WO2019049698A1 - Power conversion circuit and power conversion device - Google Patents

Abstract

This power conversion device is provided with first and second semiconductor switch elements, an output unit, and a signal processing unit. The first semiconductor switch element includes a first switch portion which is connected in series with a high potential input portion and a connection point between the high potential input portion and the connection point, and a first sense terminal for transmitting a first sense signal corresponding to a current flowing through the first switch portion. The second semiconductor switch element includes a second switch portion which is connected in series with a low potential input portion and the connection point between the low potential input portion and the connection point, and a second sense terminal for transmitting a second sense signal corresponding to a current flowing through the second switch portion. The output unit is connected to the connection point. The current sensor transmits a current detection signal corresponding to an output current flowing through the output unit. The signal processing unit is configured to determine a failure in the current sensor on the basis of the result of comparison of the first sense signal and the current detection signal, and the result of comparison of the second sense signal and the current detection signal. With the power conversion device, anomaly in the current sensor can be easily determined.

Description

POWER CONVERSION CIRCUIT AND POWER CONVERSION DEVICE

The present invention relates to a power converter used in various electronic devices.

FIG. 9 is a circuit block diagram of the conventional power conversion device 1. The power converter 1 supplies three-phase power for driving the three-phase motor 2 to the three-phase motor 2. The power conversion device 1 has a control circuit 3, a gate drive circuit 4, current sensors 6 u, 6 v, 6 w and a power conversion circuit 7. The power conversion circuit 7 has a DC power supply 8, a u-phase conversion circuit 9u, a v-phase conversion circuit 9v, and a w-phase conversion circuit 9w.

Electric power is supplied to the three-phase motor 2 from the u-phase conversion circuit 9 u, the v-phase conversion circuit 9 v, and the w-phase conversion circuit 9 w. The AC power generated by the u-phase conversion circuit 9 u, the v-phase conversion circuit 9 v, and the w-phase conversion circuit 9 w is detected by the current sensors 6 u, 6 v, 6 w as current values and then converted into voltage signals. It is transmitted to the circuit 3. The control circuit 3 causes the u phase conversion circuit 9 u, the v phase conversion circuit 9 v, and the w phase conversion circuit 9 w to output predetermined power in accordance with the current values detected by the current sensors 6 u, 6 v, 6 w. The u-phase conversion circuit 9 u, the v-phase conversion circuit 9 v, and the w-phase conversion circuit 9 w are controlled through the gate drive circuit 4.

When an abnormality occurs in the current sensors 6u, 6v, 6w, a failure may occur in the control of the three-phase motor 2, so that the following failure determination is performed. First, the peak current in the u phase generated by the u phase conversion circuit 9 u is detected by the current sensor 6 u. Next, when the current in the u phase is a peak current, the current sensor 6v detects the current value in the v phase. The control circuit 3 compares the current value of the u phase with the current value of the v phase, and the abnormality of the current sensors 6u and 6v is determined depending on whether the current value of the v phase is half of the current value of the u phase. Determine the presence or absence.

A conventional power converter similar to the power converter 1 is disclosed in, for example, Patent Document 1.

JP, 2015-233371, A

The power converter includes first and second semiconductor switch elements, an output unit, and a signal processing unit. The first semiconductor switch element includes a first switch portion connected in series with the high potential input portion and the connection point between the high potential input portion and the connection point, and a current flowing through the first switch portion And a first sense terminal for transmitting a first responsive sense signal. The second semiconductor switch element includes a second switch portion connected in series to the low potential input portion and the connection point between the low potential input portion and the connection point, and a current flowing through the second switch portion And a second sense terminal for emitting a second sense signal corresponding to the The output unit is connected to the connection point. The current sensor transmits a current detection signal according to the output current flowing through the output unit. The signal processing unit is configured to determine a failure of the current sensor based on a comparison result of the first sense signal and the current detection signal and a comparison result of the second sense signal and the current detection signal. .

This power converter can easily determine the abnormality of the current sensor.

