WO2016031843A1

WO2016031843A1 - Charger

Info

Publication number: WO2016031843A1
Application number: PCT/JP2015/073956
Authority: WO
Inventors: 和寛新村; 守倉石; 慎司広瀬; 伊藤　智之; 量也山田
Original assignee: 株式会社豊田自動織機
Priority date: 2014-08-27
Filing date: 2015-08-26
Publication date: 2016-03-03
Also published as: JPWO2016031843A1

Abstract

A charger 10 is configured by being provided with a voltage identifying unit 42 that acquires a rated voltage of a storage battery, and a detecting means 6 that detects an abnormality of the charger 10, and the detecting means 6 changes an abnormality detection method corresponding to the rated voltage acquired by means of the voltage identifying unit 42.

Description

Charger

The present invention relates to technology for charging storage batteries of different rated voltages.

As a type of rechargeable storage battery, for example, there are a lithium ion battery, a lead battery, a nickel hydrogen battery and the like. A charger for charging different types of storage batteries needs to identify the type of storage battery and perform charging according to a charging voltage, a charging current and a charging control method suitable for the type of the storage battery.

As a charger for charging different types of storage batteries, the values of resistance and impedance provided in advance on the storage battery are read, the values are used as identification signals to determine the type of storage battery, and the determined charging characteristics of the type of storage battery A charger that performs charging by switching to a suitable charging circuit is known, for example, from Patent Document 1 below.

When a ground fault occurs in the feeder in the charger, an abnormal voltage or current is output that may damage equipment on the storage battery side or the charger side. Therefore, as a safety mechanism, the charger is provided with a ground fault detection circuit, and when a ground fault is detected, a measure such as issuing an alarm is taken.

FIG. 9 shows a configuration example of the ground fault detection circuit. As shown in FIG. 9, a ground fault detection circuit 3 for detecting a ground fault of the feed line 2 with respect to the feed line 2 of the charging unit 1 that supplies charging current to a storage battery (not shown) Be equipped.

The ground fault detection circuit 3 has one end of each of the

resistors

31 and 32 connected to the positive electrode potential line (+) and the negative electrode potential line (-) of the feed line 2 and the other end connected to the anode. A light emitting diode 34 is provided. The cathode of the light emitting diode 34 is connected to the ground potential conductor via a resistor 33.

The ground fault detection circuit 3 further includes a phototransistor 35 for receiving light emitted from the light emitting diode 34. The collector of the phototransistor 35 is connected to the power supply voltage terminal 36 through the resistor 37, and the emitter of the phototransistor 35 is Is connected to the ground potential conductor.

The output voltage of the collector of the phototransistor 35 is input to the input terminal of the control unit 4 through the resistor 38. The control unit 4 is configured using a CPU (Central Processing Unit) or the like. The light emitting diode 34 and the phototransistor 35 constitute a photocoupler.

When a ground fault does not occur in the feed line 2, a voltage obtained by dividing the positive electrode potential and the negative electrode potential of the feed line 2 by the

resistors

31 and 32 is applied to the anode of the light emitting diode 34. Then, a current flows in the light emitting diode 34 and the light emitting diode 34 emits light. When the light emitting diode 34 emits light, the phototransistor 35 is turned on, and a low level signal is output from its collector.

On the other hand, when a ground fault occurs in the feed line 2, the voltage obtained by dividing the positive electrode potential and the negative electrode potential of the feed line 2 by the

resistors

31 and 32 decreases, so the current flowing to the light emitting diode 34 decreases. Since the diode 34 does not emit light, the phototransistor 35 is turned off, and the collector of the phototransistor 35 outputs a high level signal.

As described above, either the high level signal or the low level signal from the collector of the phototransistor 35 is input to the input terminal of the control unit 4 depending on whether or not a ground fault has occurred. The determination unit 41 determines whether or not a ground fault has occurred based on the signal.

A battery charger including a ground fault detection circuit 3 for detecting a ground fault of the feeder 2 based on the voltage of the feeder 2 and charging a plurality of types of storage batteries with different rated voltages to charge a low-voltage storage battery When the charging voltage output from the feed line 2 is low, the threshold level for ground fault detection in the ground fault detection circuit 3 must be lowered.

If the threshold level for detecting the ground fault is lowered, when charging a storage battery of high voltage type, the charging voltage output from the feeding line 2 is high, so the voltage of the feeding line 2 is It does not fall below the threshold level for ground fault detection, and the occurrence of a ground fault may not be detected.

