Power supply

Abstract

The objective of the present invention is to reliably determine failure of a battery module.　This power source device is provided with: a plurality of battery modules (2), each including a failure determining unit (21) which determines failure and normal operation and outputs failure and normal operation as "High" and "Low" signals; a failure transmitting line (3) which is connected to the failure determining units (21) of each battery module (2); and a module failure determining circuit (1) which is connected to the failure transmitting line (3), and which determines failure and normal operation of the battery modules (2). The module failure determining circuit (1) is provided with: a voltage determining circuit (4) for determining "High" and "Low" of the failure transmitting line (3); an impedance detecting circuit (5) for detecting an impedance with respect to a ground line (23); and a calculating circuit (6) for determining failure and normal operation of the battery modules (2), and an abnormality of the failure transmitting line (3), from the outputs of the voltage determining circuit (4) and the impedance detecting circuit (5).

Description

[Technical field]

[0001] The present invention relates to a power supply device having a plurality of battery modules, and more particularly to a power supply device in which the failure / normal state of each battery module is transmitted to a module failure determination circuit via a failure transmission line. [Background technology]

[0002] Power supply devices equipped with multiple battery modules can increase the number of battery modules to increase the charge / discharge capacity and thus the output, and are therefore used as power supply devices for electric vehicles, power storage devices, etc. These power supply devices detect failures in each battery module to ensure stable operation (see Patent Document 1).

[0003] The above power supply device is provided with a self-diagnostic fault determination unit in each battery module to determine whether it is faulty or normal, and each battery module is connected to a fault transmission line and to a module fault determination circuit that determines whether all battery modules are faulty or normal, thereby monitoring the status of all battery modules. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-087129 A Summary of the Invention [Problem to be solved by the invention]

[0005] The power supply device can determine the failure of each battery module by the module failure determination circuit. This power supply device connects the failure determination unit provided in each battery module to a failure transmission line, and can detect that any of the battery modules has failed by the module failure determination circuit. In this power supply device, the failure determination unit of each battery module connected to the failure transmission line outputs a "High" signal in a normal state and a "Low" signal in a failed state, and the module failure determination circuit determines that all battery modules are normal when the failure transmission line is in a "High" state, and determines that any of the battery modules is failed when the failure transmission line is in a "Low" state. A power supply device that determines whether a battery module is failed or normal based on the "High" and "Low" of the failure transmission line cannot accurately determine whether a battery module is failed or normal by detecting "High" and "Low" when the failure transmission line is not normal, for example, when the failure transmission line has poor contact or is disconnected. Therefore, a power supply device that determines whether a battery module is failed based only on "High" and "Low" cannot always accurately determine whether a battery module is failed or normal.

[0006] The present invention has been developed with the further object of overcoming the above-mentioned drawbacks, and one object of the present invention is to provide a power supply device that can reliably determine a failure in a battery module. [Means for solving the problem]

[0007] A power supply device according to one embodiment of the present invention includes a plurality of battery modules each having a failure determination unit that determines whether the battery module is in a failure state or a normal state and outputs the failure or normal state as a "High" or "Low" signal, a failure transmission line connected to the failure determination unit of each battery module, and a module failure determination circuit connected to the failure transmission line and determining whether the battery module is in a failure state or a normal state. The module failure determination circuit includes a voltage determination circuit that determines whether the failure transmission line is "High" or "Low", an impedance detection circuit that detects the impedance with respect to the ground line, and an arithmetic circuit that determines whether the battery module is in a failure state or a normal state and an abnormality in the failure transmission line from the outputs of the voltage determination circuit and the impedance detection circuit. Effect of the Invention

[0008] The power supply device described above has the advantage that it can more reliably detect failures in the battery modules. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram of a power supply device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will be described in detail below with reference to the drawings. In the following description, terms indicating specific directions or positions (e.g., "upper", "lower", and other terms including these terms) are used as necessary, but the use of these terms is for the purpose of facilitating understanding of the invention with reference to the drawings, and the meanings of these terms do not limit the technical scope of the present invention. In addition, parts with the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or members. Furthermore, the embodiments shown below are specific examples of the technical ideas of the present invention, and do not limit the present invention to the following. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended to be illustrative and not to limit the scope of the present invention. Furthermore, the contents described in one embodiment or example can be applied to other embodiments or examples. Furthermore, the sizes and positional relationships of the components shown in the drawings may be exaggerated to clarify the explanation.

