage regulator 300 is shown. The automatic voltage regulator SVR may be a load tap switching transformer (LRT: Road Radio Control Transformer) in a distribution substation, but in FIG. 2, as illustrated by the automatic voltage regulator 300, for example, it is simple. A transformer 305 composed of a winding transformer and a tap changer, an automatic voltage regulator SVR provided with a control portion 310, a signal from a sensor 170 installed on a distribution line, and a distribution equipment design support system 400. The tap is operated using the motion settling value 350.

Further, in FIG. 2, reference numeral 400 denotes a power distribution equipment design support system, which appropriately obtains inputs from various measuring means 200 including a sensor 170 and gives an operation setting value 350 to the automatic voltage adjusting device 300. Although FIG. 2 shows a distribution system 100 having a simple configuration, in reality, automatic voltage adjusting devices 300 are appropriately provided in various places of a plurality of feeders, and the distribution equipment design support system 400 is provided with each automatic voltage adjusting device 300. On the other hand, the optimum operation settling value 350 at each installation location is determined and given.

As illustrated in FIG. 2, the voltage adjusting system in the present invention has an overall configuration including an automatic voltage adjusting device 300 and a power distribution equipment design support system 400, but in the embodiment of the present invention, the automatic voltage adjusting device 300 The function of the power distribution equipment design support system 400 illustrated in FIG. 1 may be included in itself and integrated as a voltage adjusting device.

FIG. 1 shows the overall configuration of the power distribution equipment design support system according to the present invention. Due to its internal processing, the distribution equipment design support system 400 has the active component Ir and the invalid component Ii (or the active power _PSVR and invalid) of the passing current of the automatic voltage regulator SVR from various measuring means 200 including the sensor 170. Electric power Q _SVR ), potential difference ΔV between the automatic voltage regulator SVR installation point and the solar power generation device PV installation point, the amount of solar radiation, etc. are acquired.

The power distribution facility design support system 400 is generally configured as a computer system, but when its function is expressed as a means, the photovoltaic power generation device output amount calculation means 440, the photovoltaic power generation device output suppression estimation and ranking means 460. , Automatic voltage regulator SVR passing current, multiple regression analysis means 480, database DB3, etc. In the database DB3, in addition to the measured values for each input time, information on the arrangement of the photovoltaic power generation device PV and the power generation capacity in the target distribution system, the load pattern, the information on the arrangement position of the automatic voltage regulator SVR, etc. It is remembered.

Specific functions of the photovoltaic power generation device output amount calculation means 440, the photovoltaic power generation device output suppression estimation and ranking means 460, and the automatic voltage regulator SVR passing current and multiple regression analysis means 480, which are the main functions of the distribution equipment design support system 400. The details of the processing will be described in detail with reference to the processing flows of FIGS. 7, 8 and 9, but the following is a very brief description.

First, the photovoltaic power generation device output amount calculation means 440 of FIG. 1 takes in the information of the database DB3 and calculates the output amount of the photovoltaic power generation device PV for each appropriate point. The photovoltaic power generation device output suppression estimation and ranking means 460 estimates the output suppression amount in the photovoltaic power generation device PV, sorts the output according to the output suppression amount, and uses the multiple regression analysis means 480 with the SVR passing current to perform SVR. The set value 350 is calculated and output to the outside, and the SVR set value 350 is set for the automatic voltage adjusting device 300.

On the other hand, the control portion of the automatic voltage adjusting device 300 on the side receiving the SVR set value 350 is a sensor 170 for measuring the amount of electricity in the distribution line and a tap control device 310 for controlling the tap of the transformer as shown in FIG. It is composed of. FIG. 3 shows a specific circuit configuration example of the transformer 305 according to the present invention and the control portion.

The concept of tap control will be described first with reference to FIG. 3, and then the relationship between the SVR set value 350 given by the distribution equipment design support system 400 and the line voltage drop compensation circuit LDC will be described. FIG. 3 shows a self-winding transformer 303 and a tap changer 302 which are main circuits of the automatic voltage adjusting device 300, and a tap control device 310 which is a control device.

The tap control device 310 includes a measuring unit 320, line voltage drop compensation circuits LDC1 and LDC2, a tap control device 340, databases DB1 and DB2, and is a tap changer for controlling the secondary voltage of the autotransformer 303 to a predetermined value. You are operating 302. Here, the database DB2 holds the SVR set value 350 given by the distribution facility design support system 400.