On the other hand, when the threshold level for detecting the ground fault is increased according to the storage battery of the high voltage type, when charging the storage battery of the low voltage type, the charging voltage output from the feed line 2 is low. Even if a fault does not occur, the charging voltage output from the feed line 2 becomes lower than the threshold level for ground fault detection, and the occurrence of a ground fault may be erroneously detected.

As described above, in the charger 10 that charges storage batteries of different types of rated voltage, the ground fault detection circuit 3 that detects a ground fault of the feed line 2 changes the charge voltage and the ground fault according to the type of storage battery in the feed line 2 The accuracy of the ground fault detection circuit 3 must be increased to distinguish it from the voltage change due to

In order to increase the accuracy of the ground fault detection circuit 3, it is necessary to design and adjust a complicated circuit, and it is necessary to use high precision components, resulting in an increase in cost. In addition, when the accuracy of the ground fault detection circuit 3 is low, there is a problem that the ground fault is erroneously detected.

In addition, when the output voltage of the battery charger becomes an over voltage due to the battery being overcharged or the battery charger becoming abnormal, the battery charger may be stopped so that the battery does not deteriorate due to the over voltage. See, for example, Patent Documents 2 to 4.

Moreover, as a storage battery mounted in a vehicle, storage batteries of a plurality of predetermined rated voltages, such as 24V storage batteries, 48V storage batteries, and 80V storage batteries, exist. Therefore, equip the charger with a plurality of protection functions corresponding to storage batteries with a plurality of rated voltages, or provide only a protection function corresponding to a storage battery with the highest rated voltage among the plurality of rated voltages in a charger. Is considered.

However, in the case where the battery charger is provided with a plurality of protection functions respectively corresponding to storage batteries of a plurality of rated voltages, the cost increases as the protection functions increase. In addition, when the battery charger is provided with only the protection function corresponding to the storage battery with the highest rated voltage, the protection function does not work for the storage battery with a low rated voltage, and the over-voltage protection accuracy is lowered.

Japanese Patent Laid-Open No. 2002-10508 JP 2012-143072 A JP, 2009-089453, A Japanese Patent Application Laid-Open No. 10-215523

In view of the above-mentioned subject, the present invention aims at performing abnormalities detection appropriately, suppressing the increase in cost, in the charger which can charge the storage battery of a different rated voltage.

A charger according to one aspect of the present invention is a charger for charging storage batteries different in rated voltage, and includes voltage information acquisition means for acquiring a rated voltage of a storage battery connected to the charger, and the charger The detection means changes the abnormality detection method according to the rated voltage acquired by the voltage information acquisition means.

ADVANTAGE OF THE INVENTION According to this invention, abnormality detection can be performed appropriately, suppressing the increase in cost in the charger which can charge the storage battery of a different rated voltage.

It is a figure which shows the structural example of the principal part of the charger of embodiment. It is a figure which shows the operation | movement example of a grounding detection at the time of charging the battery of multiple types of voltage. It is a figure which shows the other structural example of the principal part of the charger of embodiment. It is a figure which shows an example of an output overvoltage protection circuit. It is a flowchart which shows an example of operation | movement of a charger. It is a flowchart which shows an example of operation | movement of S33 shown in FIG. It is a figure which shows the modification of the charger shown in FIG. It is a figure which shows the modification of the charger shown in FIG. It is a figure which shows the structural example of a ground fault detection circuit.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The structural example of the principal part of the charger of this invention is shown in FIG. As shown in FIG. 1, a ground fault detection circuit 3 for detecting a ground fault of the feeder 2 with respect to the feeder 2 of the charging unit 1 for supplying charging current to a battery (not shown) (not shown) is a charger. 10 will be equipped.

The ground fault detection circuit 3 connects one end of each of the

resistors

31 and 32 to the positive electrode potential line (+) and the negative electrode potential line (-) of the feed line 2 as described in FIG. A light emitting diode 34 is connected to the other end of the light emitting diode. The cathode of the light emitting diode 34 is connected to the ground potential conductor via a resistor 33.

The ground fault detection circuit 3 further includes a phototransistor 35 for receiving light emitted from the light emitting diode 34. The collector of the phototransistor 35 is connected to the power supply voltage terminal 36 through the resistor 37, and the emitter of the phototransistor 35 is Is connected to the ground potential conductor. The output voltage of the collector of the phototransistor 35 is input to the input terminal of the control unit 4 through the resistor 38.

When a ground fault does not occur in the feed line 2, the light emitting diode 34 emits light, the phototransistor 35 is turned on, and the collector of the phototransistor 35 outputs a low level detection signal. On the other hand, when a ground fault occurs in the feed line 2, the light emitting diode 34 does not emit light, the phototransistor 35 is turned off, and the collector of the phototransistor 35 outputs a high level detection signal.

