Power supply equipment

Abstract

This improves convenience by reducing the time required for diagnosing stuck switches on the battery connection status and for pre-charging capacitors. [Solution] The control unit sets the first switch (S1), the second switch (S2), and the third switch (S3) to the off state and performs a continuity lock diagnosis based on the capacitor voltage to determine whether at least one of the first switch (S1), the second switch (S2), and the third switch (S3) is stuck in a conductive state. After the continuity lock diagnosis, the control unit sets at least one of the first switch (S1), the second switch (S2), and the third switch (S3) to the on state and performs an off-state lock diagnosis based on the capacitor voltage to determine whether the first switch (S1), the second switch (S2), and the third switch (S3) are stuck in an off state.

Description

Technical Field

[0001] The present invention relates to a power supply device.

Background Art

[0002] In recent years, research and development have been conducted on secondary batteries that contribute to energy efficiency in order to enable more people to access affordable, reliable, sustainable, and advanced energy.

[0003] In the technology related to secondary batteries, conventionally, a power supply device that can switch the connection state of two batteries between series connection and parallel connection to supply power from the two batteries has been known (see, for example, Patent Document 1). Patent Document 1 discloses an electric circuit corresponding to a power supply device including two batteries that are connected in series during running and in parallel during charging by switching the conduction state and the cutoff state of two contacts corresponding to switches. Further, the electric circuit described in Patent Document 1 simultaneously performs pre-charging of a capacitor and determination of the presence or absence of a contact failure when the vehicle is started.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the technology related to secondary batteries, there is a need for a technology that enables the connection of two batteries to be changed to series connection, parallel connection, or single connection during operation of the power supply device (while the power supply device is in use) according to user requirements. Note that at least three switches are required to enable the change of the connection of two batteries to series connection, parallel connection, or single connection. If the user instructs the power supply unit to switch the connection status of the two batteries while the unit is operating, and each time the unit performs a check for sticking in the three switches that switch the battery connection status and pre-charges the capacitors, it takes too much time. As a result, the unit cannot immediately switch to the battery connection desired by the user, leading to a decrease in convenience. To solve the above-mentioned problems, this invention aims to improve convenience in a power supply device that can switch the connection state of two batteries between series, parallel, or single-unit connection, by shortening the time required for diagnosing sticking of the switch that switches the battery connection state and for precharging the capacitor. Ultimately, this will contribute to energy efficiency. [Means for solving the problem]

[0006] The power supply device comprises an inverter, a first battery and a second battery that supply power to the inverter, and a capacitor provided on the inverter and connected to at least one of the first battery and the second battery, the power supply device comprising: a first switch disposed between the negative electrode of the first battery and the positive electrode of the second battery, which switches the connection state between the negative electrode of the first battery and the positive electrode of the second battery to a conduction state or a disconnection state; a second switch disposed between one terminal of the capacitor and the positive electrode of the second battery, which switches the connection state between the one terminal of the capacitor and the positive electrode of the second battery to a conduction state or a disconnection state; a third switch disposed between the other terminal of the capacitor and the negative electrode of the first battery, which switches the connection state between the other terminal of the capacitor and the negative electrode of the first battery to a conduction state or a disconnection state; a voltage measuring instrument for measuring the capacitor voltage, which is the voltage of the capacitor; and a control for the connection states of the first switch, the second switch and the third switch, and the first battery The inverter comprises a control unit that controls the output state of power from the first battery or the second battery, wherein when a trigger for starting the inverter occurs, the control unit sets the first switch, the second switch, and the third switch to an off state and sets the inverter to an output state of power from at least one of the first battery and the second battery, and performs a continuity lock diagnosis to diagnose whether at least one of the first switch, the second switch, and the third switch is stuck in a conductive state based on the capacitor voltage in that state, and after the continuity lock diagnosis, it sets the inverter to an off state and sets the inverter to an output state of power from at least one of the first battery and the second battery, and performs an off lock diagnosis to diagnose whether at least one of the first switch, the second switch, and the third switch is stuck in an off state based on the capacitor voltage in that state, [Effects of the Invention]

[0007] This can improve convenience by reducing the time required for diagnosing sticking in the battery connection switch and for pre-charging the capacitor. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example of the configuration of a motorcycle according to an embodiment. [Figure 2] This figure shows an example of the configuration of a power supply device. [Figure 3] This is a schematic diagram showing the details of the battery configuration. [Figure 4] This figure shows an example of the first battery being connected independently. [Figure 5] This figure shows an example of a state where the second battery is connected independently. [Figure 6] This figure shows an example of a configuration in which the first and second batteries are connected in series. [Figure 7] This figure shows an example of a capacitor being connected to a resistor. [Figure 8] This diagram shows a table that explains the details of the diagnostic items. [Figure 9] This is a flowchart showing the operation of the ECU. [Figure 10] This is a flowchart showing the operation of the ECU. [Modes for carrying out the invention]

[0009] (Embodiment) [1. Structure] [1-1. Vehicle Configuration] First, the configuration of the motorcycle 1 according to this embodiment will be described with reference to Figure 1. Figure 1 is a diagram showing an example of the configuration of the motorcycle according to this embodiment. Motorcycle 1 is an electric motorcycle, a type of saddle-type electric vehicle. Motorcycle 1 is equipped with a front wheel 3, which is the steering wheel, and a rear wheel 4, which is the drive wheel. The front wheel 3 is rotatably supported by a pair of front forks 6. The front wheel 3 is also steerable by a handlebar 2.

[0010] The rear wheel 4 is supported at the rear of a swingarm 20 that is pivotably supported on the vehicle frame F. The motorcycle 1 is a unit swing type motorcycle. The swingarm 20 is equipped with a motor MT that drives the motorcycle 1 and a reduction mechanism (not shown) that reduces the driving force of the motor MT and transmits it to the rear wheel axle. A rear fender covering the rear upper part of the rear wheel 4 is supported at the rear end of the swingarm 20 via a fender support arm 40. The lower end of a rear cushion 7, which is a rear suspension component, is connected to the fender support arm 40.

[0011] The vehicle frame F is equipped with a head pipe 12 at its front end. The head pipe 12 holds the front wheel 3 in a steerable manner via the steering stem 11 and the left and right front forks 6. A headlight HL (not shown) is fixed to the head pipe 12. The vehicle frame F further comprises a pair of left and right upper frames 13, a pair of left and right lower frames 14, and a pair of left and right seat frames 15. The upper frames 13 extend diagonally downward and rearward from approximately the middle region in the vertical direction of the head pipe 12. The lower frames 14 extend downward from the lower region of the head pipe 12, then extend towards the rear of the vehicle, and from their rear ends extend upward with a slight incline towards the rear. The seat frames 15 extend diagonally upward and rearward from approximately the middle position in the front-rear direction of the upper frames 13. The lower frame 14 is connected by the middle frame 16. Furthermore, the rear region of the lower frame 14 and the rear region of the seat frame 15 are connected by the support frame 17.

[0012] The motor MT is held by the main arm of the swing arm 20 and is disposed on the left side of the rear wheel 4. The motor MT is an inner rotor type motor and includes an inner rotor having a motor output shaft and a stator. The motor MT is disposed in the rear region of the main arm of the swing arm 20.

