JP5394351B2 - Voltage suppression processing apparatus and voltage suppression processing method - Google Patents

Description

  The present invention relates to an apparatus and a method for suppressing a voltage when a voltage of a distribution line is increased by a solar power generation device.

  In recent years, as a part of global warming countermeasures, an increasing number of people are installing solar power generation devices at home so as to respond to the purchase system of power generated by natural energy. In many cases, the amount of power generated by a solar power generation device changes depending on the weather, and the voltage of the distribution line is increased during power generation. On the other hand, when the AC side voltage of the inverter of the solar power generator rises to a specified value, the solar power generator itself suppresses power generation, and a state where power generation is not possible occurs despite having power generation capability. Sometimes.

Therefore, the following techniques have been proposed as a solution for these problems.
(1) Patent Document 1 “Photovoltaic power generation apparatus and control method thereof”
When the AC voltage of the inverter part of the photovoltaic power generator exceeds the specified value, the inverter part and the load (a power storage device including a rechargeable battery such as an electric water heater or a secondary battery such as a lead storage battery or a fuel cell) The on / off load and the electric capacity are controlled by an energization controller provided between the two.
(2) Patent Document 2 “Hot-storage water heater and program”
Depending on the weather forecast information, if the amount of hot water in the hot water storage tank is less than or equal to the amount of hot water used by the user during the day, the hot water is boiled up to that constant amount of water at midnight, and the power generated by the photovoltaic power generator is Use it to boil the remaining hot water. Also, if there is more than a certain amount of hot water in the hot water storage tank, the hot water is not boiled at midnight, but the remaining hot water is boiled using solar power during the day. This will reduce the use of late-night power without sacrificing user convenience and aim to save energy.

Japanese Patent No. 3942400 JP 2008-2703 A

However, the following problems remain in the above prior art.
(1) Patent Document 1 “Photovoltaic power generation apparatus and control method thereof”
When the AC side voltage of the inverter unit of the photovoltaic power generator rises to the specified value, we think that it is possible to suppress the voltage rise of the distribution line by passing the photovoltaic power to the load in the home, It is not a technology to continue selling electricity by photovoltaic power generation.
(2) Patent Document 2 “Hot-storage water heater and program”
Although it is considered possible to suppress the voltage rise of the distribution line by utilizing solar power generated in the electric water heater in the house, it is not a technology to continue selling power by solar power generation.

  The present invention has been made in view of the above problems, and a main purpose thereof is to suppress a voltage increase of a distribution line by a distributed power source and to continue selling electric power generated by the distributed power source.

In order to solve the above-mentioned problem, the present invention is a voltage suppression processing device, which stores an allowable voltage upper limit value that is an upper limit value of a voltage allowable range in a distribution line, and is installed at each point of the distribution line. Means for obtaining a voltage value measured at each point from the voltmeter, means for obtaining a countermeasure time which is a time required for voltage suppression measures for the distribution line, and at least one of the obtained voltage values Is greater than the allowable voltage upper limit value, the voltage drop is calculated by subtracting the allowable voltage upper limit value from the voltage value greater than the allowable voltage upper limit value, and the distribution line should be linked to the voltage drop. Select an electric water heater, and calculate the amount of hot water required to bring the voltage value at the relevant point of the distribution line into an allowable range based on the total power consumption of the electric water heater and the acquired countermeasure time Means for obtaining a residual water amount that is the amount of water remaining in each tank of the electric water heater, and means for allocating the amount of hot water to each electric water heater based on the obtained residual water amount And means for instructing each electric water heater to which the amount of water of the hot water is distributed to instruct the hot water .

According to this configuration, it is possible to suppress an increase in the distribution line voltage by boiling the electric water heater connected to the distribution line and increasing the current flowing from the distribution line to the load. And by using an electric water heater as a load, the amount of power consumed by boiling water can be adjusted according to the amount of water remaining in the tank, and a voltage drop that lasts for the necessary countermeasure time can be obtained. . In addition, for example, even when the distribution line voltage rises due to power from a distributed power source such as photovoltaic power generation installed at a certain customer's house, the electric water heater at the other consumer's house consumes the increased amount of power. In addition, since the distribution line voltage is suppressed, electric power from the distributed power source can be supplied to the outside of the house and the power sale can be continued.
In addition, the amount of water currently remaining in each tank is obtained, and the necessary amount of water is boiled with an electric water heater based on that amount, thereby boiling the amount of water necessary for suppressing distribution line voltage. As a result, the voltage can be suppressed with high accuracy.

Further, in the voltage suppression processing apparatus of the present invention, the means for allocating the amount of boiling water to each electric water heater is a distributed power source connected to the distribution line or a substation that transmits system power to the distribution line. A nearby electric water heater may be preferentially selected.
According to this configuration, when the water heater is heated in the vicinity of the distributed power source, the distribution line voltage raised by the generated power of the distributed power source can be immediately lowered on the spot. In addition, if the water heater is used in the vicinity of the substation, the distribution line voltage is suppressed in the vicinity of the transmission source of the system power, and the voltage of the entire distribution line from the vicinity of the transmission source to the terminal can be lowered. According to this, the electric water heater in the location effective for voltage suppression is selected, and the process of a voltage suppression countermeasure can be efficiently performed by instruct | indicating boiling.

