JP2008037211A - Power supply device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply device for a vehicle capable of correctly detecting a non-connection state by directly detecting the connection state of a high-voltage line. <P>SOLUTION: The power supply device for the vehicle comprises a battery 1, an output connector 11 for attachably and detachably connecting the battery 1 to a high-voltage line 4 connected to a load of the vehicle via a first contactor 2A and a second contactor 2B, and an interlock circuit 3 which detects the non-connection state of the high-voltage line 4 and switches the contactor 2 from an on-state to an off-state. The interlock circuit 3 comprises an oscillation circuit 5 for outputting an AC detection signal to a first output line 4A between the first contactor 2A and the output connector 11, and a discrimination circuit 6 which is connected to an output line 4B between the second contactor 2B and the output connector 11 to detect a signal transmitted to the second output line 4B and detect the non-connection state of the high-voltage line 4. In the power supply device, the discrimination circuit 6 detects the non-connection state of the high-voltage line 4, switches the contactor 2 to the off-state, and shuts off the output of the battery 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power supply device for a vehicle, and more particularly to a power supply device for a vehicle that shuts off the output of a battery with a contactor when a high voltage line connecting the power supply device to a load on the vehicle side is disconnected.

  FIG. 1 shows a circuit diagram of a conventional vehicle power supply apparatus. This power supply device connects a battery 31 of the power supply device to the vehicle side via an output connector 41. In the power supply device, when the output connector 41 is removed, the output terminal 46 of the power supply is exposed to the outside. Since the output terminal 46 is connected to the battery 31 and becomes a high-voltage direct current, in order to prevent an electric shock, the contactor 32 for cutting off the output of the power supply is provided in the state where the output connector 41 is removed. An interlock circuit 33 is provided to turn off the contactor 32 with the output connector 41 removed. The interlock circuit 33 detects the non-connection state of the interlock wire 34 provided in the output connector 41 and switches the contactor 32 off. This is because the interlock wire 34 is disconnected when the output connector 41 is disconnected.

Further, the power supply device shown in the figure has an interlock switch 44 in series with the battery 31. For example, when the power supply device is repaired, the interlock switch 44 cuts off the output voltage and improves safety. The interlock switch 44 is manually operated when, for example, repairing the power supply device, or is detected from the opening of the case and switched from on to off. The power supply device with the interlock switch 44 can be safely operated by shutting off the output circuit during maintenance. In this power supply device, a detection switch 45 for detecting on / off of the interlock switch 44 is connected in series with the interlock wire 34, and is connected to the output side of the battery 31 when the interlock switch 44 is switched off. The safety can be improved by switching the contactor 32 off. Thus, a power supply device in which the interlock switch 44 is provided in series with the battery 31 has been developed. (See Patent Document 1)
Japanese Patent Laid-Open No. 2004-1652

  The power supply device including the interlock circuit 33 shown in FIG. 1 can improve safety by switching the contactor 32 to OFF with the interlock wire 34 disconnected. The interlock circuit 33 shown in the figure includes a current output circuit 36 that outputs a detection current to the interlock wire 34 and a current detection circuit 37 that detects a detection current output from the current output circuit 36. The non-connection state of the interlock wire 34 is determined from the current. However, in order to detect the attachment / detachment of the output connector, this power supply device needs to connect an interlock wire to the output connector and short-circuit the interlock wire on the vehicle side, and the structure becomes complicated. In addition, since the disconnection state of the high voltage line is detected via the interlock wire, if the interlock wire is disconnected or a contact failure occurs in the output connector to which the interlock wire is connected, the disconnection state of the high voltage line There is a detection that cannot be detected accurately.

  The present invention has been developed for the purpose of solving this drawback. An important object of the present invention is to directly detect the connection state of the high voltage line, accurately detect the disconnection state, and securely shut off the contactor when the high voltage line is disconnected. An object of the present invention is to provide a power supply device for a vehicle that can improve performance.

The vehicle power supply device of the present invention has the following configuration in order to achieve the above-described object.
The power supply device for a vehicle has a battery 1, a positive voltage side and a negative electrode side of the battery 1 connected via a first contactor 2A and a second contactor 2B, and a high voltage connected to a vehicle load. An output connector 11 that removably connects the line 4 and an interlock circuit 3 that detects an unconnected state of the high-voltage line 4 and switches the contactor 2 from on to off to cut off the output of the battery 1 are provided. The interlock circuit 3 includes an oscillation circuit 5 that outputs an AC detection signal to a first output line 4A that is a line between the first contactor 2A and the output connector 11, and a second contactor 2B and output connector 11. A determination circuit 6 connected to the second output line 4B, which is a line between the first and second lines, detecting a signal transmitted to the second output line 4B and detecting a non-connected state of the high voltage line 4. Prepare. In the power supply device, the determination circuit 6 detects the non-connection state of the high voltage line 4 and switches the contactor 2 off to cut off the output of the battery 1.

