Power control system

Abstract

To provide control of making states of charge of a plurality of units uniform taking into consideration conditions of the units.SOLUTION: A power control system includes a preprocessing section that obtains information in a plurality of units from each of the unit having power conversion capability, and calculates a total value of the power generation amount of photovoltaic power generation panels, a total value of the power storage residual amount of storage batteries, and a total value of charge discharge output of electric vehicles, an acquisition unit that obtains a first management command value of charge discharge output of a bidirectional DC / AC inverter and a second management command value of charge discharge output of all of the storage batteries, calculated using the total values on the basis of a predefined control modes for a prescribed management unit, and a calculation unit that selects one of the management command values for calculation according to a predetermined calculation pattern and calculates a command value for a charging and discharging command value proportional to the unit using a predetermined formula.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a power control system.

Background Art

[0002] There is a technique related to the control of a conventional PCS (Power Conditioning System). Note that the PCS is a device attached to distributed power sources such as solar panels and storage batteries mainly for the purpose of converting DC power and AC power.

[0003] For example, there is a technique related to a battery system that can control the SOC of batteries to be uniform among PCSs (see Patent Document 1). In this technique, the charge and discharge amounts of each AC / DC conversion device are determined based on the charge and discharge requirements, the number of battery modules, and the battery capacity ratio.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Conventionally, in many cases, a PCS is attached to a distributed power source on a one-to-one basis as described above. However, in recent years, the development of a device called "multi-PCS" that has a function of integrally controlling a plurality of distributed power sources (typical examples include a combination of solar panels, storage batteries, and EV chargers) in DC has been actively carried out. The multi-PCS is composed of a DC / AC inverter, a control unit, and a plurality of DC / DC converters, and has attracted attention due to its high charge and discharge efficiency and high stability of power supply during a power outage.

[0006] However, the prior art such as Patent Document 1 has the following problems. First, when calculating the charge and discharge command values for each storage battery in proportion to the storage capacity [kWh], there is a risk of emptying the storage batteries of some units first, such as giving a high-output discharge instruction to a storage battery with a large storage capacity but a small charge rate. Second, assumptions including other distributed power sources such as solar panels and chargers for electric vehicles are not made. Also, the prior art does not consider the effects such as output limitations by these power source groups and differences in control procedures due to the priority order of charge and discharge.

[0007] In consideration of the above facts, an object of the present invention is to enable control to equalize the SOC of the storage batteries of each unit by considering the states of a plurality of units.

Means for Solving the Problem

[0008] To achieve the above object, the power control system of the present invention acquires, from each of a plurality of units having a power conversion function, the power generation amount of a solar panel, the charge rate of a storage battery, the storage capacity of the storage battery, and the total charge and discharge output of an electric vehicle in the unit, and includes a preprocessing unit that calculates the total value of the power generation amounts of the solar panels, the total remaining storage amount of the storage batteries, and the total charge and discharge output of the electric vehicles. Further, the power control system includes an acquisition unit that acquires a first management command value for the charge and discharge output of a bidirectional DC / AC inverter and a second management command value for the charge and discharge output of the entire storage battery, which are calculated using the total values according to a control mode predetermined in a predetermined management unit. Also, the power control system selects, among the acquired first management command value and the second management command value, a management command value for calculation according to a predetermined calculation pattern, and for each of the units, uses a predetermined calculation formula based on the selected management command value for calculation, the charge rate of each of the units, the power generation power of the solar panel, the charge and discharge power of the electric vehicle, and the storage capacity of each of the units to calculate a charge and discharge command value to be allocated to the unit, and includes a calculation unit.

Effects of the Invention

[0009] According to the present invention, an effect is obtained in which control is enabled to equalize the SOC of the storage batteries of each unit in consideration of the states of a plurality of units.

Brief Description of the Drawings

[0010]

Figure 1

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Figure 12

Modes for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the background and problems of the prior art in this embodiment will be described. In this embodiment, an integrated power supply device composed of a bidirectional DC / AC inverter, a DC / DC converter, a bidirectional DC / DC converter, a control unit, a storage battery, a solar panel, an electric vehicle, and an EV charger is defined as a "multi-PCS". The power control system of this embodiment is a system premised on a multi-PCS. A configuration example of a single multi-PCS is shown in FIG. 1.

[0012] As described in the above problems, there are problems related to battery control in the prior art. When the multi-PCS is configured with multiple units, it is necessary to allocate the required output among multiple units. A method of allocating according to the ratio of the maximum output of each multi-PCS can be mentioned. In this case, if the remaining amount of the battery connected to some multi-PCS is low, it is conceivable that the remaining charge of that multi-PCS will become empty and the required output cannot be maintained.

[0013] FIG. 2 is a schematic diagram showing problems related to the battery control of the prior art. In the example of (a1), it is assumed that the instruction value from the EMS is a discharge of 60 kW. Here, when 60 kW is allocated according to the battery capacity [kWh], the instruction value of PCS1 is 20 kW and the instruction value of PCS2 is 40 kW. However, since the charge rate is not considered, the battery of PCS2 will become empty before that of PCS1. In this case, as in the example of (a2), it is assumed that PCS2 stops discharging and only 20 kW of discharge of PCS1 can be performed. Thus, when the remaining charge of one multi-PCS is lower than that of the other and the charge rate reaches the lower limit value and discharge becomes impossible, it will operate with only one unit and only the output of one unit can be obtained, and the output of the instruction value cannot be satisfied.