Further, in the voltage suppression processing apparatus of the present invention, based on the next day's weather information, power demand and distribution line status, the time when the distribution line voltage value becomes larger than the allowable voltage upper limit value by the distributed power source the next day. Calculate the amount of water required for the next day based on the predicted result, the means for predicting the belt, point and voltage value, select the electric water heater that should be heated on the next day, and select the electric water heater for each selected electric water heater. The apparatus may further include means for allocating the amount of water for the kettle, and means for instructing each electric water heater to which the amount of water for the kettle is allocated to secure water.
According to this configuration, it is possible to quickly cope with the increase in the distribution line voltage of the day by securing the amount of water that will be necessary for the suppression of the distribution line voltage of the next day (the same day) on the previous day.

  The present invention includes a voltage suppression processing method. In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the description of the mode for carrying out the invention and the drawings.

  ADVANTAGE OF THE INVENTION According to this invention, while suppressing the voltage rise of the distribution line by a distributed power supply, the sale of the electric power generated by a distributed power supply can be continued.

It is a figure which shows the structure of the power distribution system. It is a figure which shows the functional block structure of the voltage suppression processing apparatus 7, and its peripheral apparatus structure. It is a figure which shows the structure of the data memorize | stored in the memory | storage part 75 of the voltage suppression processing apparatus 7, (a) shows the structure of the electric power demand database 75A, (b) shows the structure of the distribution line system database 75B, c) shows the configuration of the distribution line work plan database 75C. 3 is a flowchart showing processing of a voltage suppression processing device 7; It is a figure which shows the structural example of the power distribution system. It is a figure which shows the voltage of the high voltage distribution line 3 before and behind a power suppression measure, (a) shows the distribution line voltage before a countermeasure, (b) shows the distribution line voltage after a countermeasure. It is a figure which shows the example of a schedule of a voltage suppression measure. It is a figure which shows the Example of the electric water heater 61, (a) shows Example 1 of an electric water heater, (b) shows Example 2 of an electric water heater. It is a figure which shows the Example of the ecocute 62. FIG. It is a figure which shows the Example of the watt-hour meter with a communication function.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The power distribution system according to the embodiment of the present invention connects an electric water heater to the distribution line as a load when the voltage of the distribution line connected to a distributed power source such as a photovoltaic power generator rises. , Excess power is consumed. At that time, based on the distribution line system and the state of power demand, an electric water heater at a point where voltage suppression is effective is preferentially selected as a connection target. According to this, while suppressing the voltage rise of the distribution line by a distributed power supply, even if a voltage rise generate | occur | produces, the electric power generation and power sale by a distributed power supply can be continued.

≪System configuration and overview≫
FIG. 1 is a diagram illustrating a configuration of a power distribution system 1. The power distribution system 1 is a system related to a power distribution system including a distribution line that transmits power to the substation, a load connected to the distribution line, and a distributed power source. The substation 2, the high-voltage distribution line 3, and the measuring device 4 , Pole transformer TR, low voltage line 5, customer home 6, solar power generation device PV, voltage suppression processing device 7, network 8 and weather information server 9. The substation 2 receives power from a power plant or another substation (not shown) and transmits a high voltage (for example, 6600 V) to the high-voltage distribution line 3. The high-voltage distribution line 3 is connected to the substation 2 and is extended by a steel tower or the like to distribute the high voltage received from the substation 2 to each region. The measuring device 4 is installed in a steel tower or the like, measures voltage, current, power, etc. at each point of the high-voltage distribution line 3 and transmits the measurement data to the voltage suppression processing device 7.

  The pole transformer TR has the high voltage distribution line 3 connected to the high voltage side and the low voltage line 5 connected to the low voltage side, and transforms, for example, a high voltage of 6600V and a low voltage of 100V to each other. The low-voltage line 5 is a low-voltage distribution line and a lead-in line that connects the low-voltage side of the pole transformer TR and the customer's house 6, and supplies power from the pole transformer TR to the load of the customer's house 6, while the customer Electric power is transmitted from the distributed power source of the house 6 to the pole transformer TR. The customer home 6 is a customer's home that has a power use or power sale contract with an electric power company, such as a load of household electrical appliances that consume system power, a solar power generation device PV that generates power, etc. Distributed power supply is installed. In addition, in the customer's house 6, there is a house provided with an electric water heater such as an electric water heater 61 and an ecocute 62 (see FIG. 2, “Ecocute” is a registered trademark) as one of loads.

  The voltage suppression processing device 7 is a device that turns on the electric water heater in the customer's house 6 when the voltage of the high-voltage distribution line 3 rises, and performs processing so that power is consumed. While connecting to the electric water heater provided in the house 6, it connects to the weather information server 9 via the network 8 such as the Internet. The weather information server 9 transmits future weather prediction information to the voltage suppression processing device 7.

  FIG. 2 is a diagram showing the functional block configuration of the voltage suppression processing device 7 and the peripheral device configuration. The voltage suppression processing device 7 is connected to the measurement device 4, the network 8, the electric water heater 61, and the ecocute 62 so that they can communicate with each other.