[0013] The motorcycle 1 includes, as the battery BT, a first battery BT1 and a second battery BT2 having equal electromotive forces. Equal electromotive forces include, for example, equal rated voltages and equal nominal voltages. Each of the first battery BT1 and the second battery BT2 supplies power to the motor MT. That the battery BT supplies power can also be rephrased as the battery BT discharges. The first battery BT1 and the second battery BT2 are arranged in the front-rear direction inside a battery storage device 64 provided below the seat. Each of the first battery BT1 and the second battery BT2 is formed in a substantially rectangular parallelepiped shape and has the same configuration as each other. The first battery BT1 and the second battery BT2 are configured of lithium ion batteries, for example, as energy storage capable of charge and discharge. The first battery BT1 and the second battery BT2 are configured to be detachable from the vehicle body. In other words, the first battery BT1 and the second battery BT2 are configured to be detachable from the battery storage device 64.

[0014] [1-2. Configuration of Power Supply Device] Next, referring to FIG. 2, the configuration of the power supply device 5 will be described. FIG. 2 is a diagram showing an example of the configuration of the power supply device 5. The power supply device 5 is mounted on the motorcycle 1. As shown in FIG. 2, the power supply device 5 includes a first battery BT1 and a second battery BT2. The power supply device 5 supplies power from the first battery BT1 and the second battery BT2 to a first load L1. The first load L1 is, for example, a PCU (Power Control Unit) 51 or the motor MT. The PCU51 converts the DC power supplied from at least one of the first battery BT1 and the second battery BT2 into three-phase AC power based on control signals input from the ECU (Electronic Control Unit), which will be described later, and supplies power to drive the motor MT, which is a three-phase AC motor. The PCU51 is a so-called inverter. The PCU51 includes an input section corresponding to the positive and negative of the DC power input from at least one of the first battery BT1 and the second battery BT2, and an output section corresponding to the three-phase power supplied to the motor MT. The PCU 51 includes a switching unit 60 as such an input and output unit. The first battery BT1 and the second battery BT2 supply power to the motor MT, which is the first load L1, via the switching unit 60 of the PCU 51. The switching unit 60 is a so-called three-phase modulation inverter circuit. The switching unit 60 includes a switch (not shown) that can be connected to or disconnected from the circuit of the power supply device 5 by the ECU.

[0015] The ECU includes a processor 511 such as a CPU (Central Processing Unit) and memory 512 such as ROM (Read Only Memory).

[0016] Memory 512 is a storage device that non-volatilely stores programs and data executed by the processor 511. Memory 512 is composed of a magnetic storage device, a semiconductor storage element such as flash ROM, or other types of non-volatile storage devices. Memory 512 may also include RAM (Random Access Memory) which constitutes the work area of ​​the processor 511. Memory 512 stores data processed by the processor 511 and control programs executed by the processor 511. The processor 511 may consist of a single processor, or it may be configured so that multiple processors function as the processor 511.

[0017] Based on user input, the ECU outputs control signals to switch each of the following switches, which are examples of switches described later—the first switch S1, the second switch S2, and the third switch S3—to either a conduction state or an interruption state. User input may include, for example, instructions for series connection or parallel connection of the first battery BT1 and the second battery BT2. Alternatively, user input may include instructions for single-unit connection of the first battery BT1 or single-unit connection of the second battery BT2.

[0018] The power supply device 5 includes, for example, an operating mechanism (not shown) that receives input from the user. The ECU receives input from the user via this operating mechanism. The operating mechanism is, for example, a start switch or ignition switch (not shown) provided in the vehicle, which is operated by the user when starting the vehicle. The power supply device 5 is started in conjunction with the operation of the aforementioned operating mechanism. The state in which the power supply device 5 is started means that, triggered by the operation of the operating mechanism, the power supply device 5 changes from a state in which it cannot supply power to the outside to a state in which it can supply power. Furthermore, the ECU, triggered by the activation of the power supply device 5, outputs control signals to switch the output states of the first battery BT1 and the second battery BT2 in a predetermined order and timing. In addition, the ECU outputs control signals to switch each of the first switch S1, second switch S2, third switch S3, and discharge switch S4 to a conduction state or an interruption state. An ECU corresponds to an example of a "control unit".

[0019] The power supply device 5 includes, as an example of switches, a first switch S1, a second switch S2, a third switch S3, and a discharge switch S4. The ECU outputs a control signal to the first switch S1 to switch between a conduction state and an interruption state, thereby switching the first switch S1 between a conduction state and an interruption state. The ECU also outputs a control signal to the second switch S2 to switch between a conduction state and an interruption state, thereby switching the second switch S2 between a conduction state and an interruption state. The ECU also outputs a control signal to the third switch S3 to switch between a conduction state and an interruption state, thereby switching the third switch S3 between a conduction state and an interruption state. The ECU also outputs a control signal to the discharge switch S4 to switch between a conduction state and an interruption state, thereby switching the discharge switch S4 between a conduction state and an interruption state.

[0020] Each of the first switch S1, second switch S2, third switch S3, and discharge switch S4 is, for example, composed of a contactor. In the following explanation, "ON" will be used to indicate a "continuous" connection state, and "OFF" will be used to indicate a "disconnected" connection state. Furthermore, in the following explanation, when the ECU outputs a control signal to turn on the first switch S1, second switch S2, third switch S3, or discharge switch S4, and switches them to the ON position, this is referred to as "turning the switch ON." When the ECU outputs a control signal to turn off the first switch S1, second switch S2, third switch S3, or discharge switch S4, and switches them to the OFF position, this is referred to as "turning the switch OFF."

[0021] The first switch S1 is positioned between the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2, and receives the above-mentioned control signal from the ECU to switch the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2 between a conductive state and an interrupted state.

[0022] In other words, the ECU makes the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2 conductive by turning on the first switch S1. Conversely, the ECU makes the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2 non-conductive by turning off the first switch S1.

[0023] The second switch S2 is positioned between the positive terminal of the PCU 51 and the positive terminal of the second battery BT2, and receives the above-mentioned control signal from the ECU to switch the positive terminal of the PCU 51 and the positive terminal of the second battery BT2 between a conductive state and an interrupted state. In other words, the ECU makes the positive terminal of the PCU51 and the positive terminal of the second battery BT2 conductive by turning on the second switch S2. Conversely, the ECU makes the positive terminal of the PCU51 and the positive terminal of the second battery BT2 non-conductive by turning off the second switch S2.

[0024] The third switch S3 is positioned between the negative terminal of the PCU 51 and the negative terminal of the first battery BT1, and receives the above-mentioned control signal from the ECU to switch the negative terminal of the PCU 51 and the negative terminal of the first battery BT1 between a conductive state and an interrupted state. In other words, the ECU makes the negative terminal of the PCU 51 and the negative terminal of the first battery BT1 conductive by turning on the third switch S3. Conversely, the ECU makes the negative terminal of the PCU 51 and the negative terminal of the first battery BT1 disconnected by turning off the third switch S3.

[0025] Furthermore, as shown in Figure 2, the positive terminal of the second battery BT2 is connected to the first switch S1 at the first connection terminal T1. Also, the negative terminal of the first battery BT1 is connected to the first switch S1 at the second connection terminal T2.

[0026] The power supply device 5 includes a capacitor C1 and a resistor R1, which are also provided in the PCU 51.

[0027] Capacitor C1 is connected to the first battery BT1 and the second battery BT2. Resistor R1 is connected in parallel with capacitor C1. Power supply device 5 includes a discharge switch S4. Discharge switch S4 is composed of a semiconductor switch such as an FET (Field Effect Transistor).

[0028] The discharge switch S4 can be switched ON and OFF in response to the control signal mentioned above from the ECU.

[0029] The discharge switch S4 is connected in series with the resistor R1 of the PCU51 and switches the PCU51 and capacitor C1 between a conductive state and an interrupted state. In other words, the ECU makes capacitor C1 and resistor R1 conduct by outputting a control signal to turn on the discharge switch S4. Conversely, the ECU makes capacitor C1 and resistor R1 disconnect by turning off the discharge switch S4.

