Charging device and power system

Abstract

To provide a charging device in which energy management can be performed even if an electric automobile that is not designed for dynamic control is connected.SOLUTION: A charging device A1 is configured to charge a storage battery 21 of an electric automobile 2 that travels by driving a motor with power of the storage battery 21. The charging device includes a DC power source unit 11 that outputs DC power, and a control unit 16 that controls the DC power source unit 11. The control unit 16 includes a deviation detection unit 162 that detects a deviation state in which a power detection value Pout obtained by detecting the output power from the DC power source unit 11 is deviated from a defined power command value Pref, a stop command unit 163 that stops the output from the DC power source unit 11 when the deviation detection unit 162 detects the deviation state, and a start command unit 161 that starts the output from the DC power source unit 11 after the elapse of a stop time from the output stop performed by the stop command unit 163.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a charging device for charging an electric vehicle or the like, and to a power system including the charging device. [Background technology]

[0002] In recent years, with the spread of electric vehicles, the development of quick chargers that supply DC power to electric vehicles and charge storage batteries has progressed. Techniques for utilizing quick chargers in energy management have also been developed. Patent Document 1 discloses a power management system for charging that includes a distributed power source, a secondary battery, a power adjustment device that controls the input and output of power between the distributed power source and the secondary battery, a power management device that controls the power adjustment device, and a quick charger. The power adjustment device performs energy management by controlling the power adjustment device so that the power at the interconnection point does not deviate from a specified range. In this power management system, a quick charger can also be used for energy management.

[0003] When using a quick charger for energy management, it is necessary to be able to change the charging power to the connected electric vehicle. The dynamic control function in the CHAdeMO (registered trademark) standard is a function that allows the quick charger to request changes to the charging power to the electric vehicle in real time. Therefore, by using the dynamic control function to change the charging power, the quick charger can perform energy management. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-31243 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if an electric vehicle that does not support dynamic control is connected to a quick charger, the quick charger cannot change the charging power to the electric vehicle, and in this case, the quick charger cannot perform energy management.

[0006] The present invention was conceived in light of the above circumstances, and its object is to provide a charging device that can perform energy management even when an electric vehicle that does not support dynamic control is connected. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides the following technical means.

[0008] A charging device provided by a first aspect of the present invention is a charging device that charges a storage battery of an electric vehicle that moves by driving an electric motor with power from the storage battery, and includes a DC power supply unit that outputs DC power, and a control unit that controls the DC power supply unit, and the control unit includes a deviation detection unit that detects a deviation state in which a power detection value detected as the output power of the DC power supply unit deviates from a set power command value, a stop instruction unit that causes the DC power supply unit to stop output when the deviation detection unit detects the deviation state, and a start instruction unit that causes the DC power supply unit to start output after a stop time has elapsed since the output was stopped by the stop instruction unit.

[0009] In a preferred embodiment of the present invention, the deviation detection unit detects the deviation state when a state in which the power difference between the detected power value and the power command value is equal to or greater than a first threshold value continues for a determination time or longer.

[0010] In a preferred embodiment of the present invention, the deviation detection unit detects the deviation state when a power difference between the detected power value and the power command value becomes equal to or greater than a second threshold value.

[0011] In a preferred embodiment of the present invention, the control unit stores a power command value when the stop instruction unit stops the output of the DC power supply unit, and uses the stored power command value when the start instruction unit starts output of the DC power supply unit after the stop time has elapsed.

[0012] A power system provided by a second aspect of the present invention is a power system comprising a charging device provided by the first aspect of the present invention and a centralized management device that manages a plurality of power devices including the charging device, wherein the centralized management device calculates a guide index for controlling overall power, which is the current input / output power of the entire power system, to an overall target value and transmits the guide index common to the plurality of power devices, and the control unit of the charging device calculates the power command value based on an optimization problem using the received guide index. [Effects of the Invention]

[0013] According to the present invention, when the deviation detection unit detects a deviation between the power detection value and the power command value, the stop instruction unit stops output from the DC power supply unit, and after a stop time has elapsed since the output was stopped, the start instruction unit starts output from the DC power supply unit. When charging is resumed, the power target value is reset based on the power command value. As a result, the charging device according to the present invention can change the power target value based on the power command value even when an electric vehicle that does not support dynamic control is connected, thereby enabling energy management.