  In the vehicle power supply device of the present invention, a plurality of batteries 1 are connected in series at an intermediate connection point 12, and a signal transmitted from the determination circuit 6 to the second output line 4 </ b> B and the intermediate connection point 12 of the battery 1 are connected. Thus, the non-connection state of the high voltage line 4 can be detected.

  The power supply device for a vehicle according to the present invention includes a main detection circuit 15 in which a plurality of batteries 1 are connected in series at an intermediate connection point 12 so that the determination circuit 6 detects a signal of the second output line 4B; A sub-detection circuit 16 for detecting a signal at the intermediate connection point 12; and an arithmetic circuit 9 for determining a non-connection state of the high-voltage line 4 from signals detected by the main detection circuit 15 and the sub-detection circuit 16. it can.

  In the power supply device for a vehicle according to the present invention, a plurality of batteries 1 are connected in series at an intermediate connection point 12, and the determination circuit 6 has a difference between the signal of the second output line 4 </ b> B and the signal of the intermediate connection point 12 of the battery. A differential amplifier 17 for detecting a voltage is provided, and a non-connected state of the high voltage line 4 can be detected from a signal detected by the differential amplifier 17.

  In the vehicle power supply device of the present invention, the oscillation circuit 5 connects the output side to the first output line 4A and the ground 20, and the discrimination circuit 6 connects the input side to the second output line 4B and the ground 20. Can be connected.

  In the power supply device for a vehicle of the present invention, the oscillation circuit 5 outputs to the line between the positive electrode side of the battery 1 and the first contactor 2A, and the discrimination circuit 6 includes the negative electrode side of the battery 1 and the second contactor 2B. It is possible to determine a welding failure of the contactor 1 by detecting a signal of a line between the contactor 1 and the contact line 1.

  The vehicle power supply device of the present invention connects a plurality of batteries 1 in series at an intermediate connection point 12, and a main detection circuit 15 in which a determination circuit 6 detects a signal of the second output line 4 B; A sub-detection circuit 16 that detects a signal at the intermediate connection point 12, and a calculation circuit 9 that determines a welding failure of the contactor 2 from signals detected by the main detection circuit 15 and the sub-detection circuit 16 can be provided.

  In the power supply device for a vehicle according to the present invention, a plurality of batteries 1 are connected in series at the intermediate connection point 12, and the discriminating circuit 6 receives the signal of the second output line 4 </ b> B and the signal of the intermediate connection point 12 of the battery 1. A differential amplifier 17 for detecting the differential voltage is provided, and a welding failure of the contactor 2 can be determined from a signal detected by the differential amplifier 17.

  In the power supply device for a vehicle of the present invention, the oscillation circuit 5 connects the output side to the chassis ground 22 of the vehicle via the leakage detection resistor 21, and the determination circuit 6 detects the voltage of the leakage detection resistor 21 to increase the voltage. The leakage fault of the voltage line 4 can be determined.

  In the power supply device for a vehicle according to the present invention, the determination circuit 6 can detect the non-connected state of the high voltage line 4 by detecting the operating frequency (switching frequency) of the inverter on the vehicle side.

  In order to detect the connection state of the high voltage line, the vehicle power supply device of the present invention connects an interlock wire to the output connector connected to the high voltage line as in the prior art, and further connects the interlock wire to the output connector. There is no need to connect to the vehicle side in parallel with the high voltage line. This is because the connection and disconnection of the high voltage line are directly detected. That is, the power supply device of the present invention outputs a detection signal from the oscillation circuit to one high voltage line, transmits this detection signal from one high voltage line to the other high voltage line, and detects the transmitted signal. This is because the connection and disconnection state of the high voltage line is detected. In addition to omitting the interlock wire, the power supply device with this structure can eliminate false detection due to a failure of the interlock wire provided for detecting the disconnection state of the high voltage line. The conventional device that detects the disconnection state of the high voltage line with the interlock wire connected to the output connector together with the high voltage line cannot eliminate the detection error due to the disconnection of the interlock wire or the contact failure of the output connector. Since the power supply device of the present invention directly detects whether or not the high voltage line is connected, there is no false detection due to a failure of the interlock wire, and the high voltage line can be reliably detected without being detected. Is in a state of being disconnected, there is a feature that the contactor can be reliably cut off to improve safety.

