Charging control device

Abstract

To provide a charging control device capable of suppressing a flicker phenomenon even when a plurality of chargers is mounted on a vehicle.SOLUTION: A charging control device 1 includes an ECU 6. When the number of a plurality of chargers in operation is decreased according to power from an inlet 2, the ECU 6 increases charging power of at least one predetermined charger of the plurality of chargers and decreases the charging power of at least one other charger with time, and when the charging power of the other charger becomes smaller than a predetermined value, stops the other charger.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a charging control device.

Background Art

[0002] Patent Document 1 describes a technique for determining the charging power of a power storage device mounted on a vehicle according to the output current of a charger and the required power of the vehicle. In this technique, the charger is controlled so that power is supplied from a commercial power supply to the vehicle with a power command value that changes stepwise with a change amount smaller than a predetermined power change amount toward the vehicle required power, thereby suppressing the occurrence of a flicker phenomenon in the commercial power supply.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, only one charger provided in the vehicle is assumed, and no case where a plurality of chargers are mounted on the vehicle is assumed at all. There has been a need for a technique for suppressing the flicker phenomenon in the case where a plurality of chargers are mounted on the vehicle.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a charging control device capable of suppressing a flicker phenomenon even when a plurality of chargers are mounted on a vehicle.

Means for Solving the Problems

[0006] To solve the above-mentioned problems and achieve the objective, the charging control device according to the present disclosure is a charging control device for controlling the charging of a vehicle, comprising a processor that controls the charging power from an inlet to a plurality of chargers, wherein when the number of operating chargers of the plurality of chargers is reduced in accordance with the power from the inlet, the processor increases the charging power of at least one predetermined charger of the plurality of chargers, while decreasing the charging power of at least one other charger over time, and stops the other charger when the charging power of the other charger falls below a predetermined value. [Effects of the Invention]

[0007] According to this disclosure, even when a vehicle is equipped with multiple chargers, the flicker phenomenon can be suppressed. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing the functional configuration of the charging control device according to Embodiment 1. [Figure 2] Figure 2 shows the relationship between the charging power command output by the ECU of the charging control device according to Embodiment 1 and time. [Figure 3] Figure 3 is a diagram showing the relationship between the charging power and time of the first charger and the second charger, respectively, provided in the charging control device according to Embodiment 1. [Figure 4] Figure 4 shows the relationship between the charging power command output by the ECU of the charging control device according to Embodiment 1 and time. [Figure 5] Figure 5 shows the relationship between the charging power and time of the first charger and the second charger, respectively, provided in the charging control device according to Embodiment 2. [Figure 6] Figure 6 is a schematic diagram showing the functional configuration of the charging control device according to Embodiment 3. [Figure 7] Figure 7 shows the relationship between the charging power and time of the first charger and the second charger, respectively, provided by the power distribution unit of the charging control device according to Embodiment 3. [Figure 8] Figure 8 shows the relationship between the charging power and time of the first charger and the second charger, respectively, provided by the power distribution unit of the charging control device according to Embodiment 4. [Modes for carrying out the invention]

[0009] Hereinafter, a vehicle equipped with a charging control device according to an embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that are easily substituted or substantially identical to those that are replaceable by a person skilled in the art. Furthermore, the figures referenced in the following description only schematically show the shape, size, and positional relationships to the extent that the contents of the present disclosure can be understood. In other words, the present disclosure is not limited to the shapes, sizes, and positional relationships exemplified in the figures.

[0010] (Embodiment 1) [Configuration of the charging control device] Figure 1 is a schematic diagram showing the functional configuration of a charging control device according to Embodiment 1. The charging control device 1 shown in Figure 1 is installed in vehicles such as HEVs (Hybrid Electric Vehicles), PHEVs (Plug-in Hybrid Electric Vehicles), and BEVs (Battery Electric Vehicles).