[0014] Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a block diagram showing the overall configuration of a power system including a charging device according to a first embodiment. [Figure 2] 10 is an example of a flowchart illustrating a charging process performed by a control unit. [Figure 3]6 is a time chart for explaining the change over time in the detected power value due to the charging process performed by the control unit. [Figure 4] FIG. 10 is a diagram showing a simulation result when an electric vehicle that does not support dynamic control is connected to the charging device. [Figure 5] 10 is a time chart for explaining a modified example of the deviation detection unit. [Figure 6] FIG. 10 is a block diagram showing the overall configuration of a power system including a charging device according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0017] [First embodiment] FIG. 1 is a block diagram showing the overall configuration of a power system B1 equipped with a charging device A1 according to a first embodiment. The power system B1 is connected to a power grid and is capable of transmitting and receiving power from the power grid. The power system B1 includes a plurality of charging devices A1 and a centralized control device F. The power system B1 may also include other power devices, such as a power generation device such as a solar power generation device and a power storage device equipped with a storage battery for storing power, both of which are not shown.

[0018] The centralized control device F manages a plurality of charging devices A1 (and other power devices). The centralized control device F performs energy management, and the total power P(t), which is the current input / output power of the entire power system B1, is set to its target value, which is the total target value P(t). c The overall target value P c The value input from the host device is set to the overall target value P cmay be set by an operation input by an operator or in accordance with a preset program. In this embodiment, the centralized control device F uses the power value detected at the connection point between the power system B1 and the power grid as the total power P(t). The centralized control device F may receive the detected values ​​of input and output power detected by each charging device A1, and use the total value calculated from these detected values ​​as the total power P(t). In the following description, when the power system B1 is receiving power from the power grid, the total power P(t) is a positive value. On the other hand, when the power system B1 is transmitting power to the power grid (reverse power flow), the total power P(t) is a negative value. In other words, the greater the charging power of the charging device A1, the greater the power value of the charging power. The centralized control device F uses the set total target value P c and the total power P(t), the centralized control device F calculates a power command value for each charging device A1 (and each other power device) based on the difference between the total power P(t) and the calculated power command value, and transmits it to the corresponding charging device A1 (or each other power device). Note that the communication method is not limited, and may be wired communication or wireless communication. A detailed description of the centralized control device F will be omitted.

[0019] Each charging device A1 is a device that charges the connected electric vehicle 2. The electric vehicle 2 is a vehicle that can run using an electric motor as a power source, and includes vehicles equipped with an internal combustion engine (for example, a plug-in hybrid vehicle). The electric vehicle 2 is equipped with a storage battery 21. The charging device A1 charges the storage battery 21 of the electric vehicle 2 connected via a charging cable 19. The electric motor of the electric vehicle 2 operates using power stored in the storage battery 21. Each charging device A1 is a so-called quick charging device, and performs quick charging by outputting DC power. Each charging device A1 controls charging power based on a received power command value. Each charging device A1 and power device controls input / output power based on the power command value received from the centralized control device F, so that the output power (total power P(t)) of the entire power system B1 reaches an overall target value P c is controlled by.

[0020] The charging device A1 includes a DC power supply unit 11, a power detection unit 12, a first communication unit 13, a second communication unit 14, a control unit 16, and a charging cable 19.

[0021] DC power supply unit 11 is configured to output DC power in response to a command from control unit 16. DC power supply unit 11 includes, for example, a converter and a smoothing circuit. The converter converts AC power input from the power grid into DC power in response to a command from control unit 16. The smoothing circuit smoothes the DC power output by the converter and outputs the DC power. Note that the specific configuration of DC power supply unit 11 is not limited as long as it can output DC power. For example, DC power supply unit 11 may include a transformer that boosts the AC voltage input from the power grid. DC power supply unit 11 outputs DC power via power line 11a.