  According to a second aspect of the present invention, there is provided a power supply device in which a plurality of batteries are connected in series at an intermediate connection point, and a signal transmitted to the second output line is determined by a determination circuit and an intermediate connection point of the battery. Since the signal is detected to detect the disconnection state of the high voltage line, it is possible to more accurately determine whether the high voltage line is connected or disconnected. It detects a battery-side transmission signal transmitted from the battery side to the second output line with a signal detected at the intermediate connection point of the battery, and includes the battery included in the signal detected at the second output line This is because the side transmission signal can be canceled or attenuated. Since the signal from which the battery-side transmission signal is canceled is a signal transmitted from the high voltage line side, the signal changes significantly depending on whether the high voltage line is connected or not. For this reason, the apparatus which can detect the disconnection state of a high voltage line with the signal which cancels a battery side transmission signal can detect the disconnection state of a high voltage line correctly.

  Furthermore, a power supply device according to a third aspect of the present invention includes a main detection circuit that detects a signal of the second output line, a sub detection circuit that detects a signal at an intermediate connection point of the battery, a main detection circuit, and a sub detection circuit. Since the discrimination circuit is composed of the arithmetic circuit that discriminates the disconnection state of the high-voltage line from the signal detected in step 1, the arithmetic circuit detects the high voltage from the difference signal between the signals detected by the main detection circuit and the sub detection circuit. It can detect line connection and disconnection accurately. That is, the difference signal between the main detection circuit and the sub detection circuit becomes a signal in which the battery side transmission signal is canceled, and the signal level transmitted from the high voltage line side can be increased to detect the disconnection state of the high voltage line. Because.

  Furthermore, the power supply device according to claim 4 of the present invention is provided with a differential amplifier for detecting a differential voltage between the signal of the second output line and the signal of the intermediate connection point of the battery, and the differential amplifier detects the differential voltage. Since the non-connected state of the high voltage line is detected from the generated signal, the circuit configuration can be simplified and the non-connected state of the high voltage line can be accurately detected. It uses a differential amplifier to attenuate the battery-side transmission signal in real time in the state of an analog signal from the signal detected on the second output line and increase the signal level from the high voltage line side to increase the voltage This is because the unconnected state of the line can be determined.

  According to a fifth aspect of the present invention, the output side of the oscillation circuit is connected to the first output line and the ground, and the discrimination circuit detects the signal of the second output line with respect to the ground. Since the disconnection state of the high voltage line is detected, the output of the oscillation circuit can be reduced to accurately determine the disconnection state of the high voltage line. This is because, even if the pair of high voltage lines are connected with an extremely low impedance load on the vehicle side, the pair of high voltage lines are changed by a detection signal with respect to the ground. The discrimination circuit also detects the voltage fluctuation of the second output line that fluctuates with respect to the ground, so that the high voltage line is accurately disconnected without being affected by the low impedance load of the pair of high voltage lines. Can be detected.

  Furthermore, the power supply device according to claim 6 of the present invention is characterized in that it is possible to determine a contactor welding failure. This is because the power supply device outputs the signal from the oscillation circuit to the line between the positive electrode side of the battery and the first contactor, and detects the signal of the line between the negative electrode side of the battery and the second contactor by the discrimination circuit. This is because the welding failure of the contactor is determined. In this power supply device, the detection signal detected by the discrimination circuit is different between the state in which the contactor is welded and held in the on state and the state in which the contactor is normally switched off. It is possible to accurately determine the welding failure.

  Furthermore, the power supply device according to claim 9 of the present invention has a feature that it is possible to determine a leakage fault of the high voltage line. This is because this power supply device connects the output side of the oscillation circuit to the chassis ground of the vehicle via a leakage detection resistor, and detects the leakage failure of the high voltage line by detecting the voltage of the leakage detection resistor by the discrimination circuit. Because. In the power supply device, when the high voltage line leaks, the high voltage line is connected to the chassis ground via the leakage resistance, and the leakage current generates a voltage at both ends of the leakage detection resistor. Therefore, the voltage induced at both ends of the leakage detection resistor can be detected by the discrimination circuit, and the leakage of the high voltage line can be detected.

  Embodiments of the present invention will be described below with reference to the drawings. However, the following embodiment exemplifies a power supply device for a vehicle for embodying the technical idea of the present invention, and the present invention does not specify the power supply device as follows.

  Further, in this specification, in order to facilitate understanding of the scope of claims, numbers corresponding to the members shown in the examples are indicated in the “claims” and “means for solving problems” sections. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  The vehicle power supply device shown in FIGS. 2 to 4 includes a battery 1, a contactor 2 that cuts off the output of the battery 1, and an interlock circuit 3 that controls the contactor 2. The interlock circuit 3 detects the non-connection state of the high voltage line 4 and switches the contactor 2 off to cut off the output of the battery 1.

  In the illustrated power supply apparatus, a plurality of batteries 1 are connected in series. Furthermore, the power supply device shown in the figure has two battery units 10 formed by connecting a plurality of batteries 1 in series and connected in series at an intermediate connection point 12. The positive and negative battery units 10 are connected in series via an interlock switch 14 at an intermediate connection point 12. In this power supply device, a large number of batteries 1 are connected in series to increase the output voltage, for example, several hundred volts. The battery 1 can be any rechargeable battery such as a nickel-hydrogen battery or a lithium ion secondary battery.