  The voltage suppression processing device 7 includes a communication unit 71, a display unit 72, an input unit 73, a processing unit 74, and a storage unit 75, and is configured so that each unit can transmit and receive data via a bus (not shown). . As a communication unit 71 that transmits and receives data to and from an external device, a measurement data receiving unit 71A, a weather forecast information receiving unit 71B, an electric water heater transmitting unit 71C, and an electric water heater receiving unit 71D are provided. The measurement data receiving unit 71A receives measurement data such as the current, voltage, and power of the high-voltage distribution line 3 from the measurement device 4 and outputs the measurement data to the voltage suppression measure amount calculation unit 74A, and the power demand database 75A via the processing unit 74. To remember. The weather prediction information receiving unit 71B receives the weather prediction information via the network 8, and outputs the weather prediction information to the voltage suppression measure amount calculation unit 74A and the voltage rise prediction point calculation unit 74D. The electric water heater transmission unit 71C acquires command data from the countermeasure command unit 74C and the reserved water amount distribution calculation unit 74F, and transmits the command data to the electric water heater 61 and the eco-cute 62. The electric water heater receiving unit 71D receives the remaining water amount data, the measured value of the water temperature, and the set value of the hot water temperature from the electric water heater 61 and the eco-cute 62, and outputs them to the measureable customer selecting unit 74B.

  The display unit 72 is a part that displays data according to an instruction from the processing unit 74, and is realized by, for example, a liquid crystal display (LCD). The input unit 73 is a part where an operator inputs data (for example, work schedule data related to the high-voltage distribution line 3), and is realized by, for example, a keyboard or a mouse.

  A CPU (Central Processing Unit) executes a program on the memory, and as a module of the processing unit 74 that controls the entire voltage suppression processing device 7, a voltage suppression countermeasure amount calculation unit 74A, a countermeasure-capable customer selection unit 74B, a countermeasure command A unit 74C, a voltage rise prediction point calculation unit 74D, a pre-reserved water amount calculation unit 74E, and a reserved water amount distribution calculation unit 74F are provided.

  When the voltage at a certain point of the high voltage distribution line 3 obtained from the measurement data receiving unit 71A on the day exceeds the reference value, the voltage suppression measure amount calculation unit 74A suppresses the voltage to be within the reference value. Therefore, the necessary countermeasure amount (voltage for each switch section) is calculated and output to the countermeasure-capable customer selection unit 74B.

  The countermeasure-capable customer selection unit 74B obtains the countermeasure amount necessary for voltage suppression from the voltage suppression countermeasure amount calculation unit 74A, calculates the amount of water necessary to realize the countermeasure amount by boiling, and the electric water heater The remaining water amount of each electric water heater is acquired from the receiver 71D, and the customer home 6 capable of implementing voltage suppression measures is selected based on the amount of water required for boiling and the actual remaining water amount. For example, if the countermeasures are not sufficient with only the electric water heaters of the customer group 6 of the group A, which is a group under the same pole transformer TR, the scope of the countermeasures to be implemented in the customer group 6 of another group spread. Another group is close to the group A, and basically a place where many photovoltaic power generation devices PV are installed is selected, but when the photovoltaic power generation devices PV are dispersed, for example, Also near the substation 2 is a candidate for selection. At that time, the distribution line system database 75B is referred to.

  In addition, the measureable customer selecting unit 74B acquires the measured value of the water temperature and the set value of the hot water temperature in each electric water heater from the electric water heater receiving unit 71D, and “set value of the hot water temperature <water temperature in the tank + 20 ° C.” If it is, the change command is transmitted to the electric water heater so that the set value of the hot water temperature is “water temperature in the tank + 20 ° C.”. 20 degreeC is a part for the temperature rise at the time of making water into hot water.

  The countermeasure command unit 74C obtains the customer home 6 that can be countermeasured from the countermeasure-capable customer selection unit 74B, the distribution of the amount of water, and the set value of the hot water that needs to be changed (change command to the electric water heater). A countermeasure command is issued to the electric water heater 61 and the ecocute 62 via the heater transmitter 71C.

  On the high-voltage distribution line 3, the voltage rise prediction point calculation unit 74 </ b> D is predicted that the voltage will rise above the reference value on the next day based on the next day's weather information and each database acquired from the weather prediction information receiving unit 71 </ b> B. And the amount of measures necessary to suppress the increased voltage within the reference value are calculated and output to the pre-reserved water amount calculation unit 74E. The pre-reserved water amount calculation unit 74E obtains a countermeasure amount necessary for voltage suppression on the next day from the voltage rise prediction point calculation unit 74D, and calculates the amount of water to be secured in advance when the countermeasure amount is realized by boiling water. . The reserved water amount distribution calculating unit 74F acquires the amount of water to be secured from the pre-reserved water amount calculating unit 74E, calculates the distribution of the amount of water to be secured for each electric water heater, and via the electric water heater transmitting unit 71C. Thus, a securing command is issued to the electric water heater 61 and the ecocute 62.

  The storage unit 75 that stores data from the processing unit 74 and reads the stored data includes a power demand database 75A, a distribution line system database 75B, and a distribution line work plan database 75C. Details thereof will be described separately.

  The electric water heater 61 and the eco cute 62 are electric water heaters provided in each customer home 6 and may not be the customer home 6 in which the solar power generation device PV is installed. The mainstream of the electric water heater 61 is to boil all the remaining water at midnight. The EcoCute 62 has a tank with a capacity of several hundred liters, and can boil water in units of 1 liter at night or during the day. Therefore, for example, by first boiling all the water in the electric water heater 61 and then adjusting to the liter unit with the ecocute 62, it is possible to consume power with high accuracy, and thus to suppress the voltage of the high-voltage distribution line 3 with high accuracy. Can do.