[0011] As shown in Figure 1, the charging control device 1 comprises an inlet 2, a first charger 3, a second charger 4, a battery 5, and an ECU (Electronic Control Unit) 6. In Embodiment 1, the case in which the charging control device 1 is equipped with two chargers, the first charger 3 and the second charger 4, is described, but the invention is not limited to this case and can be applied even if there are multiple chargers, for example, three or more.

[0012] Inlet 2 is electrically connected to the first charger 3 and the second charger 4, which are arranged in parallel. Inlet 2 is electrically connected to an external commercial power source, such as a charging station, via a cable (not shown), and outputs charging power supplied from the commercial power source to either the first charger 3 or the second charger 4.

[0013] Each of the first charger 3 and the second charger 4 is electrically connected to the inlet 2 and the battery 5. Under the control of the ECU 6, each of the first charger 3 and the second charger 4 converts the AC power from the inlet 2 into DC power and outputs it to the battery 5. Also, under the control of the ECU 6, each of the first charger 3 and the second charger 4 converts the DC power output from the battery 5 into a predetermined voltage and outputs it to a motor generator (not shown) or an AC 100V outlet. Furthermore, each of the first charger 3 and the second charger 4 controls the charging power output to the battery 5 according to the charging power command instructed by the ECU 6. Note that each of the first charger 3 and the second charger 4 can slowly change the charging power over a certain period of time even if the charging power command is steep due to stability or performance constraints. Here, a steep charging power command refers to a state caused by the on / off switching of a pulse-like signal. Also, slowly changing the charging power over a certain period of time refers to a straight line or curve that changes over time. In the following, when referring to both the first charger 3 and the second charger 4, the term "charger" will be used.

[0014] The battery 5 is constructed using, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. The battery 5 is electrically connected to the first charger 3 and the second charger 4. Under the control of the ECU 6, the battery 5 outputs charging power to the first charger 3 and the second charger 4.

[0015] The ECU6 is implemented using a processor with memory and hardware. This hardware includes, for example, memory, a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and an FPGA (Field-Programmable Gate Array). The ECU6 calculates the charging power of the first charger 3 and the second charger 4 from the power used to charge the battery 5, and based on this calculation, outputs charging power commands to instruct the first charger 3 and the second charger 4 to start charging, stop charging, and set the charging power. For example, the ECU6 calculates the total charging power to charge the battery 5 based on the State of Charge (SOC) of the battery 5, and outputs corresponding charging power commands to the first charger 3 and the second charger 4 based on this calculated total charging power. Furthermore, the ECU 6 outputs stop information to at least one of the first charger 3 and the second charger 4 to stop outputting charging power, and operating unit switching information to instruct the switching of the number of operating chargers. In Embodiment 1, the ECU 6 functions as a processor.

[0016] [Processing to switch the number of chargers in operation] Next, the switching process when the ECU 6 switches the number of operating chargers will be described. FIG. 2 is a diagram showing the relationship between the charging power command output by the ECU 6 and time. FIG. 3 is a diagram showing the relationship between the charging power of each of the first charger 3 and the second charger 4 and time. In FIG. 2, the horizontal axis represents time, and the vertical axis represents the charging power command output by the ECU 6 to each of the first charger 3 and the second charger 4. Also, in FIG. 3, the horizontal axis represents time, and the vertical axis represents the charging power. Further, in FIG. 2, the broken line L1 shows the change over time of the first charging power command to the first charger 3 by the ECU 6, and the broken line L2 shows the change over time of the second charging power command to the second charger 4 by the ECU 6. Furthermore, in FIG. 3, the broken line L11 shows the total charging power obtained by adding together the charging power of the first charger 3 and the charging power of the second charger 4, the broken line L12 shows the charging power of the first charger 3, and the broken line L13 shows the charging power of the second charger 4.

