Power supply device

Abstract

A battery module failure is reliably determined. A power supply device is provided with: a plurality of battery modules (2) including a failure determination section (21) that determines failure and normality and outputs failure and normality using signals of "high" and "low"; a failure transmission line (3) connected to the failure determination section (21) of each battery module (2); and a module failure determination circuit (1) connected to the failure transmission line (3) and determining failure and normality of the battery modules (2). The module failure determination circuit (1) is provided with: a voltage determination circuit (4) that determines "high" and "low" of the failure transmission line (3); an impedance detection circuit (5) that detects impedance with respect to a ground line (23); and an arithmetic circuit (6) that determines failure and normality of the battery modules (2) and abnormality of the failure transmission line (3) based on outputs of the voltage determination circuit (4) and the impedance detection circuit (5).

Description

Technical Field

[0001] This invention relates to a power supply device having multiple battery modules, and more particularly to a power supply device that transmits the fault and normal operation of each battery module to a module fault determination circuit via a fault transmission line. Background Technology

[0002] Power supply devices with multiple battery modules can increase the number of battery modules and thus increase the charging and discharging capacity, resulting in a large output. Therefore, they are used in power supply devices such as electric vehicles and energy storage devices. This power supply device detects faults in each battery module to ensure stable operation (see Patent Document 1).

[0003] The power supply unit described above has a fault determination unit in each battery module to determine whether it is faulty or normal. Each battery module connects the fault determination unit to the fault transmission line and to the module fault determination circuit that determines the fault and normal status of all battery modules, thereby enabling the monitoring of the status of all battery modules.

[0004] Prior art literature

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-087129 Summary of the Invention

[0007] -The problem the invention aims to solve-

[0008] The power supply unit utilizes a module fault detection circuit to determine the faults of individual battery modules. This power supply unit connects the fault detection section of each battery module to a fault transmission line, thereby detecting which battery module has failed. In this power supply unit, the fault detection section of each battery module connected to the fault transmission line outputs a "high" signal in a normal state and a "low" signal in a fault state. The module fault detection circuit determines all battery modules as normal when the fault transmission line is "high" and determines that a specific battery module has failed when the fault transmission line is "low". However, a power supply unit that determines faults and normal operation solely based on the "high" and "low" signals of the fault transmission line cannot accurately determine the faults and normal operation of battery modules when the fault transmission line is not in an abnormal state, such as poor contact or a broken wire. Therefore, a power supply unit that relies solely on "high" and "low" signals to determine battery module faults can never accurately determine the faults and normal operation of battery modules.

[0009] This invention was developed with the aim of further eliminating the above-mentioned disadvantages. One of the objectives of this invention is to provide a power supply device that can reliably determine the fault of a battery module.

[0010] -Methods for solving problems-

[0011] A power supply device according to a certain aspect of the present invention includes: multiple battery modules, each including a fault determination unit that determines whether a battery module is faulty or normal and outputs fault and normal status using "high" and "low" signals; a fault transmission line connected to the fault determination unit of each battery module; and a module fault determination circuit connected to the fault transmission line for determining whether a battery module is faulty or normal. The module fault determination circuit includes: a voltage determination circuit for determining the "high" and "low" values ​​of the fault transmission line; an impedance detection circuit for detecting the impedance corresponding to the ground wire; and an arithmetic circuit for determining whether the battery module is faulty or normal and whether the fault transmission line is abnormal based on the outputs of the voltage determination circuit and the impedance detection circuit.

[0012] -Invention Effects-

[0013] The above power supply device has the advantage of being able to detect battery module faults more reliably. Attached Figure Description

[0014] Figure 1 This is a block diagram of a power supply device according to an embodiment of the present invention. Detailed Implementation

[0015] The present invention will now be described in detail with reference to the accompanying drawings. Furthermore, in the following description, terms indicating specific directions or positions (e.g., "upper," "lower," and other terms including these terms) are used as needed; however, the use of these terms is to facilitate understanding of the invention with reference to the accompanying drawings and is not intended to limit the technical scope of the invention using the meaning of these terms. Additionally, the same symbols appearing in multiple figures represent the same or equivalent parts or components.