[0022] The power detection unit 12 detects the output power of the DC power supply unit 11. The power detection unit 12 outputs the detected power detection value to the control unit 16. Note that the charging device A1 may not include the power detection unit 12, and a power sensor may be installed on the output side of the charging device A1. In this case, the power detection value detected by the power sensor may be output to the control unit 16.

[0023] The first communication unit 13 communicates with the electric vehicle 2. The first communication unit 13 communicates with the electric vehicle 2 connected to the charging cable 19 via a communication line 13a arranged in the charging cable 19. The first communication unit 13 communicates with the electric vehicle 2 according to, for example, the CAN (Controller Area Network) communication standard. Note that the communication standard is not limited. The first communication unit 13 receives information from the electric vehicle 2, such as the capacity of the storage battery 21 and the current charging rate (SoC: State of Charge). Note that the information exchanged between the first communication unit 13 and the electric vehicle 2 is not limited. Furthermore, the first communication unit 13 communicates to determine a power target value at the start of charging. Furthermore, if the electric vehicle 2 supports dynamic control, the first communication unit 13 communicates to change the power target value. Details of the communication to determine the power target value at the start of charging and the communication to change the power target value will be described later.

[0024] The charging cable 19 has a power line 11a and a communication line 13a arranged inside. The charging cable 19 is connected to the electric vehicle 2 by connecting a charging connector 191 arranged at the tip to a plug-in connector 22 of the electric vehicle 2. The electric vehicle 2 connected to the charging cable 19 has its storage battery 21 charged by power supplied from the DC power supply unit 11 via the power line 11a. The electric vehicle 2 connected to the charging cable 19 also communicates with the charging device A1 (first communication unit 13) via the communication line 13a. Note that communication between the electric vehicle 2 and the charging device A1 (first communication unit 13) may be performed wirelessly.

[0025] The second communication unit 14 communicates with the centralized control device F. The second communication unit 14 receives a power command value from the centralized control device F. Note that the information transmitted and received between the second communication unit 14 and the centralized control device F is not limited. Furthermore, the communication between the centralized control device F and the charging device A1 (second communication unit 14) may be wired communication or wireless communication. Furthermore, the communication standard is not limited.

[0026] The control unit 16 is configured to control the charging device A1 and is realized by, for example, a microcomputer. The control unit 16 controls the power output by the DC power supply unit 11. The control unit 16 also communicates with the electric vehicle 2 via the first communication unit 13 and with the centralized management device F via the second communication unit 14.

[0027] At the start of charging, the control unit 16 transmits to the electric vehicle 2 via the first communication unit 13 the power value that the charging device A1 can output (hereinafter referred to as the "capable output power value"). The available output power value is set to the power command value received from the centralized control device F via the second communication unit 14. The electric vehicle 2 transmits to the charging device A1 a power value that it desires to output (hereinafter referred to as the "desired power value") that is equal to or less than the received available output power value. Normally, at the start of charging, the power value that the electric vehicle 2 desires to output is greater than the available output power value, so the desired power value becomes the available output power value (power command value). The control unit 16 sets the desired power value received via the first communication unit 13 as the power target value. Note that the control unit 16 may first receive the desired power value from the electric vehicle 2, and then set the power target value to a power value that is equal to or less than the received power value but equal to or less than the power command value. In other words, the smaller of the desired power values ​​of both the charging device A1 and the electric vehicle 2 is set as the power target value.

[0028] The control unit 16 performs feedback control so that the output power of the DC power supply unit 11 becomes the power target value. The control unit 16 generates a drive signal so that the difference between the power detection value detected by the power detection unit 12 and the power target value becomes zero, and outputs the drive signal to the DC power supply unit 11, thereby driving the DC power supply unit 11.