The databases DB1 and DB2 store various operation set values for executing tap control. These include parameters (voltage Vref, impedance R, X), dead band VE, timer time constant τ, operating time constant T, etc. for performing the line voltage drop compensation calculation (LDC calculation). The SVR set value 350 given to the database DB2 by the distribution equipment design support system 400 may include all of them, but at least impedances R and X are determined by processing in the distribution equipment design support system 400. is there.

A sensor CT for measuring the secondary side current Isvr of the distribution line and a sensor PT for measuring the secondary side voltage Vsvr are connected to the measuring unit 320 of the tap control device 310.

The line voltage drop compensation circuit LDC (LDC1, LDC2) detects that the secondary voltage Vsvr measured by the measuring unit 320 deviates from a predetermined limit value, and this state continues for a predetermined measurement time or longer. By doing so, the tap switching control is executed via the tap control device 340.

In the embodiment of FIG. 3, LDC1 and LDC2 are provided as the line voltage drop compensation circuit LDC. Of these, the line voltage drop compensation circuit LDC1 is an existing device, and the line voltage drop compensation circuit LDC2 is newly added. It is a device. Each line voltage drop compensation circuit LDC controls the voltage at the virtual point of the distribution system from the secondary side information of the automatic voltage regulator 300 within a predetermined range, but the line voltage drop compensation circuit LDC1 is a photovoltaic power generation device. While it does not have any countermeasure method for the problem in PV, the line voltage drop compensation circuit LDC2 is a countermeasure for the problem in the photovoltaic power generation device PV.

Further, with respect to the fact that the line voltage drop compensation circuit LDC includes LDC1 and LDC2, both settings may be configured so as to deal with the problem in the photovoltaic power generation device PV. When limiting the voltage within a predetermined range, the line voltage drop compensation circuits LDC1 and LDC2 can be used to determine the upper limit and the lower limit.

The present invention does not necessarily require two lines of the line voltage drop compensation circuit LDC, but when the two lines of the line voltage drop compensation circuit LDC are provided, the line voltage drop compensation circuit LDC1 is output by the solar power generation device PV. It can be said that the line voltage drop compensation circuit LDC2 is effective for tap control in fine weather, and is effective for tap control at night or in cloudy weather.

FIG. 4 shows the flow of calculation of the tap switching command 303 by the tap control device 340. According to the flowchart of FIG. 4, in the first processing step S1, the active power Psvr and the reactive power Qsvr are calculated from the secondary side current Isvr and the secondary side voltage Vsvr measured by the measuring unit 320. This process may be calculated by, for example, the line voltage drop compensation circuit LDC1 of the two line voltage drop compensation circuits LDC. The method of directly measuring the active power Psvr and the ineffective power Qsvr may be used. Further, instead of the active power Psvr and the reactive power Qsvr, the active component Ir and the reactive component Ii of the passing current of the automatic voltage regulator SVR may be obtained. In the following example, an example using the active ingredient Ir and the ineffective ingredient Ii will be described.

In the next processing step S2, the line voltage drop compensation circuit LDC1 reads the parameters (impedances R1 and X1 and voltage Vref1) shown in the database DB1 and executes the equation (1). By executing the equation (1) in the tap control device 310, the tap operation determination reference value Vs1 is calculated.
[Number 1]
Vs1 = Vref1 + R1 ・ Ir + X1 ・ Ii (1)
Here, the impedance (R1, X1) and the voltage Vref1 are parameters set in advance and stored in the database DB1, and Ir and Ii are the actual part of the passing current obtained from the measured passing current Isvr and the power factor cosθ. , The imaginary part of the passing current. R1 is a coefficient of the passing current of the automatic voltage regulator SVR with respect to the real part Ir, X1 is a coefficient of the passing current of the automatic voltage regulator SVR with respect to the imaginary part Ii, and Vref1 is a reference voltage.

The description of the processing step S2 in FIG. 4 describes an example of a calculation formula in which the terms R1 and Ir are obtained as the product of the active power Psvr and the coefficient AP1, and the terms X1 and Ii are obtained as the product of the ineffective power Qsvr and the coefficient Aq1. However, this leads to the same result regardless of which method is adopted.

Similarly, in the processing step S3, the line voltage drop compensation circuit LDC2 reads the parameters (R2 and X2 as impedances and voltage Vref2 as impedances) shown in the database DB2, and executes the equation (2). By executing the equation (2) in the tap control device 310, the tap operation determination reference value Vs2 is calculated.
[Number 2]
Vs2 = Vref2 + R2 ・ Ir + X2 ・ Ii (2)
Here, R2, X2, and Vref2 are preset parameters, and Ir and Ii are the real part of the passing current obtained from the measured passing current Isvr and the power factor cosθ, and the imaginary part of the passing current. R2 is a coefficient of the passing current of the automatic voltage regulator SVR with respect to the real part Ir, X2 is a coefficient of the passing current of the automatic voltage regulator SVR with respect to the imaginary part Ii, and Vref2 is a reference voltage.