  The contactor 2 includes a first contactor 2A connected to the positive electrode side of the battery 1 and a second contactor 2B connected to the negative electrode side. The positive side and negative side contactors 2 are simultaneously switched from on to off to block the positive side and negative side outputs of the battery 1. In the illustrated power supply apparatus, the first contactor 2A is connected between the positive electrode side of the battery 1 and the output connector 11, and the second contactor 2B is connected between the negative electrode side of the battery 1 and the output connector 11. Yes. However, although not shown, the power supply device of the present invention can connect the first contactor to the negative electrode side of the battery and connect the second contactor to the positive electrode side of the battery.

  The interlock circuit 3 of FIG. 2 includes an oscillation circuit 5 that outputs an AC detection signal to the high voltage line 4 and a determination circuit 6 that detects a signal transmitted through the high voltage line 4. The oscillation circuit 5 is connected to a first output line 4A between the first contactor 2A and the output connector 11, and outputs an AC detection signal thereto. The discrimination circuit 6 is connected to the second output line 4B between the second contactor 2B and the output connector 11, and detects a signal transmitted to the second output line 4B via the high voltage line 4. Thus, the non-connection state of the high voltage line 4 is detected.

  The oscillation circuit 5 connects the output side to the ground 20 and the first output line 4A, and outputs a 1 kHz sine wave as a detection signal to the ground 20 on the first output line 4A. However, the oscillation circuit 5 can also output a sine wave or a rectangular wave having a frequency of 100 Hz to 1 MHz as a detection signal. The oscillation circuit 5 detects not only a single frequency sine or a single-period rectangular wave but also a sine wave obtained by synthesizing a plurality of frequency components or a synthetic wave of rectangular waves having different periods and amplitudes as a detection signal. It can also be output. Furthermore, the oscillation circuit 5 can output a detection signal obtained by modulating a carrier wave with a signal wave as a detection signal. The carrier wave is a sine wave having a frequency of 100 Hz to 10 MHz, for example. The oscillation circuit 5 connects a coupling capacitor 13 on the output side, cuts a direct current component with the coupling capacitor 13, and outputs a detection signal to the first output line 4A.

  The determination circuit 6 has an input side connected to the second output line 4B and the ground 20, and detects a signal transmitted to the second output line 4B to determine whether the high voltage line 4 is disconnected. To do. The determination circuit 6 includes a filter 7 connected to the input side, an A / D converter 8 connected to the output side of the filter 7, and an arithmetic circuit 9 connected to the output side of the A / D converter 8. With. The filter 7 is a high-pass filter or a band-pass filter that removes a noise component included in a signal detected from the second output line 4B. The A / D converter 8 converts the analog signal from which noise has been removed by the filter 7 into a digital signal. This is because the arithmetic circuit 9 calculates the digital signal to determine the non-connection state of the high voltage line 4. The arithmetic circuit 9 determines the non-connection state of the high voltage line 4 from the signal input from the A / D converter 8.

  The arithmetic circuit 9 determines the connection state of the high voltage line 4 with a signal transmitted from the high voltage line 4. The detection signal output from the oscillation circuit 5 is transmitted to the second output line 4B via the battery side, and is transmitted to the second output line 4B via the high voltage line side. The detection signal is transmitted to the second output line 4B by two circuits on the battery side and the high voltage line side. Signals transmitted from the battery side and the high voltage line side to the second output line 4B have different waveforms. This is because the battery side and the high voltage line have different electrical characteristics such as line impedance. Therefore, the signal transmitted from the battery side to the second output line 4B is constant and does not change. On the other hand, the signal transmitted from the high voltage line side to the second output line 4B is remarkably different depending on whether the high voltage line 4 is connected or not. This is because when the high voltage line 4 is not connected, that is, in a disconnected state, no signal is transmitted from the first output line 4A to the second output line 4B via the high voltage line 4. Therefore, the waveform transmitted to the second output line 4B varies depending on whether the high voltage line 4 is connected or not. The arithmetic circuit 9 stores a waveform transmitted to the second output line 4B in a state where the high voltage line 4 is connected in a memory (not shown) as a connection waveform, and the high voltage line 4 is not connected. In a non-connected state, a signal transmitted to the second output line 4B is stored as a non-connected waveform. The memory stores the connection waveform and the non-connection waveform, for example, the frequency analysis (FFT) of the transmission waveform at the amplitude ratio of each frequency.