  As shown in FIG. 2, the electric water heater 61 includes a communication unit 61A, a watt-hour meter 61B, a residual water amount measurement unit 61C, a water temperature measurement unit 61D, and a hot water temperature setting unit 61E. The communication unit 61 </ b> A is a part that transmits and receives data to and from the voltage suppression processing device 7. The watt-hour meter 61B measures the amount of power consumed by the electric water heater 61 and receives a command from the voltage suppression processing device 7 to ensure the remaining water amount, start and end of boiling water, and set hot water temperature. Control retention. The remaining water amount measuring unit 61 </ b> C measures the amount of water remaining in the tank of the electric water heater 61 and notifies the voltage suppression processing device 7. The water temperature measurement unit 61 </ b> D measures the water temperature in the tank and notifies the voltage suppression processing device 7. The hot water temperature setting unit 61E stores the hot water temperature setting value, changes it according to a command from the voltage suppression processing device 7, and notifies the voltage suppression processing device 7 of the current hot water temperature setting value.

  The eco-cute 62 includes a communication unit 62A, a watt-hour meter 62B, a remaining water amount measurement unit 62C, a device state recognition unit 62D, a water temperature measurement unit 62E, and a hot water temperature setting unit 62F. The communication unit 62 </ b> A is a part that transmits and receives data to and from the voltage suppression processing device 7. The watt-hour meter 62B measures the amount of power consumed by the Ecocute 62 and receives instructions from the voltage suppression processing device 7 to secure the remaining water amount, start and end of boiling water, and maintain the set hot water temperature. Control. The remaining water amount measuring unit 62 </ b> C measures the amount of water remaining in the tank of the ecocute 62 and notifies the voltage suppression processing device 7. The device state recognition unit 62D recognizes the operating / stopped state of the ecocute 62 and notifies the voltage suppression processing device 7 of it. The water temperature measurement unit 62E measures the water temperature in the tank and notifies the voltage suppression processing device 7 of the water temperature. The hot water temperature setting unit 62F stores the hot water temperature setting value, changes it in accordance with a command from the voltage suppression processing device 7, and notifies the voltage suppression processing device 7 of the current hot water temperature setting value.

<< Data structure >>
FIG. 3 is a diagram illustrating a configuration of data stored in the storage unit 75 of the voltage suppression processing device 7. FIG. 3A shows the configuration of the power demand database 75A. The power demand database 75A is a database related to power demand in the high-voltage distribution line 3, and stores measurement data 75A1 and countermeasure time 75A2. The measurement data 75A1 is measurement value data such as voltage, current, and power received from each measurement device 4. The countermeasure time 75A2 indicates the time required for the voltage suppression countermeasure for the high-voltage distribution line 3, and is set to, for example, 2 hours. Depending on whether each tank is heated sequentially or in parallel, the time for the entire water heating based on the amount of water in each tank also changes. Therefore, if the countermeasure time 75A2 is determined, the water heating schedule needs to be adjusted. If determined, the countermeasure time 75A2 can be calculated.

  FIG. 3B shows the configuration of the distribution line system database 75B. The distribution line system database 75B is a database relating to the high-voltage distribution line 3 and its subordinates, and stores the low-voltage allowable range 75B1, distribution line impedance 75B2, transformer transformation ratio 75B3, customer home data 75B4, and active distribution line path 75B5. The low voltage allowable range 75B1 indicates a voltage allowable range on the low voltage side of the pole transformer TR, and for example, a range of 101 ± 6V or 101 ± 3V is set. Distribution line impedance 75B2 shows the impedance between each point on the high voltage distribution line 3, and the impedance from the substation 2 to each point can be calculated by these. The transformer transformation ratio 75B3 is a transformation ratio (for example, 6600V / 100V) of each pole transformer TR. Customer home data 75B4 includes the presence / absence of an electric water heater (electric water heater 61 and Ecocute 62) at each customer home 6, the capacity of the electric water heater when present, the presence / absence of the solar power generation device PV, and the power generation capacity when present. Remember. The customer home data 75B4 is classified for each connection position on the high voltage distribution line 3 (interconnection point of the pole transformer TR). The operating distribution line route 75B5 indicates the route of the distribution line that is actually operating at the present time, and the latest state is updated and set as needed. For example, when there is a high-voltage distribution line 3A and 3B and an accident occurs in the high-voltage distribution line 3A normally used by the customer's home 6C, the high-voltage distribution line 3B is used. At this time, the route of the distribution line in operation is changed, and the distribution route from the substation 2 to the customer's house 6C changes, so the voltage drop changes. Therefore, it is necessary to always grasp the latest distribution line route.

  FIG.3 (c) shows the structure of the distribution line work plan database 75C. The distribution line work plan database 75C is a database related to a work plan for the high-voltage distribution line 3, and stores the work schedule 75C1 and the change contents 75C2 on the day. The work schedule 75C1 indicates a work schedule for each switch section of the high-voltage distribution line 3. As for the change contents 75C2 on the day, the contents of the work schedule 75C1 that are changed on the current day are quickly updated.

≪System processing≫
FIG. 4 is a flowchart showing processing of the voltage suppression processing device 7. In the voltage suppression processing device 7, this processing is performed mainly by the processing unit 74 transmitting and receiving data to and from other devices via the communication unit 71, while referring to and updating data in the storage unit 75. Voltage suppression is performed.