[0011] A power supply device according to a first embodiment of the present invention includes a plurality of battery modules each having a failure determination unit that determines whether the battery module is in a failure state or a normal state and outputs the failure or normal state as a "High" or "Low" signal, a failure transmission line connected to the failure determination unit of each battery module, and a module failure determination circuit connected to the failure transmission line and determining whether the battery module is in a failure state or a normal state. The module failure determination circuit includes a voltage determination circuit that determines whether the failure transmission line is "High" or "Low", an impedance detection circuit that detects the impedance relative to the ground line, and an arithmetic circuit that determines whether the battery module is in a failure state or a normal state and an abnormality in the failure transmission line from the outputs of the voltage determination circuit and the impedance detection circuit.

[0012] The above power supply device has the advantage of being able to detect failures in battery modules more reliably. In particular, it can reliably detect whether a battery module is faulty or normal, and whether a faulty transmission line is abnormal. This is because the above power supply device uses a calculation circuit to determine whether a battery module is faulty or normal, and whether a faulty transmission line is abnormal, based on the output of a voltage determination circuit that determines whether the faulty transmission line is "High" or "Low," and an impedance detection circuit that detects the impedance to the ground line.

[0013] A power supply device according to a second embodiment of the present invention includes a pull-up power supply connected to an end of a fault transmission line via a pull-up resistor and configured to pull up a voltage of the fault transmission line to "High." Detect and It is equipped with a short-circuit switch that connects the faulty transmission line to the ground line, making it “Low.”

[0014] In the power supply device of the third embodiment of the present invention, when the failure determination section determines that a battery module has a failure, the short-circuit switch is turned on and the failure transmission line is connected to the ground line to be "Low."

[0015] A power supply device according to a fourth embodiment of the present invention includes a voltage determination circuit having a first switching element which is turned on when it detects a "low" state of the faulty transmission line and turned off when it detects 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 which is turned on when it detects a "high" state of the faulty transmission line and turned off when it detects a "low" state of the faulty transmission line and a high impedance higher than a set impedance. In this power supply device, an arithmetic circuit determines that the battery module is normal when the first switching element is in the off state and the second switching element is in the on state, determines that the battery module is abnormal when the first switching element is in the on state and the second switching element is in the off state, and determines that the faulty transmission line is abnormal when the first switching element and the second switching element are in the off state.

[0016] In the above power supply device, the arithmetic circuit determines whether the battery module is faulty or normal, and whether there is an abnormality in the faulty transmission line, based on the on / off state of the first switching element of the voltage judgment circuit and the second switching element of the impedance detection circuit, so that the power supply device has the advantage of being able to easily and reliably detect faults in the battery module and abnormalities in the faulty transmission line.

[0017] In a power supply device of a fifth embodiment of the present invention, the first switching element is a p-channel FET, the drain of the FET is connected as an output, the source is connected to a power supply, and the gate is connected to the power supply via an input resistor and is also connected to a fault transmission line via a diode, with the diode connected in a direction such that the current flowing from the gate side to the fault transmission line is the forward direction.

[0018] In a power supply device of a sixth embodiment of the present invention, the second switching element is an n-channel FET, the source of the FET is the output, and the gate is connected to a ground line via an input resistor and to a fault transmission line via a Zener diode. The Zener diode is oriented in such a way that the current flowing from the gate to the fault transmission line is in the forward direction, and the Zener voltage is set to a voltage that turns the FET on when a voltage obtained by subtracting the Zener voltage from the "High" level voltage of the fault transmission line is input to the gate.