As a threshold level for ground fault detection in the ground fault detection circuit 3, that is, a threshold level at which the light emitting diode 34 is turned off, the voltage output from the feeder 2 at the time of charging the high voltage type battery is lowered due to the ground fault. The level at which this can be detected is set by the resistance value of the

resistors

31, 32, and 33, and the like.

A detection signal of high level or low level from the collector of the phototransistor 35 is input to the input terminal of the control unit 4 depending on whether or not a ground fault has occurred. Determine the occurrence of a fault. However, when the voltage of the battery (rated voltage of the storage battery) identified by the voltage identification unit 42 (voltage information acquisition unit) is less than or equal to a predetermined voltage, the ground fault determination unit 41 (ground fault determination unit) 3. Disable the ground fault detection based on the detection signal output from 3 and enable the ground fault detection based on the detection signal when the voltage of the battery is greater than a predetermined voltage. The ground fault judging unit 41 drives the ground fault detection circuit 3 by stopping the power supply to the ground fault detection circuit 3 when the voltage of the battery connected to the charger 10 is lower than a predetermined voltage. , And the ground fault detection circuit 3 may be continuously driven when the voltage of the battery connected to the charger 10 is larger than a predetermined voltage.

The voltage identification unit 42 is based on the information on the type of battery notified from the battery monitoring control unit on the battery side via the communication line 5 such as CAN (Controller Area Network) communication before the start of charging of the battery to be charged. The voltage of the battery (the rated voltage of the storage battery) can be identified. Alternatively, the voltage of the feeder 2 connected to the battery may be measured by the charging unit 1 before charging starts, and the voltage of the battery to be charged (rated voltage of the storage battery) may be identified based on the voltage.

For example, when charging a low voltage battery (such as a storage battery with a low rated voltage) of a low voltage such as 24 V or 48 V based on the voltage notified from the voltage identification unit 42, the ground fault determination unit 41 performs ground fault detection. In the case of disabling and charging a high voltage type battery (storage battery with high rated voltage) such as 80 V, for example, 60 V is defined as a predetermined voltage in order to enable ground fault detection. Then, for a battery with a predetermined voltage of 60 V or less (a storage battery with a rated voltage of 60 V or less), the ground fault detection is invalidated, and a battery with a predetermined voltage greater than 60 V (a rated voltage of greater than 60 V) Control) to enable ground fault detection.

As a result, when charging the low voltage battery, for example, a battery of multiple voltages of 24 V to 80 V can be charged by one type of charger without erroneous detection of a ground fault. In the charging of a low voltage battery (for example, a battery of 24V and 48V), even if a ground fault occurs in the feeder 2, no major damage is caused to the battery side or the charger side. There is no problem even if it is invalidated.

In addition, when the charger 10 and the battery are connected by a charging cable, the battery voltage (rated voltage of the storage battery) is determined based on the information on the type of the battery notified via the communication line 5 such as CAN communication. By identifying and validating the ground fault detection based on the voltage of the battery, it is possible to determine the ground fault detection in a short time.

FIG. 2 shows an operation flow example of ground fault detection when charging a battery of a plurality of types of voltages. First, when charging of the battery is started, the voltage identification unit 42 identifies the voltage of the battery (rated voltage of the storage battery) by the information notified from the battery side through communication such as CAN communication (step S21).

The ground fault determination unit 41 compares the voltage of the battery identified by the voltage identification unit 42 with a predetermined voltage (step S22), and if the battery voltage is greater than the predetermined voltage (YES in step S22), ground fault detection The ground fault detection by the detection signal obtained from the circuit 3 is validated (step S23), and the ground fault detection by the detection signal obtained from the ground fault detection circuit 3 when the battery voltage is less than the predetermined voltage (NO in step S22) Are invalidated (step S24).

Thereafter, the charger 10 determines various conditions of charge, and when the ground fault is not detected and various conditions are satisfied, charging of the battery is started. On the other hand, when the condition of charge is not satisfied, such as when a ground fault is detected, measures for ensuring safety such as issuing an alarm are executed.

FIG. 3: is a figure which shows the other structural example of the principal part of the charger of embodiment.

The charger 1a shown in FIG. 3 is a charger for charging a vehicle such as an electric forklift or a plug-in hybrid vehicle, and includes a charging cable 2a. Charging connector 3a provided at the end of charging cable 2a is connected to charging connector 4a provided on the vehicle side, and battery pack 5a is provided from battery charger 1a via power line in charging cable 2a and charging

connectors

3a and 4a. When power is supplied to 51 (storage battery) (for example, a lithium ion battery), the battery 51 is charged.