  The arithmetic circuit 9 is a signal detected from the second output line 4B, and the signal converted into a digital signal is subjected to FFT, and compared with the connection waveform and the non-connection waveform to be stored, the non-connection of the high voltage line 4 is detected. Determine the connection status. A signal detected by the determination circuit 6 from the second output line 4B in a state where the high voltage line 4 is connected is a connection signal. Further, the signal detected by the determination circuit 6 from the second output line 4B when the high voltage line 4 is disconnected is a disconnected signal. Therefore, the arithmetic circuit 9 performs the FFT on the signal detected from the second output line 4B and compares it with the connection signal and the non-connection signal, and determines the non-connection state of the high voltage line 4 depending on which signal is close. Can be determined.

  3 and 4 detects the signal transmitted to the second output line 4B and also detects the signal at the intermediate connection point 12 of the battery 1 to determine whether the high voltage line 4 is disconnected. Determine. The reason for detecting the signal at the intermediate connection point 12 of the battery 1 is to detect the signal transmitted from the battery side to the second output line 4B. Signals are transmitted from both the battery side and the high voltage line side to the second output line 4B. In other words, the signal detected from the second output line 4B includes both signals transmitted from the battery side and the high voltage line side. 3 and 4 detects the signal at the intermediate connection point 12 of the battery 1 to detect the signal transmitted from the battery side to the second output line 4B, and the signal at the intermediate connection point 12 is detected. By removing the signal transmitted from the second output line 4B and attenuating or canceling the signal transmitted from the battery side, the signal on the high voltage line side can be accurately detected. For this reason, there is a feature that it is possible to prevent erroneous determination due to a signal transmitted from the battery side and accurately determine whether the high voltage line 4 is connected or not.

  3 includes a main detection circuit 15 that detects a signal of the second output line 4B, a sub detection circuit 16 that detects a signal of the intermediate connection point 12 of the battery 1, a main detection circuit 15, and a sub detection. An arithmetic circuit 9 for determining whether the high voltage line 4 is connected or not is provided from a signal detected by the circuit 16. Although not shown, each of the main detection circuit 15 and the sub detection circuit 16 includes a filter that removes noise from an input signal and an A / D converter that converts the output of the filter into a digital signal. The digital signals output from the main detection circuit 15 and the sub detection circuit 16 are separately input to the arithmetic circuit 9, and the arithmetic circuit 9 calculates the separately input signals to determine the connection state of the high voltage line 4. . The determination circuit 6 calculates digital signals input from the main detection circuit 15 and the sub detection circuit 16 to determine the non-connection state of the high voltage line 4.

  The arithmetic circuit 9 detects the unconnected state of the high voltage line 4 from the difference signal between the output signals of the main detection circuit 15 and the sub detection circuit 16. The main detection circuit 15 detects a signal transmitted from the battery side and the high voltage line side to the second output line 4B, and the sub detection circuit 16 mainly detects a signal transmitted to the battery side. Therefore, when the arithmetic circuit 9 detects the difference signal of the output signal of the sub detection circuit 16 from the output signal of the main detection circuit 15, the signal is transmitted from the high voltage line side to the second output line 4B. This difference signal is significantly different between when the high voltage line 4 is connected and when it is not connected. When the high voltage line 4 is not connected, that is, in a disconnected state, no signal is transmitted from the first output line 4A to the second output line 4B via the high voltage line 4, and the high voltage line 4 is connected. This is because the detection signal is transmitted from the high voltage line 4 in the state. Therefore, the difference signal between the main detection circuit 15 and the sub detection circuit 16 changes depending on whether the high voltage line 4 is connected or not.

  The arithmetic circuit 9 stores a difference signal between the main detection circuit 15 and the sub detection circuit 16 in a memory (not shown) as a connection waveform in a state in which the high voltage line 4 is connected. The difference signal between the main detection circuit 15 and the sub detection circuit 16 is stored as a non-connection waveform in a non-connection state where the connection is not established. The memory stores the connection waveform and the non-connection waveform, for example, the frequency analysis (FFT) of the transmission waveform at the amplitude ratio of each frequency.

  The arithmetic circuit 9 performs an FFT on the difference signal between the main detection circuit 15 and the sub detection circuit 16 and compares the stored connection waveform and the non-connection waveform to determine the non-connection state of the high voltage line 4. In a state where the high voltage line 4 is connected, a difference signal between the main detection circuit 15 and the sub detection circuit 16 becomes a connection signal stored in the memory. Further, in a non-connection state in which the high voltage line 4 is not connected, a difference signal between the main detection circuit 15 and the sub detection circuit 16 becomes a non-connection signal. Therefore, the arithmetic circuit 9 performs the FFT on the difference signal between the main detection circuit 15 and the sub detection circuit 16 and compares it with the connection signal and the non-connection signal. The state can be determined.