FIG. 1A is a circuit block diagram of a power conversion circuit according to an embodiment. FIG. 1B is an equivalent circuit block diagram of the power conversion circuit shown in FIG. 1A. FIG. 1C is a diagram showing signals in the operation of the power conversion circuit in the embodiment. FIG. 2 is a diagram showing signals in the operation of the power conversion circuit in the embodiment. FIG. 3 is a diagram showing a signal in another operation of the power conversion circuit in the embodiment. FIG. 4 is a circuit block diagram of another power conversion circuit according to the embodiment. FIG. 5 is a circuit block diagram of the three-phase power converter in the embodiment. FIG. 6 is a circuit block diagram of another three-phase power converter in the embodiment. FIG. 7 is a circuit block diagram of still another three-phase power converter according to the embodiment. FIG. 8 is a circuit block diagram of still another three-phase power converter according to the embodiment. FIG. 9 is a circuit block diagram of a conventional power converter.

FIG. 1A is a circuit block diagram of a power conversion circuit 10 according to an embodiment. Power conversion circuit 10 includes a high potential input unit 11, a low potential input unit 12, an upper arm unit 13, a lower arm unit 14, an output unit 15, a current sensor 16, and a signal processing unit 17. . The high DC potential of the DC power supply 24 is applied to the high potential input unit 11. A low DC potential lower than the high DC potential is applied to the low potential input unit 12 from the power supply 24.

The upper arm portion 13 has a semiconductor switch element 18, and the high potential input portion 11 is connected to the high potential side of the upper arm portion 13. The semiconductor switch element 18 is provided with a sense terminal 20, and the sense terminal 20 transmits a sense signal S20. The lower arm portion 14 has a semiconductor switch element 19, and the low potential input portion 12 is connected to the low potential side of the lower arm portion 14. The semiconductor switch element 19 is provided with a sense terminal 21. The sense terminal 21 transmits a sense signal S21.

The output unit 15 is provided at a connection point 115 between the low potential side of the upper arm unit 13 and the high potential side of the lower arm unit 14. Further, the current sensor 16 detects an output current I15 of the output unit 15, and transmits a current detection signal S16 corresponding to the output current.

The signal processing unit 17 is connected to the upper arm 13, the lower arm 14, and the current sensor 16. Signal processing unit 17 receives sense signal S20 transmitted from upper arm unit 13, sense signal S21 transmitted from lower arm unit 14, and current detection signal S16 transmitted from current sensor 16, and sense signal S20. , And S21 are compared with the current detection signal S16. The signal processing unit 17 performs failure determination of the current sensor 16 based on the comparison result of the sense signal S20 and the current detection signal S16 and the comparison result of the sense signal S21 and the current detection signal S16.

With the above configuration and operation, in power conversion circuit 10, each of sense signal S20 reflecting the current output from upper arm unit 13 and sense signal S21 reflecting the current output from lower arm unit 14 are currents The signal processing unit 17 compares the current detection signal S16 detected by the sensor 16 with the signal processing unit 17 to detect the presence or absence of a failure of the current sensor 16. That is, the sense signals S20 and S21 are regarded as a virtual output current reflecting the output current I15 in the output unit 15, and the current detection signal S16 in which the virtual output current is actually detected by the current sensor 16 in the output unit 15 and the signal processing unit 17 Compared by

If the difference between each of the sense signals S20 and S21 compared by the signal processing unit 17 and the current detection signal S16 is within a predetermined range, the signal processing unit 17 determines that the current sensor 16 is normal. . On the other hand, if at least one of the difference between the sense signal S20 and the current detection signal S16 compared by the signal processing unit 17 and the difference between the sense signal S21 and the current detection signal S16 is out of a predetermined range, The signal processing unit 17 determines that the current sensor 16 is abnormal.

FIG. 1B is an equivalent circuit block diagram of the power conversion circuit 10. The semiconductor switch element 18 forms a switch section 118 which is formed between the source terminal 18S and the drain terminal 18D and turned on and off by the signal inputted to the gate terminal 18G. The sense terminal 20 transmits a sense signal S20 according to the current flowing to the switch unit 118. The semiconductor switch element 19 forms a switch section 119 which is formed between the source terminal 19S and the drain terminal 19D and turned on / off by the signal inputted to the gate terminal 19G. The sense terminal 21 transmits a sense signal S21 according to the current flowing to the switch section 119.

In the operation related to the above determination, in the power conversion circuit 10 which outputs single phase power, the power conversion circuit 10 itself determines the presence or absence of an abnormality with respect to the current sensor 16 provided in the power conversion circuit 10. In other words, the power conversion circuit 10 can detect the presence or absence of an abnormality of a single current sensor 16 corresponding to a single phase, instead of comparing the output current across a plurality of phases to detect an abnormality. As a result, as described later, identification of the failed current sensor 16 can be facilitated.