[0029] If the connected electric vehicle 2 supports dynamic control, when the power command value received from the centralized control device F changes, the charging device A1 requests the electric vehicle 2 to change the charging power in real time, thereby changing the power target value. As a result, the output power of the charging device A1 (DC power supply unit 11) changes according to the power command value. On the other hand, if the connected electric vehicle 2 does not support dynamic control, even if the power command value changes, the power target value set at the start of charging cannot be changed, and therefore the output power of the charging device A1 (DC power supply unit 11) does not change. In this case, the charging device A1 ignores the power command value and is therefore unable to implement energy management. The charging device A1 performs charging processing that allows energy management to be implemented even if the connected electric vehicle 2 does not support dynamic control.

[0030] In this charging process, when a discrepancy is detected between the power detection value, which detects the output power of the charging device A1 (DC power supply unit 11), and the power command value received from the centralized control device F, charging is stopped and resumed after a predetermined suspension time. If the power command value and the power detection value differ, the control unit 16 can determine that the connected electric vehicle 2 does not support dynamic control. Furthermore, when charging is resumed, the power target value is reset based on the power command value. As a result, even if the connected electric vehicle 2 does not support dynamic control, the control unit 16 can change the power target value based on the power command value. Note that if the connected electric vehicle 2 supports dynamic control, the power command value and the power detection value do not differ, and therefore charging is not stopped. The control unit 16 has a start instruction unit 161, a discrepancy detection unit 162, a stop instruction unit 163, and an end instruction unit 164 as functional components for performing the charging process.

[0031] The start instruction unit 161 is a functional component for starting charging. When an operation signal instructing the start of charging is input by operating an operation unit (not shown) (for example, when a charging start button is pressed), and when charging is resumed by the charging process, the start instruction unit 161 causes the DC power supply unit 11 to start output. First, the start instruction unit 161 sets the power target value as described above by communicating with the electric vehicle 2 via the first communication unit 13. Then, the start instruction unit 161 causes a drive signal generation unit (not shown) to generate a drive signal and output the drive signal to the DC power supply unit 11 based on the power target value.

[0032] The deviation detection unit 162 is a functional component for detecting a deviation state in which the power detection value detected by the power detection unit 12 deviates from the power command value received from the centralized management device F. The deviation detection unit 162 detects the deviation state when a state in which a power difference ΔP (=|Pout-Pref|), which is the difference between the power detection value Pout and the power command value Pref, is equal to or greater than a first threshold value Pth1, continues for a determination time Tth or more (first condition), and the power difference ΔP becomes equal to or greater than a second threshold value Pth2 (second condition). Note that the first threshold value Pth1, the second threshold value Pth2, and the determination time Tth are not limited and are set appropriately depending on experimental or simulation results. Furthermore, the method by which the deviation detection unit 162 detects the deviation state is not limited. The deviation detection unit 162 starts detecting the deviation state when the start instruction unit 161 starts charging.

[0033] The stop instruction unit 163 is a functional configuration for stopping charging. When the deviation detection unit 162 detects a deviation state, the stop instruction unit 163 causes the DC power supply unit 11 to stop output. Specifically, the stop instruction unit 163 causes the drive signal generation unit to stop generating the drive signal or the drive signal to the DC power supply unit 11 to stop outputting the drive signal. The stop instruction unit 163 causes the start instruction unit 161 to resume charging after a predetermined stop time Tstop has elapsed since the charging was stopped. Note that the stop instruction unit 163 may also cause the start instruction unit 161 to resume charging immediately after the charging was stopped. In other words, the stop time Tstop may be "0".

[0034] The termination instruction unit 164 is a functional configuration for terminating charging. The termination instruction unit 164 causes the DC power supply unit 11 to stop output when an operation signal instructing termination of charging is input by operating an operation unit (not shown) (for example, when a charging termination button or an emergency stop button is pressed) or when a signal indicating termination of charging is input from the electric vehicle 2. When the termination instruction unit 164 terminates charging, charging is not resumed, unlike when the stop instruction unit 163 stops charging.