  4 includes a differential amplifier 17 that compares the signal of the second output line 4B and the signal of the intermediate connection point 12 of the battery 1 in the state of an analog signal. The differential amplifier 17 is a signal transmitted via the battery side from the difference signal between the signal of the second output line 4B and the signal of the intermediate connection point 12, in other words, the signal transmitted to the second output line 4B. Remove or attenuate. Therefore, the output level of the differential amplifier 17 increases the signal level transmitted from the high voltage line 4. The signal transmitted from the high voltage line 4 changes greatly depending on whether the high voltage line 4 is connected or not. Therefore, the signal of the differential amplifier 17 is calculated to connect or disconnect the high voltage line 4. It can be detected accurately. In order to detect connection and disconnection of the high voltage line 4, the analog signal output from the differential amplifier 17 is input to the A / D converter 8 after removing noise by the filter 7. The A / D converter 8 converts the input difference signal into a digital difference signal and inputs the difference signal to the arithmetic circuit 9. The arithmetic circuit 9 determines the non-connection state of the high voltage line 4 from the difference signal of the input digital signal.

  Further, the discrimination circuit 6 of FIG. 4 has preamplifiers 18 and 19 connected to the input side of the differential amplifier 17. The signal of the second output line 4B is amplified by the preamplifier 18 and input to the positive input terminal of the differential amplifier 17. The signal at the intermediate connection point 12 of the battery 1 is also amplified by the preamplifier 19 and input to the negative input terminal of the differential amplifier 17. The amplification factors of the preamplifiers 18 and 19 connected to the plus side and the minus side of the differential amplifier 17 are adjusted so that the signal transmitted through the battery side included in the output of the differential amplifier 17 is minimized. . Since the determination circuit 6 can effectively attenuate or remove the signal transmitted from the battery side and detect the signal transmitted from the high voltage line side, it can connect and disconnect the high voltage line 4 more accurately. Connection can be determined.

  The arithmetic circuit 9 detects the unconnected state of the high voltage line 4 from the difference signal output from the differential amplifier 17. The difference signal output from the differential amplifier 17 changes significantly depending on whether the high voltage line 4 is connected or not. When the high voltage line 4 is not connected, that is, in a disconnected state, no signal is transmitted from the first output line 4A to the second output line 4B via the high voltage line 4, and the high voltage line 4 is connected. This is because the detection signal is transmitted through the high voltage line 4 in the state. Therefore, the difference signal of the differential amplifier 17 changes depending on whether the high voltage line 4 is connected or not.

  The arithmetic circuit 9 stores the difference signal output from the differential amplifier 17 as a connection waveform in a memory (not shown) in a state where the high voltage line 4 is connected, and the high voltage line 4 is not connected. In a disconnected state, the difference signal output from the differential amplifier 17 is stored as a disconnected waveform. The memory stores the connection waveform and the non-connection waveform, for example, the frequency analysis (FFT) of the transmission waveform at the amplitude ratio of each frequency.

  The arithmetic circuit 9 performs an FFT on the difference signal output from the differential amplifier 17 and compares the stored connection waveform and the non-connection waveform to determine the non-connection state of the high voltage line 4. In a state where the high voltage line 4 is connected, the difference signal output from the differential amplifier 17 becomes a connection signal stored in the memory. In a non-connected state where the high voltage line 4 is not connected, the difference signal output from the differential amplifier 17 has a non-connected waveform. Therefore, the arithmetic circuit 9 performs an FFT on the difference signal output from the differential amplifier 17 and compares it with the connection signal and the non-connection signal. Can be determined.

  When the determination circuit 6 determines that the high voltage line 4 is connected, the positive side and the negative side of the battery 1 are connected to the vehicle side. In this state, the contactor 2 is turned on to supply electric power from the battery 1 to the vehicle.

Other embodiments are shown in FIGS. 5 to 8 below, and the same components as those in the above-described embodiments are denoted by the same reference numerals and description thereof is omitted.
5 to 7 show circuit diagrams of a power supply device that can detect welding of the contactor 2 using an AC detection signal output from the oscillation circuit 5. In the power supply apparatus shown in these drawings, the output of the oscillation circuit 5 is connected to a line between the positive electrode side of the battery 1 and the first contactor 2A.

  In the power supply device of FIG. 5, the determination circuit 6 detects a signal on a line between the negative electrode side of the battery 1 and the second contactor 2 </ b> B to determine a welding failure of the contactor 2. The power supply device of this figure can determine the welding of the contactor 2 from the detection signal detected by the determination circuit 6 in a state in which the contactor 2 is controlled to be turned off. This is because the detection signal detected by the determination circuit 6 differs between the state in which the contactor 2 is welded and held in the on state and the state in which the contactor 2 is normally switched off. The transmission path of the detection signal output from the oscillation circuit 5 differs depending on whether the contactor 2 is on or off. In a state where the contactor 2 is welded and cannot be switched off, the detection signal output from the oscillation circuit 5 is transmitted from the contactor 2 and the load side to the determination circuit 6 in addition to the battery side. On the other hand, in the state where the contactor 2 is switched off, the detection signal is not transmitted to the determination circuit 6 from the contactor 2 side, but is transmitted only from the battery 1 side. Therefore, the detection signal detected by the determination circuit 6 differs between the ON state and the OFF state, and the welding of the contactor 2 can be detected by the difference in the detection signal.