[0014] In this way, when configuring with multiple units, control is required to reduce the number of units that cannot respond to charge / discharge requests. Among the distributed power sources that make up the multi-PCS, especially the storage battery can store electric power for a long time, so it can be said that the management of the remaining amount of the storage battery is important. Therefore, control is required to issue charge / discharge instructions to each multi-PCS according to the remaining charge and available capacity of the storage battery.

[0015] In addition, the multi-PCS can set multiple control patterns based on the priority levels of each device and the combination of charge and discharge. For example, when the discharge priority levels within the multi-PCS are specified as (1) solar panels, (2) storage batteries, and the charge priority levels are (1) electric vehicles, (2) grid regeneration, the solar panels are discharged with the highest priority, and the electric vehicles are charged with the highest priority. In this control pattern, when the output of the solar panels alone is insufficient, the shortage is output from the storage batteries. Conversely, when the output of the solar panels is large and surplus power is generated, only the remaining power after charging the electric vehicles is regenerated to the grid. In this embodiment, such a control pattern combining priority levels and charge and discharge is defined as the "control mode".

[0016] Currently, many of the existing multi-PCS products are for medium-sized buildings (about 50 kW). However, in recent years, in order to respond to decarbonization, high-output products (over 100 kW) that can also be applied to large-scale buildings are expected. At that time, it is preferable to be able to construct an output with a high degree of freedom from medium scale to large scale by using one unit of a multi-PCS in the output range of about 50 kW as a unit and combining multiple units to achieve an output of 100 kW or more. On the other hand, even when configured with multiple units, it is necessary to devise a way to maintain the same operability as when introducing a single high-output machine.

[0017] FIG. 3 is a diagram conceptually showing the relationship between the EMS and the multi-PCS of this embodiment. Assuming that commands are issued individually as in (b1), the burden on the EMS is large. Therefore, as in (b2), it is preferable that the EMS can issue commands in a batch as commands for one virtual multi-PCS.

[0018] In this embodiment, a single multi-PCS is used as a unit, and a power supply system composed of a plurality of units with power conversion functions is targeted for control. Note that there is no limit on the number of units. Also, for various devices within the multi-PCS, even if the functions are the same, the performance values may differ for each unit. For example, when the power generation capacity of the solar panel of Unit 1 is 50 kW, the power generation capacity of the solar panel of Unit 2 may be 20 kW.

[0019] [First Embodiment] The first embodiment will be described. FIG. 4 is a diagram showing an example of the functional configuration of the power control system 1 of this embodiment. Note that the mechanical configurations of other embodiments after the first embodiment are the same. As shown at the top of FIG. 4, the power control system 1 includes an EMS (Energy Management System) 90, an integrated controller 100, and a plurality of multi-PCSs (102 1~N ). Note that when describing multi-PCSs in general, the reference signs will be omitted as appropriate for explanation. Current is indicated by a solid line and communication is indicated by a broken line. The configuration of each multi-PCS (102 1~N ) is the same as the configuration shown in FIG. 1.

[0020] Power from the grid power supply is supplied to a plurality of multi-PCSs (102 1~N ) from the voltage conversion facility 10 and the load 20. The current from the voltage conversion facility 10 to the multi-PCS is an alternating current (AC), and within the multi-PCS, it is a direct current (DC). Commands from the EMS 90 are output to the multi-PCS (102 1~N ) via the integrated controller 100. Also, in the power control system 1 of this embodiment, the case where the EMS 90 and the integrated controller 100 are separated will be described as an example, but an integrated configuration can also be adopted. Note that the EMS 90 is an example of the management unit of the present disclosure. The plurality of multi-PCSs are an example of the plurality of units of the present disclosure.

[0021] The EMS90 receives information such as the total generated power of multiple PCSs of solar panels from the integrated controller 100, and determines the control mode and command values for the integrated controller 100. Note that the control mode is specified by the EMS90, and the integrated controller 100 cannot specify the control mode. The integrated controller 100 collects information such as the power generation amount of solar panels from each multi-PCS and transmits the total value thereof to the EMS90. Also, when receiving command values from the EMS90, it calculates command values for each multi-PCS according to the control mode and transmits commands to each multi-PCS. By interposing the integrated controller 100, the multi-PCS group appears to the EMS90 as if it were a single multi-PCS instead of multiple units, and there is an advantage that individual instructions to each multi-PCS are not required and thus the EMS itself does not need to be modified.

[0022] The lower part of FIG. 4 is a diagram showing the functional configuration of the integrated controller 100. The integrated controller 100 includes a storage unit 110, a preprocessing unit 120, an acquisition unit 122, and a calculation unit 124. The storage unit 110 stores information collected from the multi-PCS and command values from the EMS. In the integrated controller 100, information communication is performed with each multi-PCS and the EMS in the processing of each unit, and necessary information is appropriately acquired.