[0017] First, as shown by the broken line L1 and the broken line L2 in FIG. 2, the case of stopping the operation of the second charger 4 when each of the first charger 3 and the second charger 4 is outputting charging power will be described. At this time, the ECU 6 gradually decreases the second charging power command and outputs it to the second charger 4. When the charging power of the second charger 4 becomes smaller than a predetermined value, the ECU 6 stops the second charging power command (at time t1) and outputs stop information to the second charger 4. Further, the ECU 6 outputs the first charging power command and the operation number switching information to the first charger 3 so that the charging power output by the first charger 3 becomes the charging power obtained by adding the charging power corresponding to the decrease amount of the charging power output by the second charger 4.

[0018] As shown by the broken lines L11 to L13 in FIG. 3, the second charger 4 gradually reduces the charging power from the operation stop time t1 in accordance with the second charging power command. On the other hand, as shown by the broken lines L11 and L12 in FIG. 3, the first charger 3 gradually increases the charging power so that the total charging power output to the battery 5 by each of the first charger 3 and the second charger 4 immediately before the operation stop time t1 (refer to the broken line L11) becomes the charging power output to the battery 5 (refer to the broken line L12).

[0019] Thereafter, as shown by the broken line L1 in FIG. 2, the ECU 6 gradually reduces the first charging power command and outputs it to the first charger 3. In this case, as shown by the broken line L12 in FIG. 3, the first charger 3 gradually reduces the charging power and outputs it to the battery 5. Thereby, when switching the number of operating chargers, it is possible to prevent the total charging power of the first charger 3 and the second charger 4 from changing suddenly, so that the flicker phenomenon can be suppressed.

[0020] Further, when the ECU 6 completely stops each of the first charger 3 and the second charger 4, the first charging power command and the second charging power command are each stopped. In this case, each of the first charger 3 and the second charger 4 rapidly reduces the charging power. Thereby, the safety during charging can be ensured.

[0021] According to the first embodiment described above, the ECU 6 gradually decreases and outputs the second charging power command to the second charger 4, stops the second charging power command at the operation stop time t1, and outputs the first charging power command to the first charger 3 so that the charging power output by the first charger 3 becomes the charging power obtained by adding the amount of decrease in the charging power output by the second charger 4. Thereby, when switching the number of operating chargers, it is possible to prevent the total charging power of the first charger 3 and the second charger 4 from changing suddenly, so that the flicker phenomenon can be suppressed.

[0022] Furthermore, when the ECU 6 completely stops the first charger 3 and the second charger 4, it stops the first charging power command and the second charging power command, causing the charging power of the first charger 3 and the second charger 4 to decrease rapidly, thereby ensuring safety during charging.

[0023] (Embodiment 2) Next, Embodiment 2 will be described. The charging control device according to Embodiment 2 has the same configuration as the charging control device 1 according to Embodiment 1, with only the processing it performs being different. In the following, the actions performed by the charging control device according to Embodiment 2 will be described. Note that components identical to those in the charging control device 1 according to Embodiment 1 are denoted by the same reference numerals, and detailed descriptions are omitted.

[0024] [Processing to switch the number of chargers in operation] Figure 4 shows the relationship between the charging power command output by the ECU 6 and time. Figure 5 shows the relationship between the charging power of the first charger 3 and the second charger 4 and time. In Figure 4, the horizontal axis represents time, and the vertical axis represents the charging power command output by the ECU 6 to the first charger 3 and the second charger 4, respectively. In Figure 5, the horizontal axis represents time, and the vertical axis represents charging power. Furthermore, in Figure 4, line L21 shows the time change of the first charging power command from the ECU 6 to the first charger 3, and line L22 shows the time change of the second charging power command from the ECU 6 to the second charger 4. Furthermore, in Figure 5, line L31 shows the total charging power, which is the sum of the charging power of the first charger 3 and the charging power of the second charger 4, line L32 shows the charging power of the first charger 3, and line L33 shows the charging power of the second charger 4.