[0019] (Embodiment 1) The power supply device 100 of Figure 1 comprises a plurality of 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 an abnormality in the fault transmission line 3 based on the impedance of the fault transmission line 3.

[0020] (Battery module 2) The battery module 2 incorporates a plurality of rechargeable battery cells (not shown), and further includes a circuit board (not shown) on which a protection circuit for detecting the voltage and remaining capacity of the battery cells is mounted. The battery module 2 includes a fault determination unit 21 that determines whether the battery module 2 is in a normal state or has a fault. The fault determination unit 21 detects, for example, a fault in a battery cell or a circuit board, and sets a 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 a ground line 23. The short-circuit switch 24 can be a semiconductor switching element such as a FET or a transistor, but the fault determination unit 21 in FIG. 1 uses the short-circuit switch 24 as a FET 24A, and when a fault is determined, an ON voltage is input to the gate to switch the FET 24A to the ON state, and when a fault is determined, the gate voltage of the FET 24A is set to an OFF voltage to switch the FET 24A to the OFF state.

[0021] (Faulty transmission line 3) The fault transmission line 3 is connected at its end to the positive side of the pull-up power supply 10 via a pull-up resistor 25, and when the short-circuit switch 24 is in the off state, the connection terminal 22 of the fault transmission line 3 becomes "High." The power supply device 100 in FIG. 1 has a pull-up power supply 10 provided in the module fault determination circuit 1, which is connected to the end of the fault transmission line 3 via the power supply line 9 and the pull-up resistor 25. The power supply device 100 does not specify the voltage of the pull-up power supply 10, but it is set to, for example, 12V.

[0022] The FET 24A of the short-circuit switch 24 of the failure determination unit 21 of the battery module 2 is in the OFF state in a normal state, so that the connection terminal 22 is at the "High" level when the battery module 2 is in a normal state. When the battery module 2 is in a fault state, the FET 24A of the short-circuit switch 24 is switched to the ON state, so that when the failure determination unit 21 determines that there is a fault, the connection terminal 22 is connected to the ground line 23 by the FET 24A of the short-circuit switch 24 and is at the "Low" level.

[0023] Each battery module 2 connects the connection terminal 22 of the failure determination unit 21 to the failure transmission line 3. Therefore, when the failure determination unit 21 of any battery module 2 detects a failure and switches the short-circuit switch 24 to the ON state, the failure transmission line 3 is connected to the ground line 23 via the ON-state short-circuit switch 24 and becomes at the "Low" level. When all battery modules 2 are operating normally, the short-circuit switches 24 of all battery modules 2 are held in the OFF state, and the failure transmission line 3 is held in the "High" state.

[0024] (Module fault detection circuit 1) The module failure judgment circuit 1 includes a voltage judgment circuit 4 which judges 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 with respect to the ground line 23, and a calculation circuit 6 which judges 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 judgment circuit 4 and the impedance detection circuit 5.

[0025] (Voltage judgment circuit 4) The voltage determination circuit 4 detects the voltage of the fault transmission line 3 and determines whether each battery module 2 is faulty or normal. The voltage determination circuit 4 includes a first switching element 11 that detects the "Low" state of the fault transmission line 3 to turn on and detects the "High" state to turn off. The first switching element 11 is a p-channel FET 11A. This FET 11A has a drain connected to the arithmetic circuit 6 as the output side, a source connected to a power source 13, and a gate connected to the power source 13 via an input resistor 14 and also connected to the fault transmission line 3 via a diode 15. The diode 15 is connected in a direction such that the current flowing from the gate side to the fault transmission line 3 is the forward direction.