[0030] The power supply device 5 includes a voltage measuring instrument 30 capable of measuring the capacitor voltage of capacitor C1. The voltage measuring instrument 30 is connected between the wire connecting the positive terminal of the first battery BT1 and capacitor C1, and the wire connecting the negative terminal of the second battery BT2 and capacitor C1. The ECU acquires the capacitor voltage of capacitor C1 measured by the voltage measuring instrument 30. Alternatively, the voltage measuring instrument 30 may be a measuring instrument for measuring the capacitance of capacitor C1. In this case, the ECU calculates the capacitor voltage of capacitor C1 from the capacitance of capacitor C1.

[0031] [1-3. Battery and Capacitor Configuration] Refer to Figure 3 for a detailed explanation of the battery BT configuration. Figure 3 is a schematic diagram showing the detailed configuration of the battery BT. The battery BT is equipped with a control unit such as a BMU (Battery Managing Unit) (not shown in the diagram) and is connected to the ECU. The battery BT comprises a battery body 70. One end of the discharge switch unit 71 is connected to the positive terminal side of the battery body 70, and the other end of the discharge switch unit 71 is connected to the charge switch unit 72. Additionally, one end of the precharge switch unit 73 is connected to the positive terminal side of the battery body 70, and the other end of the precharge switch unit 73 is connected between the discharge switch unit 71 and the charge switch unit 72.

[0032] In this manner, the discharge switch unit 71 and the precharge switch unit 73 are connected in parallel to the positive electrode side of the battery body 70. Furthermore, the charge switch unit 72 is connected in series to the discharge switch unit 71 and the precharge switch unit 73, which are connected in parallel.

[0033] The charging switch unit 72 includes a charging switch 76 and a diode 77 that allows current to flow from the battery body 70 toward the outside of the battery BT. The charging switch unit 72 is controlled to turn ON when the battery body 70 is being charged, and allows current to flow from the outside of the battery BT toward the battery body 70.

[0034] The discharge switch section 71 includes a discharge switch 74 and a diode 75 that allows current to flow from the outside of the battery BT towards the battery body 70. The discharge switch section 71 is controlled to turn ON when the battery body 70 is discharged, allowing current to flow from the battery body 70 towards the outside of the battery BT.

[0035] The precharge switch section 73 includes a precharge switch 78, a diode 79 that allows current to flow from outside the battery BT towards the battery body 70, and a precharge resistor 80R. When precharging the capacitor C1, which will be described later, the precharge switch 78 is controlled to ON, and the charge switch 76 and discharge switch 74 are controlled to OFF, allowing current to flow from the battery body 70 towards the outside of the battery BT due to discharge from the battery body 70. During the precharging of the capacitor C1, the current flowing due to discharge by the precharge switch section 73 is adjusted to be smaller than the current flowing due to discharge by the discharge switch section 71 by the precharge resistor 80R. This suppresses the inrush current during the precharging of the capacitor C1.

[0036] The discharge switch 74, the charge switch 76, and the precharge switch 78 are, for example, semiconductor switches. The discharge switch 74, the charge switch 76, and the precharge switch 78 are not limited to these, and may also be contactors.

[0037] Furthermore, a battery resistor 80r is connected in series with the discharge switch section 71, the charge switch section 72, and the precharge switch section 73. The battery resistor 80r suppresses the inrush current during charging and discharging of the battery BT. The resistance value of the battery resistor 80r is smaller than the resistance value of the precharge resistor 80R.

[0038] In Figure 3 and in Figures 5, 6, and 7 described later, for the discharge switch 74, charge switch 76, precharge switch 78, first switch S1, second switch S2, third switch S3, and discharge switch S4, a solid line drawn along the diagonal of the corresponding rectangular mark indicates that it is OFF, while the absence of the diagonal line indicates that it is ON.

[0039] In Figure 3, the discharge switch 74 and the charge switch 76 are OFF, and the precharge switch 78 is ON. In this case, it corresponds to the state of battery BT when precharging capacitor C1 with the power output of battery BT. Although not shown in the figure, battery BT1 can be discharged by turning the charge switch 76 and the precharge switch 78 OFF and turning the discharge switch 74 ON. If all three—discharge switch 74, charge switch 76, and precharge switch 78—are OFF, battery BT does not conduct.

[0040] [1-4. When the first battery is connected individually] Figure 4 shows an example of a state in which the first battery BT1 is connected to the PCU 51 on its own. For convenience, in the following explanation, the state in which the first battery BT1 is connected to the PCU 51 on its own will be referred to as the first mode Co1.

[0041] In the first mode Co1, the ECU outputs control signals to turn off the first switch S1, the second switch S2, and the third switch S3.

[0042] By turning the first switch S1 OFF, the second switch S2 OFF, and the third switch S3 ON, the first battery BT1 is connected to the PCU 51 individually. For example, current flows through the PCU51 as shown by the dashed line. That is, current flows from the negative terminal of the PCU51, sequentially through the third switch S3 and the second connection terminal T2, towards the negative terminal of the first battery BT1. Also, current flows from the positive terminal of the first battery BT1 towards the positive terminal of the PCU51. Furthermore, capacitor C1 stores a charge corresponding to the electromotive force of the first battery BT1.

[0043] [1-5. When the second battery is connected separately] Figure 5 shows an example of a state in which the second battery BT2 is connected to the PCU51 independently. For convenience, in the following explanation, the state in which the second battery BT2 is connected to the PCU51 independently will be referred to as second mode CO2.

[0044] In the second mode, CO2, the ECU turns off the first switch S1, turns on the second switch S2, and turns off the third switch S3.

[0045] By turning the first switch S1 OFF, the second switch S2 ON, and the third switch S3 OFF, the second battery BT2 is connected to the PCU51 independently.

[0046] For example, current flows through the PCU51 as shown by the dashed line. That is, current flows from the negative terminal of the PCU51 to the negative terminal of the second battery BT2. Also, current flows from the positive terminal of the second battery BT2 to the positive terminal of the PCU51, sequentially through the first connection terminal T1 and the second switch S2. Furthermore, capacitor C1 stores a charge corresponding to the electromotive force of the second battery BT2.

[0047] [1-6. When the first and second batteries are connected in series] Next, with reference to Figure 6, we will describe the case in which the first battery BT1 and the second battery BT2 are connected in series to the PCU 51. Figure 6 is a diagram showing an example of the state in which the first battery BT1 and the second battery BT2 are connected in series to the PCU 51. For convenience, in the following description, the state in which the first battery BT1 and the second battery BT2 are connected in series to the PCU 51 will be referred to as the third mode Co3.

[0048] In the third mode, Co3, the ECU turns on the first switch S1, turns off the second switch S2, and turns off the third switch S3.

[0049] By turning on the first switch S1, turning off the second switch S2, and turning off the third switch S3, the first battery BT1 and the second battery BT2 are connected in series to the PCU 51.

[0050] For example, current flows through the PCU51 as shown by the dashed line. That is, current flows from the negative terminal of the PCU51 to the negative terminal of the second battery BT2. Also, current flows from the positive terminal of the second battery BT2 to the negative terminal of the first battery BT1, sequentially through the first connection terminal T1, the first switch S1, and the second connection terminal T2. Furthermore, current flows from the positive terminal of the first battery BT1 to the positive terminal of the PCU51. Furthermore, capacitor C1 stores a charge corresponding to the sum of the electromotive forces of the first battery BT1 and the second battery BT2. Furthermore, if the first battery BT1 and the second battery BT2 are connected in parallel to the PCU 51, the ECU will turn off the first switch S1 and turn on the second switch S2 and the third switch S3.