[0023] The outline of the integrated control by the integrated controller 100 will be described. (1) According to the remaining charge amount and available capacity of the batteries in each multi-PCS instead of the battery capacity, command values for the input and output to the batteries and DC / AC inverters in each multi-PCS are calculated from the integrated controller. Thereby, the remaining charge amount (SOC) of the batteries in each multi-PCS is made as uniform as possible. (2) Considering the solar panels and electric vehicles in each multi-PCS, command values for the input and output to the batteries, electric vehicles, and DC / AC inverters in each multi-PCS are determined from the integrated controller.

[0024] The integrated controller 100 is configured as a device and is realized by a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores programs for realizing each processing routine, etc., a RAM (Random Access Memory) that temporarily stores data, a memory as storage means, and a network interface, etc. Note that depending on the suitability of each process, a GPGPU or an accelerator may be used instead of the CPU, and an arithmetic unit suitable for the process may be used as appropriate. Particularly when performing processes related to learning and inference, it is preferable to use a GPGPU or an accelerator. The EMS90 can also be configured as a similar device.

[0025] Here, examples of the rules and various information used in the control of the integrated controller 100 will be listed and explained.

[0026] (Rule) In any mode, calculations are performed based on the following rules. · The generated power of the solar panel shall be output with the highest priority. Therefore, the integrated controller does not issue a command for the output of the solar panel. · The priority order of charging / discharging of the electric vehicle is switched for each mode. Specifying whether charging is possible is possible from the EMS (it is not possible with the integrated controller 100). · For all devices, calculations are performed with the charging side as positive and the discharging side as negative. For example, the charging of an electric vehicle or a storage battery is a positive number, the discharging of a solar panel or a storage battery is a negative number. When inputting from the grid, it is positive, and when regenerating, it is negative. Also, since the solar panel is only for discharging, it is always a negative number.

[0027] (Legend) The legend of the formula is as follows. Note that the command value from the EMS90 to the integrated controller 100 is defined as a management command value (described later) and is distinguished from the command value from the integrated controller 100 to the multi-PCS. Total generated power of the solar panel: a [kW] Generated power of the solar panel in each multi-PCS: a i [kW] State of charge of the battery in each multi-PCS: b i [%] Battery capacity of the battery in each multi-PCS: c i [kWh] Total charge and discharge output of the electric vehicle: d [kW] Charge and discharge output command value of the electric vehicle: d cv [kW] (d cv is instructed from the EMS to the integrated controller) Total charge and discharge output of the electric vehicle in each multi-PCS: d i [kW] Charge and discharge output of the charger of each electric vehicle: d j [kW] Tentative charge and discharge output of the charger of each electric vehicle: d j_tent [kW] Total output of each multi-PCS: f [kW] Command value instructed from the EMS to the integrated controller: f cv [kW] Output of each multi-PCS: f i [kW] Recalculation command value to the integrated controller: f rd [kW] Proportion calculation command value to the electric vehicle: f ev [kW] Proportion calculation command value to the battery: f bat [kW] Proportion recalculation command value to the battery: f bat_rd [kW] (f bat is for the system regeneration specified_EV priority mode) Total discharge output of the battery: h [kW] Discharge command value of the battery instructed from the EMS to the integrated controller: h cv [kW] Discharge output of the battery in each multi-PCS: h i [kW] Tentative discharge output of the storage battery in each multi-PCS: h i_tent [kW] Recalculation discharge command value to the battery: h rd [kW] Output upper limit of the electric vehicle charger in each multi-PCS: k j [kW] (k j > 0) Number of electric vehicle chargers: l [units] Output upper limit of the battery in each multi-PCS: m i [kW] Number of multi-PCS: n [units] Input / output upper limit of each multi-PCS: q i [kW] (q i > 0)

[0028] Also, various values related to electric vehicles have the following relationships. d = Σ i=1 n d i d = Σ j=1 l d j

[0029] Figure 5 is an example of the control flow of the power control system. The integrated controller 100 will be mainly described.

[0030] In step S80, each multi-PCS transmits data to the integrated controller 100. The integrated controller 100 obtains the power generation amount a i [kW], the battery charge rate b i [%], the battery storage capacity c i [kWh], and the total d i [kW] of the charging / discharging output of the electric vehicle.

[0031] In step S90, the integrated controller 100 (preprocessing unit 120) calculates the power generation amount of the solar panel, the remaining battery storage amount, the charging / discharging output of the electric vehicle, and the respective total values a [kW], bc [kWh], d [kW] based on the acquired information. The integrated controller 100 transmits the calculated values (a, bc, d) to the EMS90.

[0032] In step S92, based on the value obtained from the integrated controller 100 and the building load, the EMS 90 determines the control mode and calculates the management command value for the integrated controller 100. The EMS 90 transmits the calculated management command value to the integrated controller 100. Here, in this embodiment, the management command value calculated and transmitted by the EMS 90 is the (f cv ) in the above-mentioned exemplification as the first management command value for the charge and discharge output of the bidirectional DC / AC inverter, and the (h cv ) as the second management command value for the charge and discharge output of the entire battery. Also, the charge and discharge output command value (d cv ) of the electric vehicle may be used as the third management command value.