Further, the charger 1 a includes a power supply unit 11 and a control unit 12.

The power supply unit 11 includes a PFC (Power Factor Correction) circuit (power factor correction circuit) 111, an isolated DC / DC converter circuit 112, a non-insulated DC / DC converter circuit 113, and a power unit control unit 115 (threshold setting). Section) and an output overvoltage protection circuit (protection section) 116.

The PFC circuit 111 includes a rectifier circuit, a coil, a switching element, a diode, a capacitor, a control circuit, and the like. The switching element is repeatedly turned on and off by the control circuit to convert AC power supplied from the external power supply 6a into DC. Convert.

The isolated DC / DC converter circuit 112 includes a switching element, a capacitor, a coil, a transformer, a rectifier circuit, a smoothing circuit, a control circuit, and the like, and the control circuit repeatedly outputs the PFC circuit 111 by turning on and off the switching element. The transmitted power is transmitted from the primary coil of the transformer to the secondary coil, and the power transmitted to the secondary coil is rectified and smoothed by the rectifier circuit and the smoothing circuit and output.

The non-insulated DC / DC converter circuit 113 includes a switching element, a coil, a capacitor, a diode, a control circuit, and the like, and the control circuit repeatedly outputs the isolated DC / DC converter circuit 112 by turning on and off the switching element. Step-down or boost-up the voltage.

The power supply unit control unit 115 drives the power supplied from the isolated DC / DC converter 112 by stepping down the power for the control unit, and drives the PFC circuit 111, the isolated DC / DC converter circuit 112, and the non-insulated DC / DC converter. Each operation of the DC converter circuit 113 is controlled.

The control unit 12 includes an AC / DC circuit 121, a control unit control unit 122 having a communication unit 1221 (voltage information acquisition means), a charger state display unit 123, and a storage unit 124.

The AC / DC circuit 121 converts AC power supplied from the external power supply 6a into DC power.

The control unit control unit 122 is driven by the power supplied from the AC / DC circuit 121, and controls the entire charger 1a. For example, the communication unit 1221 of the control unit control unit 122 sets the current command value transmitted from the battery pack control unit 52 provided in the battery pack 5a to the

charge connectors

3a and 4a and the communication line in the charge cable 2a (for example, CAN ( Controller Area Network) received via the communication line for communication, and the received current command value is transmitted to the power supply unit control unit 115 via the communication line (for example, communication line for CAN communication) in the charger 1a. Do. The power supply unit control unit 115 controls the PFC circuit 111 and the isolated DC / DC converter such that the power or current corresponding to the current command value transmitted from the communication unit 1221 of the control unit control unit 122 is output from the charger 1a. The operation of each of the circuit 112 and the non-insulated DC / DC converter circuit 113 is controlled.

The charger state display unit 123 includes, for example, a plurality of lamps indicating various states (standby, charging, abnormality, etc.) of the charger 1a, and a lamp corresponding to a control signal sent from the control unit control unit 122 Light.

The power supply unit control unit 115, the control unit control unit 122, and the battery pack control unit 52 are, for example, a micro control unit (MCU), a central processing unit (CPU), a multicore CPU, a programmable device (field programmable gate (FPGA) (Array), PLD (Programmable Logic Device), and the like. Further, the storage unit 124 is configured by, for example, a non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read Only Memory).

For example, when the control unit controller 122 detects that the charge connector 3a is connected to the charge connector 4a, the communication unit 1221 makes a transmission request for voltage information via the communication line in the charge cable 2a and the

charge connectors

3a and 4a. And sends it to the battery pack control unit 52.

When the battery pack control unit 52 receives the transmission request for voltage information, the control unit control unit controls the voltage information indicating the voltage of the battery 51 (rated voltage of the storage battery) (for example, 24V system, 48V system, or 80V system) Send to 122

When the voltage information is received by the communication unit 1221, the control unit control unit 122 determines, based on the received voltage information, how many V-system batteries 51 the power supply destination battery 51 is, and communicates the determination result It transmits to the power supply unit control part 115 by the part 1221 via the communication line in the charger 1a.

When the power supply unit control unit 115 receives the determination result transmitted from the control unit control unit 122, the power supply unit control unit 115 sets the threshold value Vth based on the received determination result.

The output overvoltage protection circuit 116 stops the non-insulated DC / DC converter circuit 113 when the output voltage of the non-insulated DC / DC converter circuit 113 becomes equal to or higher than the threshold value Vth. That is, when the output voltage of the power supply unit including the PFC circuit 111, the isolated DC / DC converter circuit 112, and the non-insulated DC / DC converter circuit 113 becomes equal to or higher than the threshold Vth, the output overvoltage protection circuit 116 Stop.