[0035] 2 is an example of a flowchart illustrating the charging process performed by the control unit 16. The charging process is executed when the electric vehicle 2 is connected to the charging cable 19 and a command to start charging is issued.

[0036] First, pre-charging processing is executed (S1). Specifically, the start instruction unit 161 sets a power target value by communicating with the electric vehicle 2 via the first communication unit 13. Next, charging is started (S2). Specifically, the start instruction unit 161 generates a drive signal based on the power target value and outputs it to the DC power supply unit 11.

[0037] Next, a power difference ΔP is detected (S3). Specifically, the deviation detection unit 162 calculates the power difference ΔP, which is the difference between the power detection value Pout input from the power detection unit 12 and the power command value Pref received from the centralized management device F. Next, it is determined whether or not an instruction to end the charging has been given (S4). Specifically, the end instruction unit 164 determines whether or not an operation signal instructing the end of charging has been input. If an instruction to end the charging has been given (S4: YES), charging is stopped (S5), and the charging process is ended.

[0038] On the other hand, if charging has not been completed (S4: NO), it is determined whether the power difference ΔP is equal to or greater than the first threshold value Pth1 (S6). If the power difference ΔP is less than the first threshold value Pth1 (S6: NO), the process returns to step S3. On the other hand, if the power difference ΔP is equal to or greater than the first threshold value Pth1 (S6: YES), it is determined whether the measured time since the power difference ΔP became equal to or greater than the first threshold value Pth1 has passed a determination time Tth (S7). If the determination time Tth has passed (S7: YES), it is determined that the first condition is satisfied, and the process proceeds to step S8. On the other hand, if the determination time Tth has not passed (S7: NO), the process returns to step S3.

[0039] In step S8, it is determined whether the power difference ΔP is equal to or greater than the second threshold value Pth2 (S8). If the power difference ΔP is less than the second threshold value Pth2 (S8: NO), the process returns to step S3. On the other hand, if the power difference ΔP is equal to or greater than the second threshold value Pth2 (S8: YES), the second condition is also satisfied, and it is determined that a deviation state exists, and charging is stopped (S9).

[0040] Next, it is determined whether the time counted since charging was stopped has passed the stop time Tstop (S10). If the stop time Tstop has not passed (S10: NO), the process returns to step S10, and the determination of step S10 is repeated. On the other hand, if the stop time Tstop has passed (S10: YES), the process returns to step S1, and pre-charging processing is executed (S1), and charging is resumed (S2). Note that the processing shown in the flowchart of FIG. 2 is an example, and the charging processing performed by control unit 16 is not limited to the above.

[0041] 3A, 3B, and 3C are time charts illustrating the change over time in the detected power value Pout due to the charging process performed by the control unit 16 of the charging device A1. In each diagram in FIG. 3, the solid line indicates the change over time in the detected power value Pout, and the dashed line indicates the power command value Pref. In FIGS. 3A, 3B, and 3C, the charging device A1 starts charging from time t0, and the power command value Pref decreases as the total power P(t) increases.

[0042] Fig. 3(a) shows the change over time of the detected power value Pout when the connected electric vehicle 2 supports dynamic control. As shown in Fig. 3(a), the detected power value Pout changes in accordance with the power command value Pref.

[0043] 3(b) shows the change over time of the detected power value Pout when the connected electric vehicle 2 does not support dynamic control and the control unit 16 does not perform the charging process according to this embodiment. As shown in FIG. 3(b), the detected power value Pout remains constant after matching the power command value Pref and does not change even when the power command value Pref decreases. In this case, energy management cannot be implemented.