[0033] In step S100, the integrated controller 100 (acquisition unit 122) acquires the management command values (first management command value, second management command value, third management command value) from the EMS 90.

[0034] In step S102, the integrated controller 100 (calculation unit 124) calculates the charge and discharge command values to be allocated to each multi-PCS using the command value from the EMS 90.

[0035] In the calculation of the command values to be allocated, according to the allocation calculation pattern described later, the management command value for the calculation of either the first management command value f cv , or the second management command value h cv is selected. For each of the multi-PCS, using a predetermined calculation formula, the charge and discharge command values to be allocated to the multi-PCS are calculated. The calculation formula is based on the selected management command value for the calculation (f cv , or h cv ), the charge rate of the battery in the multi-PCS, the generated power of the solar panel, the charge and discharge power of the electric vehicle, and the storage capacity of the battery in the multi-PCS. The detailed content of the calculation of the command value will be described later.

[0036] In step S104, the integrated controller 100 (calculation unit 124) outputs the calculated command values to each multi-PCS.

[0037] In step S82, each multi-PCS executes charge and discharge based on the received command value.

[0038] (Pattern of proportional calculation of command value) Here, regarding the details of the proportional calculation of the command value for each multi-PCS, the control mode is divided into the following 7 patterns based on the charging and discharging of electric vehicles. In this embodiment, for each pattern, a calculation formula is proposed. The first to fourth patterns are for the case where the electric vehicle is charging, and the fifth to seventh patterns are for the case where the electric vehicle is discharging.

[0039] · First pattern: When specifying the regenerative power from the multi-PCS to the grid (grid regeneration specification mode). Assumed usage scenarios: Peak shaving, DR, etc. · Second pattern: When specifying the discharge power from the battery of the multi-PCS (battery discharge power specification mode) Assumed usage scenarios: Since the generation of surplus power from sunlight is predicted, it is desired to discharge from the battery in advance to create free capacity, etc. · Third pattern: When specifying the input power from the grid to the multi-PCS (grid input specification mode). Assumed usage scenarios: Surplus power is generated in a building where a solar panel is separately connected in addition to the multi-PCS, etc. · Fourth pattern: When specifying the input power to the battery of the multi-PCS (battery charging power specification mode). Assumed usage scenarios: To increase the remaining battery capacity in preparation for peak shaving, etc. · Fifth pattern: When specifying the regenerative power from the multi-PCS to the grid and giving a higher priority to the discharge of the electric vehicle than the battery (grid regeneration specification_EV priority mode). Assumed usage scenarios: When it is desired to actively utilize the electric vehicle for peak shaving, DR, etc. · Sixth pattern: When specifying the regenerative power from the multi-PCS to the grid and giving a higher priority to the battery than the discharge of the electric vehicle (grid regeneration specification_battery priority mode). Assumed usage scenarios: When it is desired to perform peak shaving, DR, etc. while conserving the power of the electric vehicle for movement. · Pattern 7: Specify the discharge power from the EV of the multi-PCS and do not discharge from the battery (Battery discharge power specified_EV priority mode). Assumed usage scenario: Since the generation of surplus solar power is predicted, it is desired to create free capacity in the EV preferentially, etc.

[0040] In addition, for example, in a mode where system regeneration is specified, when the building's power demand is likely to exceed the target demand, it is assumed that the multi-PCS will cut that amount of peak. Under such an assumption, the EMS90 determines the control mode specification and management command value of the multi-PCS.

[0041] As described above, the control mode of the EMS90 (management unit) determines the priority order of the inputs and outputs of the solar panel, battery, and electric vehicle in order to perform the desired operation of each multi-PCS for a predetermined usage scenario of the assumed multi-PCS, and also determines a predetermined calculation pattern corresponding to the priority order. In addition, the calculation of the command value of the multi-PCS is performed using a calculation formula of a predetermined calculation pattern determined in advance for the control mode. The details of the calculation based on these patterns will be described separately for each embodiment.

[0042] (Pattern 1) Pattern 1 is the case of the system regeneration specified mode (when the electric vehicle is charging). The calculation procedure of the command value to each multi-PCS will be described. In this mode, the priority order of discharge is (1) solar panel, (2) battery, and the priority order of charging is (1) charging of the electric vehicle, (2) system regeneration. The calculation is as follows.

[0043] 1. The integrated controller that has received the management command value f cv from the EMS calculates the temporary discharge command value h i_tent to the battery in each multi-PCS according to the following formula (1).

Equation

[0044] 2. Next, calculate the discharge command value h to the battery in each multi-PCS according to formula (2). i Calculate it.

Equation

[0045] Since there are output limits for other distributed power sources and DC / AC inverters, the power that can be discharged from the battery is limited. Therefore, formula (2) compares the output limit of the battery considering the power generation of the solar panel, the charging output of the electric vehicle, and the output limit of the multi-PCS with the value calculated in step 1. If the temporary discharge command value h to the battery in the multi-PCS i exceeds the battery output limit (h i <-q i_tent -a i -a i ), the discharge command value h to the battery of the multi-PCS i shall be -q i -a i -a i .

