Power supply system

Abstract

To provide a power supply system configured by connecting in parallel to a plurality of battery modules provided on electric motor vehicles for starting up more appropriately.SOLUTION: A system switch is installed between a stabilized power supply and a parallel connection point of power lines, and a plurality of module switches are installed between the parallel connection point and each battery control device. When the system is started, the system switch is turned on, the plurality of module switches are then turned on, and then the plurality of battery modules are started.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a power supply system, and more particularly, to a power supply system configured by connecting a plurality of vehicle-mounted battery modules in parallel.

Background Art

[0002] Conventionally, this type of power supply system has been proposed that includes a first power supply unit connected to a load via a first switch, a second power supply unit connected to the load via a second switch, and a third power supply unit having a lower internal resistance than the second power supply unit connected to the load via a third switch (see, for example, Patent Document 1). In this system, when the output voltage of the first power supply unit becomes lower than a first voltage, the first switch is turned off, and the second switch and the third switch are turned on. Then, the third switch is turned off when a predetermined connection period has elapsed. This stabilizes the voltage supplied to the load through switching between a plurality of power supplies.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] From the perspective of effective utilization of resources, it is conceivable that a plurality of battery modules mounted on an electric vehicle are used in a power supply system connected in parallel. In this case, when the system is started, it is necessary to supply power from a stabilized power supply to the control device that starts each battery module. However, if each battery module attempts to start at the same time, the output voltage of the stabilized power supply may drop, leading to cases where startup cannot be performed.

[0005] The primary purpose of the power supply system disclosed herein is to enable more proper startup of a power supply system configured by connecting multiple battery modules mounted on an electric vehicle in parallel. [Means for solving the problem]

[0006] The power supply system disclosed herein employs the following means to achieve the primary objectives described above.

[0007] The power supply system disclosed herein is A power supply system configured by connecting in parallel a plurality of in-vehicle battery modules, each having a battery and a battery control device for managing the battery, Each battery control unit of the aforementioned plurality of battery modules is connected in parallel to a stabilized power supply via a power line. A system switch is installed between the stabilized power supply and the parallel connection point of the power line, Multiple module switches are installed between the parallel connection point of the power lines and each battery control device, A system control device that receives power from the aforementioned stabilized power supply and controls the system, Equipped with, The control device for the aforementioned system is During system startup, after turning on the system switch, the system switches are sequentially turned on to start up multiple battery modules one after another. It is characterized by the following:

[0008] In the power supply system disclosed herein, each battery control device of multiple battery modules is connected in parallel to a stabilized power supply via a power line. A system switch is installed between the stabilized power supply and the parallel connection point of the power line, and multiple module switches are installed between the parallel connection point of the power line and each battery control device. When the system starts up, the system switch is turned on, and then the multiple module switches are turned on sequentially to start up the multiple battery modules. That is, the process of turning on the module switches and starting the battery control devices connected to these module switches is repeated sequentially to start up the battery modules. In this way, the battery modules are started sequentially, so that the drop in output voltage from the stabilized power supply that may occur when starting up the battery control devices of the battery modules simultaneously can be suppressed, and the system can be started up more properly. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing the configuration of the power supply system 20 as an embodiment of the present disclosure. [Figure 2] This flowchart shows an example of the system startup process. [Figure 3] This is an explanatory diagram showing an example of the time change in the voltage of the stabilized power supply during system startup for the power supply system 20 of the embodiment and the power supply system of the comparative example. [Modes for carrying out the invention]

[0010] Next, embodiments for implementing this disclosure will be described. Figure 1 is a schematic diagram showing the configuration of a power supply system 20 as an embodiment of this disclosure. The power supply system 20 is configured by connecting a plurality of battery modules 30a to 30n in parallel, and in addition to the plurality of battery modules 30a to 30n, it includes a system electronic control unit (hereinafter referred to as system ECU) 22, a stabilized power supply 51, a system switch 53, and a plurality of module switches 56a to 56n.