  6 outputs a detection signal on the output side of the oscillation circuit 5 to the line between the positive electrode side of the battery 1 and the first contactor 2A, and the discrimination circuit 6 is connected to the second output line 4B. The main detection circuit 15 that detects the signal, the sub detection circuit 16 that detects the signal at the intermediate connection point 12 of the battery 1, and a signal detected by the main detection circuit 15 and the sub detection circuit 16 indicate a welding failure of the contactor 2. And an arithmetic circuit 9 to be determined. This power supply apparatus can determine the welding of the contactor 2 from the detection signals detected by the sub detection circuit 16 and the main detection circuit 15 in a state in which the contactor 2 is controlled to be turned off. This is because the detection signals detected by the sub detection circuit 16 and the main detection circuit 15 are different between the state in which the contactor 2 is welded and held in the on state and the state in which the contactor 2 is normally switched off. In a state where the contactor 2 is welded and cannot be switched off, the detection signal output from the oscillation circuit 5 is transmitted from the contactor 2 and the load side to the determination circuit 6 in addition to the battery side. 16 and the main detection circuit 15 detect a detection signal transmitted from the battery side and the contactor 2. In this state, the main detection circuit 15 detects shadows of the detection signals on the power supply side and the contactor side, and the sub detection circuit 16 detects signals transmitted mainly from the battery side. In a state where the contactor 2 is switched off with respect to this state, the detection signal is not transmitted to the determination circuit 6 from the contactor side, but is transmitted only from the battery side. Accordingly, the detection signals detected by the main detection circuit 15 and the sub detection circuit 16 differ between the ON state and the OFF state, and the welding of the contactor 2 can be detected by the difference in the detection signals.

  7 also outputs a detection signal on the output side of the oscillation circuit 5 to the line between the positive electrode side of the battery 1 and the first contactor 2A, and the discrimination circuit 6 is connected to the second output line 4B. A differential amplifier 17 for detecting a differential voltage between the signal and the signal at the intermediate connection point 12 of the battery 1 is provided. This power supply device can determine the welding failure of the contactor 2 from the signal detected by the differential amplifier 17. The transmission path of the detection signal output from the oscillation circuit 5 differs between the state in which the contactor 2 is welded and held in the on state and the state in which the contactor 2 is normally switched off, and the second output line 4B This is because the voltage difference between the signal and the signal at the intermediate connection point 12 of the battery 1 is different.

  Further, in the power supply device shown in the circuit diagram of FIG. 8, the output side of the oscillation circuit 5 is connected to the chassis ground 22 of the vehicle via the leakage detection resistor 21. One of the output sides of the oscillation circuit 5 is connected to the positive electrode side of the battery 1 and the first output line 4A. The determination circuit 6 detects the voltage at both ends of the leakage detection resistor 21 to determine a leakage failure in the high voltage line 4. In the power supply device, when the high voltage line 4 is leaked, the high voltage line 4 is connected to the chassis ground 22 via the leak resistance R. In this state, a leakage current flows as shown by a chain line in the figure. This leakage current flows through the leakage detection resistor 21 and generates a voltage at both ends of the leakage detection resistor 21. Therefore, the determination circuit 6 can detect the voltage induced at both ends of the leakage detection resistor 21 to detect the leakage of the high voltage line 4. The smaller the leakage resistance R, the larger the current flowing through the leakage detection resistor 21. Therefore, the leakage resistance R can be detected by detecting the voltage induced in the leakage detection resistor 21.

  Furthermore, the discrimination circuit 6 can detect the non-connected state of the high voltage line 4 by detecting the operating frequency (switching frequency) of the inverter on the vehicle side. This is because, when the inverter on the vehicle side is switched on and off at the operating frequency and is in an operating state, noise at the operating frequency is transmitted to the discrimination circuit 6 via the high voltage line 4.