[0051] [1-7. When the capacitor is discharged] Figure 7 shows an example of a state in which capacitor C1 is connected to resistor R1. For convenience, in the following explanation, the state in which capacitor C1 is connected to resistor R1 will be referred to as discharge mode Co4.

[0052] In discharge mode Co4, the ECU turns off the first switch S1, the second switch S2, the third switch S3, and the discharge switch S4.

[0053] By turning the first switch S1, the second switch S2, and the third switch S3 OFF, and turning the discharge switch S4 ON, capacitor C1 is connected to resistor R1. For example, when charge is stored in capacitor C1, current flows through the circuit consisting of capacitor C1 and resistor R1, as shown by the dashed line. In this way, in discharge mode Co4, a closed circuit is formed by capacitor C1 and resistor R1, the charge stored in capacitor C1 is discharged by resistor R1, the capacitor voltage of capacitor C1 decreases, that is, capacitor C1 is discharged.

[0054] [2. Operation] Figure 8 is a diagram showing a table that explains the details of the diagnostic items. The table shown in Figure 8 summarizes the diagnostic conditions for each diagnostic item set by the ECU, the cause estimated from the abnormality, and the control contents for the first battery BT1, second battery BT2, first switch S1, second switch S2, third switch S3, and discharge switch S4, corresponding to the number of the diagnostic item.

[0055] Figures 9 and 10 are flowcharts showing the operation of the ECU. As shown in Figure 9, the ECU determines whether the power supply device 5 has started (step ST1). If the power supply device 5 has not started (ST1:NO), the determination in step ST1 is repeated. If the power supply device 5 has started (ST1:YES), the ECU sets it to diagnostic item 1, which will be described later, and obtains the capacitor voltage of capacitor C1 (step ST2). Thereafter, unless there is an abnormality, the ECU sequentially sets diagnostic items 1 through 7.

[0056] Refer to Figure 8 to detail each diagnostic item 1-7. In each diagnostic item, the charge switch 76 and the discharge switch 74 are OFF. Therefore, if the precharge of the first battery BT1 or the second battery BT2 is OFF, the first battery BT1 or the second battery BT2 will have the discharge switch 74, charge switch 76, and precharge switch 78 all OFF, and will not conduct electricity. Furthermore, the setting of each diagnostic item is performed by the ECU by outputting control signals to each switch. Setting each diagnostic item performed by the ECU includes setting at least one of the first switch S1, second switch S2, third switch S3, and discharge switch S4 to ON or OFF. Setting an ECU to turn on a switch is different from actually turning the switch on. It means that the ECU outputs a control signal to the switch to create a conductive state. In other words, the ECU setting a switch to turn on does not always mean that the switch to which the control signal is output will actually turn on. This is because even if the ECU outputs a control signal to turn on a switch, if the switch is faulty, the switch will not actually turn on. Setting an ECU to turn off a switch is not the same as actually turning the switch off; it means the ECU outputs a control signal to the switch to shut it off. In other words, the ECU setting a switch to turn off does not always mean that the switch to which the control signal is output will actually turn off. This is because even if the ECU outputs a control signal to turn off a switch, if the switch is faulty, the switch will not actually turn off.

[0057] In diagnostic item 1, the first switch S1, second switch S2, third switch S3, and discharge switch S4 are set to OFF. In diagnostic item 1, the capacitor voltage of capacitor C1 is 0V under normal conditions, and anything else under abnormal conditions. In diagnostic item 1, it is suspected that the cause of the abnormality is sticking of one of the following: charge switch 76, discharge switch 74, precharge switch 78, first switch S1, second switch S2, or third switch S3. In diagnostic item 1, the capacitor voltage of capacitor C1 is 0V under normal conditions. This is because capacitor C1 is discharged after the power supply device 5 stops, and therefore no charge is stored in capacitor C1 when the power supply device 5 starts up.

[0058] In diagnostic item 2, the settings are configured to turn OFF the first switch S1, the second switch S2, the third switch S3, and the discharge switch S4, and the settings are configured to precharge capacitor C1 with 48V from the first battery BT1. Under normal conditions, capacitor C1 and the first battery BT1 are not connected, so the capacitor voltage of capacitor C1 is measured as 0V. On the other hand, under abnormal conditions, the capacitor voltage of capacitor C1 is measured as 48V, which means that the first battery BT1 is connected. Therefore, it is presumed that the cause of the abnormality is that the third switch S3 remains ON despite the ECU outputting a control signal to turn it OFF. The diagnostic item 2, which is set by the ECU, is a diagnosis of continuity sticking of the third switch. The diagnosis of continuity sticking of the third switch is an example of a continuity sticking diagnosis.

[0059] In diagnostic item 3, the settings are configured to turn OFF the first switch S1, the second switch S2, the third switch S3, and the discharge switch S4, and the settings are configured to precharge capacitor C1 with 48V using the second battery BT2. Under normal conditions, capacitor C1 and the second battery BT2 are not connected, so the capacitor voltage of capacitor C1 is measured as 0V. On the other hand, under abnormal conditions, the capacitor voltage of capacitor C1 is measured as 48V, which means that the second battery BT2 is connected. Therefore, it is presumed that the cause of the abnormality is that the second switch S2 remains ON despite the ECU outputting a control signal to turn it OFF. Diagnostic item 3, the diagnosis by setting the ECU, is a diagnosis of second switch continuity sticking. The second switch continuity sticking diagnosis is an example of a continuity sticking diagnosis.

[0060] In diagnostic item 4, the settings are configured to turn OFF the first switch S1, the second switch S2, the third switch S3, and the discharge switch S4, and the settings are configured to precharge capacitor C1 at 96V using the first battery BT1 and the second battery BT2. Under normal conditions, capacitor C1 is not connected to the first battery BT1 and the second battery BT2, so the capacitor voltage of capacitor C1 is measured as 0V. On the other hand, in the case of an abnormality, the capacitor voltage of capacitor C1 is measured as 96V, and the first battery BT1 and the second battery BT2 are connected. Therefore, it is presumed that the cause of the abnormality is that the first switch S1 remains ON despite the ECU outputting a control signal to turn it OFF. Diagnostic item 4, the diagnosis by setting the ECU, is a diagnosis of first switch continuity sticking. The first switch continuity sticking diagnosis is an example of a continuity sticking diagnosis.

[0061] In diagnostic item 5, the first switch S1, the second switch S2, and the discharge switch S4 are set to OFF, and the third switch S3 is set to ON, so that pre-charging of capacitor C1 at 24V corresponding to a predetermined voltage is performed by the first battery BT1. In diagnostic item 5, when the capacitor voltage of capacitor C1 reaches a predetermined voltage, capacitor C1 is disconnected from the circuit of the power supply device 5. Specifically, capacitor C1 is disconnected from the circuit of the power supply device 5 when the discharge switch 74, charge switch 76, precharge switch 78, first switch S1, second switch S2, third switch S3, and discharge switch S4 are turned OFF, and the switching unit 60 and capacitor C1 are turned OFF. Note that the specified voltage is not 24V, but can be changed as appropriate as long as it is a value less than 48V, which is the electromotive force of the first battery BT1 or the second battery BT2. Diagnostic item 5 corresponds to the state of the first mode Co1 shown in Figure 4. Under normal conditions, capacitor C1 and the first battery BT1 are conductive, and the capacitor voltage of capacitor C1 is measured to a predetermined voltage (24V in this embodiment). On the other hand, in the event of an abnormality, the capacitor voltage of capacitor C1 is measured to be 0V, which means that the first battery BT1 is not connected. Therefore, it is presumed that the cause of the abnormality is that the third switch S3 remains OFF despite the ECU outputting a control signal to turn it ON. Thus, if there are no abnormalities in diagnostic items 1 to 4, precharging of capacitor C1 is performed for the first time in diagnostic item 5. The diagnosis in diagnostic item 5, which is set by the ECU, is a diagnosis of the third switch being stuck off.