[0011] The battery module 30a is configured as an on-board module that supplies power to the motor for driving an electric vehicle, and is incorporated into the power supply system 20 for reuse after being installed and used in an electric vehicle. The battery module 30a has a battery 32a, a power control unit (PCU) 34a, a module electronic control unit (module ECU) 36a, and a battery electronic control unit (battery ECU) 38a. Note that battery modules 30b to 30n have the same configuration as battery module 30a.

[0012] Battery 32a is configured as, for example, a lithium-ion secondary battery. PCU 34a consists of an inverter that drives the traction motor and a boost converter that boosts the power from the battery and supplies it to the inverter. Battery ECU 38a receives detection values ​​from current sensors and voltage sensors (not shown) attached to the output terminals of battery 32a in order to manage battery 32a and calculates the battery's state of charge (SOC), etc. Module ECU 36a functions as an electronic control unit for the motor that drives the traction motor by controlling the boost converter and inverter in PCU 34a when battery module 30a is installed in the vehicle, and functions as a control device that starts up battery module 30a when battery module 30a is incorporated into the power supply system 20.

[0013] Batteries 32a to 32n are connected to output power lines 44 via module power lines 42a to 42n through PCUs 34a to 34n. Output power lines 44 are power lines for the output of the power supply system 20.

[0014] The stabilized power supply 51 is connected to an external power supply (e.g., a 200V commercial power supply) by a power line 50 and is configured as a power supply circuit that supplies a stable predetermined voltage (e.g., 5V) using a transformer, capacitor, etc. The stabilized power supply 51 is connected to a parallel connection power line 54 by a power line 52. A system switch 53 is attached to the power line 52. The parallel connection power line 54 is connected to module ECUs 36a to 36n by module power lines 55a to 55n. Module switches 56a to 56n are attached to each of the module power lines 55a to 55n. Therefore, by turning on the system switch 53 and each module switch 56a to 56n, the predetermined voltage from the stabilized power supply 51 can be supplied to each module ECU 36a to 36n.

[0015] The system ECU 22 receives power from the stabilized power supply 51 via the power line 52 and controls the power supply system 20. For example, the system ECU 22 turns the system switch 53 on and off, and also turns the switches 56a to 56n for each module on and off.

[0016] Next, the operation of the power supply system 20 in the embodiment configured in this way, particularly its operation during system startup, will be described. Figure 2 is a flowchart showing an example of the system startup process executed when the power supply system 20 starts up.

[0017] In the system startup process, first, the stabilized power supply 51 is turned on (step S100), and the system ECU 22 is started (step S110). Next, the system switch 53 is turned on (step S120), the battery modules 30a to 30n are started sequentially (steps S130 to S150), the system startup is completed (step S160), and the system startup process is terminated.

[0018] To start up the battery modules 30a to 30n among the sequentially arranged battery modules 30a to 30n, first, the module switch 56a connected to the first battery module 30a is turned on (step S130), and the module ECU 36a is started up (step S140). Then, it is determined whether or not there is any unstarted battery module (step S150). When it is determined that there is an unstarted battery module, the process returns to the process of turning on the module switch connected to the next battery module in step S130. By repeating steps S130 to S150 in this manner, the battery modules 30a to 30n are sequentially started up.

[0019] FIG. 3 is an explanatory diagram showing an example of a temporal change in the voltage of a stabilized power supply during system startup of the power supply system 20 according to the embodiment and a power supply system according to a comparative example. In the comparative example, with the hardware configuration of the power supply system 20 according to the embodiment, the system switch 53 and the module switches 56a to 56n are turned on simultaneously at the time of system startup. In the figure, voltage Vref is the minimum voltage required to start up the module ECUs 36a to 36n. In the comparative example, when system startup is started at time T1, the system switch 53 and the module switches 56a to 56n are turned on simultaneously. For this reason, the voltage from the stabilized power supply 51 drops greatly, falls below the minimum voltage Vref required to start up the module ECUs 36a to 36n, resulting in a failure of system startup. On the other hand, in the embodiment, when system startup is started at time T1, the system switch 53 is turned on, and thereafter, the module switches 56a to 56n are turned on sequentially. For this reason, although a slight voltage drop is observed in the voltage from the stabilized power supply 51 when the switches are turned on, the voltage does not fall below the minimum voltage Vref required to start up the module ECUs 36a to 36n, and the system starts up normally.