[0046] Figure 6 is a diagram showing an example of the input / output flow of the multi-PCS of the first embodiment. Assume that there is a limit with the bidirectional DC / AC inverter. At this time, since the output of the solar panel a and the output of the battery h flow in the grid direction, the limit value of formula (2) is -q i -a i .

[0047] 3. In the case of 2 above, since there is a battery output limit, it is necessary to have other multi-PCSs bear the insufficient output. Calculate the command value f i to units other than the multi-PCS according to formula (3) (f rd = f rd -h cv -h i ). Then, replace f cv in formula (1) with f rd and calculate. Then calculate according to formula (2). Also, h i_tent <-q i -a iMultiple multi-PCS may exist. The details of the calculation example will be described later.

Number

[0048] 4. Calculate the output f of each multi-PCS according to formula (4). i Calculate.

Number

[0049] 5. Repeat the above steps 1 to 4 until formula (5) is satisfied.

Number

[0050] (Calculation example) Fig. 7 shows an example of the procedure for calculating the command value for each multi-PCS. Steps 1 to 5 are as described above. Assume a case of integrally controlling three multi-PCS, which are respectively multi-PCS1, multi-PCS2, and multi-PCS3. The calculation conditions are that the management command value f cv to the integrated controller 100 of EMS90, in the case of the system regeneration designation mode, the discharge output is f cvLet it be 120 [kW]. The conditions of the integrated controller 100 are: the power generation amount a of the solar panel is 30 [kW], the remaining charge amount b×c of the storage battery is 125 [kW], and the charging output d of the electric vehicle is 0 [kW]. For Multi-PCS 1, the upper limit value q1 of the output is 50 [kW], the power generation amount a1 of the solar panel is 10 [kW], the storage capacity c1 of the storage battery is 100 [kWh], the charging rate b1 is 75 [%], and the charging output d1 of the electric vehicle is 0 [kW]. For Multi-PCS 2, q2 = 50 [kW], the power generation amount a2 of the solar panel is 10 [kW], the storage capacity c2 of the storage battery is 100 [kWh], the charging rate b2 is 25 [%], and the charging output d2 of the electric vehicle is 0 [kW]. For Multi-PCS 3, q3 = 50 [kW], the power generation amount a3 of the solar panel is 10 [kW], the storage capacity c3 of the storage battery is 100 [kWh], the charging rate b3 is 25 [%], and the charging output d3 of the electric vehicle is 0 [kW].

[0051] As described in the above calculation example, the integrated controller 100 calculates the command value. Here, the calculation modes of the integrated controller 100 including each of the following embodiments are summarized.

[0052] In the calculation of the calculation unit 124 of the integrated controller 100, for each unit that is a Multi-PCS, when calculating the temporary command value (h i_tent ) to the storage battery, as a predetermined calculation pattern, the first calculation pattern or the second calculation pattern is used. Note that which calculation pattern it is depends on whether the first management command value f cv is used in the calculation from step 1., in which case it is the first calculation pattern, and when the second management command value h cv is used, it is the second calculation pattern.

[0053] When the calculation unit 124 uses the first calculation pattern, the management command value for calculation is the first management command value f cv and the first management command value f cvFrom this, considering the priorities regarding the photovoltaic power generation output, the charge / discharge output of the electric vehicle, and the charge / discharge output of the storage battery for each unit, the total value (a, b, c, d) of the charge / discharge output of the storage battery for each unit is calculated. Also, the calculation result obtained by apportioning the total value according to the remaining charge or available capacity of each storage battery is used as the provisional command value h i_tent for the charge / discharge output of the storage battery for each unit.

[0054] When using the second calculation pattern, the calculation unit 124 sets the management command value for calculation as the second management command value h cv and calculates, as the provisional command value for the charge / discharge output of the storage battery for each unit, the calculation result obtained by apportioning the second management command value h cv according to the remaining charge or available capacity of each storage battery.

[0055] In the calculation, the units for which the provisional command value calculated by the first calculation pattern or the second calculation pattern satisfies a predetermined condition are specified as target units.

[0056] When there are no target units that satisfy the predetermined condition, the calculation unit 124 does not perform recalculation of the charge / discharge command value. When there are target units, recalculation is performed. In the recalculation, for the specified target units, a recalculation command value is calculated by subtracting the charge / discharge output value (h cv or h cv ) of the storage battery of the target unit from the management command value (f i ) for calculation corresponding to the calculation pattern used, and the charge / discharge command value (f i ) for other units other than the target units is recalculated repeatedly. The calculation of the recalculation command value corresponds to, for example, Equation (3), Equation (7), and Equation (17).

[0057] Also, the predetermined condition in the calculation unit 124 is, for each unit, the absolute value of the power that the storage battery can input / output, calculated from the generated power (a) of the solar panel or the charge / discharge power (d) of the electric vehicle and the input / output upper limit (q) of the unit, in accordance with a predetermined priority for the control mode of the management unit (for example, h i) Determine whether the absolute value of the provisional command value is greater than that of , and identify the unit for which it is determined to be greater as the target unit. Note that the input / output upper limit (q) of the unit is, for example, the sum of the output of the solar panel, the power that the storage battery can input / output, and the input / output of the electric vehicle.