[0016] Furthermore, the embodiments shown below represent specific examples of the technical concept of the present invention and do not limit the present invention. In addition, unless specifically stated otherwise, the dimensions, materials, shapes, and relative arrangements of the constituent components described below are not intended to limit the scope of the present invention, but are merely illustrative. Furthermore, the content described in one embodiment or example can be applied to other embodiments or examples. Also, the size and positional relationships of the components shown in the accompanying drawings may sometimes be exaggerated for clarity.

[0017] The power supply device according to the first embodiment of the present invention includes: a plurality of battery modules including a fault determination unit, which determines whether a battery module is faulty or normal and outputs fault and normal status using "high" and "low" signals; a fault transmission line connected to the fault determination unit of each battery module; and a module fault determination circuit connected to the fault transmission line, which determines whether a battery module is faulty or normal. The module fault determination circuit includes: a voltage determination circuit that determines whether the fault transmission line is "high" or "low"; an impedance detection circuit that detects the impedance relative to ground; and an arithmetic circuit that determines whether a battery module is faulty or normal and whether the fault transmission line is abnormal based on the outputs of the voltage determination circuit and the impedance detection circuit.

[0018] The power supply device described above has the advantage of more reliably detecting battery module faults. In particular, it can reliably detect whether the battery module is faulty or normal, as well as abnormalities in the fault transmission line. This is because, in the power supply device described above, the arithmetic circuit determines whether the battery module is faulty or normal, as well as abnormalities in the fault transmission line, based on the outputs of the voltage determination circuit that determines whether the fault transmission line is "high" or "low" and the impedance detection circuit that detects the impedance relative to the ground line.

[0019] The power supply device according to the second embodiment of the present invention includes: a pull-up power supply connected to the terminal of the fault transmission line via a pull-up resistor to pull up the voltage of the fault transmission line to "high"; and a fault determination unit including a short-circuit switch that connects the fault transmission line to ground and sets it to "low" based on either fault or normal conditions.

[0020] In the third embodiment of the present invention, when the fault determination unit determines the fault of the battery module, the power supply device sets the short-circuit switch to the on state, connects the fault transmission line to the ground wire and sets it to "low".

[0021] The power supply device according to the fourth embodiment of the present invention includes: a voltage determination circuit having a first switching element that becomes on when detecting a "low" state of a faulty transmission line and becomes off when detecting a "high" state of the faulty transmission line and a high impedance higher than a set impedance; and an impedance detection circuit having a second switching element that becomes on when detecting a "high" state of a faulty transmission line and switches to off when detecting a "low" state of a faulty transmission line and a high impedance higher than a set impedance. The power supply device's operational circuit determines the battery module to be normal when the first switching element is off and the second switching element is on, determines the battery module to be abnormal when the first switching element is on and the second switching element is off, and determines the faulty transmission line to be abnormal when both the first and second switching elements are off.

[0022] The power supply device described above has the advantage of being able to easily and reliably detect battery module faults and fault transmission line abnormalities because the operational circuit determines the on and off states of the first switching element of the voltage determination circuit and the second switching element of the impedance detection circuit.

[0023] In the power supply device of the fifth embodiment of the present invention, the first switching element is a p-channel FET. The FET has its drain as the output, its source connected to the power supply, its gate connected to the power supply via an input resistor, and its gate connected to the fault transmission line via a diode. The diode is connected in the positive direction to the current flowing from the gate side to the fault transmission line.

[0024] In the power supply device of the sixth embodiment of the present invention, the second switching element is an n-channel FET. The FET has its source as the output, its gate connected to ground via an input resistor and connected to the fault transmission line via a Zener diode. The Zener diode is configured to direct the current flowing from the gate to the fault transmission line in the positive direction. The voltage obtained by subtracting the Zener voltage from the "high" level voltage of the fault transmission line is input to the gate, thereby setting the Zener voltage to the voltage that enables the FET to conduct.