[0025] First, as shown by the broken lines L21 and L22 in Figure 4, we will explain the case when the operation of the second charger 4 is stopped when both the first charger 3 and the second charger 4 are outputting charging power. At this time, from time t2, when the ECU 6 determines that the second charger 4 should be stopped, it outputs a first charging power command to the first charger 3 in stages, while simultaneously outputting a second charging power command to the second charger 4 in stages. Specifically, the ECU 6 outputs the first charging power command to the first charger 3 in stages, increasing the charging power so that the total charging power is the sum of the charging power output by the first charger 3 and the charging power output by the second charger 4, by adding the amount of decrease in charging power output by the second charger 4.

[0026] As shown by the broken lines L31 to L33 in Figure 5, the second charger 4 gradually reduces its charging power in stages from time t3, which corresponds to time t2, when the ECU 6 determines to stop the second charger 4 in accordance with the second charging power command. In contrast, as shown by the broken lines L31 and L32 in Figure 5, the first charger 3 gradually increases its charging power in stages from time t3, which corresponds to time t2, when the ECU 6 determines to stop the second charger 4 in accordance with the first charging power command, so that the total charging power that each of the first charger 3 and the second charger 4 will charge to the battery 5 (see broken line L31), and outputs it to the battery 5.

[0027] Subsequently, as shown by the broken line L21 in Figure 4, the ECU 6 gradually reduces the first charging power command and outputs it to the first charger 3. In this case, as shown by the broken line L32 in Figure 5, the first charger 3 gradually reduces the charging power and outputs it to the battery 5. This prevents a sudden change in the total charging power of the first charger 3 and the second charger 4 when switching the number of operating chargers, thereby suppressing the flicker phenomenon.

[0028] Furthermore, when the ECU 6 completely shuts down the first charger 3 and the second charger 4, it also shuts down the first and second charging power commands. In this case, the first charger 3 and the second charger 4 rapidly reduce their charging power. This ensures safety during charging.

[0029] According to the embodiment 2 described above, from time t2 when the ECU 6 determines to stop the second charger 4, the first charging power command to the first charger 3 is output in stages, while the second charging power command to the second charger 4 is output in stages, while the second charging power command is output in stages. This prevents a sudden change in the total charging power of the first charger 3 and the second charger 4 when switching the number of operating chargers, thereby suppressing the flicker phenomenon.

[0030] (Embodiment 3) Next, Embodiment 3 will be described. The charging control device according to Embodiment 3 differs in configuration from the charging control device 1 according to Embodiments 1 and 2. In the following, the configuration of the charging control device according to Embodiment 3 will be described, followed by a description of the processes performed by the charging control device according to Embodiment 3. Note that components identical to those in the charging control device 1 according to Embodiments 1 and 2 are denoted by the same reference numerals, and detailed descriptions are omitted.

[0031] [Configuration of the charging control device] Figure 6 is a schematic diagram showing the functional configuration of the charging control device according to Embodiment 3. The charging control device 1A shown in Figure 6 further includes a power distribution unit 7 in addition to the functional configuration of the charging control device 1 according to Embodiment 1. Furthermore, the charging control device 1A further includes an ECU 6A in place of the ECU 6 of the charging control device 1 according to Embodiment 1.

[0032] The power distribution unit 7 is implemented using memory and a processor with hardware. This hardware includes, for example, memory, a CPU, a DSP, and an FPGA. The power distribution unit 7 controls the first charger 3 and the second charger 4 under the control of the ECU 6A. Specifically, the power distribution unit 7 controls the first charger 3 and the second charger 4 so that the total charging power input from the inlet 2 conforms to the charging power command from the ECU 6A. More specifically, the power distribution unit 7 compares the charging power corresponding to the charging power command from the ECU 6A with a preset threshold indicating the switching of the number of operating units. If the charging power corresponding to the charging power command falls below the preset threshold indicating the switching of the number of operating units, it stops the operation of chargers that do not need to operate, such as the second charger 4. In this case, the power distribution unit 7 controls the first charger 3 and the second charger 4 so that the charging power of the second charger 4 is gradually reduced over time, while the charging power of the first charger 3 is gradually increased over time. Subsequently, the power distribution unit 7 stops the second charger 4 when the charging power supplied by the second charger 4 has decreased sufficiently.