FIG. 4 is a diagram showing an example of the output overvoltage protection circuit 116. As shown in FIG.

The output overvoltage protection circuit 116 shown in FIG. 4 includes

resistors

21 and 22, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) 23, a resistor 24, and a comparator 25.

The

resistors

21 and 22 are connected in series to each other, and provided between the output of the non-insulated DC / DC converter circuit 113 and the ground. The drain terminal of the MOSFET 23 is connected to the negative terminal of the comparator 25 and one end of the resistor 24, and the source terminal of the MOSFET 23 is connected to the reference GND. The other end of the resistor 24 is connected to a voltage source. The positive input terminal of the comparator 25 is connected to the connection point of the

resistors

21 and 22. The signal output from the comparator 25 is input to the non-insulated DC / DC converter circuit 113. The power supply unit control unit 115 inputs a pulse signal of the Duty ratio according to the determination result transmitted from the control unit control unit 122 to the gate terminal of the MOSFET 23, and turns the MOSFET 23 on and off repeatedly. When the MOSFET 23 is repeatedly turned on and off, a voltage corresponding to the duty ratio of the pulse signal output from the power supply unit controller 115 is input to the negative input terminal of the comparator 25. The output voltage of the non-insulated DC / DC converter circuit 113 is divided by the

resistors

21 and 22 and input to the positive input terminal of the comparator 25. The comparator 25 outputs a high level signal when the voltage input to the positive input terminal is larger than the voltage input to the negative input terminal, and the voltage input to the negative input terminal is positive. When it is larger than the voltage input to the input terminal on the side, it outputs a low level signal. When the battery 51 is charged, the non-insulated DC / DC converter circuit 113 supplies power to the battery 51 by repeatedly turning on and off switching elements provided therein when the signal output from the comparator 25 is at a low level. To continue. In addition, when the battery 51 is charged, the non-insulated DC / DC converter circuit 113 turns off the switching element provided in the battery 51 when the signal output from the comparator 25 changes from the low level to the high level. Turn off the power supply.

For example, it is assumed that 35 V is set as the threshold value Vth corresponding to "24V battery 51". When the output voltage of the non-insulated DC / DC converter circuit 113 is 35 V or more, a voltage larger than 3.5 V is input to the positive input terminal of the comparator 25, and the non-insulated DC / DC converter circuit 113 It is assumed that the resistance values of the

resistors

21 and 22 are selected such that a voltage smaller than 3.5 V is input to the positive input terminal of the comparator 25 when the output voltage is smaller than 35 V. Further, 10 V is applied to the drain terminal of the MOSFET 23. Also, when the judgment result transmitted from the control unit control unit 122 to the power supply unit control unit 115 is "24V battery 51", a pulse having an on duty ratio of 65% from the power supply unit control unit 115 to the gate terminal of the MOSFET 23 A signal is output, and a voltage of 3.5 V (= 10 V × (1−0.65)) is input to the negative input terminal of the comparator 25.

In such a case, when the output voltage of the non-insulated DC / DC converter circuit 113 is smaller than 35 V, a voltage smaller than 3.5 V is input to the positive input terminal of the comparator 25. At this time, since the voltage input to the negative input terminal of the comparator 25 is larger than the voltage input to the positive input terminal, the comparator 25 outputs a low level signal. Therefore, the non-insulated DC / DC converter circuit 113 continues the power supply to the battery 51 by repeatedly turning on and off the switching element provided therein.

When the output voltage of the non-insulated DC / DC converter circuit 113 is 35 V or more, a voltage larger than 3.5 V is input to the positive input terminal of the comparator 25. At this time, the voltage input to the positive input terminal of the comparator 25 is larger than the voltage input to the negative input terminal, so the comparator 25 outputs a high level signal. Therefore, the non-insulated DC / DC converter circuit 113 stops the power supply to the battery 51 by turning off the switching element provided therein.

Further, for example, it is assumed that 60 V is set as the threshold value Vth corresponding to “48-V battery 51”. When the output voltage of the non-insulated DC / DC converter circuit 113 is 60 V or more, a voltage larger than 6.0 V is input to the positive input terminal of the comparator 25, and the non-insulated DC / DC converter circuit 113 It is assumed that the resistance values of the

resistors

21 and 22 are selected such that a voltage smaller than 6.0 V is input to the positive input terminal of the comparator 25 when the output voltage is smaller than 60 V. Further, 10 V is applied to the drain terminal of the MOSFET 23. In addition, when the judgment result transmitted from the control unit control unit 122 to the power supply unit control unit 115 is “48V system battery 51”, a pulse with an on duty ratio of 40% from the power supply unit control unit 115 to the gate terminal of the MOSFET 23 A signal is output, and a voltage of 6.0 V (= 10 V × (1−0.4) is input to the negative input terminal of the comparator 25.