[0044] FIG. 3(c) shows the change over time in the detected power value Pout when the connected electric vehicle 2 does not support dynamic control and the control unit 16 is performing the charging process according to this embodiment. As shown in FIG. 3(c), the detected power value Pout remains constant after matching the power command value Pref and does not change even when the power command value Pref decreases. At time t1, the power difference ΔP (=|Pout-Pref|) is equal to or greater than the first threshold value Pth1. Then, this state continues for a determination time Tth or more (first condition), and the power difference ΔP becomes equal to or greater than the second threshold value Pth2 (second condition), and a deviation state is detected at time t2. As a result, charging is stopped at time t2, and the detected power value Pout becomes "0." Thereafter, at time t3, after the stop time Tstop has elapsed, charging is resumed. The detected power value Pout matches the power command value Pref when charging is resumed. In this way, in the charging process according to this embodiment, charging is stopped when a deviation state is detected, and then charging is resumed, so that the power target value can be changed based on the power command value Pref even if the connected electric vehicle 2 does not support dynamic control. Therefore, the charging device A1 can perform energy management.

[0045] FIG. 3(d) shows the change in the detected power value Pout over time when the connected electric vehicle 2 does not support dynamic control and the control unit 16 is performing the charging process according to this embodiment, illustrating the case where the power command value Pref increases. As shown in FIG. 3(d), the detected power value Pout remains constant after matching the power command value Pref and does not change even as the power command value Pref increases. At time t1, the power difference ΔP (=|Pout-Pref|) is equal to or greater than the first threshold value Pth1. Then, this state continues for a determination time Tth or more (first condition), and the power difference ΔP becomes equal to or greater than the second threshold value Pth2 (second condition), and a deviation state is detected at time t2. As a result, charging is stopped at time t2, and the detected power value Pout becomes "0." Thereafter, at time t3, after the stop time Tstop has elapsed, charging is resumed. The detected power value Pout matches the power command value Pref when charging resumes. In this way, in the charging process according to this embodiment, even when the power command value Pref increases, the power target value can be changed based on the power command value Pref, so that the charging device A1 can perform energy management.

[0046] FIG. 4 shows the results of a simulation when an electric vehicle 2 that does not support dynamic control is connected to the charging device A1. FIG. 4(a) shows the change over time in the power command value Pref. FIG. 4(b) shows the change over time in the detected power value Pout. In each figure, the horizontal axis represents time [seconds], and the vertical axis represents each power value [kW]. In this simulation, the first threshold value Pth1 and the second threshold value Pth2 are set to 20 kW, and the determination time Tth and stop time Tstop are set to 60 seconds.

[0047] Charging began at 120 seconds with the power command value Pref set to 50 kW. As shown in Figure 4(b), the detected power value Pout increased and matched the power command value Pref (50 kW). After that, the power command value Pref decreased, but the detected power value Pout remained constant. At 220 seconds, the power difference ΔP between the detected power value Pout and the power command value Pref reached 20 kW. The power command value Pref then remained constant. At 280 seconds, 60 seconds after the power difference ΔP reached 20 kW, a discrepancy was detected and charging was stopped, causing the detected power value Pout to return to "0." At 340 seconds, 60 seconds after charging was stopped, charging resumed, and the detected power value Pout matched the power command value Pref (30 kW) at the time charging resumed. Note that this simulation simulates a state in which the power command value Pref is suppressed, and does not cover an increase in the power command value Pref.

[0048] Next, the operation and effects of the charging device A1 and the power system B1 according to this embodiment will be described.

[0049] According to this embodiment, the deviation detection unit 162 detects a deviation state based on the power difference ΔP, which is the difference between the power detection value Pout and the power command value Pref. When the deviation detection unit 162 detects a deviation state, the stop instruction unit 163 causes the DC power supply unit 11 to stop output. The start instruction unit 161 causes the DC power supply unit 11 to resume output after a predetermined stop time Tstop has elapsed since charging was stopped. When charging is resumed, the power target value is reset based on the power command value Pref. As a result, the charging device A1 can change the power target value based on the power command value Pref even when an electric vehicle 2 that does not support dynamic control is connected, thereby enabling energy management.