[0062] In diagnostic item 6, the first switch S1, the third switch S3, and the discharge switch S4 are set to OFF, and the second switch S2 is set to ON, so that the second battery BT2 precharges capacitor C1 at 48V. With the settings of diagnostic item 5, capacitor C1 has a charge corresponding to a predetermined voltage stored, so the precharge in diagnostic item 6 is achieved faster than when precharging capacitor C1 from a state where the capacitor voltage is 0V. Diagnostic item 6 corresponds to the state of second mode Co2 shown in Figure 5. Under normal conditions, capacitor C1 and the second battery BT2 are connected, and the capacitor voltage of capacitor C1 is measured at 48V. On the other hand, under abnormal conditions, the capacitor voltage of capacitor C1 is measured at 0V, which means that the second battery BT2 is not connected. Therefore, it is presumed that the cause of the abnormality is that the second switch S2 remains OFF despite the ECU outputting a control signal to turn it ON. Diagnostic item 6, the diagnosis by setting the ECU, is a diagnosis of the second switch being stuck off.

[0063] In diagnostic item 7, the second switch S2, the third switch S3, and the discharge switch S4 are set to OFF, and the first switch S1 is set to ON, so that the first battery BT1 and the second battery BT2 precharge capacitor C1 at 96V. Diagnostic item 7 corresponds to the state of the third mode Co3 shown in Figure 6. Under normal conditions, capacitor C1 is conductive with the first battery BT1 and the second battery BT2, and the capacitor voltage of capacitor C1 is measured to be 96V. On the other hand, under abnormal conditions, the capacitor voltage of capacitor C1 is measured to be 48V, and the first battery BT1 is not connected. In this case, it is presumed that the cause of the abnormality is that the first switch S1 remains OFF despite the ECU outputting a control signal to turn it ON. The diagnosis performed by the ECU setting in diagnostic item 7 is a diagnosis of first switch interruption sticking.

[0064] Thus, in the ECU's diagnostics, controlling the power output state of the first battery BT1 or the second battery BT2 means that the ECU outputs a control signal to switch the precharge switch 78 between ON and OFF, while the charge switch 76 and discharge switch 74 remain OFF so that precharging can be performed.

[0065] Returning to the explanation of Figures 9 and 10, after step ST2, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 0V), that is, whether there is an abnormality (step ST3).

[0066] If there is no abnormality (Step ST3: NO), the ECU sets the diagnostic conditions for diagnostic item 2 and acquires the capacitor voltage of capacitor C1 (Step ST4). The diagnosis for diagnostic item 2 is completed quickly because, under normal circumstances, capacitor C1 is not connected to battery BT, so no pre-charging of capacitor C1 occurs. Next, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 0V), that is, whether there is an abnormality (step ST5).

[0067] If there is no abnormality (step ST5: NO), the ECU sets the diagnostic conditions for diagnostic item 3 and acquires the capacitor voltage of capacitor C1 (step ST6). The diagnosis for diagnostic item 3 is completed quickly because, under normal circumstances, capacitor C1 is not connected to battery BT, so no pre-charging of capacitor C1 occurs. Next, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 0V), that is, whether there is an abnormality (step ST7).

[0068] If there is no abnormality (step ST7: NO), the ECU sets the diagnostic conditions for diagnostic item 4 and acquires the capacitor voltage of capacitor C1 (step ST8). The diagnosis for diagnostic item 4 is completed quickly because, under normal circumstances, capacitor C1 is not connected to battery BT, so no pre-charging of capacitor C1 occurs. Next, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 0V), that is, whether there is an abnormality (step ST9).

[0069] If there is no abnormality (step ST9: NO), the ECU sets the diagnostic conditions for diagnostic item 5 and acquires the capacitor voltage of capacitor C1 (step ST10). The diagnosis for diagnostic item 5 is performed under normal conditions, taking time for the capacitor voltage of capacitor C1 to rise from approximately 0V to approximately 24V. Next, referring to Figure 10, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 24V), that is, whether there is an abnormality (step ST11).

[0070] If there is no abnormality (step ST11: NO), the ECU sets the diagnostic conditions for diagnostic item 6 and acquires the capacitor voltage of capacitor C1 (step ST12). The diagnosis for diagnostic item 6 is performed under normal conditions, taking time for the capacitor voltage of capacitor C1 to rise from approximately 24V to approximately 48V. Next, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 48V), that is, whether there is an abnormality (step ST13).

[0071] If there is no abnormality (step ST13: NO), the ECU sets the diagnostic conditions for diagnostic item 7 and acquires the capacitor voltage of capacitor C1 (step ST14). The diagnosis for diagnostic item 7 takes time for the capacitor voltage of capacitor C1 to rise from approximately 48V to approximately 96V under normal conditions. Next, the ECU determines whether the capacitor voltage of capacitor C1 is within a predetermined range (for example, approximately 96V), that is, whether there is an abnormality (step ST15).

[0072] In steps ST3, 5, 7, 9, 11, 13, and 15, if an abnormality is detected (steps ST3, 5, 7, 9, 11, 13, and 15: YES), the ECU performs a fail-safe process (step ST18). Fail-safe processes include warning the user about a battery BT that is unusable due to an abnormality, and stopping the power supply from the battery BT.

[0073] If no abnormality is found after step ST15 (step ST15: NO), the ECU sets the discharge of the first battery BT1 and the second battery BT2 to be enabled (step ST19). Since the operation of steps ST1 to ST15 diagnoses that switches S1, S2, and S3 are not stuck, the first battery BT1 and the second battery BT2 can be used in any configuration: single-unit connection, series connection, or parallel connection.

[0074] Next, the ECU determines whether or not to use the first battery BT1 and the second battery BT2 in series connection (step ST20). How the first battery BT1 and the second battery BT2 are used is predetermined by the user when the power supply device 5 is started.

[0075] If the ECU determines that the first battery BT1 and the second battery BT2 are not to be used in series (step ST20: NO), it controls the discharge of capacitor C1 to 48V (step ST21). The electromotive force of the first battery BT1 and the second battery BT2 is 48V each, and when they are used individually or in parallel, the ECU discharges capacitor C1 until the capacitor voltage matches the electromotive force.

[0076] Next, the ECU discharges at least one of the first battery BT1 and the second battery BT2 according to a pre-selected mode (step ST22).

[0077] The discharge of capacitor C1 is performed by the ECU turning off the first switch S1, the second switch S2, and the third switch S3, and turning on the discharge switch S4. The discharge of capacitor C1 corresponds to discharge mode Co4 shown in Figure 7.