[0025] (Implementation Method 1)

[0026] Figure 1 The power supply device 100 includes: multiple battery modules 2; a fault transmission line 3 connected to each battery module 2; and a module fault determination circuit 1 that determines whether the battery module 2 is faulty or normal based on the "high" or "low" of the fault transmission line 3, and further determines the abnormality of the fault transmission line 3 based on the impedance of the fault transmission line 3.

[0027] (Battery Module 2)

[0028] Battery module 2 contains multiple rechargeable battery cells (not shown) and a circuit board (not shown) for installing protection circuits that detect the voltage and remaining capacity of the battery cells. Battery module 2 includes a fault determination unit 21 that determines whether the battery is in a normal state or has malfunctioned. The fault determination unit 21 detects faults in the battery cells, circuit board, etc., and sets the connection terminal 22 of the fault transmission line 3 to "high" or "low". The fault determination unit 21 connects a short-circuit switch 24 between the connection terminal 22 and the ground wire 23. The short-circuit switch 24 can use semiconductor switching elements such as FETs and transistors, but... Figure 1 The fault determination unit 21 sets the short-circuit switch 24 as FET24A. When the fault is determined, it inputs a conduction voltage to the gate to switch FET24A to the conduction state. In the normal state, it sets the gate voltage of FET24A to the cutoff voltage to set FET24A to the cutoff state.

[0029] (Faulty transmission line 3)

[0030] The fault transmission line 3 is connected to the positive side of the pull-up power supply 10 via the pull-up resistor 25 at the terminal. When the short-circuit switch 24 is off, the connection terminal 22 of the fault transmission line 3 becomes "high". Figure 1 The power supply unit 100 sets up a pull-up power supply 10 in the module fault determination circuit 1, and connects it to the terminal of the fault transmission line 3 via the power line 9 and the pull-up resistor 25. The power supply unit 100 does not specify the voltage of the pull-up power supply 10, but sets it to, for example, 12V.

[0031] In the normal state, the FET24A of the short-circuit switch 24 in the fault determination unit 21 of battery module 2 is in the off state, so the connection terminal 22 is set to a "high" level when battery module 2 is in a normal state. In the fault state of battery module 2, the FET24A of the short-circuit switch 24 is switched to the on state, so when the fault determination unit 21 determines that there is a fault, the connection terminal 22 is connected to the ground line 23 through the FET24A of the short-circuit switch 24, thereby becoming a "low" level.

[0032] Each battery module 2 connects its fault detection unit 21 to the fault transmission line 3 via its connection terminal 22. Therefore, if the fault detection unit 21 of any battery module 2 detects a fault and switches the short-circuit switch 24 to the ON state, the fault transmission line 3 becomes "low" level via the ON short-circuit switch 24 and is connected to the ground line 23. When all battery modules 2 are operating normally, the short-circuit switches 24 of all battery modules 2 are kept in the OFF state, and the fault transmission line 3 is kept in the "high" state.

[0033] (Module Fault Detection Circuit 1)

[0034] The module fault determination circuit 1 includes: a voltage determination circuit 4, which determines whether the fault transmission line 3 is "high" or "low"; an impedance detection circuit 5, which detects the impedance of the fault transmission line 3 relative to the ground line 23; and an arithmetic circuit 6, which determines whether the battery module 2 is faulty or normal and whether the fault transmission line 3 is abnormal based on the outputs of the voltage determination circuit 4 and the impedance detection circuit 5.

[0035] (Voltage determination circuit 4)

[0036] Voltage determination circuit 4 detects the voltage of fault transmission line 3 to determine whether each battery module 2 is faulty or normal. Voltage determination circuit 4 includes a first switching element 11, which is turned on when the fault transmission line 3 is in a "low" state and turned off when it is in a "high" state. The first switching element 11 is a p-channel FET 11A. This FET 11A has its drain connected to the operational circuit 6 as the output side, its source connected to the power supply 13, its gate connected to the power supply 13 via input resistor 14, and its gate connected to the fault transmission line 3 via diode 15. Diode 15 is connected in the forward direction to allow current flowing from the gate side to the fault transmission line 3.