[0033] ECU6A is implemented using a processor with memory and hardware. This hardware includes, for example, memory, a CPU, a DSP, and an FPGA. When ECU6A stops charging either the first charger 3 or the second charger 4, it outputs a charging power command to the power distribution unit 7 so that the charging power of either the first charger 3 or the second charger 4 decreases in stages.

[0034] [Processing to switch the number of chargers in operation] Next, the process by which the power distribution unit 7 switches the number of operating chargers under the control of the ECU 6A will be explained. Figure 7 is a diagram showing the relationship between the charging power of the first charger 3 and the second charger 4 and time, as determined by the power distribution unit 7. In Figure 7, the horizontal axis represents time, and the vertical axis represents charging power. Also in Figure 7, line L41 shows the total charging power, which is the sum of the charging power output by the first charger 3 and the charging power output by the second charger 4, line L42 shows the charging power output by the first charger 3, and line L43 shows the charging power output by the second charger 4.

[0035] As shown in Figure 7, the power distribution unit 7 controls the first charger 3 and the second charger 4 respectively so that the total charging power input from the inlet 2 conforms to the charging power command from the ECU 6A. Specifically, the power distribution unit 7 compares the charging power corresponding to the charging power command from the ECU 6A with a preset threshold LT1 that indicates the switching of the number of operating units. As shown by the line L41 in Figure 7, if the charging power corresponding to the charging power command from the ECU 6A falls below the threshold LT1 (time t40), the power distribution unit 7 stops the operation of chargers that do not need to operate, such as the second charger 4. In this case, as shown by the lines L42 and L43, the power distribution unit 7 controls the first charger 3 and the second charger 4 so as to gradually decrease the charging power of the second charger 4 over time (see line L43) while gradually increasing the charging power of the first charger 3 over time (see line L42). In other words, the power distribution unit 7 controls the first charger 3 and the second charger 4 respectively so that the total charging power decreases while synchronizing the decrease in the charging power of the second charger 4 with the increase in the charging power of the first charger 3. In this case, the power distribution unit 7 controls the first charger 3 and the second charger 4 respectively so that the total charging power decreases while synchronizing the decrease in the charging power of the second charger 4 with the increase in the charging power of the first charger 3 in steps smaller than the increase / decrease steps of Embodiment 2. Then, when the charging power that the second charger 4 is charging has decreased sufficiently (time t41), the power distribution unit 7 stops the second charger 4. As a result, even when the charging power of the second charger 4 is rapidly reduced, the charging control device 1A can suppress the impact on the flicker phenomenon by reducing the amount of rapid change in charging power.

[0036] According to Embodiment 3 described above, when charging is stopped for either the first charger 3 or the second charger 4, the ECU 6A outputs a charging power command to the power distribution unit 7 so that the charging power of either the first charger 3 or the second charger 4 decreases in stages. When the power distribution unit 7 stops the operation of the second charger 4, it controls the first charger 3 and the second charger 4 so that the charging power of the second charger 4 decreases gradually over time while the charging power of the first charger 3 gradually increases over time. As a result, even when the charging control device 1A rapidly decreases the charging power of the second charger 4, the amount of abrupt change in charging power is reduced, thereby suppressing the impact on the flicker phenomenon.

[0037] (Embodiment 4) Next, Embodiment 4 will be described. The charging control device according to Embodiment 4 has the same configuration as the charging control device 1A according to Embodiment 3, with only the processing it performs being different. In the following, the actions performed by the charging control device according to Embodiment 4 will be described. Note that components identical to those in the charging control device 1A according to Embodiment 3 are denoted by the same reference numerals, and detailed descriptions are omitted.