[0078] [3. Effects] As described above, the power supply device 5 in this embodiment is a power supply device 5 comprising an inverter 51, a first battery BT1 and a second battery BT2 that supply power to the inverter 51, and a capacitor C1 provided on the inverter 51 and connected to at least one of the first battery BT1 and the second battery BT2. The power supply device 5 includes: a first switch S1 positioned between the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2, which switches the connection state between the negative terminal of the first battery BT1 and the positive terminal of the second battery BT2 between a conduction state and a disconnection state; a second switch S2 positioned between one terminal of the capacitor C1 and the positive terminal of the second battery BT2, which switches the connection state between one terminal of the capacitor C1 and the positive terminal of the second battery BT2 between a conduction state and a disconnection state; a third switch S3 positioned between the other terminal of the capacitor C1 and the negative terminal of the first battery BT1, which switches the connection state between the other terminal of the capacitor C1 and the negative terminal of the first battery BT1 between a conduction state and a disconnection state; a voltage measuring instrument 30 for measuring the capacitor voltage, which is the voltage of the capacitor C1; and an ECU that controls the connection states of the first switch S1, the second switch S2, and the third switch S3, and controls the output state of power from the first battery BT1 or the second battery BT2. When a trigger occurs to start the inverter 51, the ECU sets the first switch S1, the second switch S2, and the third switch S3 to an off state and outputs power from at least one of the first battery BT1 and the second battery BT2. Based on the capacitor voltage in this state, the ECU performs a continuity fixation diagnosis to determine whether at least one of the first switch S1, the second switch S2, and the third switch S3 is stuck in a conductive state. After the continuity fixation diagnosis, the ECU sets the first switch S1, the second switch S2, and the third switch S3 to an on state and outputs power from at least one of the first battery BT1 and the second battery BT2. Based on the capacitor voltage in this state, the ECU performs a disconnection fixation diagnosis to determine whether at least one of the first switch S1, the second switch S2, and the third switch S3 is stuck in an off state.

[0079] With this configuration, since the first switch S1, second switch S2, and third switch S3 are checked for sticking at once, it is not necessary to check for sticking each time the connection state of the two batteries BT is switched, thus enabling a quick switch of the connection state of the two batteries BT. Therefore, the time required for checking for sticking of the first switch S1, second switch S2, and third switch S3 that switch the connection state of the batteries BT, and for precharging the capacitor C1, can be reduced, improving convenience.

[0080] Furthermore, the switch lock-up diagnosis involves setting the ECU to a state where only the third switch S3 out of the first switch S1, second switch S2, and third switch S3 is in a conductive state, and outputting power from the first battery BT1. Based on the capacitor voltage in this state, the diagnosis determines whether the third switch S3 is locked in a closed state. This includes a second switch disconnection / sticking diagnosis that diagnoses whether the second switch S2 is stuck in the disconnected state based on the capacitor voltage when the system is set to a state where the switches are connected, and a first switch disconnection / sticking diagnosis that diagnoses whether the first switch S1 is stuck in the disconnected state based on the capacitor voltage when the ECU is set to a state where only the first switch S1 among the first switch S1, second switch S2, and third switch S3 is connected, and power is output from the first battery BT1 and the second battery BT2.

[0081] This configuration allows for a proper diagnosis of whether or not the first switch S1, the second switch S2, and the third switch S3 are stuck in an interrupted state.

[0082] Furthermore, the ECU performs a diagnosis of the first switch lock after diagnosing the third switch lock or diagnosing the second switch lock.

[0083] With this configuration, the capacitor voltage of capacitor C1 can be gradually increased, eliminating the need for a procedure to lower the voltage from high to low. This reduces the time required to diagnose whether there is any sticking in the conduction or disconnection state of the first switch S1, the second switch S2, and the third switch S3.

[0084] Furthermore, the ECU performs a first switch lockout diagnosis after the third switch lockout diagnosis and the second switch lockout diagnosis, and performs either the third switch lockout diagnosis or the second switch lockout diagnosis first. When performing the diagnosis of the other switch, if the capacitor voltage reaches a predetermined voltage lower than the output voltage of the first battery BT1 or the second battery BT2, the ECU switches from the diagnosis of the first switch lockout diagnosis to the diagnosis of the other switch lockout diagnosis of the second switch lockout diagnosis.

[0085] With this configuration, when performing one diagnosis, the process can be moved to the other diagnosis before the capacitor voltage of capacitor C1 reaches the electromotive force of battery BT. This reduces the time required to diagnose whether there is any sticking in the conduction or disconnection state of the first switch S1, the second switch S2, and the third switch S3.

[0086] Furthermore, the continuity fixation diagnosis includes a third switch continuity fixation diagnosis, which diagnoses whether the third switch S3 is stuck in a continuity state based on the capacitor voltage when the ECU is set to output power from the first battery BT1 with the first switch S1, second switch S2, and third switch S3 all in the off state, and when the ECU is set to output power from the second battery BT2. This includes a second switch continuity fixation diagnosis that diagnoses whether the second switch S2 is stuck in a conductive state based on the capacitor voltage when the ECU is set to a state where all of the first switch S1, second switch S2, and third switch S3 are in an off state, and the first battery BT1 and second battery BT2 are outputting power, based on the capacitor voltage when the ECU is set to that state.

[0087] This configuration allows for a proper diagnosis of whether or not there is any sticking that causes the first switch S1, the second switch S2, and the third switch S3 to remain in a conductive state.

[0088] Furthermore, when the first battery BT1 and the second battery BT2 are connected in series to the PCU51, the ECU does not perform discharge control to reduce the capacitor voltage after the continuity lock diagnosis and the disconnection lock diagnosis are completed.

[0089] With this configuration, if the first battery BT1 and the second battery BT2 are connected in series after diagnosis by the ECU, the power supply device 5 can be driven while the capacitor C1 is still pre-charged.

[0090] Furthermore, if the first battery BT1 and the second battery BT2 are connected in parallel to the PCU 51, or if only one of the first battery BT1 or the second battery BT2 is connected, the ECU performs discharge control to reduce the capacitor voltage to the electromotive force of the first battery BT1 and the second battery BT2 connected to the PCU 51 after the continuity lock diagnosis and the disconnection lock diagnosis are completed.

[0091] With this configuration, after diagnosis by the ECU, the capacitor voltage can be appropriately reduced when using the first battery BT1 and the second battery BT2 in parallel connection, or when using either the first battery BT1 or the second battery BT2.

[0092] (Other embodiments) The embodiments described above represent only one aspect of the present invention and can be modified and applied as needed without departing from the spirit of the invention.

[0093] In the embodiment described above, the third switch continuity fixation diagnosis, the second switch continuity fixation diagnosis, and the first switch continuity fixation diagnosis are performed in this order, but the invention is not limited to this order and may be performed in any order. In the embodiment described above, the third switch shutdown fixation diagnosis, the second switch shutdown fixation diagnosis, and the first switch shutdown fixation diagnosis are performed in this order, but the invention is not limited to this, and the second switch shutdown fixation diagnosis, the third switch shutdown fixation diagnosis, and the first switch shutdown fixation diagnosis may also be performed in this order.

[0094] In other embodiments, the ECU performs only a second switch disconnection fixation diagnosis if the first battery BT1 is not connected, and performs only a third switch disconnection fixation diagnosis if the second battery BT2 is not connected.

[0095] With this configuration, if the first battery BT1 is not connected, the third switch shutdown sticking diagnosis and the first switch shutdown sticking diagnosis are not performed, and if the second battery BT2 is not connected, the second switch shutdown sticking diagnosis and the first switch shutdown sticking diagnosis are not performed, thus shortening the diagnostic time after the PCU51 is started.

[0096] In other embodiments, the continuity fixation diagnosis includes a third switch continuity fixation diagnosis, which diagnoses whether the third switch S3 is stuck in a continuity state based on the capacitor voltage when the first battery BT1 is outputting power with all three switches S1, S2, and S3 in an off state; a second switch S2 continuity fixation diagnosis, which diagnoses whether the second switch S2 is stuck in a continuity state based on the capacitor voltage when the second battery BT2 is outputting power; and a first switch continuity fixation diagnosis, which diagnoses whether the first switch S1 is stuck in a continuity state based on the capacitor voltage when the first battery BT1 and the second battery BT2 are outputting power. The ECU performs only the second switch continuity fixation diagnosis if the first battery BT1 is not connected, and only the third switch continuity fixation diagnosis if the second battery BT2 is not connected.