  First, on the day before the processing target day, the voltage suppression processing device 7 predicts at what point on the high-voltage distribution line 3 the voltage increase will occur at what time on the next day (that is, the day of the processing target day) ( S401). Specifically, the power demand database 75A (the previous day and past measurement data 75A1), the distribution line system database 75B (the upper limit value of the low voltage allowable range 75B1, the state of the high voltage distribution line 3 in the operating distribution line route 75B5, the customer home data 75B4 Based on weather forecast information from the distribution line work plan database 75C (work schedule for the next day 75C1) and the weather information server 9, the time zone during which the distribution line voltage rises the next day will occur. And predict points. At this time, a power flow and voltage calculation method based on Ohm's law is used. For example, when the power demand is reduced while the amount of solar radiation is increased, the surplus power is increased and the voltage value of the high-voltage distribution line 3 is estimated to exceed the upper limit value. Estimate the value.

  Next, the voltage suppression processing device 7 calculates how much water should be secured in the electric water heater at which point based on the predicted point on the high-voltage distribution line 3, and each electric water heater A distribution securing command is output to 61 and ecocute 62 (S402). That is, the amount of water to be boiled in the time zone of the next day, in which the voltage of the high-voltage distribution line 3 will be increased by the photovoltaic power generation device PV, for example, in advance in an electric water heater located around the predicted point of voltage increase To ensure. At that time, a contract plan and a charge menu are created for the customer's home 6 who has agreed to cooperate in voltage suppression measures for the high-voltage distribution line 3, and water is requested in advance.

  For example, with a customer's house 6 that has a 400L tank but uses only 300L of hot water every day, a contract is made to always leave 100L of water in the tank, and instead discount the electricity bill. do. And when such a contract is 100 customer homes 6 and it is predicted that the amount of water of 8000 L is required on the previous day, 80 customer homes 6 are scheduled to boil 100 L in advance and secure water. We contacted us to request a new request, and in case we could run out of the required amount of water, we would like to request that 20 customers' homes 6 boil water and request 100L of water. To do.

  On that day, the voltage suppression processing device 7 acquires a voltage value from the measuring device 4 installed at each point of the high-voltage distribution line 3 and monitors whether or not a voltage increase has occurred in the high-voltage distribution line 3 ( S403). For example, whether or not at least one voltage value obtained by converting each measured voltage on the high voltage side of the pole transformer TR to the low voltage side by the transformer transformation ratio 75B3 exceeds 107V (the upper limit value of the low voltage allowable range 75B1). Check. If no voltage increase has occurred (NO in S403), monitoring of the voltage value acquired from each measuring device 4 is continued (S403). If the voltage rise has occurred (YES in S403), the power demand database 75A (measure time 75A2), the distribution line system database 75B (distribution line impedance 75B2, active distribution line route 75B5), distribution line work plan database 75C (on the day) Based on the change contents 75C2) and the voltage and current measurement data in the high-voltage distribution line 3, a countermeasure amount (voltage value) necessary for suppressing the voltage rise is calculated (S404). At this time, the measure amount is calculated for each switch section using a technique such as tidal current calculation.

  Next, in order to confirm whether there is an amount of water to be boiled according to the countermeasure amount of voltage suppression, the voltage suppression processing device 7 from the electric water heater 61 and the ecocute 62 that issued the allocation securing command the previous day. The amount of water currently remaining in the tank, the measured value of the water temperature, and the set value of the hot water temperature are acquired (S405). Then, based on the distribution line system database 75B (customer home data 75B4), an electric water heater at a point (for example, the customer home 6 where the solar power generation device PV is installed or the vicinity thereof) effective in suppressing the voltage rise. (Electric water heater 61 and Ecocute 62) are selected (S406). Then, based on the selection result, power on / off of the target electric water heater is controlled (S407). By connecting the electric water heater to the high voltage distribution line 3 as a load, the current flowing from the high voltage distribution line 3 to the load can be increased, and the voltage increase of the high voltage distribution line 3 can be suppressed.

  For example, the amount of water remaining at 14:00 on the day is received in a lump, and 80 people who contacted the use of water the day before give instructions to boil hot water. Give instructions to boil 20 houses that contacted the day before to secure water. At that time, for example, by issuing an instruction to boil the water in the order of increasing amount of remaining water in 20 houses, it is possible to efficiently perform voltage suppression processing.

  Thereafter, in order to confirm the effect of the voltage suppression measure and detect the occurrence of a new voltage increase, the process returns to the voltage increase check in S403.

  In addition, regarding the measured value of the water temperature in the tank of the electric water heater and the set value of the hot water obtained in S405, if the difference between them is smaller than 20 ° C, the set value of the hot water temperature so that the difference becomes 20 ° C. A command to change the power is issued to the electric water heater.