Although the conventional power conversion device 1 shown in FIG. 9 can detect that an abnormality has occurred in any of the current sensors 6u, 6v, 6w, it specifies the current sensor in which the abnormality has occurred among the current sensors 6u, 6v, 6w You can not do it.

Therefore, in order to identify the current sensor in which the abnormality has occurred, it is necessary to arrange the current sensors 6u, 6v, 6w in all of the u phase, v phase, w phase.

As described above, the power conversion circuit 22 in the embodiment can facilitate identification of the failed current sensor 16.

The power conversion circuit 10 includes a high potential input unit 11, a low potential input unit 12, an upper arm unit 13, a lower arm unit 14, an output unit 15, a current sensor 16, and a signal processing unit 17. Including.

The upper arm portion 13 has a semiconductor switch element 18, and the high potential input portion 11 is connected to the high potential side of the upper arm portion 13. In other words, the high potential input unit 11 is connected to the drain terminal 18D side of the semiconductor switch element 18. The semiconductor switch element 18 is provided with a sense terminal 20, and the sense terminal 20 transmits a sense signal S20.

The lower arm portion 14 has a semiconductor switch element 19, and the low potential input portion 12 is connected to the low potential side of the lower arm portion 14. In other words, the low potential input unit 12 is connected to the source terminal 19S side of the semiconductor switch element 19. The semiconductor switch element 19 is provided with a sense terminal 21. The sense terminal 21 transmits a sense signal S21.

Strictly speaking, the sense terminal 20 is a terminal provided branched to the source terminal 18S of the semiconductor switch element 18. A minute current flows separately from the current flowing to the source terminal 18S through the sense terminal 20, and the current values of both do not interfere with each other. The current flowing to the sense terminal 20 and the current flowing to the source terminal 18S exhibit substantially the same characteristics except for the amplitude.

Similarly, the sense terminal 21 is a terminal provided branched to the source terminal 19S of the semiconductor switch element 19. A minute current flows separately from the current flowing to the source terminal 19S through the sense terminal 21, and the current values of both do not interfere with each other. The current flowing to the sense terminal 21 and the current flowing to the source terminal 19S exhibit substantially the same characteristics except for the amplitude.

The output unit 15 is connected to a connection point 115 between the low potential side of the upper arm unit 13 and the high potential side of the lower arm unit 14. In other words, the output unit 15 is connected to the connection point 115 between the source terminal 18S side of the semiconductor switch element 18 and the drain terminal 19D side of the semiconductor switch element 19. Further, the current sensor 16 detects an output current I15 of the output unit 15, and transmits a current detection signal S16 corresponding to the output current I15.

The signal processing unit 17 directly receives a sense signal S20 and a sense signal S21, which are current signals, from the sense terminal 20 of the upper arm unit 13 and the sense terminal 21 of the lower arm unit 14, and Then, the upper arm synchronization signal and the lower arm synchronization signal are generated, and each of the upper arm synchronization signal and the lower arm synchronization signal is compared with the current detection signal S16.

FIG. 1C shows sense signals S20 and S21 and a current detection signal S16. In FIG. 1C, the vertical axis indicates the value of each vibration, and the horizontal axis indicates time. The output unit 15 is connected to an inductive load such as a coil of a motor. The semiconductor switch elements 18 and 19, that is, the switch sections 118 and 119 are alternately repeatedly turned on and off. That is, when the semiconductor switch element 18 (switch section 118) is on, the semiconductor switch element 19 (switch section 119) is off, and when the semiconductor switch element 18 (switch section 118) is off, the semiconductor switch element 19 (switch section) 119) is on. That is, when the semiconductor switch element 19 (switch section 119) is on, the semiconductor switch element 18 (switch section 118) is off, and when the semiconductor switch element 19 (switch section 119) is off, the semiconductor switch element 18 (switch section) 118) is on. By inputting appropriate control signals to the gate terminals 18G and 19G, an output current I15 which is a sine wave flows in the output unit 15 by pulse width modulation (PWM) control.

The sense signals S20 and S21 actually have discontinuous waveforms as shown in FIG. 1C, and the upper side when the switch portion 118 of the upper arm portion 13 or the switch portion 119 of the lower arm portion 14 is turned on. A plurality of trapezoidal pulse waveforms corresponding to the waveform of the current in the arm 13 or the lower arm 14 exist. The width of the trapezoidal pulse waveform of the sense signals S20 and S21 has a value substantially corresponding to the duty ratio of the upper arm 13 or the lower arm 14.