Note that the description of the processing step S3 in FIG. 4 describes an example of a calculation formula in which the terms R2 and Ir are obtained as the product of the active power Psvr and the coefficient AP2, and the terms X2 and Ii are obtained as the product of the ineffective power Qsvr and the coefficient Aq2. However, this leads to the same result regardless of which method is adopted.

In the processing step S4, it is confirmed that the secondary side voltage Vsvr of the automatic voltage regulator SVR exceeds the predetermined positive / negative limit value ε1 with respect to the reference value Vs1 obtained by the equation (1), and is within the predetermined range. At a certain time (YES in the processing step S4), the process returns to the processing step S1 and the above processing is repeated.

When the secondary side voltage Vsvr of the automatic voltage regulator SVR exceeds a predetermined positive / negative limit value ε1 with respect to the reference value Vs1 (No in the processing step S4), the processing step S5 sets the time for satisfying the condition of the processing step S4. Accumulation is performed by a timer provided in the tap control device, a tap switching command is issued when the value exceeds Tsvr1 in the processing step S6, and Tsvr1 is reset in the processing step S7 after the tap switching.

The above processing for the result of equation (1) is similarly executed for the result of equation (2). This processing portion corresponds to the processing steps S8 to S11 of FIG.

Specifically, in the processing step S8, it is confirmed that the secondary side voltage Vsvr of the automatic voltage regulator SVR exceeds a predetermined positive / negative limit value ε2 with respect to the reference value Vs2 obtained by the equation (2). When the voltage is within the predetermined range (YES in the processing step S8), the process returns to the processing step S1 and the above processing is repeated.

When the secondary voltage Vsvr of the automatic voltage regulator SVR exceeds a predetermined positive / negative limit value ε2 with respect to the reference value Vs2 (No in the processing step S8), the processing step S9 sets the time for satisfying the condition of the processing step S8. A timer provided in the tap control device integrates, and in the processing step S10, a tap switching command is issued when the value exceeds Tsvr2, and after the tap switching, Tsvr2 is reset in the processing step S11.

According to the above processing judgment, when the secondary side voltage Vsvr of the automatic voltage regulator SVR is smaller than the reference value Vs1 by a constant value ε1 or more for a certain period of time (for example, Tsvr 1 second), the automatic voltage regulator SVR The tap 302 is changed in the upward direction to increase the secondary voltage. On the contrary, when a certain period of time elapses in a state where the secondary side voltage Vsvr of the automatic voltage regulator SVR is larger than this reference value Vs1 by a constant value ε1 or more, the tap 302 of the automatic voltage regulator SVR is changed in the downward direction to the secondary side. It operates such as lowering the voltage.

Similarly, when the secondary side voltage Vsvr of the automatic voltage regulator SVR is smaller than the reference value Vs2 by a constant value ε2 or more for a certain period of time (for example, Tsvr 2 seconds), the tap 302 of the automatic voltage regulator SVR is raised. Change direction and raise the secondary voltage. On the contrary, when a certain period of time elapses in a state where the secondary side voltage Vsvr of the automatic voltage regulator SVR is larger than this reference value Vs2 by a constant value ε2 or more, the tap 302 of the automatic voltage regulator SVR is changed in the downward direction to the secondary side. It operates such as lowering the voltage.

FIG. 5 shows the relationship between the power distribution equipment design support system 400 and various measuring means 200. The active component Ir and the ineffective component Ii of the passing current of the automatic voltage regulator SVR are measured by the measuring unit 320 (see FIG. 3) in the automatic voltage regulator SVR, and are measured from the slave station 190 via the dedicated line 191. Acquired by the distribution equipment design support system 400. Further, regarding the terminal voltage of the photovoltaic power generation device PV, the voltage from the voltmeter 180 is acquired from the slave station 190 to the distribution facility design support system 400 via the dedicated line 191. The amount of solar radiation is also acquired from the slave station 190 to the distribution facility design support system 400 via the dedicated line 191 in the pyranometer 185 installed near the distribution system. If the pyranometer 185 is not installed, the amount of solar radiation in the area is obtained from the solar radiation measurement data from the Japan Meteorological Agency.

FIG. 6 shows a configuration example when the equipment design support system 400 is configured by a computer. The facility design support system 400 includes a display device 11 that displays calculation results obtained as a result of various means, an input means 12 for receiving input from the system user, a CPU 13 for executing various means, and a communication means 14. A database that stores RAM15 for holding the calculation process, data groups that make up the distribution system (target distribution system, solar radiation measurement values, PV layout / capacity of solar power generation equipment, load pattern, SVR layout), and DB3 and LDC parameters It is composed of databases DB1 and DB2 for storing.