[0037] The voltage determination circuit 4 described above operates on the condition that the voltage of the fault transmission line 3 is at a "high" level and no current flows through the diode 15, causing the gate of the p-channel FET 11A to be connected to the source and thus in a cutoff state. If the fault transmission line 3 becomes "low" level, the fault transmission line 3 is energized from the power supply 13 through the input resistor 14 and the forward-biased diode 15, providing a negative on-state voltage to the gate of the FET 11A relative to the power supply 13, thus turning the FET 11A on. Furthermore, since the fault transmission line 3 becomes high impedance under abnormal conditions, it is impossible to energize the high-impedance fault transmission line 3 from the power supply 13 along the forward direction of the diode 15, causing the gate of the FET 11A to become "high" and the FET 11A to become cutoff. This voltage determination circuit 4 only turns on the FET 11A of the first switching element 11 when any one of the battery modules 2 has failed, outputting a "high" signal from the drain of the FET to the operational circuit 6. When all battery modules 2 are in a normal state, or when the fault transmission line 3 is in an abnormal state, the FET11A of the first switching element 11 becomes cut off and does not output "high".

[0038] (Impedance detection circuit 5)

[0039] The impedance detection circuit 5 includes a second switching element 12. The second switching element 12 is switched on when it detects a "high" level on the fault transmission line 3, and switched off when it detects a "low" level and high impedance on the fault transmission line 3. The second switching element 12 performing these operations is an n-channel FET 12A. This FET 12A has its drain connected to the power supply 16 as its input side and its source connected to the operational circuit 6 as its output side. Its gate is connected to ground 19 via an input resistor 17 and to the fault transmission line 3 via a Zener diode 18. The Zener diode 18 directs the current flowing from the gate to the fault transmission line 3 in the forward direction, setting the FET 12A to the off state based on the "low" level of the fault transmission line 3. Furthermore, the voltage obtained by subtracting the Zener voltage from the "high" level voltage of the fault transmission line 3 is input to the gate of the FET 12A, thereby setting the Zener voltage of the Zener diode 18 to the voltage that turns the FET 12A on. Furthermore, the Zener voltage of the Zener diode 18 is set to be higher than the voltage input from the power supply 13 of the voltage determination circuit 4 via the forward-biased diode 15 when the fault transmission line 3 is at high impedance.

[0040] When the fault transmission line 3 is at a "high" level, the impedance detection circuit 5 inputs a conduction voltage to the gate of FET12A via Zener diode 18, thus turning FET12A on. When the fault transmission line 3 is at a "low" level, the gate is connected to ground 23 via Zener diode 18 and input resistor 17, and the gate voltage of FET12A becomes the cutoff voltage, thus turning it off. Furthermore, if the fault transmission line 3 becomes high-impedance due to a break or poor contact, the gate of FET12A is not connected to ground 23 in the fault transmission line 3, but is connected to ground 23 via input resistor 17, and the gate voltage becomes the cutoff voltage, thus switching it to the off state. As the second switching element 12, FET12A outputs a "high" level from its source to the operational circuit 6 when on, and when off, the source is not connected to the drain, thus not outputting a "high" level.

[0041] (Operational Circuit 6)

[0042] The operational circuit 6 detects the on / off state of the first switching element 11 of the voltage determination circuit 4 and the second switching element 12 of the impedance detection circuit 5, that is, it detects the "high" signal output from the voltage determination circuit 4 and the impedance detection circuit 5 to determine the fault of the battery module 2 and the abnormality of the fault transmission line 3. The operational circuit 6 determines the fault of the battery module 2 and the fault transmission line 3 under the following conditions.

[0043] 1. When the first switching element 11 of the voltage determination circuit 4 is in the off state and the second switching element 12 of the impedance detection circuit 5 is in the on state and outputs "high", all battery modules 2 are determined to be normal.

[0044] 2. When the first switching element 11 of the voltage determination circuit 4 is in the on state and outputs "high", and the second switching element 12 of the impedance detection circuit 5 is in the off state, it is determined that a certain battery module 2 is abnormal.