Therefore, the signal processing unit 17 generates an alternating voltage and a synthetic sense signal or a synthetic synchronization signal at the timing when it becomes the apex portion of each trapezoidal pulse waveform or at the timing when it becomes the apex portion of any trapezoidal pulse waveform. Each current detection signal S16 is detected as a waveform and compared. Then, the signal processing unit 17 determines the failure of the current sensor 16.

In other words, the signal processing unit 17 performs the comparison process at a plurality of temporally dispersed timings or at a single timing synchronized with the timing when the composite sense signal or the composite synchronization signal is emitted as a trapezoidal pulse waveform. The failure determination of the current sensor 16 may be performed. The comparison does not need to be performed for all trapezoidal pulse waveforms, and when the sense signals S20 and S21 are regarded as smooth waveforms such as the current detection signal S16, the frequency of comparison is frequently set at the timing when the slope becomes large. In the timing where the inclination is small, the frequency of comparison may be reduced to improve the accuracy of comparison. Here, the output current I15 from the output unit 15 is controlled by adjusting the width of each trapezoidal pulse waveform by PWM control.

FIG. 2 shows sense signals S20 and S21 and a current detection signal S16. FIG. 2 also shows a combined sense signal S22 obtained by combining the sense signals S20 and S21. The signal processing unit 17 generates a combined sense signal S22 obtained by combining the sense signals S20 and S21. FIG. 2 shows the sense signals S20 and S21 as a smooth waveform in which the values at the times of comparison are continuously connected.

The sense signal S21 or the lower arm synchronization signal is a positive voltage signal because the source terminal 19S of the semiconductor switch element 19 has a potential higher than that of the low potential input unit 12. Therefore, when the synthetic sense signal S22 is generated while maintaining the polarity, it becomes a positive voltage signal such as a pulsating current as shown in FIG. On the other hand, since the current detection signal S16 transmitted by the current sensor 16 is obtained by detecting the current supplied from the positive and negative voltages alternately from the upper arm 13 and the lower arm 14, as shown in FIG. It becomes an alternating voltage signal as shown.

In order to easily compare the combined sense signal S22 with the current detection signal S16, the signal processing unit 17 inverts the negative voltage side of the current detection signal S16 to the positive voltage side as indicated by a broken line. Then, the signal processing unit 17 performs failure determination of the current sensor 16 based on the comparison result of the combined sense signal S22 and the current detection signal S16.

FIG. 3 shows signals in another operation of the power conversion circuit 10. In the operation shown in FIG. 3, the combined sense signal S22 is an alternating voltage signal including the broken line shown in FIG. 3 with the polarity of the sense signal S21 inverted to the negative voltage side. Then, the signal processing unit 17 determines the failure of the current sensor 16 based on the comparison result of the combined sense signal S22 and the current detection signal which is an AC voltage.

The method of failure determination of the current sensor 16 will be described below. For example, the signal processing unit 17 compares and stores in advance the relationship between the amplitude of the current detection signal S16 when the current sensor 16 is normal and the amplitude of the combined sense signal S22 as a pre-stage for performing the failure determination. The signal processing unit 17 determines that the current sensor 16 is broken when a difference of a predetermined amount or more occurs between the previously stored relationship and the relationship between the measured current detection signal S16 and the combined sense signal S22. judge.

For example, the signal processing unit 17 stores the ratio R1 and the ratio R2 as initial setting values. The ratio R1 is a ratio of the amplitude V1 of the sense signal S20 shown in FIG. 2 or 3 to the amplitude V3 of the current detection signal S16 when the current sensor 16 is normal. The ratio R2 is a ratio of the amplitude V2 of the sense signal S21 to the amplitude V4 of the current detection signal S16 when the current sensor 16 is normal. When the current sensor 16 is normal, the ratio of the amplitude V1 of the sense signal S20 to the amplitude V3 on the positive side of the current detection signal S16 is a substantially constant value at all times. This value is the ratio R1. Similarly, when the current sensor 16 is normal, the ratio of the amplitude V2 of the sense signal S21 to the amplitude V4 on the negative side of the current detection signal S16 is a substantially constant value at all times. This value is the ratio R2.