Next, the specific processing contents in the facility design support system 400 will be described in order.

First, FIG. 7 shows a processing flow of the photovoltaic power generation device output amount calculation means 440. The photovoltaic power generation device output amount calculation means 440 is composed of 440A and 440B.

Normally, as a function of the power conditioner of the photovoltaic power generation device PV, when the terminal voltage of the photovoltaic power generation device PV becomes 109 V or more in a low voltage distribution system, for example, the output is reduced by operating the PV terminal of the photovoltaic power generation device. Suppress the voltage to 109V or less.

Therefore, in the first processing of the photovoltaic power generation device output amount calculation means 440A, it is necessary to calculate the tidal current under the condition that the photovoltaic power generation device PV in the target distribution system does not suppress the output in the processing step S701. , Set the photovoltaic power generation device output suppression release mode. In the photovoltaic power generation device output suppression release mode, the photovoltaic power generation device PV outputs an output determined by the amount of solar radiation according to its own rated capacity without limitation. This makes it possible to find data that correlates with the terminal voltage of the PV of the photovoltaic power generation device.

Although the details will be described later, another photovoltaic power generation device output amount calculation means 440B sets the photovoltaic power generation device output suppression mode. Therefore, the photovoltaic power generation device output amount calculation means 440B does not execute the processing step S701, and all other processes are the same as those of the photovoltaic power generation device output amount calculation means 440A. In the photovoltaic power generation device output suppression mode, the photovoltaic power generation device PV suppresses the output according to the function of the power conditioner of the photovoltaic power generation device PV. For example, when the terminal voltage of the PV of the photovoltaic power generation device becomes a low voltage of 109V or more, the PV terminal voltage of the photovoltaic power generation device is controlled to 109V or less by operating to reduce the output.

Although the conclusion comes first, by finding the difference between the two photovoltaic power generation device output amount calculation means 440A and 440B, the output suppression timing and output suppression amount can be obtained for each photovoltaic power generation device PV. Become.

In the processing step S702, the target power distribution system, the amount of solar radiation, the arrangement / capacity of the PV of the photovoltaic power generation device, the load pattern, and the SVR arrangement data are read from the database DB3.

In the processing step S703, the output pattern of the photovoltaic power generation device, which is the time-series data of the generated power of the photovoltaic power generation device PV, is calculated from the arrangement, capacity, and amount of solar radiation of the photovoltaic power generation device PV in the obtained target system.

In the subsequent processing, the process of calculating the tidal current for each time cross section is started, so that the process is first initialized at time t = 0 in the process step S704.

In the process step S705, an arbitrary time t after initialization is compared with the preset maximum time Tmax, and if the time t <maximum time Tmax is Yes, the process proceeds to the process of the process step S706. If No, the process as the photovoltaic power generation device output amount calculation means 440 ends, and the process of the photovoltaic power generation device output suppression estimation and ranking means 460 shown in FIG. 8 is started.

In the processing step S706, the tidal current is calculated from the load pattern corresponding to the node 120 in the target distribution system and the output pattern of the photovoltaic power generation device by a method such as the BackwardForwardSweep method in the case of a radial system, and the node voltage is calculated.

In the process step S707, all the node numbers and node voltages in the target distribution system at the time t are in the format of (time t, node number, node voltage) and output to the power flow calculation result 422.

After that, in the processing step S708, the time t is updated by t + Δt (where Δt: time step width (seconds)), and the process transitions to the processing step S705.

In FIG. 7, the other photovoltaic power generation device output amount calculation means 440B also executes the same processing as the photovoltaic power generation device output amount calculation means 440A, and finally the photovoltaic power generation device output amount calculation means 440B and the photovoltaic power generation. The output difference of the device output amount calculation means 440A is obtained.

As shown in the lower part of FIG. 7, the processing result of the photovoltaic power generation device output amount calculation means 440A has the time from 6:00 am to 6:00 pm on the horizontal axis and the output amount PV1 of each photovoltaic power generation device on the vertical axis. , PV2, PV3 ... Can be expressed as a characteristic showing the maximum output according to the rated output according to the amount of solar radiation over time.

Similarly, the processing result of the photovoltaic power generation device output amount calculation means 440B has the time from 6:00 am to 6:00 pm on the horizontal axis and the output amount PV1', PV2', PV3', on the vertical axis. Although it can be shown by taking, it can be shown as a characteristic shown as a variable output that is appropriately suppressed according to the amount of solar radiation over time because the output suppression is functioning.