[0097] With this configuration, if the first battery BT1 is not connected, the third switch continuity sticking diagnosis and the first switch continuity sticking diagnosis are not performed, and if the second battery BT2 is not connected, the second switch continuity sticking diagnosis and the first switch continuity sticking diagnosis are not performed, thus shortening the diagnostic time after the PCU51 is started.

[0098] The case in which the first battery BT1 or the second battery BT2 is not connected includes, for example, cases where the power supply device 5 does not have a battery installed, or where the power supply device 5 has a battery installed, but the battery BT is not electrically connected to the power supply device 5 for reasons such as the battery BT being faulty and unable to output power.

[0099] The processor 511 may consist of multiple processors or a single processor. The processor 511 may also be hardware programmed to implement the functions described above. In this case, these processors may consist of, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0100] Furthermore, the operation steps shown in Figures 9 and 10 are divided according to the main processing content, and the present invention is not limited by the way the processing units are divided or their names. Depending on the processing content, it may be further divided into more steps. Alternatively, it may be divided so that one step unit includes even more processing. Also, the order of the steps may be rearranged as appropriate, as long as it does not impede the spirit of the present invention.

[0101] [4. Configurations supported by the above embodiment] The above embodiment supports the following configuration.

[0102] (Composition 1) A power supply device comprising an inverter, a first battery and a second battery that supply power to the inverter, and a capacitor provided on the inverter and connected to at least one of the first battery and the second battery, comprising: a first switch positioned between the negative electrode of the first battery and the positive electrode of the second battery, which switches the connection state between the negative electrode of the first battery and the positive electrode of the second battery between a conduction state and a disconnection state; a second switch positioned between one terminal of the capacitor and the positive electrode of the second battery, which switches the connection state between the one terminal of the capacitor and the positive electrode of the second battery between a conduction state and a disconnection state; a third switch positioned between the other terminal of the capacitor and the negative electrode of the first battery, which switches the connection state between the other terminal of the capacitor and the negative electrode of the first battery between a conduction state and a disconnection state; a voltage measuring instrument for measuring the capacitor voltage, which is the voltage of the capacitor; and a control for the connection states of the first switch, the second switch and the third switch, and the first battery or the second A power supply device comprising: a control unit for controlling the output state of power from a battery, wherein when a trigger for starting the inverter occurs, the control unit sets the first switch, the second switch, and the third switch to an off state and sets the device to output power from at least one of the first battery and the second battery, and performs a continuity lock diagnosis to diagnose whether at least one of the first switch, the second switch, and the third switch is stuck in a conductive state based on the capacitor voltage in that state, and after the continuity lock diagnosis, sets the first switch, the second switch, and the third switch to an open state and sets the device to output power from at least one of the first battery and the second battery, and performs an off-lock lock diagnosis to diagnose whether at least one of the first switch, the second switch, and the third switch is stuck in an off state based on the capacitor voltage in that state. With this configuration, since the first, second, and third switches are checked for sticking at once, it is not necessary to check for sticking each time the connection state of the two batteries is switched, allowing for a quick switch between the two battery connections. Therefore, the time required for checking for sticking of the first, second, and third switches that switch the battery connection state, and for precharging the capacitors, can be reduced, improving convenience.

[0103] (Configuration 2) The power supply device according to Configuration 1, characterized in that the interruption sticking diagnosis includes: a third switch interruption sticking diagnosis, which diagnoses whether the third switch is stuck in the interrupted state based on the capacitor voltage when the control unit is set to a state in which only the third switch among the first switch, the second switch, and the third switch is in a conductive state and the first battery is outputting power; a second switch interruption sticking diagnosis, which diagnoses whether the second switch is stuck in the interrupted state based on the capacitor voltage when the control unit is set to a state in which only the second switch among the first switch, the second switch, and the third switch is in a conductive state and the second battery is outputting power; and a first switch interruption sticking diagnosis, which diagnoses whether the first switch is stuck in the interrupted state based on the capacitor voltage when the control unit is set to a state in which only the first switch among the first switch, the second switch, and the third switch is in a conductive state and the first battery and the second battery are outputting power. This configuration allows for a proper diagnosis of whether or not the first switch, the second switch, and the third switch are stuck in the off state.

[0104] (Composition 3) The power supply device according to configuration 2, characterized in that the control unit performs the first switch shut-off fixation diagnosis after the third switch shut-off fixation diagnosis or the second switch shut-off fixation diagnosis. This configuration allows the capacitor voltage to be gradually increased, eliminating the need for a procedure to lower the voltage from high to low. This reduces the time required to diagnose whether the first, second, and third switches are stuck in either a conductive or disconnected state.

[0105] (Composition 4) The power supply device according to configuration 2, characterized in that the control unit performs the first switch disconnection fixation diagnosis after the third switch disconnection fixation diagnosis and the second switch disconnection fixation diagnosis, performs one of the third switch disconnection fixation diagnosis or the second switch disconnection fixation diagnosis first, and when performing the one diagnosis, if the capacitor voltage reaches a predetermined voltage lower than the output voltage of the first battery or the second battery, it transitions from the one diagnosis to the other diagnosis of the third switch disconnection fixation diagnosis or the second switch disconnection fixation diagnosis. With this configuration, when performing one diagnosis, it is possible to move on to the other diagnosis before the capacitor voltage of the capacitor reaches the electromotive force of the battery, thus shortening the time required to diagnose whether there is any sticking in the conduction or disconnection state of the first switch, the second switch, and the third switch.

[0106] (Composition 5) The power supply device according to configurations 2 to 5, characterized in that the control unit performs only the second switch disconnection fixation diagnosis when the first battery is not connected, and performs only the third switch disconnection fixation diagnosis when the second battery is not connected. With this configuration, if the first battery is not connected, the third switch shutdown lockout diagnosis and the first switch shutdown lockout diagnosis are not performed, and if the second battery is not connected, the second switch shutdown lockout diagnosis and the first switch shutdown lockout diagnosis are not performed, thus shortening the diagnostic time after the inverter is started.

[0107] (Composition 6) The power supply device according to any one of configurations 1 to 5, characterized in that the continuity fixation diagnosis includes: a third switch continuity fixation diagnosis, which diagnoses whether the third switch is stuck in a continuity state based on the capacitor voltage when the control unit is set to output power from the first battery with all three switches (first, second, and third) in an off state; a second switch continuity fixation diagnosis, which diagnoses whether the second switch is stuck in a continuity state based on the capacitor voltage when the control unit is set to output power from the second battery; and a first switch continuity fixation diagnosis, which diagnoses whether the first switch is stuck in a continuity state based on the capacitor voltage when the control unit is set to output power from both the first and second batteries. This configuration allows for a proper diagnosis of whether or not there is any sticking that causes the first switch, the second switch, and the third switch to remain in a conductive state.

[0108] (Composition 7) The power supply device according to configuration 6, characterized in that the control unit performs only the second switch continuity lock diagnosis when the first battery is not connected, and performs only the third switch continuity lock diagnosis when the second battery is not connected. With this configuration, if the first battery is not connected, the third switch continuity lock diagnosis and the first switch continuity lock diagnosis are not performed, and if the second battery is not connected, the second switch continuity lock diagnosis and the first switch continuity lock diagnosis are not performed, thus shortening the diagnostic time after the inverter is started.