[0026] In the voltage determination circuit 4 described above, when the voltage of the fault transmission line 3 is at the "High" level, no current flows through the diode 15, and the gate of the p-channel FET 11A is connected to the source and is in the OFF state. When the fault transmission line 3 becomes the "Low" level, electricity is passed through the fault transmission line 3 from the power source 13 via the input resistor 14 and the forward diode 15, and a negative ON voltage with respect to the power source 13 is input to the gate of the FET 11A, and the FET 11A is in the ON state. In addition, since the fault transmission line 3 is in an abnormal state and has a high impedance, electricity cannot be passed from the power source 13 to the forward direction of the diode 15 through the high impedance fault transmission line 3, and the gate of the FET 11A becomes "High" and the FET 11A is in the OFF state. In this voltage determination circuit 4, the FET 11A of the first switching element 11 is in the ON state only when the battery module 2 is in a faulty state, i.e., when any one of the battery modules 2 is in a faulty state, and a "High" signal is output from the drain of the FET to the calculation circuit 6. When all the battery modules 2 are in a normal state, or when the fault transmission line 3 is in an abnormal state, the FET 11A of the first switching element 11 is in an off state and does not output "High."

[0027] (Impedance detection circuit 5) The impedance detection circuit 5 includes a second switching element 12. The second switching element 12 is switched on when it detects the "High" level of the fault transmission line 3, and switched off when it detects the "Low" level of the fault transmission line 3 and high impedance. The second switching element 12 that operates as described above is an n-channel FET 12A, and the drain of this FET 12A is connected to the power supply 16 as the input side, and the source is connected to the arithmetic circuit 6 as the output side, and the gate is connected to the ground line 19 via an input resistor 17 and to the fault transmission line 3 via a Zener diode 18. The Zener diode 18 turns the FET 12A off when the fault transmission line 3 is at the "Low" level, with the current flowing from the gate to the fault transmission line 3 being the forward direction. Furthermore, the Zener voltage of the Zener diode 18 is set to a voltage that is obtained by subtracting the Zener voltage from the "High" level voltage of the fault transmission line 3 and inputting it to the gate of the FET 12A to turn the FET 12A on. Furthermore, the Zener voltage of the Zener diode 18 is set higher than the voltage input from the power supply 13 of the voltage determination circuit 4 via the diode 15 in the forward direction when the fault transmission line 3 is in a high impedance state.

[0028] In the impedance detection circuit 5 described above, when the fault transmission line 3 is in a "High" level state, an on voltage is input to the gate of the FET 12A via the Zener diode 18, and the FET 12A is in an on state. When the fault transmission line 3 is in a "Low" level state, the gate is connected to the ground line 23 via the Zener diode 18 and the input resistor 17, and the gate voltage of the FET 12A becomes a cutoff voltage and is in an off state. Furthermore, when the fault transmission line 3 is in a high impedance state due to a break or poor contact of the fault transmission line 3, the gate of the FET 12A is not connected to the ground line 23 by the fault transmission line 3, but is connected to the ground line 23 via the input resistor 17, and the gate voltage becomes a cutoff voltage and is switched to an off state. The FET 12A, which is the second switching element 12, outputs a "High" level from the source to the calculation circuit 6 in an on state, and in an off state, the source is not connected to the drain, and does not output a "High" level.

[0029] (Arithmetic circuit 6) The arithmetic circuit 6 detects the on / off of the first switching element 11 of the voltage evaluation circuit 4 and the second switching element 12 of the impedance detection circuit 5, i.e., the "High" signals output from the voltage evaluation circuit 4 and the impedance detection circuit 5, to determine whether there is a fault in the battery module 2 and an abnormality in the fault transmission line 3. The arithmetic circuit 6 determines whether there is a fault in the battery module 2 and the fault transmission line 3 in the following states.