As the difference between the two, a function as illustrated in the lower left of FIG. 7 is required as a function of the passage of time. For the difference in the output amount of the photovoltaic power generation device, ΔPV1, ΔPV2, ΔPV3, etc., the calculation conditions (including time t, node number, node voltage, etc.) are specified for each individual photovoltaic power generation device in a separate database or the like. , Recorded as a time-series amount of change.

FIG. 8 shows the processing of the photovoltaic power generation device output suppression estimation and ranking means 460. In the first processing step S801, the automatic voltage regulator SVR of the target distribution system is selected as the setting target.

In the processing step S802, among the photovoltaic power generation device PVs connected to the feeder in which the selected automatic voltage regulator SVR is installed, among the photovoltaic power generation device PVs exceeding the upper limit of the output suppression of the photovoltaic power generation device. , The photovoltaic power generation device PV is rearranged in descending order of the PV output suppression amount (kWh) of the photovoltaic power generation device. At the time of this processing, the data of the difference ΔPV1, ΔPV2, ΔPV3 ... Of the output amount of the photovoltaic power generation device described above is referred to.

Next, in the processing step S803, the photovoltaic power generation device PVi is selected in descending order of the amount of suppression of the output of the photovoltaic power generation device. The reason for this is that the photovoltaic power generation device PV, which has a large amount of suppression of the output of the photovoltaic power generation device, is considered to miss the opportunity to sell power most. Further, in the processing step S804, the time series data Vsvrt of the SVR secondary side voltage is read, and further, in the processing step S805, the time series data of the photovoltaic power generation device terminal voltage Vpvit is read.

In the processing step S806, the potential difference ΔVi = Vpvi-Vsvri between the SVR secondary side voltage and the terminal voltage of the photovoltaic power generation device at the same time is calculated from the read time series data of Vsvrt and Vpvit.

Further, in the processing step S807, the correlation coefficient r between the potential difference ΔV and the terminal voltage of the photovoltaic power generation device is then calculated. The correlation coefficient can be calculated using Eq. (3). Here, X means the average of xi (i = 1, 2, ... n), Y means the average of yi (i = 1, 2, ... n), and sqrt () means the square root of the numerical value in parentheses.
[Equation 3]
n n n
r = Σ (xi-X) (yi-Y) / [sqrt (Σ (xi-X) ^ 2)) × sqrt ((ΣΣ)
i = 1 i = 1 i = 1

(Yi-Y) ^ 2))] (3)
In the processing step S808, the correlation coefficient r and its limit value rLimit are compared, and if the correlation coefficient r> the correlation coefficient limit value rLimit, there is a correlation between the potential difference ΔV and the solar power generation device terminal voltage. Is considered to exist, and a correlation flag is set for the data combination pattern selected in the processing step S809. Then, in the processing step S810, the photovoltaic power generation device PVi having the next largest output suppression amount of the photovoltaic power generation device is selected, and the transition to the processing step S811 occurs.

In the processing step S811, it is determined that the correlation determination processing in all the photovoltaic power generation devices PVi has been completed, and if the correlation coefficient has not been calculated for all the photovoltaic power generation devices PVi, the processing step. Move to S804 and execute the iterative process. If the correlation coefficient has been calculated for all the photovoltaic power generation devices PVi, the main process of the process step S811 is completed, and the process of the multiple regression analysis means 480 with the SVR passing current shown in FIG. 9 is started. ..

By the series of processing of FIG. 8, the plurality of photovoltaic power generation devices PVi are sorted in descending order of the output suppression amount, and the flagging (correlation) that there is a correlation between the potential difference ΔV and the photovoltaic power generation device terminal voltage. Yes flag == 1) is set. Therefore, the photovoltaic power generation device PV, which has a causal relationship that the voltage rise that is the cause of the output suppression is caused by the photovoltaic power generation device PV, is in a state where it can be easily extracted when used in the subsequent stage.

FIG. 9 shows the processing of the multiple regression analysis means 480 with the SVR passing current. First, the combination of the photovoltaic power generation device PVi is searched in the processing step S901, and the combination of the photovoltaic power generation device PVi having the correlation flag == 1 is extracted in the processing step S902. After finding the combination of the photovoltaic power generation device PVi having the correlation flag == 1, in the processing step S903, the potential difference ΔV at that time and the SVR passing currents Ir and Ii are subjected to multiple regression analysis calculation, and ΔV = α. Let α such that × Ir + β × Ii + ΔV0 be the set value R (Ω) of LDC2 of SVR.