The ratio R1 and the ratio R2 of the above-described initial setting values are stored in the signal processing unit 17. When the power conversion circuit 10 is operating, the signal processing unit 17 constantly or at a predetermined timing compares the amplitude V1 of the sense signal S20 with the amplitude V3 on the positive side of the current detection signal S16, and detects the amplitude V2 of the sense signal S21. This is compared with the positive amplitude V4 of the current detection signal S16. When the power conversion circuit 10 is operating, the signal processing unit 17 obtains a ratio R3 to the positive amplitude V3 of the current detection signal S16 of the amplitude V1 of the sense signal S20. Similarly, the signal processing unit 17 obtains a ratio R4 with respect to the negative amplitude V4 of the current detection signal S16 of the amplitude V2 of the sense signal S21.

When current sensor 16 is normal, ratio R3 and ratio R4 obtained when power conversion circuit 10 is operating are ratio R1 and ratio R2 given to power conversion circuit 10 as the initial setting values. And indicate values substantially the same as each other, or indicate values within a predetermined range. However, if there is an abnormality in the current sensor 16, the ratio R3 and the ratio R4 are also different because the values are different from the values indicated by the amplitudes V3 and V4 of the current detection signal S16 when the current sensor 16 is normal. It differs from the value normal to the current sensor 16. Therefore, when the ratio R3 and the ratio R4 indicate values beyond the predetermined range based on the ratio R1 and the ratio R2, the signal processing unit 17 determines that the current sensor 16 has an abnormality.

Further, by connecting an inductive load such as a three-phase motor to the output unit 15, the current I15 flowing through the output unit 15 becomes a continuous signal. Therefore, the current detection signal S16 generated from the current sensor 16 has a continuous waveform unlike the sense signals S20 and S21.

The above trapezoidal pulse waveform is shown in the form which does not consider the body diode in the semiconductor switch elements 18 and 19. Even if it is a pulse waveform in consideration of a body diode, the timing of detecting and comparing the synthesized sense signal S22 and the current detection signal S16 which is an alternating voltage as each waveform is the same as the case described above. is there. In this case, the pulse waveform has a signal waveform which gradually decreases from the top of the trapezoidal shape.

In the power conversion circuit 10 outputting power of a single phase by the operation related to the failure determination with respect to the current sensor 16, the power conversion circuit 10 itself is abnormal with respect to the current sensor 16 provided in the power conversion circuit 10. Determine the presence or absence. In other words, the power conversion circuit 10 can detect the presence or absence of an abnormality of a single current sensor 16 corresponding to a single phase, instead of comparing the output current across a plurality of phases to detect an abnormality. As a result, identification of the failed current sensor 16 can be facilitated.

In the above embodiment, the signal processing unit 17 compares and determines for convenience of the operation description. Therefore, the signal processing unit 17 may compare the signals and the control circuit 25 may make a determination on the current sensor 16. A control circuit may be provided as a function to perform comparison and determination, and a function to collectively control the power conversion circuit 10 and the entire three-phase power conversion device. In other words, the control circuit may include a signal processing unit 17 and a gate drive circuit that supplies signals to the gate terminals 18G and 19G to drive the semiconductor switch elements 18 and 19.

Further, FETs (field effect transistors) are applied to the upper arm portion 13 and the lower arm portion 14 as the semiconductor switch element 18 and the semiconductor switch element 19 in the drawing. A bipolar transistor such as an IGBT (insulated gate bipolar transistor) may be applied to the semiconductor switch element 18 and the semiconductor switch element 19.

Here, when a MOSFET (metal oxide semiconductor field effect transistor) is applied as the semiconductor switch element 18 and the semiconductor switch element 19 to the upper arm portion 13 and the lower arm portion 14, the semiconductor switch element 18 and the semiconductor switch element 19. It is possible to make the sense signals S20 and S21 approximate to the current I15 flowing to the output unit 15 by using the characteristic that allows the backward current to flow. Details will be described below.

In FIGS. 2 and 3 described above, the upper arm synchronization signal and the lower arm synchronization signal of the upper arm 13 and the lower arm 14 are transmitted from the drain terminal 18D of the semiconductor switch element 18 to the source terminal 18S, and It is a signal obtained when forward current flows from the drain terminal 19D of the switch element 19 to the source terminal 19S. On the other hand, when a reverse current flows from the source terminal 18S to the drain terminal 18D of the semiconductor switch element 18 and a reverse current flows from the source terminal 19S to the drain terminal 19D of the semiconductor switch element 19 The upper arm synchronization signal and the lower arm synchronization signal may be generated by further use.