<Example>
FIG. 5 is a diagram illustrating a configuration example of the power distribution system 1. On the high-voltage distribution line 3, points A, B, C, D, and E are provided as connection points for each pole transformer TR, and the customer home 6 under each pole transformer TR The groups are designated as A group, B group, C group, D group and E group, respectively. An SVC (Static Var Compensator) is provided upstream of the point B. The SVC is also called a static reactive power compensator, and performs reactive power compensation with a fast response speed by continuously changing reactive power in a load state. Here, it plays a role of increasing the voltage in the middle of the high-voltage distribution line 3. In addition, the impedance of each distribution line is shown below.
・ Substation 2 to point A: 132Ω
-Point A to SVC: 66Ω
· SVC ~ B point: 66Ω
・ Points B to C: 132Ω
-C point to D point: 132Ω
-D point to E point: 132Ω

  FIG. 6 is a diagram illustrating the voltage of the high-voltage distribution line 3 before and after the power suppression measure. Fig.6 (a) shows the distribution line voltage before a countermeasure. FIG.6 (b) shows the distribution line voltage after a countermeasure.

  Hereinafter, an example of the processing of the voltage suppression processing device 7 performed on the day will be described with reference to FIGS. 5 and 6.

(S1) From the voltage measurement value of the measuring device 4 installed in the high voltage distribution line 3, it is estimated that the voltage value at point A is 6820V. This is because if there is nothing in the middle of the distribution line, the voltage drops or rises uniformly (with a constant slope). That is, in the graph of FIG. 6A, when a straight line connecting the sending voltage 6700V at the substation 2 and the measurement voltage X of the measuring device 4 is extended to the downstream side, the extension line and the vertical passing through the point A The voltage value (high voltage side: 6820V) indicated by the point where the line intersects is specified. And the low voltage | pressure side of pole transformer TR is estimated to be 107.2V (= 6820 * 100/6360) by transformer transformation ratio 75B3.

(S2) Therefore, the low pressure side of the point A is adjusted to 105V (the upper limit value of the low pressure allowable range 75B1). That is, the high voltage side of the pole transformer TR is adjusted to about 6680V (≈6678 = 105 × 6360/100) by the transformer transformation ratio 75B3. As a result, the amount of countermeasures necessary for the voltage drop at point A is 140 V (= 6820-6680). That is, a load that generates a voltage drop of about 140V is required. Note that the voltage is adjusted so that it normally falls within the range of 101 ± 6V, but the current target is described to be about 101 ± 3V.

(S3) Electric power demand database 75A (measure time 75A2), distribution line system database 75B (electric water heater capacity of customer home data 75B4, operating distribution line route 75B5), distribution line work plan database 75C (change contents 75C2 on the day) Based on the above, the amount of water required for the measure is calculated.

An example of the calculation procedure is shown below.
(1) First, the time (countermeasure time) that requires voltage suppression is acquired from the power demand database 75A. Here, the countermeasure time is 2H.
(2) Acquire the power consumption of the electric water heater and the amount of water in the tank of the customer who has agreed to cooperate in voltage suppression measures.
(3) A voltage simulation based on the power consumption is performed, and a pattern for connecting the A to D group electric water heaters satisfying a necessary voltage drop to the system is derived.
(4) The amount of water required for the countermeasure is calculated from the total power consumption based on the derived pattern and the countermeasure time.
Water volume = Total power consumption x Countermeasure time x 860 kcal / 20 ° C

Assuming that the total power consumption is 14 KW, the required amount of water is about 1200 L (≈1204 L). In boiling water, the temperature is increased by 20 ° C. This is because the water temperature is around 20 ° C., and the average temperature of the hot water used is 40 ° C., so that the temperature rise of 20 ° C., which is the difference, is necessary to turn the water into hot water. is there.

(S4) The amount of water remaining in the electric water heater at the customer's house 6 that has accepted the cooperation for voltage suppression measures is acquired and summed for each group. (Group A: 800L, Group B: 400L, Group C: 400L, Group D: 700L)
(S5) The voltage simulation is started with the sending voltage of the substation 2 set to 6700V. The sending voltage of the substation 2 changes for each time zone, but is 6700 V in this time zone. Each impedance is calculated by the distribution line impedance 75B2. The voltage drop is obtained by multiplying the impedance at substations 2 to A by the current conversion value of the power consumption of each group.

[Example]
A voltage drop E (high voltage side) of 103.9 V is generated at the point A from the impedance 132Ω of the substations 2 to A and the power consumption of the group A 9.3 kW.
E = R × I = 132 × 9300 / (√3 × 6820) ≈103.9 [V]
A voltage drop E (high voltage side) of 23.1 V is generated at the point A from the impedance 132Ω of the substations 2 to A and the power consumption 2KW of the group B.
E = R × I = 132 × 2000 / (√3 × 6600) ≈23.1 [V]
A voltage drop E (high voltage side) of 23.2 V occurs at the point A from the impedance 132Ω at the substations 2 to A and the power consumption 2KW of the group C.
E = R × I = 132 × 2000 / (√3 × 6580) ≈23.2 [V]

From the above, a total voltage drop of 150.2 V can be expected at point A. In addition, it is confirmed that the amount of water commensurate with the amount of power for the countermeasure time of 2H is secured for each group. For example, regarding group A, it is shown below.
Necessary amount of water = Total power consumption x Countermeasure time x 860 kcal / 20 ° C
= 9.3KW × 2H × 860kcal / 20 ° C.
= 799.8 ≦ 800L
Next, it shows below about B group.
Necessary amount of water = Total power consumption x Countermeasure time x 860 kcal / 20 ° C
= 2KW × 2H × 860kcal ÷ 20 ° C
= 172 ≦ 400L
Next, it shows below about C group.
Necessary amount of water = Total power consumption x Countermeasure time x 860 kcal / 20 ° C
= 2KW × 2H × 860kcal ÷ 20 ° C
= 172 ≦ 400L