Further, in the processing step S904, a multiple regression analysis is performed between the potential difference ΔV and the SVR passing current Ii at this time, and β such that ΔV = α × Ir + β × Ii + ΔV0 is set to the set value X (Ω) of LDC2 of the automatic voltage regulator SVR. ). In the processing step S905, if all the data combination patterns have not been searched, the process returns to the processing step S901. If all the data combination patterns have been searched, this process is terminated and the SVR set values R2 and X2 associated with the season / time zone are determined.

In short, the process of FIG. 9 determines the virtual points defined by the set values R and X of the LDC2 of the automatic voltage regulator SVR in consideration of the photovoltaic power generation device PV that causes output suppression. For example, if there are 100 photovoltaic power generation device PVs under the control of the automatic voltage regulator SVR, and 50 of them are photovoltaic power generation device PVs that frequently or cause large-scale output suppression, all 100 units are used. In contrast to the conventional one in which the virtual point is set in consideration of the above, in the present invention, the virtual point is set mainly by 50 photovoltaic power generation devices PV that cause output suppression.

Therefore, some methods for realizing the virtual point setting mainly for the photovoltaic power generation device PV that causes output suppression can be assumed, and the present invention may be any of them. These transformation methods are, for example, limited to the PV of the photovoltaic power generation device having a high degree of output suppression, or are determined by iterative calculation so as to increase the number of PV of the photovoltaic power generation device that can be saved from the output suppression as much as possible. It is conceivable that the weight coefficient of the PV of the photovoltaic power generation device that causes output suppression is increased to determine the virtual point.

FIG. 10 shows the geometric images of α and β obtained in FIG. FIG. 10 shows a three-dimensional plane determined by the active component Ir and the ineffective component Ii of the SVR passing current, and the potential difference ΔV between the SVR secondary side voltage and the terminal voltage of the photovoltaic power generation device. Here, when the potential difference ΔV is ΔV0, the region represented by the voltage fluctuation amount ΔΔV when the active ingredient Ir increases and the voltage fluctuation amount ΔΔV'when the invalid component Ii increases is displayed.

From this relationship in FIG. 10, α and β can be expressed by equations (4) and (5). These coefficients α and β are nothing but the determination of the SVR set values R2 and X2 associated with the season and time zone.
[Equation 4]
α = ΔΔV / ΔIr (4)
[Equation 5]
β = ΔΔV'/ ΔIi (5)
In the embodiment of FIG. 1, an example in which the automatic voltage regulator SVR and the distribution equipment design support system 400 are separately arranged to perform signal transmission is shown, but FIG. 11 shows an SVR set value determining means in the automatic voltage regulator SVR. An embodiment provided with 400A is shown. The SVR set value determining means 400A includes a database DB3A, a photovoltaic power generation device PVi output calculating means 440A, a photovoltaic power generation device output suppression estimation and ranking means 460A, and an SVR passing current and multiple regression analysis means 480A. The measuring means 200 acquires the SVR passing currents Ir and Ii, the automatic voltage regulator SVR and the potential difference ΔVi between the PVi output points of the photovoltaic power generation device, and the amount of solar radiation, and the PVi output amount calculating means 440A of the photovoltaic power generation device and the photovoltaic power generation device. After selecting data having a correlation with the output suppression of the photovoltaic power generation device by the output suppression estimation and ranking means 460A, the SVR set value 350 is tap-controlled 310 by the means of 480A that performs multiple regression analysis with the SVR passing current. Indicates to be set to.

The concept of processing described with reference to FIGS. 1 and 11 will be described with reference to FIGS. 12a and 12b. First, FIG. 12a shows an example of a surface area configuration of a distribution system extended and arranged in a dendritic shape from a substation 110 via an automatic voltage regulator SVR. In the power distribution system, the photovoltaic power generation device PV is arranged at the position of “◯”. Here, it is assumed that the position of the virtual point on the secondary side of the automatic voltage regulator SVR defined by the operation setting values R1 and X1 of the line voltage drop compensation circuit LDC1 which is an existing device is G1. The virtual point corresponds to the position of the center of gravity of the impedance distribution in the area configuration of the distribution system. Therefore, if this point is voltage-controlled, it is possible to properly voltage-control the entire distribution system.