In such a case, when the output voltage of the non-insulated DC / DC converter circuit 113 is smaller than 60 V, a voltage smaller than 6.0 V is input to the positive input terminal of the comparator 25. At this time, since the voltage input to the negative input terminal of the comparator 25 is larger than the voltage input to the positive input terminal, the comparator 25 outputs a low level signal. Therefore, the non-insulated DC / DC converter circuit 113 continues the power supply to the battery 51 by repeatedly turning on and off the switching element provided therein.

When the output voltage of the non-insulated DC / DC converter circuit 113 is 60 V or more, a voltage larger than 6.0 V is input to the positive input terminal of the comparator 25. At this time, the voltage input to the positive input terminal of the comparator 25 is larger than the voltage input to the negative input terminal, so the comparator 25 outputs a high level signal. Therefore, the non-insulated DC / DC converter circuit 113 stops the power supply to the battery 51 by turning off the switching element provided therein.

Further, for example, it is assumed that 90 V is set as the threshold value Vth corresponding to the “80 V battery 51”. When the output voltage of the non-insulated DC / DC converter circuit 113 is 90 V or more, a voltage larger than 9.0 V is input to the positive input terminal of the comparator 25, and the non-insulated DC / DC converter circuit 113 It is assumed that the resistance values of the

resistors

21 and 22 are selected such that a voltage smaller than 9.0 V is input to the positive input terminal of the comparator 25 when the output voltage is smaller than 90 V. Further, 10 V is applied to the drain terminal of the MOSFET 23. Also, when the judgment result transmitted from the control unit control unit 122 to the power supply unit control unit 115 is “80V system battery 51”, a pulse having an on duty ratio of 10% from the power supply unit control unit 115 to the gate terminal of the MOSFET 23 A signal is output, and a voltage of 9.0 V (= 10 V × (1-0.1) is input to the negative input terminal of the comparator 25.

In such a case, when the output voltage of the non-insulated DC / DC converter circuit 113 is smaller than 90 V, a voltage smaller than 9.0 V is input to the positive input terminal of the comparator 25. At this time, since the voltage input to the negative input terminal of the comparator 25 is larger than the voltage input to the positive input terminal, the comparator 25 outputs a low level signal. Therefore, the non-insulated DC / DC converter circuit 113 continues the power supply to the battery 51 by repeatedly turning on and off the switching element provided therein.

In addition, when the output voltage of the non-insulated DC / DC converter circuit 113 is 90 V or more, a voltage larger than 9.0 V is input to the positive input terminal of the comparator 25. At this time, the voltage input to the positive input terminal of the comparator 25 is larger than the voltage input to the negative input terminal, so the comparator 25 outputs a high level signal. Therefore, the non-insulated DC / DC converter circuit 113 stops the power supply to the battery 51 by turning off the switching element provided therein.

FIG. 5 is a flowchart showing an example of the operation of the charger 1a.

First, the control unit controller 122 stands by until the charge connector 3a is connected to the charge connector 4a (S31: No), and detects that the charge connector 3a is connected to the charge connector 4a (S31: Yes), Voltage information is acquired (S32).

Next, the control unit controller 122 and the power supply unit controller 115 set the threshold value Vth based on the voltage information (S33).

Next, when the output overvoltage protection circuit 116 determines that the output voltage of the non-insulated DC / DC converter circuit 113 is smaller than the threshold value Vth (S34: No), it returns to the operation of S34 and performs overvoltage protection processing for the battery 51. continue.

When the output overvoltage protection circuit 116 determines that the output voltage of the non-insulated DC / DC converter circuit 113 is equal to or higher than the threshold Vth (S34: Yes), the non-insulated DC / DC converter circuit 113 is stopped ( S35), the overvoltage protection process for the battery 51 is finished.

FIG. 6 is a flowchart showing an example of the operation of S33 shown in FIG.

First, based on the voltage information, the control unit controller 122 determines that the battery 51 to which the power is supplied is "24V battery 51", and the determination result is transmitted from the control unit controller 122 to the power supply unit controller 115. If it is (S41: Yes), the power supply unit control unit 115 sets the threshold value Vth corresponding to the "24V battery 51" which is the judgment result (S42).