In other words, the upper arm synchronization signal (sense signal S20) and the lower arm synchronization signal (sense signal S21) of the upper arm 13 and the lower arm 14 shown in FIG. This is a signal obtained when the on-duty ratio of the semiconductor switch element 19 is large. On the other hand, the upper arm synchronization signal and the lower arm synchronization signal may be generated by further using a signal obtained when the on-duty ratio in the semiconductor switch element 18 and the semiconductor switch element 19 is small.

The upper arm portion 13 and the lower arm portion 14 basically alternately turn on and off to operate. Here, when the output current waveform is in the positive polarity region, the on-duty ratio of the upper arm 13 is larger than the on-duty ratio of the lower arm 14, and the upper waveform is the maximum value. The on-duty ratio of 13 is also the largest. Then, when the output current waveform is in the region of positive polarity, when the upper arm portion 13 is turned on, forward current flows through the semiconductor switching device 18 and the forward current flowing through the semiconductor switching device 18 is handled. The sense signal S20 or the upper arm synchronization signal is issued from the sense terminal 20 or the upper arm unit 13 to the signal processing unit 17.

Here, in particular, when an inductive load is connected to the output unit 15 like a three-phase motor, when the lower arm unit 14 is turned on when the waveform of the output current I15 is in the positive polarity region, A reverse current flows in the semiconductor switch element 19 due to the induced power by the inductive load. Therefore, a sense signal S21 or lower arm synchronization signal corresponding to the reverse current flowing in the semiconductor switch element 19 is issued from the sense terminal or lower arm unit 14 to the signal processing unit 17. As described above, since the upper arm 13 and the lower arm 14 basically alternately repeat ON and OFF, the upper arm synchronization signal corresponding to the forward current and the lower side corresponding to the reverse current The arm synchronization signal is alternately issued to the signal processing unit 17. At this time, the polarities of the upper arm synchronization signal and the lower arm synchronization signal are reversed corresponding to the direction of the current.

Therefore, when the output current waveform is in the positive polarity region, the upper arm is constituted by a plurality of pulses whose width is wider than the lower arm synchronization signal in proportion to the on-duty ratio of the upper arm portion 13 There are both synchronization signals and a lower arm synchronization signal composed of a plurality of pulses of narrower width and opposite polarity compared to the upper arm synchronization signal. Then, the signal processing unit 17 receives both signals.

When the output current waveform is in the positive polarity region, the polarity of the lower arm synchronization signal at the on duty of the lower arm portion 14 is inverted to the upper arm synchronization signal at the on duty of the upper arm portion 13 The synthesized waveform obtained by interpolation and addition approximates the waveform of the current I15 flowing to the output unit 15. As a result of this, the waveform obtained by interpolating the lower arm synchronization signal to the upper arm synchronization signal and the current detection signal S16 which is an AC voltage are detected as waveforms, respectively, and the determination is made by comparing the failure detection of the current sensor 16 Accuracy is improved.

When the waveform of the output current I15 is in the negative polarity region, the on-duty ratio of the lower arm unit 14 is larger than the on-duty ratio of the upper arm unit 13, and the current waveform has a minimum value. The on-duty ratio of the side arm portion 14 also becomes maximum. When the waveform of the output current I15 is in the negative polarity region, when the lower arm portion 14 is turned on, forward current flows through the semiconductor switch element 19 and forward current flows through the semiconductor switch element 19 A sense signal S21 corresponding to the current or a lower arm synchronization signal is issued from the sense terminal 21 or the lower arm unit 14 to the signal processing unit 17.

In the same manner as described above, when the inductive load is connected to the output unit 15 like a three-phase motor, induction is performed when the upper arm unit 13 is turned on when the output current waveform is in the negative polarity region. Reverse current flows in the semiconductor switch element 18 due to the induced power by the load. Therefore, a sense signal S20 or an upper arm synchronization signal corresponding to the reverse current flowing to the semiconductor switch element 18 is issued from the sense terminal 20 or the upper arm unit 13 to the signal processing unit 17. Also here, since the upper arm unit 13 and the lower arm unit 14 basically alternately turn on and off repeatedly, the lower arm synchronization signal corresponding to the forward current and the upper arm synchronization corresponding to the reverse current The signal is alternately issued to the signal processing unit 17. At this time, the lower arm synchronization signal and the upper arm synchronization signal are in a state in which the polarity is inverted in accordance with the direction of the current.