[0045] 3. When both the first switching element 11 of the voltage determination circuit 4 and the second switching element 12 of the impedance detection circuit 5 are in the off state, and neither outputs "high", it is determined that the faulty transmission line 3 is abnormal.

[0046] -Industry availability-

[0047] This invention can be effectively used in power supply devices with large outputs and multiple battery modules.

[0048] -Symbol Explanation-

[0049] 100... power supply device

[0050] 1...Module Fault Detection Circuit

[0051] 2... Battery Module

[0052] 3... Faulty transmission line

[0053] 4...Voltage determination circuit

[0054] 5... Impedance detection circuit

[0055] 6...operational circuit

[0056] 9... Power cord

[0057] 10...Pull-up power supply

[0058] 11...First switching element

[0059] 11A...FET

[0060] 12...Second switching element

[0061] 12A...FET

[0062] 13... Power Supply

[0063] 14...Input Resistance

[0064] 15... Diode

[0065] 16... Power Supply

[0066] 17...Input Resistance

[0067] 18...Zener diode

[0068] 19...ground wire

[0069] 21... Fault Determination Department

[0070] 22...Connecting terminals

[0071] 23...ground wire

[0072] 24...Short circuit switch

[0073] 24A...FET

[0074] 25... Pull-up resistor.

Claims

1. A power supply device, characterized in that, have: Multiple battery modules, including a fault determination unit, which determines whether a battery is faulty or normal and outputs fault and normal status using high-level and low-level signals; A fault transmission line is formed by connecting to the fault determination unit of each of the battery modules; and A module fault determination circuit is connected to the fault transmission line and determines whether the battery module is faulty or normal. The module fault determination circuit has the following features: A voltage determination circuit is used to determine the high or low level of the faulty transmission line. An impedance detection circuit is used to detect the impedance of the faulty transmission line relative to ground. as well as The calculation circuit determines whether the battery module is faulty or normal, and the abnormality of the fault transmission line, based on the outputs of the voltage determination circuit and the impedance detection circuit.

2. The power supply device according to claim 1, wherein, The power supply device includes: a pull-up power supply connected to the terminal of the fault transmission line via a series resistor to pull the voltage of the fault transmission line to a high level. The fault determination unit has a short-circuit switch, which connects the fault transmission line to the ground and sets it to a low level when the fault determination unit determines that a fault is present.

3. The power supply device according to claim 2, wherein, The fault determination unit is in the state of determining the fault of the battery module. Set the short-circuit switch to the ON state, and connect the fault transmission line to the ground and set it to a low level.

4. The power supply device according to claim 3, wherein, The voltage determination circuit includes a first switching element, which becomes an on state when detecting a low-level state of the faulty transmission line, and becomes an off state when detecting a high-level state of the faulty transmission line and a high impedance higher than a set impedance. The impedance detection circuit includes a second switching element, which is switched to an ON state when detecting a high-level state of the faulty transmission line, and switched to an OFF state when detecting a low-level state of the faulty transmission line and a high impedance higher than a set impedance. The computing circuit, When the first switching element is in the off state and the second switching element is in the on state, the battery module is determined to be normal. When the first switching element is in the ON state and the second switching element is in the OFF state, the battery module is determined to be abnormal. When the first and second switching elements are in the off state, the faulty transmission line is determined to be abnormal.

5. The power supply device according to claim 4, wherein, The first switching element is a p-channel FET. The FET uses its drain as the output, connects its source to the power supply, connects its gate to the power supply via an input resistor, and connects its gate to the fault transmission line via a diode. The diodes are connected in a positive orientation to allow current to flow from the gate side to the fault transmission line.

6. The power supply device according to claim 4 or 5, wherein, The second switching element is an n-channel FET. The FET uses its source as the output, connects its gate to ground via an input resistor, and connects its gate to the fault transmission line via a Zener diode. The Zener diode directs the current flowing from the gate to the fault transmission line in a positive direction. The voltage obtained by subtracting the Zener voltage from the high-level voltage of the fault transmission line is input to the gate, thereby setting the Zener voltage to the voltage that enables the FET to conduct.

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