[0050] Furthermore, according to this embodiment, the deviation detection unit 162 detects a deviation state when a state in which the power difference ΔP (=|Pout-Pref|), which is the difference between the power detection value Pout and the power command value Pref, is equal to or greater than a first threshold value Pth1 continues for a determination time Tth or more (first condition) and the power difference ΔP becomes equal to or greater than a second threshold value Pth2 (second condition). This allows the deviation detection unit 162 to accurately detect a deviation state.

[0051] In the present embodiment, when the start instruction unit 161 resumes charging after the stop instruction unit 163 stops charging, the target power value is set based on the power command value received from the centralized control device F. However, this is not limited to this. The control unit 16 may store the power command value received from the centralized control device F when the stop instruction unit 163 stops charging, and the start instruction unit 161 may set the target power value based on the stored power command value (i.e., the power command value when charging was stopped) when resuming charging. If the centralized control device F reduces the power command value to suppress charging, causing the charging device A1 to enter a deviation state and stop charging, the total power P(t), which is the input / output power of the entire power system B1, will decrease more than necessary. In this case, the centralized control device F increases the power command value output to each charging device A1 (power device) in order to increase the total power P(t). Therefore, if the start instruction unit 161 of the charging device A1 that stopped charging sets a target power value based on the currently increased power command value and resumes charging, the total power P(t) becomes larger than necessary, and the centralized control device F must suppress charging. In this way, the centralized control device F repeatedly increases and decreases the power command value. When the start instruction unit 161 resumes charging, it sets the target power value based on the power command value when charging was stopped, thereby suppressing the repeated increase and decrease of the power command value by the centralized control device F described above.

[0052] In the present embodiment, the deviation detection unit 162 detects a deviation state when the first and second conditions are satisfied. However, this is not limiting. As shown in FIG. 5(a), the deviation detection unit 162 may detect a deviation state when the first condition is satisfied, i.e., when the state in which the power difference ΔP (=|Pout-Pref|) is equal to or greater than the first threshold Pth1 has continued for a determination time Tth or longer. As shown in FIG. 5(b), the deviation detection unit 162 may detect a deviation state when the second condition is satisfied, i.e., when the power difference ΔP is equal to or greater than the second threshold Pth2. The deviation detection unit 162 may also detect a deviation state when the first or second condition is satisfied. As shown in FIG. 5(c), the deviation detection unit 162 may calculate a power difference W by integrating the power difference ΔP over time, and detect a deviation state when the calculated power difference W is equal to or greater than a threshold Wth. Even in these cases, the deviation detection unit 162 can detect the deviation state.

[0053] Furthermore, in this embodiment, the case where the charging device A1 charges the electric vehicle 2 has been described, but this is not limiting. The charging device A1 may charge a moving body other than the electric vehicle 2. Other examples of the moving body include other vehicles such as two-wheeled vehicles (electric motorcycles, power-assisted bicycles), ships, and airplanes, as well as unmanned moving bodies such as automated guided vehicles and drones.

[0054] Second Embodiment Fig. 6 is a block diagram showing the overall configuration of a power system B2 equipped with a charging device A2 according to a second embodiment. In Fig. 6, elements that are the same as or similar to those in the first embodiment are given the same reference numerals as those in the first embodiment. The power system B2 according to this embodiment differs from the power system B1 according to the first embodiment in that a centralized control device F transmits a common induction index pr to each charging device A2 (and each of the other power devices), and each charging device A2 calculates a power command value Pref.

[0055] In the power system B2 according to this embodiment, the total power P(t) is equal to the total target value P cThe centralized control device F according to this embodiment does not calculate a power command value Pref for each charging device A2 (and each of the other power devices), but controls the total power P(t) to the overall target value P c The centralized control device F calculates the common induction index pr for controlling the total power P(t) and the total target value P c Based on the difference between the above and the common guide index pr, the centralized control device F calculates the guide index pr. Then, the centralized control device F transmits a common guide index pr to each charging device A2 (and each of the other power devices). In this embodiment, the centralized control device F transmits the guide index pr to each charging device A2 (and each of the other power devices) by wireless simultaneous transmission. The communication method is not limited, and may be wired communication or wireless communication. Based on the common guide index pr received from the centralized control device F, each charging device A2 (and each of the other power devices) autonomously controls the input / output power. As a result, the output power (total power P(t)) of the entire power system B2 reaches the overall target value P c is controlled by.