[0030] 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. 2. When the first switching element 11 of the voltage determination circuit 4 is on and outputs “High”, and the second switching element 12 of the impedance detection circuit 5 is off, it is determined that one of the battery modules 2 is abnormal. 3. When both the first switching element 11 of the voltage judgment circuit 4 and the second switching element 12 of the impedance detection circuit 5 are in the off state and neither of them outputs “High”, it is determined that an abnormality has occurred in the fault transmission line 3. [Industrial Applicability]

[0031] The present invention can be effectively used in applications where a large-output power supply device is equipped with a plurality of battery modules. [Explanation of symbols]

[0032] 100...Power supply device 1...Module failure detection circuit 2. Battery module 3…Faulty transmission line 4. Voltage judgment circuit 5. Impedance detection circuit 6...Arithmetic circuit 9…Power line 10...Pull-up power supply 11...First switching element 11A…FET 12...Second switching element 12A…FET 13...Power supply 14…Input resistance 15…Diode 16…Power supply 17…Input resistance 18...Zener diode 19...Grand Line 21...Failure determination section 22...Connection terminal 23...Grand Line 24...Short circuit switch 24A…FET 25...Pull-up resistor

Claims

1. A plurality of battery modules each having a failure determination unit that determines whether the battery module is in a normal state or a fault and outputs a "High" or "Low" signal indicating the failure or normal state; a fault transmission line connected to the fault determination unit of each of the battery modules; connected to the faulty transmission line; a module failure determination circuit for determining whether the battery module is normal or not; The module failure determination circuit includes: a voltage determination circuit for determining whether the faulty transmission line is "High" or "Low"; an impedance detection circuit for detecting an impedance with respect to a ground line; From the outputs of the voltage determination circuit and the impedance detection circuit, A power supply device comprising: an arithmetic circuit for determining whether the battery module is in a normal state or not and whether the fault transmission line is in an abnormal state.

2. 2. The power supply device according to claim 1, connected to the end of the fault transmission line via a series resistor, A pull-up power supply is provided for pulling up the voltage of the fault transmission line to "High"; The failure determination unit, Detecting the fault, A power supply device comprising a short-circuit switch that connects the fault transmission line to a ground line to set it to "Low."

3. 3. The power supply device according to claim 2, The failure determination unit, In a state in which a failure of the battery module is determined, The short switch is turned on, A power supply device characterized in that the fault transmission line is connected to a ground line to set it to "Low."

4. 4. The power supply device according to claim 3, The voltage determination circuit is Detecting the "Low" state of the faulty transmission line and turning it on; a first switching element that detects a "high" state of the faulty transmission line and a high impedance higher than a set impedance and is turned off; The impedance detection circuit includes: Detecting the "high" state of the faulty transmission line to turn on; a second switching element that detects a "low" state of the faulty transmission line and a high impedance higher than a set impedance and is switched to an off state; The arithmetic circuit comprises: The first switching element is in an off state, When the second switching element is in an on state, determining that the battery module is normal; The first switching element is in an on state, When the second switching element is in an off state, determining that the battery module is abnormal; When the first switching element and the second switching element are in an off state, A power supply device characterized in that it is determined that the fault is an abnormality in the failure transmission line.

5. 5. The power supply device according to claim 4, the first switching element is a p-channel FET, The FET is The drain is the output, Connect the source to the power supply. The gate is connected to the power supply through an input resistor, connected to the faulty transmission line via a diode; The diode is A power supply device characterized in that the power supply is connected in a direction in which a current flowing from the gate side to the fault transmission line is a forward direction.

6. 6. The power supply device according to claim 4 or 5, the second switching element is an n-channel FET, The FET is The source is the output, The gate is connected to the ground line via an input resistor, connected to the fault transmission line via a Zener diode; The Zener diode is A direction in which a current flows from the gate to the fault transmission line is a forward direction, The Zener voltage is The voltage obtained by subtracting the Zener voltage from the “High” level voltage of the fault transmission line is input to the gate, 1. A power supply device, characterized in that a voltage is set to turn on an FET.

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