[0058] [Second Embodiment]: (Second Pattern) Next, the calculation procedure of the second pattern of the second embodiment will be described. The second pattern is the case of the storage battery discharge power designation mode (when the electric vehicle is charging). In this mode, the priority order of discharge is (1) solar panel, (2) storage battery, and the priority order of charging is (1) charging of the electric vehicle, (2) system regeneration. The following procedures can be implemented by partially re-reading the procedures of the first embodiment (the same applies to each subsequent embodiment by appropriately re-reading the procedures).

[0059] 1. The integrated controller 100 that has received the total h of the discharge command values of the storage battery from the EMS cv calculates the provisional discharge command value h i_tent to the storage battery in each multi-PCS according to Equation (6).

Equation

[0060] 2. Calculate the discharge command value h i to the storage battery in each multi-PCS according to Equation (2). Since there are upper limits on the output of other distributed power sources and DC / AC inverters, the power that can be discharged from the storage battery is limited. Therefore, Equation (2) compares the power generation power of the solar panel, the output limit of the storage battery considering the output upper limit of the multi-PCS, and the value calculated in step 1. If the provisional discharge command value h i to the storage battery in the multi-PCS i_tent exceeds the storage battery output limit (h i_tent < -q i -a i ), the discharge command value h i to the storage battery of the multi-PCS i is -q i -a iLet it be so.

[0061] Fig. 8 is a diagram showing an example of the input / output flow of the multi-PCS according to the second embodiment. Assume that there is a limit imposed by the bidirectional DC / AC inverter. At this time, since the power flowing in the grid direction is the output a of the solar panel and the output h of the storage battery, the limit value in Equation (2) is -q i -a i and it becomes so.

[0062] 3. In the case of the above 2., since there is a limit on the output of the storage battery, it is necessary to have other multi-PCS bear the insufficient output. According to Equation (7), calculate h i as the command value to units other than the multi-PCS. Then, replace h in Equation (6) with h rd and calculate. Then calculate according to Equation (2). Also, there may be multiple multi-PCS for which h rd <-q i_tent -a i holds. i There may be multiple multi-PCS for which this holds.

Number

[0063] 4. Calculate the command value f i for each multi-PCS according to Equation (4). 5. Repeat the above steps 1 to 4 until Equation (8) is satisfied.

Number

[0064] [Third Embodiment]: (Third Pattern) Next, the calculation procedure of the third pattern of the third embodiment will be described. The third pattern is the case of the grid input specified mode (when an electric vehicle is charging). In this mode, the discharge priority is (1) solar panel, (2) grid input, and the charge priority is (1) charging of the electric vehicle, (2) charging of the storage battery.

[0065] Here, in the calculation procedure of the command value for each multi-PCS of the first embodiment, with Equation (1) replaced by Equation (9) and Equation (2) replaced by Equation (10) in the text, -q i -a i is read as q i -d i , h i_tent <-q i -a i is read as h i_tent >q i -d i and the conditional expression (f cv ≦-Σ i=1 ^ n q i ) in Equation (5) is read as (f cv ≦Σ i=1 n q i ).

Number

Number

[0066] Figure 9 is a diagram showing an example of the input / output flow of the multi-PCS of the third embodiment. Assume that there is a restriction on the bidirectional DC / AC inverter. At this time, since the output d of the electric vehicle and the output h of the storage battery flow in the multi-PCS direction, the limit value in Equation (10) is q i -d i .

[0067] [Fourth Embodiment]: (Fourth Pattern) Next, the calculation procedure of the fourth pattern of the fourth embodiment will be described. The fourth pattern is the case of the storage battery charging power designation mode (when the electric vehicle is charging). In this mode, the discharge priority order is (1) solar panel, (2) grid input, and the charging priority order is (1) charging of the electric vehicle, (2) charging of the storage battery).

[0068] Here, in the calculation procedure of the command value for each multi-PCS in the second embodiment, Equation (6) is replaced with Equation (11), Equation (7) is replaced with Equation (10), and -q in the text i -a i is replaced with q i -d i , h i_tent <-q i -a i is replaced with h i_tent >q i -d i and read as such. Also, the conditional expression (h cv ≦-Σ i=1 n m i ) in Equation (8) is read as (h cv ≦Σ i=1 n m i ).

Number

[0069] Figure 10 is a diagram showing an example of the input / output flow of the multi-PCS in the fourth embodiment. Assume that there is a restriction on the bidirectional DC / AC inverter. At this time, since the power flowing in the multi-PCS direction is the output d of the electric vehicle and the output h of the storage battery, the limit value in Equation (10) is q i -d i .

[0070] [Fifth Embodiment] (Fifth Pattern) Next, the calculation procedure of the fifth pattern in the fifth embodiment will be described. In the fifth pattern, in this mode, the priority order of discharging is (1) solar panel, (2) discharging of the electric vehicle, (3) discharging from the storage battery, and the priority order of charging is (1) system regeneration. The following procedure is adopted for this pattern.

[0071] 1. The integrated controller 100 that has received the management command value f cv from the EMS90 calculates the provisional discharge output d of each electric vehicle according to Equation (12) j_tentCalculate it. Since Equation (12) distributes the command value by the number of units to electric vehicles, the command value is the same for each electric vehicle.