Further, the control unit control unit 122 determines that the battery 51 of the power supply destination is the “48V system battery 51” based on the voltage information, and the determination result is transmitted from the control unit control unit 122 to the power supply unit control unit 115 Then (S41: No, S43: Yes), the power supply unit control unit 115 sets a threshold value Vth corresponding to "48V battery 51" which is the judgment result (S44).

Further, the control unit control unit 122 determines that the battery 51 of the power supply destination is the “80V battery 51” based on the voltage information, and the determination result is transmitted from the control unit control unit 122 to the power supply unit control unit 115 If it is (S41: No, S43: No, S45: Yes), the power supply unit control unit 115 sets the threshold value Vth corresponding to "80V battery 51" which is the judgment result (S46).

In addition, it is determined that the control unit control unit 122 can not identify the battery 51 of the power supply destination based on the voltage information and the battery 51 of the power supply destination can not be identified. When transmitted to 115 (S41: No, S43: No, S45: No), the power supply unit controller 115 determines that an abnormality has occurred based on the determination result, and stops the non-insulated DC / DC converter circuit 113. Then, the overvoltage protection process for the battery 51 is ended (S47).

The charger 1a of the embodiment sets the threshold value Vth based on the voltage information transmitted from the battery pack 5a, and when the output voltage of the non-insulated DC / DC converter circuit 113 becomes equal to or higher than the threshold value Vth, the non-insulated DC Since the configuration is such that the / DC converter circuit 113 is stopped, overvoltage protection can be performed on the batteries 51 of a plurality of voltages determined in advance by one output overvoltage protection circuit 116. As a result, while suppressing the increase in the cost of the charger 1a, it is possible to prevent the overvoltage protection accuracy from being lowered for the battery 51 of a plurality of voltages determined in advance.

In addition, you may employ | adopt the charger 1a of embodiment as a charger mounted in a vehicle.

As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment described above, It can take various structure or embodiment in the range which does not deviate from the summary of this invention. it can.

FIG. 7 is a view showing a modification of the charger 10 shown in FIG. In FIG. 7, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted.

The charger 10 shown in FIG. 7 includes a detection unit 6, and the detection unit 6 includes, for example, a ground fault detection circuit 3 and a ground fault determination unit 41.

As described above, the ground fault detection circuit 3 detects a ground fault of the feed line 2. That is, the ground fault detection circuit 3 detects an abnormality of the charger 10.

In addition, the ground fault determination unit 41 detects the detection output of the ground fault detection circuit 3 when the voltage of the battery (rated voltage of the storage battery) acquired by the voltage identification unit 42 (voltage information acquisition means) is less than a predetermined voltage. When the voltage of the battery (rated voltage of the storage battery) acquired by the voltage identification unit 42 is larger than a predetermined voltage, the detection output of the ground fault detection circuit 3 is validated. That is, the ground fault determination unit 41 changes the abnormality detection method according to the rated voltage of the storage battery acquired by the voltage identification unit 42 (voltage information acquisition unit).

As described above, the detection unit 6 detects an abnormality of the charger 10 and changes the abnormality detection method according to the rated voltage of the storage battery acquired by the voltage identification unit 42 (voltage information acquisition unit).

Thereby, in the charger 10 capable of charging storage batteries of different rated voltages, the method can be changed to an appropriate abnormality detection method according to the rated voltage of the storage battery, so that the abnormality detection accuracy can be enhanced.

FIG. 8 is a view showing a modification of the charger 1a shown in FIG. In FIG. 8, the same components as those shown in FIG. 3 will be assigned the same reference numerals and descriptions thereof will be omitted.

The charger 1a shown in FIG. 8 includes a detection unit 117. The detection unit 117 includes, for example, a power supply unit control unit 115 and an output overvoltage protection circuit 116.

As described above, when the output overvoltage of the power supply unit including the PFC circuit 111, the isolated DC / DC converter circuit 112, the non-insulated DC / DC converter circuit 113, etc. Stop the power supply unit. That is, the output overvoltage protection circuit 116 detects an abnormality of the charger 1a.

Further, the power supply unit control unit 115 sets the threshold value Vth based on the voltage of the battery 51 (rated voltage of the storage battery) acquired by the communication unit 1221 (voltage information acquisition unit). That is, the power supply unit control unit 115 changes the abnormality detection method according to the voltage (rated voltage of the storage battery) of the battery 51 acquired by the communication unit 1221 (voltage information acquisition unit).

As described above, the detection unit 117 detects an abnormality of the charger 1 a and changes the abnormality detection method according to the voltage of the battery 51 (rated voltage of the storage battery) acquired by the communication unit 1221 (voltage information acquisition unit). .