[0109] (Composition 8) The power supply device according to any one of configurations 1 to 7, characterized in that when the first battery and the second battery are connected in series with respect to the inverter, the control unit does not perform discharge control to reduce the capacitor voltage after the completion of the continuity lock diagnosis and the disconnection lock diagnosis. With this configuration, if the first battery and the second battery are connected in series after diagnosis by the control unit, the power supply device can be driven while the capacitor is still pre-charged.

[0110] (Composition 9) The power supply device according to any one of configurations 1 to 7, characterized in that, when the first battery and the second battery are connected in parallel to the inverter, or when only one of the first battery or the second battery is connected, the control unit performs discharge control to reduce the capacitor voltage to the electromotive force of the first battery and the second battery connected to the inverter after the completion of the continuity lock diagnosis and the disconnection lock diagnosis. With this configuration, after diagnosis by the control unit, the capacitor voltage can be appropriately reduced when the first battery and the second battery are used in parallel connection, or when either the first battery or the second battery is used. [Explanation of Symbols]

[0111] 1. Motorcycle 2-bar handlebars 3 Front wheels 4 Rear wheels 5 Power supply device 6 Front Fork 7 Rear cushion 11. Steering Stem 12 Headpipe 13 Upper Frame 14 Lower Frame 15 Seat Frame 16 Middle Frame 17 Support Frame 20 Swingarm 30 Voltage Measuring Instruments 40 Fender support arm 51 PCU (Inverter) 60 Switching section 64 Battery storage device 70 Battery Unit 71 Discharge switch section 72 Charging switch section 73 Precharge switch section 74 Discharge switch 76 Charging Switch 77 Diodes 78 Precharge switch 79 Diodes 80R Precharge Resistor 80r battery resistance 511 processors 512 memory BT Battery BT1 Battery 1 BT2 Second Battery C1 Capacitor MT Motor S1 1st Switch S2 Second Switch S3 3rd switch S4 Discharge Switch

Claims

1. Inverter (51), A first battery (BT1) and a second battery (BT2) supply power to the inverter (51), A capacitor (C1) is provided in the inverter (51) and connected to at least one of the first battery (BT1) and the second battery (BT2), A power supply device (5) comprising, A first switch (S1) is positioned between the negative terminal of the first battery (BT1) and the positive terminal of the second battery (BT2), and switches the connection state between the negative terminal of the first battery (BT1) and the positive terminal of the second battery (BT2) between a conductive state and a disconnected state. A second switch (S2) is positioned between one terminal of the capacitor (C1) and the positive terminal of the second battery (BT2), and switches the connection state between the one terminal of the capacitor (C1) and the positive terminal of the second battery (BT2) between a conductive state and a disconnected state. A third switch (S3) is positioned between the other terminal of the capacitor (C1) and the negative terminal of the first battery (BT1), and switches the connection state between the other terminal of the capacitor (C1) and the negative terminal of the first battery (BT1) between a conductive state and a disconnected state. A voltage measuring instrument (30) for measuring the capacitor voltage, which is the voltage across the capacitor (C1), The system includes a control unit that controls the connection state of the first switch (S1), the second switch (S2), and the third switch (S3), and controls the output state of power from the first battery (BT1) or the second battery (BT2), When a trigger for starting the inverter (51) occurs, the control unit sets the first switch (S1), the second switch (S2), and the third switch (S3) to an off state, and sets the control unit to output power from at least one of the first battery (BT1) and the second battery (BT2). Based on the capacitor voltage in this state, the control unit performs a continuity fixation diagnosis to determine whether at least one of the first switch (S1), the second switch (S2), and the third switch (S3) is stuck in a conductive state. After the continuity fixation diagnosis, the capacitor voltage is set to a state where at least one of the first switch (S1), the second switch (S2), and the third switch (S3) is in a continuity state, and at least one of the first battery (BT1) and the second battery (BT2) is outputting power. Based on this, a break-off fixation diagnosis is performed to determine whether at least one of the first switch (S1), the second switch (S2), and the third switch (S3) is stuck in a break-off state. A power supply device characterized by the following features.

2. The aforementioned blockage fixation diagnosis is, When the control unit is set to conduct only the third switch (S3) among the first switch (S1), the second switch (S2), and the third switch (S3), and is set to output power from the first battery (BT1), a third switch interruption / sticking diagnosis is performed to diagnose whether the third switch (S3) is stuck in the interrupted state based on the capacitor voltage in this state, The control unit is set to conduct only the second switch (S2) among the first switch (S1), the second switch (S2), and the third switch (S3), and the second battery (BT2) is outputting power. Based on the capacitor voltage in this state, the second switch blockage fixation diagnosis diagnoses whether the second switch (S2) is stuck in the blocked state. The control unit is set to conduct only the first switch (S1) among the first switch (S1), the second switch (S2), and the third switch (S3), and is set to output power from the first battery (BT1) and the second battery (BT2). Based on the capacitor voltage in this state, a first switch interruption / sticking diagnosis is performed to diagnose whether the first switch (S1) is stuck in the interrupted state. including, The power supply device according to feature 1.

3. The control unit, The first switch shut-off and sticking diagnosis is performed after the third switch shut-off and sticking diagnosis or the second switch shut-off and sticking diagnosis. The power supply device according to feature 2.

4. The control unit, After the third switch shutdown lock diagnosis and the second switch shutdown lock diagnosis, the first switch shutdown lock diagnosis is performed. The system first performs either the third switch lockout diagnosis or the second switch lockout diagnosis. If, during the first diagnosis, the capacitor voltage reaches a predetermined voltage lower than the output voltage of the first battery (BT1) or the second battery (BT2), the system transitions from the first diagnosis to the other diagnosis of the third switch lockout diagnosis or the second switch lockout diagnosis. The power supply device according to feature 2.

5. The control unit, If the first battery (BT1) is not connected, only the second switch disconnection fixation diagnosis is performed. If the second battery (BT2) is not connected, only the diagnosis of the third switch being stuck is performed. The power supply device according to feature 2.

6. The aforementioned continuity fixation diagnosis is performed by The control unit is set to output power from the first battery (BT1) while the first switch (S1), the second switch (S2), and the third switch (S3) are all in the off state. Based on the capacitor voltage in this state, a third switch continuity fixation diagnosis is performed to determine whether the third switch (S3) is stuck in a conductive state. The control unit is set to output power from the second battery (BT2), and based on the capacitor voltage, the second switch (S2) is diagnosed as being stuck in a conductive state, and the second switch continuity fixation diagnosis is performed. Based on the capacitor voltage when the control unit is set to output power from the first battery (BT1) and the second battery (BT2), a first switch continuity fixation diagnosis is performed to diagnose whether the first switch (S1) is stuck in a conductive state, including, The power supply device according to feature 1.

7. The control unit, If the first battery (BT1) is not connected, only the second switch continuity fixation diagnosis is performed. If the second battery (BT2) is not connected, only the third switch continuity lock diagnosis is performed. The power supply device according to feature 6.

8. The control unit, When the first battery (BT1) and the second battery (BT2) are connected in series to the inverter (51), discharge control to reduce the capacitor voltage is not performed after the continuity lock diagnosis and the disconnection lock diagnosis are completed. A power supply device according to any one of claims 1 to 7.

9. The control unit, When the first battery (BT1) and the second battery (BT2) are connected in parallel to the inverter (51), or when only one of the first battery (BT1) or the second battery (BT2) is connected, after the continuity lock diagnosis and the disconnection lock diagnosis are completed, discharge control is performed to reduce the capacitor voltage to the electromotive force of the first battery (BT1) and the second battery (BT2) connected to the inverter (51). A power supply device according to any one of claims 1 to 7.

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