Number

[0072] 2. Calculate the charge-discharge output d of each electric vehicle according to Equation (13). j Since there is an output upper limit for the DC / DC inverter of the charger, the power that can be discharged from the electric vehicle is limited. Therefore, Equation (13) compares the output upper limit of the charger of the electric vehicle with the value calculated in Step 1. If the temporary discharge command value d j to the charger j of the electric vehicle exceeds the output upper limit of the charger of the electric vehicle (d j_tent < -k j ), the charge-discharge output d j of each electric vehicle becomes -k j .

Number

[0073] 3. In the case of the above 2., since the output of the charger of the electric vehicle is limited, it is necessary to let the battery bear the insufficient output. Calculate f bat as the command value to the battery in the multi-PCS according to Equation (14).

Number

[0074] 4. Calculate the temporary discharge command value h i_tent to the battery in each multi-PCS according to Equation (15).

Number

[0075] 5. Calculate the discharge command value h to the battery in each multi-PCS according to Equation (16). i Since there are output limits for other distributed power sources and the DC / AC inverter, the power that can be discharged from the battery is limited. Therefore, Equation (16) compares the power generated by the solar panels, the discharge output of the electric vehicle, the output limit of the multi-PCS, and the output limit of the battery considering these factors with the value calculated in Step 4. If the temporary discharge command value h i to the battery in the multi-PCS i exceeds the battery output limit (h i_tent < -q i -a i -d i ), the discharge command value h i to the battery in the multi-PCS i is set to -q i -a i -d i .

Equation

[0076] 6. In the case of the above 5., since the battery output is limited, it is necessary to have other multi-PCSs bear the insufficient output. Calculate the command value f i to the units other than the multi-PCS according to Equation (17). Then, replace f bat_rd in Equation (15) with f bat and perform the calculation. Then, calculate according to Equation (16). At this time, there may be multiple multi-PCSs for which h bat_rd < -q i_tent -a i -d i -d i .

Equation

[0077] 7. Calculate the command value f i to each multi-PCS according to Equation (4). 8. Calculate the regenerative power to the grid according to Equation (5).

[0078] FIG. 11 is a diagram showing an example of the input / output flow of the multi-PCS according to the fifth embodiment. It is assumed that there is a limit on the bidirectional DC / AC inverter. At this time, since the outputs flowing in the grid direction are the output a of the solar panel and the output d of the electric vehicle, the limit value in Equation (16) is -q i -a i -d i and becomes 。

[0079] [Sixth Embodiment] (Sixth Pattern) Next, the calculation procedure of the sixth pattern of the sixth embodiment will be described. The sixth pattern is the case of grid regeneration specified - battery priority mode (when the electric vehicle discharges). The priority order of discharge is (1) solar panel, (2) discharge from the battery, (3) discharge of the electric vehicle, and the priority order of charging is (1) grid regeneration. The following procedure is adopted for this pattern.

[0080] 1. The integrated controller that has received the command value f cv from the EMS calculates the provisional discharge command value h i_tent to the battery in each multi-PCS according to Equation (18). [Equation] ···(18)

[0081] 2. Calculate the discharge command value h i to the battery in each multi-PCS according to Equation (19). Since there are output limits for other distributed power sources and the DC / AC inverter, the power that can be discharged from the battery is limited. Therefore, Equation (19) compares the generated power of the solar panel, the output limit of the battery considering the output limit of the multi-PCS, and the value calculated in step 1. If the provisional discharge command value h i to the battery in the multi-PCS i exceeds the battery output limit (h i_tent < -q i -a i ), the multi-PCS iDischarge command value h for the storage battery i is -q i -a i shall be set.

Equation

[0082] 3. Calculate the total discharge value from the storage battery of each multi-PCS according to Equation (20).

Equation

[0083] 4. If the power discharged from the storage battery is insufficient, discharge from the electric vehicle. Therefore, calculate the proportional calculation command value f for the electric vehicle according to Equation (21). ev shall be calculated.

Equation

[0084] 5. Calculate the temporary proportional command value d for the electric vehicle in each multi-PCS according to Equation (22). j_tent shall be calculated.

Equation

[0085] 6. Calculate the charge-discharge output d of each electric vehicle according to Equation (13). Equation (13) takes into account the output upper limit of the charge-discharge device of the electric vehicle. If the temporary discharge command value d for the charge-discharge device j of the electric vehicle j exceeds the output upper limit of the charge-discharge device of the electric vehicle (d j_tent <-k j_tent <-k j ), the charge-discharge output d of each electric vehicle j shall be -k j shall be set.

[0086] 7. Calculate the command value f for each multi-PCS according to Equation (4). i to be calculated. 8. Calculate the regenerative power to the system according to Equation (5).

[0087] In the input / output flow of the multi-PCS of the sixth embodiment, the priorities in FIG. 11 are swapped.

[0088] [Seventh Embodiment]: (Seventh Pattern) Next, the calculation procedure of the seventh pattern of the seventh embodiment will be described. The seventh pattern is the case of the battery discharge power designation_EV priority mode (when the electric vehicle discharges). In this mode, the discharge priority is (1) solar panel, (2) discharge of the electric vehicle, and the charge priority is (1) system regeneration.