[0020] In the power supply system 20 of the embodiment described above, the respective batteries 32a to 32n of the plurality of reused battery modules 30a to 30n are connected in parallel to the output power line 44 via the module power lines 42a to 42n, and the module ECUs 36a to 36n of the battery modules 30a to 30n are connected in parallel to the power supply line 52 connected to the stabilized power supply 51 via the module power supply lines 55a to 55n and the parallel connection power supply line 54. A system switch 53 is attached to the power supply line 52, and module switches 56a to 56n are attached to the respective module power supply lines 55a to 55n. When the system is started up, after turning on the system switch 53, the module switches 56a to 56n are turned on sequentially to start up the respective module ECUs 36a to 36n sequentially. Since the battery modules 30a to 30n are started sequentially in this manner, a significant drop in the output voltage from the stabilized power supply 51 that may occur when starting the battery modules 30a to 30n simultaneously can be suppressed, and the power supply system 20 can be started more appropriately.

[0021] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section "Means for Solving the Problem" will be explained. In the embodiment, the batteries 32a to 32n correspond to "batteries", the battery modules 30a to 30n correspond to "battery modules", the stabilized power supply 51 corresponds to a "stabilized power supply", the system switch 53 corresponds to a "system switch", the parallel connection power supply line 54 corresponds to a "parallel connection point", the module ECUs 36a to 36n correspond to "battery control devices", the module switches 56a to 56n correspond to "module switches", and the system ECU 22 corresponds to a "system control device".

[0022] Furthermore, the correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem is merely an example to specifically explain the form in which the embodiment implements the invention described in the section on means for solving the problem, and does not limit the elements of the invention described in the section on means for solving the problem. In other words, the interpretation of the invention described in the section on means for solving the problem should be based on the description in that section, and the embodiment is merely one specific example of the invention described in the section on means for solving the problem.

[0023] Although the present disclosure has been described above using embodiments, the present disclosure is not limited in any way to these embodiments, and can of course be implemented in various forms without departing from the gist of the present disclosure. [Industrial applicability]

[0024] This disclosure can be used in industries such as the manufacturing of power supply systems. [Explanation of Symbols]

[0025] 20 Power supply system, 22 System electronic control unit (System ECU), 30a~30n Battery module, 32a~32n Battery, 34a~34n Power control unit (PCU), 36a~36n Module electronic control unit (Module ECU), 42a~42n Module power line, 44 Output power line, 50 Power line, 51 Regulated power supply, 52 Power line, 53 System switch, 54 Parallel connection power line, 55a~55n Module power line, 56a~56n Module switch.

Claims

[Claim 1] A power supply system comprising a battery, a power control unit that controls the input and output of the battery, and a battery control device that manages the battery and controls the power control unit, wherein multiple on-board battery modules are connected in parallel to supply power to the traction motor of an electric vehicle when installed in a vehicle, It is equipped with a stabilized power supply that is connected to an external power supply and supplies a predetermined voltage, Each battery in the aforementioned plurality of battery modules is connected to an output power line via a power control unit. Each battery control unit of the plurality of battery modules is connected in parallel to the stabilized power supply by a power line. A system switch is installed between the stabilized power supply and the parallel connection point of the power line, Multiple module switches are installed between the parallel connection point of the power lines and each battery control device, A system control device that receives power from the aforementioned stabilized power supply and controls the system, Equipped with, The control device for the aforementioned system is During system startup, the system switch is turned on, and then the switches for multiple modules are turned on sequentially to start up multiple battery modules one after another. A power supply system characterized by the following features.

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