[0038] [Processing to switch the number of chargers in operation] Figure 8 shows the relationship between the charging power of the first charger 3 and the second charger 4, respectively, and time, as measured by the power distribution unit 7. In Figure 8, the horizontal axis represents time, and the vertical axis represents charging power. In Figure 8, line L51 shows the total charging power, which is the sum of the charging power output by the first charger 3 and the charging power output by the second charger 4, line L52 shows the charging power output by the first charger 3, and line L53 shows the charging power output by the second charger 4. Furthermore, in Figure 8, the threshold LT2 indicating the switching of the number of operating units is set to a lower value than the threshold LT1 in Embodiment 3 (LT1 > LT2).

[0039] As shown in Figure 8, the power distribution unit 7 controls the first charger 3 and the second charger 4 so that the total charging power input from the inlet 2 conforms to the charging power command from the ECU 6A. Specifically, the power distribution unit 7 compares the charging power corresponding to the charging power command from the ECU 6A with a preset threshold LT2 that indicates the switching of the number of operating units. As shown by the line break L51 and region Q1 in Figure 8, when the charging power corresponding to the charging power command from the ECU 6A falls below the threshold LT2 (time t5), the power distribution unit 7 stops the operation of chargers that do not need to operate, such as the second charger 4. In this case, as shown by the line breaks L52 and L53, the power distribution unit 7 controls the first charger 3 and the second charger 4 so that the charging power of the first charger 3 increases at the time the second charger 4 is stopped (time t5) (see line break L52), while gradually decreasing the charging power of each of the first charger 3 and the second charger 4 over time (see line breaks L52 and L53). In this case, the threshold LT2 indicating the switching of the number of operating units is set to a lower value than the threshold LT1 in Embodiment 3. As a result, even when the charging control device 1A rapidly reduces the charging power of the second charger 4, the amount of rapid change in charging power is reduced, thereby suppressing the impact on the flicker phenomenon.

[0040] According to Embodiment 4 described above, when charging is stopped for either the first charger 3 or the second charger 4, the ECU 6A outputs a charging power command to the power distribution unit 7 so that the charging power of either the first charger 3 or the second charger 4 decreases in stages. When the power distribution unit 7 stops the operation of the second charger 4, it controls the first charger 3 and the second charger 4 so as to gradually decrease the charging power of each of the first charger 3 and the second charger 4 over time, while increasing the charging power of the first charger 3 at the time the second charger 4 is stopped (time t5) (see line break L52). As a result, even when the charging control device 1A rapidly decreases the charging power of the second charger 4, the amount of abrupt change in charging power is reduced, thereby suppressing the impact on the flicker phenomenon.

[0041] Further effects and modifications can be readily derived by those skilled in the art. Broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents.

[0042] Although some embodiments of this application have been described in detail above with reference to the drawings, these are illustrative examples, and the present invention can be implemented in various other forms with modifications and improvements based on the knowledge of those skilled in the art, starting with the embodiments described in the disclosure section of the present invention. [Explanation of Symbols]

[0043] 1. Charging control device 2 Inlets 3. First charger 4. Second charger 5 batteries 6.6A ECU 7 Power distribution section

Claims

1. A charging control device for controlling the charging of a vehicle, It features a processor that controls the charging power from the inlet to multiple chargers, The aforementioned processor, When reducing the number of operating chargers according to the power from the inlet, the charging power of at least one predetermined charger of the plurality of chargers is increased, and the charging power of at least one other charger is decreased over time, and when the charging power of the other charger falls below a predetermined value, the other charger is stopped. Charging control device.

2. A charging control device according to claim 1, The aforementioned processor, Determine whether to reduce the number of operating chargers or to stop all of the operating chargers. If it is determined that all of the aforementioned chargers should be shut down, the power of each of the aforementioned chargers will be rapidly reduced. Charging control device.

3. A charging control device according to claim 1, It further includes a power distribution unit that controls the charging power output of each of the multiple chargers, The aforementioned processor, The power distribution unit outputs a charging power command indicating the total charging power obtained by summing the charging power output from each of the aforementioned multiple chargers. The aforementioned power distribution unit is If the total charging power corresponding to the charging power command falls below a threshold indicating the switching of the number of operating chargers, one or more of the chargers will be stopped. Charging control device.

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