It is a circuit diagram of the conventional power supply device for vehicles. It is a circuit diagram of the power supply device for vehicles concerning one example of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention. It is a circuit diagram of the power supply device for vehicles concerning other examples of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery 2 ... Contactor 2A ... 1st contactor
2B ... 2nd contactor 3 ... Interlock circuit 4 ... High voltage line 4A ... 1st output line
4B ... 2nd output line 5 ... Oscillator circuit 6 ... Discrimination circuit 7 ... Filter 8 ... A / D converter 9 ... Arithmetic circuit 10 ... Battery unit 11 ... Output connector 12 ... Intermediate connection point 13 ... Coupling capacitor 14 ... Interlock Switch 15 ... Main detection circuit 16 ... Sub detection circuit 17 ... Differential amplifier 18 ... Preamplifier 19 ... Preamplifier 20 ... Earth 21 ... Electrical leakage detection resistor 22 ... Chassis ground 31 ... Battery 32 ... Contactor 33 ... Interlock circuit 34 ... Interlock wire 36 ... Current output circuit 37 ... Current detection circuit 41 ... Output connector 44 ... Interlock switch 45 ... Detection switch 46 ... Output terminal

Claims (10)

The battery (1) is connected to the positive electrode side and the negative electrode side of the battery (1) via the first contactor (2A) and the second contactor (2B) and connected to the vehicle load. Output connector (11) for detachably connecting the voltage line (4) and the disconnection state of the high voltage line (4), and switching the contactor (2) from on to off to output the battery (1) Interlock circuit (3) that shuts off
An oscillator circuit (5) for outputting an AC detection signal to a first output line (4A), which is a line between the first contactor (2A) and the output connector (11); , Connected to the second output line (4B), which is a line between the second contactor (2B) and the output connector (11), and detects a signal transmitted to the second output line (4B). And a discrimination circuit (6) for detecting the disconnection state of the high voltage line (4),
A power supply device for a vehicle in which the discrimination circuit (6) detects a non-connected state of the high voltage line (4) and switches off the contactor (2) to cut off the output of the battery (1).   A plurality of batteries (1) are connected in series at the intermediate connection point (12), and the signal transmitted from the discrimination circuit (6) to the second output line (4B) and the intermediate connection point of the battery (1) The power supply device for a vehicle according to claim 1, wherein the signal of (12) is detected to detect a disconnected state of the high voltage line (4).   A plurality of batteries (1) are connected in series at an intermediate connection point (12), and a determination circuit (6) detects a signal of the second output line (4B), a main detection circuit (15), and a battery ( The sub-detection circuit (16) that detects the signal at the intermediate connection point (12) in (1) and the signals detected by the main detection circuit (15) and the sub-detection circuit (16) The vehicle power supply device according to claim 2, further comprising an arithmetic circuit (9) for determining a connection state.   A plurality of batteries (1) are connected in series at the intermediate connection point (12), and the discrimination circuit (6) is connected to the signal of the second output line (4B) and the intermediate connection point (12) of the battery (1). The vehicle according to claim 2, further comprising a differential amplifier (17) that detects a difference voltage between the two signals and detecting a non-connected state of the high voltage line (4) from a signal detected by the differential amplifier (17) Power supply.   The oscillation circuit (5) has the output side connected to the first output line (4A) and the ground (20), and the discrimination circuit (6) is connected to the second output line (4B) and the ground (20). The power supply device for vehicles described in Claim 1 which has connected the input side to.   The oscillation circuit (5) outputs to the line between the positive electrode side of the battery (1) and the first contactor (2A), and the discrimination circuit (6) is connected to the negative electrode side of the battery (1) and the second contactor ( 2. The power supply device for a vehicle according to claim 1, wherein a signal on the line between 2B) is detected to determine a welding failure of the contactor (2).   A plurality of batteries (1) are connected in series at an intermediate connection point (12), and a determination circuit (6) detects a signal of the second output line (4B), a main detection circuit (15), and a battery ( Sub-detection circuit (16) that detects the signal at the intermediate connection point (12) in (1) and the contact detection failure of the contactor (2) is determined from the signals detected by the main detection circuit (15) and the sub-detection circuit (16) The power supply device for vehicles described in Claim 6 provided with the arithmetic circuit (9) which performs.   A plurality of batteries (1) are connected in series at the intermediate connection point (12), and the discrimination circuit (6) is connected to the signal of the second output line (4B) and the intermediate connection point (12) of the battery (1). A vehicle power source according to claim 6, further comprising a differential amplifier (17) for detecting a difference voltage between the two signals, wherein a welding failure of the contactor (2) is determined from a signal detected by the differential amplifier (17). apparatus.   The oscillation circuit (5) connects the output side to the chassis ground (22) of the vehicle via the leakage detection resistor (21), and the discrimination circuit (6) detects the voltage of the leakage detection resistor (21). The power supply device for a vehicle according to claim 1, wherein an electric leakage failure of the high voltage line (4) is determined. The vehicle power supply device according to claim 1, wherein the discrimination circuit (6) detects the non-connection state of the high voltage line (4) by detecting the operating frequency (switching frequency) of the inverter on the vehicle side.

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