(S6) Power-on control is performed on the target water heaters in groups A, B, and C to boil the hot water.
(S7) After 2 hours, while (S1) to (S6) are repeated, the sun goes down and the voltage rise does not occur.
(S8) For the next day, based on the power demand database 75A (measurement data 75A1 on the day) and the distribution line work plan database 75C (work schedule 75C1 on the next day), the amount of water to be secured in advance is calculated, The distribution data is transmitted to 6.
For example, if the weather and the distribution line system are the same as on the day, data is transmitted so as to secure 800 L for the A group and 200 L for the B group and C group. The remaining 200 L of the B group and the C group are reserved and secured in the sense of “maybe used.” At this time, today's customer premises 6 that use 200L each are used for preliminary allocation, thereby maintaining the fairness of customers in the same group.
(S9) The next day is reached, and processing is performed from (S1).

In addition, distribution of the water with respect to the electric water heater in the same group is performed as follows, for example.
-The customer's house A1 of the A group is prepared in advance with 200 L of water with a 4 KW heater.
-The customer's home A2 of the A group is prepared in advance with 200 L of water with a 5.3 KW heater.
-The customer's home A3 of the A group is prepared in advance with 200 L of water with a 4 KW heater.
-The customer's home A4 of the A group is prepared in advance with 200 L of water with a 5.3 KW heater.

  Then, countermeasures are implemented according to the schedule shown in FIG. That is, of the two hours of countermeasure time, the electric water heaters of the customer homes A1 and A2 are turned on for the first one hour to boil a total of 400L of water. Next, in the latter two hours, the electric water heaters of the customer homes A3 and A4 are turned on to boil a total of 400L of water. According to this, 800 L of water was boiled in 2 hours, and a predetermined voltage suppression effect was achieved.

  FIG. 8 is a diagram illustrating an example of the electric water heater 61. Fig.8 (a) shows Example 1 of an electric water heater. The flow meter QF1 measures the amount of water supplied into the tank, and transmits water supply result data to the remaining water amount measuring unit every hour. The flow meter QF2 measures the amount of hot water used from the tank and transmits usage record data to the remaining water amount measuring unit every hour. The remaining water amount measurement unit receives the actual water supply data from the flow meter QF1, receives the actual use data from the flow meter QF2, and subtracts the actual use data from the actual water data to thereby determine the amount of water remaining in the tank. (Remaining water amount) is calculated and output to the communication unit. The communication unit acquires the residual water amount in the tank from the residual water amount measurement unit and transmits it to the voltage suppression processing device 7.

  FIG. 8B shows Example 2 of the electric water heater. The calculation method and the transmission method of the remaining water amount are the same as those of Example 1 in FIG. The difference from Example 1 is that the IH heater moves up and down by the rotation of a motor provided in the tank, so that, for example, water boiling in units of 5 to 10 liters can be realized. By reducing the diameter of the tank, water heating in units of 1 liter becomes possible.

  FIG. 9 is a diagram showing an embodiment of the ecocute 62. As a principle of boiling water, first, water (water temperature of about 20 ° C.) at the bottom of the tank is sent to a hot water supply heat exchanger by a circulation pump. The hot water supply heat exchanger passes through a gas that has been compressed by the compressor and has reached a high temperature, and the water that passes through the hot water supply heat exchanger is converted into hot water (hot water temperature of 40 to 90 ° C.). By adjusting the amount of water sent to the hot water supply heat exchanger by the circulation pump, it becomes possible to boil water in units of 1 liter. In addition, the calculation method and transmission method of the amount of remaining water are the same as that of Example 1 of the electric water heater of Fig.8 (a).

  The watt-hour meter with a communication function transmits the operation status of Ecocute to the voltage suppression processing device 7 at a remote location. On the other hand, when an operation command is received from the voltage suppression processing device 7, the hot water is forcibly boiled. Then, when the hot water in the tank reaches the set temperature, the hot water boiling is stopped.

  FIG. 10 is a diagram illustrating an example of a watt-hour meter with a communication function. The watt-hour meter with a communication function is connected between a power source and an electric water heater, receives an operation command or a stop command from the outside by a receiving unit, and turns on or off power feeding to the electric water heater. In addition, the operating status is transmitted to the outside by the transmitting unit. Note that the power supply can be turned on or off by the function of the electric water heater.

  In the above embodiment, in order to make each part in the voltage suppression processing device 7 shown in FIG. 2 function, a program executed by the processing unit 74 is recorded on a computer-readable recording medium, and the recorded program The voltage suppression processing device 7 according to the embodiment of the present invention is realized by causing the computer to read and execute the above. In this case, the program may be provided to the computer via a network such as the Internet, or a semiconductor chip or the like in which the program is written may be incorporated in the computer.

  According to embodiment of this invention demonstrated above, while suppressing the voltage rise of the high voltage distribution line 3 by the solar power generation device PV, the power sale by the solar power generation device PV can be continued.

  Specifically, since electric water heaters such as the electric water heater 61 and Ecocute 62 are used for the countermeasures for suppressing the voltage rise of the high-voltage distribution line 3, the cost for the countermeasures for voltage suppression can be reduced and It is possible to continue selling the generated power without restricting the power generation of the power generation device PV and the power supply to the outside of the house. And since the raised voltage can be accurately suppressed by utilizing the electric water heater, the voltage of the high-voltage distribution line 3 is maintained at an appropriate value even when the generated power of the photovoltaic power generation device PV increases. And can be operated.