On the other hand, FIG. 12b shows only the photovoltaic power generation device PV having a correlation with the output suppression in the photovoltaic power generation device PV, which is obtained by the photovoltaic power generation device output suppression estimation and ranking means 460 of FIGS. 1 and 11. It is shown by. In the multiple regression analysis means 480 with the SVR passing current, the output suppression is particularly large in consideration of the arrangement information of the photovoltaic power generation device PV having a correlation with the extracted output suppression, and the SVR secondary side voltage and the photovoltaic power generation device PVi For the photovoltaic power generation device PVi having a large correlation with the potential difference ΔVi with the terminal voltage, the position G2 of the center of gravity of the impedance distribution in the area configuration of the distribution system is obtained. The operation setting values R2 and X2 of the line voltage drop compensation circuit LDC2 of the present invention indicate the center of gravity position G2. According to the present invention, by setting a position closer to the photovoltaic power generation device to be output suppressed as a virtual point, tap control in the automatic voltage regulator SVR is distributed so that the voltage in the vicinity does not deviate from the limit value. Since the voltage of the system is adjusted, the photovoltaic power generation equipment, which has many opportunities to suppress the output, can be placed in a favorable environment without being suppressed.

In the conventional case, the output status of the photovoltaic power generation device PV is not considered only by controlling the center of gravity position G1 once determined, but in the present invention, the photovoltaic power generation device PV having a correlation in descending order of output suppression. Since only is extracted and reflected as the center of gravity position G2 each time, it is possible to avoid the unfairness of a specific photovoltaic power generation device PV that is suffering a loss of power sales opportunity due to output suppression.

As a result, even if the output of the photovoltaic power generation device PV rises excessively, the tap control in the automatic voltage regulator SVR on the upstream side adjusts the voltage of the distribution system in advance, so that the voltage of the photovoltaic power generation device PV is adjusted. It is possible to reduce the chances of output suppression.

By the above control according to the present invention, there is an effect that the output suppression amount of photovoltaic power generation can be reduced even in a system in which a large amount of photovoltaic power generation is introduced into a branch system or the like. In addition, by adjusting the voltage of the system only when the voltage adjustment device suppresses the output of photovoltaic power generation, it is possible to improve the voltage adjustment capacity of the voltage adjustment device at all times, and the load that can be connected to the distribution system Countermeasures against an increase in the amount of solar power generation This has the effect of reducing equipment costs.

It can be used as a voltage regulator that adjusts the voltage of the distribution system. It can also be used as a control system for an automatic voltage regulator SVR, which is a voltage regulator, and a distribution substation LRT. In addition, in the distribution system, it can be used as a voltage maintenance measure and a distribution facility capacity factor improvement measure corresponding to the expansion of distributed power sources such as solar power generation.

100: Distribution system 110: Distribution substation 120: Node PV: Solar power generation device 140: Distribution line 150: Load 170: Sensor 300: Automatic voltage regulator 302: Tap changer 303: Autotransformer 305: Transformer 310 : Tap control device CT: Current sensor PT: Voltage sensor 320: Control device measurement unit LDC1, LDC2: Line voltage drop compensation circuit 340: Tap control device DB1, DB2, DB3: Database

Claims (10)