As a result, in the battery charger 1a capable of charging storage batteries of different rated voltages, the method can be changed to an appropriate abnormality detection method according to the rated voltage of the storage battery, so that the abnormality detection accuracy can be enhanced.
[Supplementary Note 1]
A charger that charges multiple types of batteries with different voltages,
A ground fault detection circuit that detects a ground fault of the feed line;
Voltage identification means for identifying the voltage of the battery to be charged;
When the voltage of the battery to be charged is lower than a predetermined voltage, the detection output of the ground fault detection circuit is invalidated, and when the voltage of the battery to be charged is larger than a predetermined voltage, the detection output of the ground fault detection circuit is effective. Ground fault judging means to
A charger characterized by comprising.
[Supplementary Note 2]
The battery charger according to claim 1, wherein the voltage identification unit identifies a voltage of the battery based on information notified from the battery side by communication before starting charging of the battery.
[Supplementary Note 3]
It is a ground fault detection judging method of a feeder line when charging a plurality of types of batteries with different voltages,
A voltage identification step identifying the voltage of the battery to be charged;
When the voltage of the battery to be charged is less than a predetermined voltage, the detection output of the ground fault detection circuit for detecting a ground fault of the feed line is invalidated, and the voltage of the battery to be charged is larger than the predetermined voltage A ground fault judgment step of validating the detection output of the detection circuit;
A ground fault detection judging method characterized by including.
[Supplementary Note 4]
The ground fault detection / determination method according to claim 3, wherein the voltage identification step identifies the voltage of the battery based on information notified from the battery side by communication before starting charging of the battery. .
[Supplementary Note 5]
A power supply unit for supplying power to the battery provided in the battery pack;
A communication unit that receives voltage information indicating the voltage of the battery from the battery pack;
A threshold setting unit configured to set a threshold based on the voltage information;
A protection unit for stopping the power supply unit when the output voltage of the power supply unit is equal to or higher than the threshold value;
A charger characterized by comprising.
[Supplementary Note 6]
A charging control method for controlling the operation of the power supply unit in a charger including a power supply unit for supplying power to a battery provided in a battery pack,
The charger is
Receiving voltage information indicating the voltage of the battery from the battery pack;
Setting a threshold based on the voltage information;
The power supply unit is stopped when the output voltage of the power supply unit is equal to or more than the threshold value.

DESCRIPTION OF SYMBOLS 1 charge part 2 feeder 3 ground

fault detection circuit

31, 32, 33, 33, 38, resistance 34 light emitting diode 35 phototransistor 36 power supply voltage terminal 4 control part 41 ground fault decision part 42 voltage discrimination part 5 communication line 6 detection means 1a Charger

2a Charging Cable

3a, 4a Charging Connector 5a Battery Pack 6a External Power Supply 117 Detection Means 11 Power Supply Unit 12 Control Unit 51 Battery 52 Battery Pack Control Unit 111 PFC Circuit 112 Isolated DC / DC Converter Circuit 113 Non-Isolated DC / DC Converter circuit 115 power supply unit control unit 116 output overvoltage protection circuit 121 AC / DC circuit 122 control unit control unit 123 charger state display unit 124 storage unit 1221 communication unit

Claims

A charger for charging storage batteries of different rated voltages,
Voltage information acquisition means for acquiring a rated voltage of a storage battery connected to the charger;
Detection means for detecting an abnormality of the charger;
Consists of
The said detection means changes the abnormality detection method according to the rated voltage acquired by the said voltage information acquisition means.
The charger according to claim 1, wherein
The detection means is
A ground fault detection circuit that detects a ground fault of the feed line;
When the rated voltage acquired by the voltage information acquiring means is equal to or lower than a predetermined voltage, the detection output of the ground fault detecting circuit is nullified, and the rated voltage acquired by the voltage information acquiring means is larger than the predetermined voltage Ground fault judging means for validating the detection output of the ground fault detection circuit;
A charger characterized by comprising.
The charger according to claim 1, wherein
The voltage information acquisition means is a storage battery connected to the charger based on information notified from the storage battery side connected to the charger by communication before starting charging of the storage battery connected to the charger. A charger characterized by obtaining a rated voltage.
The charger according to claim 1, wherein
A power supply unit for supplying power to a storage battery connected to the charger;
The detection means is
A threshold setting unit configured to set a threshold based on the rated voltage acquired by the voltage information acquisition unit;
A protection unit for stopping the power supply unit when the output voltage of the power supply unit is equal to or higher than the threshold value;
A charger characterized by comprising.