  Furthermore, since the amount of power generated by the solar power generation device PV can be predicted, it is possible to adjust the operation of a thermal power plant or the like that supplies system power and reduce fuel costs. Next, there is a merit other than the installer of the photovoltaic power generator PV by implementing a discount on the customer's house 6 who cooperated in securing water for boiling in the electric water heater in advance. Arise. Then, the installer of the photovoltaic power generation device PV bears a part of the countermeasure cost for suppressing the rise of the distribution line voltage, and the contribution is paid to the customer home 6 of the electric water heater that cooperated with the voltage suppression countermeasure. Paying the balance between the two, the balance between the two can be balanced.

<< Other embodiments >>
As mentioned above, although the form for implementing this invention was demonstrated, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are also included in the present invention. For example, although the solar power generation device PV has been described in the above embodiment, other distributed power sources may be used, for example, a wind power generation device or a solar thermal power generation device.

1 Distribution system 2 Substation 3 High voltage distribution line (distribution line)
4 Measuring device (Voltmeter)
5 Low voltage line 61 Electric water heater (electric water heater)
62 Eco Cute (electric water heater)
7 Voltage suppression processing device 74 Processing unit 75 Storage unit 75A Power demand database (power demand)
75B Distribution line database (distribution line status)
75C Distribution line work plan database (distribution line status)
75B1 Low pressure tolerance (allowable voltage upper limit)
9 Weather information server (weather information)

Claims (6)

Means for storing an allowable voltage upper limit value that is an upper limit value of an allowable voltage range in the distribution line;
Means for obtaining a voltage value measured at each point from the voltmeter installed at each point of the distribution line;
Means for acquiring a countermeasure time which is a time required for a voltage suppression countermeasure for the distribution line;
When at least one of the acquired voltage values is larger than the allowable voltage upper limit value, a voltage drop is calculated by subtracting the allowable voltage upper limit value from a voltage value larger than the allowable voltage upper limit value. Select an electric water heater to be connected to the distribution line, and make the voltage value at the point of the distribution line within an allowable range based on the total power consumption of the electric water heater and the acquired countermeasure time. Means for calculating the amount of water required for heating,
Means for obtaining a remaining water amount that is the amount of water remaining in each tank of the electric water heater;
Means for allocating the amount of water in the water heater to each electric water heater based on the acquired amount of remaining water;
Means for instructing each electric water heater to which the amount of water is distributed;
A voltage suppression processing apparatus comprising: The voltage suppression processing device according to claim 1 ,
The means for allocating the amount of water in the water heater to each electric water heater is:
A voltage suppression processing apparatus characterized by preferentially selecting a distributed power source connected to the distribution line or an electric water heater in the vicinity of a substation that transmits system power to the distribution line. The voltage suppression processing device according to claim 1 or 2 ,
Based on weather information of the next day, power demand and distribution line status, means for predicting the time zone, point and voltage value at which the voltage value of the distribution line is greater than the allowable voltage upper limit by the distributed power source the next day;
Based on the predicted results, calculating the amount of water required for the next day, selecting an electric water heater to be heated the next day, and means for allocating the amount of water for the selected water heater to each selected electric water heater,
Means for instructing each electric water heater to which the amount of water of the water heater is allocated to secure water;
A voltage suppression processing apparatus, further comprising: A method of suppressing the voltage of the distribution line by a computer,
The computer
Storing an allowable voltage upper limit value that is an upper limit value of a voltage allowable range in the distribution line;
Obtaining a voltage value measured at each point from the voltmeter installed at each point of the distribution line;
Obtaining a countermeasure time which is a time required for a voltage suppression countermeasure for the distribution line;
When at least one of the acquired voltage values is larger than the allowable voltage upper limit value, a voltage drop is calculated by subtracting the allowable voltage upper limit value from a voltage value larger than the allowable voltage upper limit value. Select an electric water heater to be connected to the distribution line, and make the voltage value at the point of the distribution line within an allowable range based on the total power consumption of the electric water heater and the acquired countermeasure time. Calculating the amount of water required for heating,
Obtaining a residual water amount that is the amount of water remaining in each tank of the electric water heater;
Allocating the amount of hot water to each electric water heater based on the obtained amount of remaining water;
Instructing each electric water heater to which the amount of water is distributed,
The voltage suppression processing method characterized by performing. The voltage suppression processing method according to claim 4 ,
The computer
In the step of allocating the amount of water in the water heater to each electric water heater,
A voltage suppression processing method characterized by preferentially selecting a distributed power source connected to the distribution line or an electric water heater in the vicinity of a substation that transmits system power to the distribution line. The voltage suppression processing method according to claim 4 or 5 ,
The computer
Based on weather information on the next day, power demand and distribution line status, predicting a time zone, a point and a voltage value at which the voltage value of the distribution line is greater than the allowable voltage upper limit value by the distributed power source on the next day;
Based on the predicted result, calculating the amount of water required for the next day, selecting an electric water heater to be heated on the next day, and allocating the amount of water for the selected water heater to each selected electric water heater;
Instructing each electric water heater to which the amount of water of the water heater is allocated to secure water;
The voltage suppression processing method characterized by further performing.

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