Voltage adjustment of a distribution system equipped with a transformer with a tap that is installed in a distribution system equipped with multiple photovoltaic power generation devices with an output suppression function and adjusts the tap to set the voltage at the virtual point of the distribution system as the set voltage. It ’s a device,
The solar power generation device output amount calculation means for calculating the output amount of the photovoltaic power generation device and the output suppression amount of the photovoltaic power generation device by the output suppression function are obtained, and the solar power generation device is ranked according to the output suppression amount. The position of the center of gravity of the distribution system including the ranked photovoltaic power generation device is determined as a virtual point by the multiple regression analysis of the passing current of the tapped transformer and the output suppression amount estimation and ranking means of the photovoltaic power generation device. An analysis means for determining a set value representing the distance from the tapped transformer to the virtual point, a line voltage drop compensation circuit for estimating the voltage at the virtual point using the set value, and a voltage at the virtual point. A voltage regulator for a distribution system, characterized by having a tap control device that controls to a set voltage. The voltage adjusting device for the distribution system according to claim 1.
The voltage regulator obtains information from the measuring means for the passing current of the tapped transformer, the potential difference between the tapped transformer and the installation point of the solar power generation device, and the amount of solar radiation, and obtains information from the measuring means. It is provided with storage means including information, information on the configuration of the target distribution system, information on the arrangement / capacity of the solar power generation device, information on the load pattern, and information on the arrangement data of the tapped transformer. A voltage regulator for a distribution system, which is characterized by this. The voltage adjusting device for the distribution system according to claim 1 or 2.
A voltage regulator for a distribution system, wherein a set value representing a distance from the tapped transformer to the virtual point is an impedance during this period or a coefficient related to the impedance. The voltage adjusting device for a power distribution system according to any one of claims 1 to 3.
The line voltage drop compensating circuit includes at least two sets, and the first line voltage drop compensating circuit adjusts the tap of the tap control device so that the voltage at the first virtual point in the distribution system is set as the set voltage. The line voltage drop compensation circuit of No. 2 is characterized in that the tap of the tap control device is adjusted so that the voltage at the second virtual point in the distribution system is set as the set voltage by using the set value obtained by the analysis means. The voltage regulator of the distribution system. A voltage adjustment system for a distribution system equipped with a transformer with a tap that adjusts the tap so that the voltage at the virtual point of the distribution system is the set voltage, and multiple photovoltaic power generation devices with output suppression functions.
For a plurality of photovoltaic power generation devices, the output suppression amount is estimated based on the output amount calculation means for calculating the output amount and the output amount obtained for each photovoltaic power generation device, and arranged according to the output suppression amount. By multiple regression analysis of the passing current of the tapped transformer and the ranking means for performing the replacement, the position of the center of gravity of the distribution system including the rearranged photovoltaic power generation device is determined as a virtual point, and the tapped transformer is described as described above. A power distribution facility design support system equipped with an analysis means for determining a set value that represents the distance to a virtual point, and
An automatic voltage including a line voltage drop compensation circuit that estimates the voltage at the virtual point and a tap control device that controls the voltage at the virtual point to a set voltage using the set value determined by the distribution equipment design support system. Adjustment device and
Distribution system voltage regulation system including. The voltage adjusting system for the distribution system according to claim 5.
The power distribution equipment design support system obtains information from measuring means for the passing current of the tapped transformer, the potential difference between the tapped transformer and the installation point of the solar power generation device, and the amount of solar radiation, and measures the measurement. A storage means including information from the means, information on the configuration of the target distribution system, information on the arrangement / capacity of the solar power generation device, information on the load pattern, and information on the arrangement data of the tapped transformer. A voltage adjustment system for the distribution system, which is characterized by being equipped. Voltage adjustment of a distribution system equipped with a transformer with a tap that is installed in a distribution system equipped with multiple photovoltaic power generation devices with an output suppression function and adjusts the tap to set the voltage at the virtual point of the distribution system as the set voltage. The way,
For a plurality of photovoltaic power generation devices, the output amount is estimated, the photovoltaic power generation devices are extracted in descending order of the output suppression amount obtained for each photovoltaic power generation device, and the distribution system including the extracted photovoltaic power generation device A method for adjusting a voltage of a distribution system, characterized in that the position of the output center of gravity of the photovoltaic power generation device is determined as a virtual point and the voltage at the virtual point is controlled to a set voltage. Voltage adjustment of a distribution system equipped with a transformer with a tap that is installed in a distribution system equipped with multiple photovoltaic power generation devices with an output suppression function and adjusts the tap to set the voltage at the virtual point of the distribution system as the set voltage. The way,
For a plurality of photovoltaic power generation devices, the output amount suppression amount by the output suppression function is estimated, and for the photovoltaic power generation device that suppresses the output, the output center of gravity position of the photovoltaic power generation device is determined as a virtual point, and the voltage at the virtual point is set. A voltage adjustment method for a distribution system, which comprises controlling the voltage to a set voltage. It is installed in a distribution system equipped with multiple photovoltaic power generation devices with output suppression function, and is applied to a distribution system equipped with a tapped transformer that adjusts the tap to set the voltage at the virtual point of the distribution system as the set voltage. , A distribution facility design support system for a distribution system that gives a set value for estimating the voltage at the virtual point.
The solar power generation device output amount calculation means for calculating the output amount of the photovoltaic power generation device and the output suppression amount of the photovoltaic power generation device by the output suppression function are obtained, and the solar power generation device is ranked according to the output suppression amount. The position of the center of gravity of the distribution system including the ranked photovoltaic power generation device is determined as a virtual point by the multiple regression analysis of the passing current of the tapped transformer and the output suppression amount estimation and ranking means of the photovoltaic power generation device. A power distribution system is provided with an analysis means for determining a set value representing a distance from a tapped transformer to the virtual point, and an output means for giving the set value obtained by the analysis means to the tapped transformer. Equipment design support system. The distribution facility design support system for the distribution system according to claim 9.
Information is obtained from the measuring means for the passing current of the tapped transformer, the potential difference between the tapped transformer and the installation point of the photovoltaic power generation device, and the amount of solar radiation, and the information from the measuring means and the target. It is characterized by having a storage means including information on the configuration of the distribution system to be used, information on the arrangement / capacity of the photovoltaic power generation device, information on the load pattern, and information on the arrangement data of the tapped transformer. Distribution equipment design support system for distribution systems.

Images