[0056] The control unit 16 of each charging device A2 (and each of the other power devices) further includes a command value calculation unit 166. The command value calculation unit 166 calculates a power command value Pref based on an optimization problem using the guide index pr received by the second communication unit 14 from the centralized control device F. That is, in this embodiment, instead of the centralized control device F calculating the power command value Pref for each of the multiple charging devices A2 (and each of the other power devices), each of the charging devices A2 (and each of the other power devices) calculates the power command value Pref using the guide index pr.

[0057] In this embodiment, too, the deviation detection unit 162 detects a deviation state based on the power difference ΔP, which is the difference between the power detection value Pout and the power command value Pref. When the deviation detection unit 162 detects a deviation state, the stop instruction unit 163 causes the DC power supply unit 11 to stop output. The start instruction unit 161 causes the DC power supply unit 11 to resume output after a predetermined stop time Tstop has elapsed since charging was stopped. When charging is resumed, the power target value is reset based on the power command value Pref. This allows the charging device A2 to change the power target value based on the power command value Pref even when an electric vehicle 2 that does not support dynamic control is connected, thereby enabling energy management. Furthermore, the charging device A2 has a common configuration with the charging device A1 and thus achieves the same effects as the charging device A1. Furthermore, according to this embodiment, the centralized control device F simply calculates and transmits a common guidance index pr without understanding the status of each power device, thereby reducing the burden of calculations and communication. Therefore, a high-performance and expensive centralized control device is not required, and the initial installation cost can be reduced. Furthermore, when the power system B2 is expanded, the centralized control device F does not need to be significantly modified.

[0058] The charging device and power system according to the present invention are not limited to the above-described embodiment, and the specific configurations of the components of the charging device and power system according to the present invention can be freely designed and modified in various ways. [Explanation of symbols]

[0059] A1, A2: charging device, 11: DC power supply unit, 16: control unit, 161: start instruction unit, 162: deviation detection unit, 163: stop instruction unit, 2: electric vehicle, 21: storage battery F: Centralized control device, B1, B2: Power system

Claims

1. A charging device that charges a storage battery of an electric vehicle that moves by driving an electric motor with power from the storage battery, a DC power supply unit that outputs DC power; a control unit that controls the DC power supply unit; Equipped with The control unit a deviation detection unit that detects a deviation state in which a power detection value obtained by detecting an output power of the DC power supply unit deviates from a set power command value; a stop instruction unit that causes the DC power supply unit to stop output when the deviation detection unit detects the deviation state; a start instruction unit that causes the DC power supply unit to start output after a stop time has elapsed since the output was stopped by the stop instruction unit; and Equipped with Charging device.

2. the deviation detection unit detects the deviation state when a state in which a power difference between the detected power value and the power command value is equal to or greater than a first threshold value has continued for a determination time or longer. The charging device according to claim 1 .

3. the deviation detection unit detects the deviation state when a power difference between the detected power value and the power command value becomes equal to or greater than a second threshold value.

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

4. the control unit stores a power command value when the stop instruction unit stops the output of the DC power supply unit, and uses the stored power command value when the start instruction unit starts the output of the DC power supply unit after the stop time has elapsed. The charging device according to claim 1 .

5. The charging device according to claim 1; a centralized control device that controls a plurality of power devices including the charging device, the centralized management device calculates a guide index for controlling an overall power, which is a current input / output power of the entire power system, to an overall target value, and transmits the guide index common to the plurality of power devices; the control unit of the charging device calculates the power command value based on an optimization problem using the received guidance index. Power system.

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