[0089] 1. The integrated controller that has received the command value d_cv from the EMS calculates the temporary discharge output d of each electric vehicle according to Equation (23). j_tent Equation (23) distributes the command value by the number of electric vehicles, so the command value is the same for each electric vehicle. [Equation] ···(23)

[0090] 2. Calculate the charge / discharge output d of each electric vehicle according to Equation (13). j Equation (13) takes into account the output upper limit of the electric vehicle charger. If the temporary discharge command value d j to the electric vehicle charger j exceeds the output upper limit of the electric vehicle charger (d j_tent < -k j ), the charge / discharge output d j of each electric vehicle is -k j .

[0091] 3. Calculate the total d of the discharge outputs of the electric vehicles according to Equation (24). [Equation] ···(24)

[0092] FIG. 12 is a diagram showing an example of the input / output flow of the multi-PCS according to the seventh embodiment. Since the discharge of the storage battery is stopped, only the discharge output of the electric vehicle needs to be determined.

[0093] As described above, according to the power control system according to each embodiment of the present invention, it is possible to perform control to make the SOCs of the storage batteries of the respective units uniform in consideration of the states of the plurality of units. In this method, (1) in the method of allocating command values to each multi-PCS, not only the storage capacity of the storage battery but also the charging rate is considered. As a result, it is possible to perform control to reduce the number of units that cannot respond to charge / discharge requests, and the risk of a decrease in the maximum output is reduced. (2) In the method of allocating command values to each multi-PCS, the charge / discharge of the solar panel and the electric vehicle are also considered. As a result, the high charge / discharge efficiency of the multi-PCS can be maximally utilized, and appropriate allocation of the command values becomes possible.

[0094] Note that the present invention is not limited to the above-described embodiments, and various modifications and applications are possible without departing from the gist of the present invention.

Description of Reference Numerals

[0095] 1 Power control system 90 EMS (Management unit) 100 Integrated controller 102 Multi-PCS (Unit) 110 Storage unit 120 Preprocessing unit 122 Acquisition unit 124 Calculation unit

Claims

1. From each of a plurality of units having a power conversion function, obtain, in the unit, the power generation amount of the solar panel, the charging rate of the storage battery, the storage capacity of the storage battery, and the total charge and discharge output of the electric vehicle, and calculate the total value of the power generation amount of the solar panel, the total remaining storage amount of the storage battery, and the total charge and discharge output of the electric vehicle. A preprocessing unit, An acquisition unit that acquires a first management command value for the charge and discharge output of the bidirectional DC / AC inverter and a second management command value for the charge and discharge output of the entire storage battery, which are calculated using the total value according to a control mode predetermined in a predetermined management unit; Among the acquired first management command value and the second management command value, select a management command value for calculation according to a predetermined calculation pattern, and for each of the units, the selected management command value for calculation, the charging rate of each of the units, the power generation power of the solar panel, the charge and discharge power of the electric vehicle, and a calculation unit that calculates a charge and discharge command value allocated to the unit using a predetermined calculation formula based on the storage capacity of each of the units; A power control system including.

2. The control mode of the management unit determines the priority order of the inputs and outputs of the solar panel, the storage battery, and the electric vehicle in order to perform the desired operations of each unit for a predetermined usage situation of the assumed unit, and determines the predetermined calculation pattern corresponding to the priority order. The calculation of the command value of the unit is performed using the calculation formula of the predetermined calculation pattern predetermined for the control mode. The power control system according to claim 1.

3. When calculating a temporary command value for each of the units, use the first calculation pattern or the second calculation pattern as the predetermined calculation pattern. When using the first calculation pattern, use the management command value for calculation as the first management command value, and from the first management command value, considering the priority order regarding the solar power generation output, the electric vehicle charge and discharge output, and the storage battery charge and discharge output of each unit, calculate the total value of the storage battery charge and discharge output of each unit, and calculate the calculation result obtained by allocating the total value according to the remaining storage amount or free capacity of each storage battery as the temporary command value of the storage battery charge and discharge output of each unit. When using the second calculation pattern, the management command value for calculation is set as the second management command value, and a calculation result obtained by proportionally dividing the second management command value according to the remaining charge amount or available capacity of each storage battery is calculated as a provisional command value for the charge / discharge output of the storage battery of each unit. Identify, as target units, the units for which the provisional command value calculated according to the first calculation pattern or the second calculation pattern satisfies a predetermined condition. When there are no target units that satisfy the predetermined condition, the recalculation of the charge / discharge command value is not performed. When there are target units, for the identified target units, calculate a command value for recalculation by subtracting the charge / discharge output value of the storage battery of the target unit from the management command value for calculation according to the calculation pattern used, and repeatedly recalculate the charge / discharge command value for units other than the target units. The power control system according to claim 2.

4. The predetermined condition in the calculation unit is, for each of the units, to determine whether the absolute value of the provisional command value is greater than the absolute value of the power that the storage battery can input / output, which is calculated from the generated power of the solar panel or the charge / discharge power of the electric vehicle and the input / output upper limit of the unit, according to a predetermined priority order with respect to the control mode of the management unit, and identify the units for which it is determined to be greater as the target units. The power control system according to claim 3.

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