Therefore, when the waveform of the output current I15 is in the negative polarity region, a lower arm synchronization signal composed of a plurality of pulses whose width is wider than the upper arm synchronization signal in proportion to the on duty ratio; There are both signals with the upper arm synchronization signal constituted by a plurality of pulses whose width is narrower and opposite in polarity to the lower arm synchronization signal in proportion to the on duty ratio. Then, the signal processing unit 17 receives both signals.

When the waveform of the output current I15 is in the negative polarity region, the upper arm synchronization signal at the on duty of the upper arm unit 13 is inverted in polarity to the lower arm synchronization signal at the on duty of the lower arm unit 14 The synthesized waveform obtained by the interpolation and addition above approximates the waveform of the current flowing to the output unit 15. As a result, a waveform obtained by interpolating the upper arm synchronization signal to the lower arm synchronization signal and the current detection signal which is an AC voltage are detected as waveforms, respectively, and the determination accuracy is determined by comparing the failure detection of the current sensor 16 Improve.

FIG. 4 is a circuit block diagram of another power conversion circuit 10a according to the embodiment. In FIG. 4, the same parts as those of the power conversion circuit 10 shown in FIGS. 1A and 1B are denoted by the same reference numerals.

Power conversion circuit 10 a includes a conversion circuit 27 connected in series to sense terminal 20 and source terminal 18 S of semiconductor switch element 18, a conversion connected in series to sense terminal 21 and source terminal 19 S of semiconductor switch element 19. And a circuit 28.

The signal processing unit 17 is connected to the upper arm 13, the lower arm 14, and the current sensor 16. Then, the signal processing unit 17 controls the upper arm synchronization signal (sense signal S20) corresponding to the potential difference between both ends of the conversion circuit 27 transmitted from the upper arm unit 13, and both ends of the conversion circuit 28 transmitted from the lower arm unit 14. A lower arm synchronization signal (sense signal S21) corresponding to the potential difference between the two, and a current detection signal S16 transmitted from the current sensor 16 by converting the current into a voltage. The signal processing unit 17 compares the upper arm synchronization signal (sense signal S20) with the current detection signal, and compares the lower arm synchronization signal (sense signal S21) with the current detection signal S16.

In the above, the power conversion circuit 10, 10a which detects the presence or absence of abnormality of the single current sensor 16 corresponding to a single phase and specifies the failed current sensor 16 has been described. Further, as described below, the number of current sensors 16 in the three-phase power converter can be determined using the ability to detect the presence or absence of a single current sensor 16 corresponding to a single phase. It can also be reduced. And as a result, size reduction and weight reduction of a three-phase power converter are attained.

The power converter using the power converter circuit 10 will be described below. FIG. 5 is a circuit block diagram of the three-phase power conversion device 22 in the embodiment.

As shown in FIG. 5, the three-phase power conversion device 22 has power conversion circuits 10 u, 10 v, and 10 w for supplying power to the three-phase motor 23. The power conversion circuits 10 u, 10 v and 10 w respectively supply u-phase power, v-phase power and w-phase power to the three-phase motor 23. The configuration of each of the power conversion circuits 10 u, 10 v and 10 w is the same as the power conversion circuit 10 described above, and the power conversion circuit 10 in the three-phase power conversion device 22 operates by operating with different phases. It operates as 10v and 10w.

The three-phase power converter 22 also has a DC power supply 24, a control circuit 25 and a gate drive circuit 26. The DC power supply 24 supplies DC power of high potential to the high potential input unit 11 in the power conversion circuits 10 u, 10 v, 10 w. Further, the direct current power supply 24 supplies high potential direct current power to the low potential input unit 12 in the power conversion circuits 10 u, 10 v, 10 w.

The signal processing units 17 u, 17 v, and 17 w in the power conversion circuits 10 u, 10 v, and 10 w of the u-phase, v-phase, and w-phase are connected to the control circuit 25. Then, the signal processing units 17u, 17v, 17w detect the presence or absence of abnormality in the current sensor 16 as described above, and simultaneously detect the output current and the output voltage in the output unit 15 of each phase, and detect the detection result signal As the control circuit 25. The control circuit 25 transmits an operation control signal to the gate drive circuit 26 to control the output current and the output voltage so that the three-phase motor 23 operates in a desired state. Further, the gate drive circuit 26 drives the upper arm 13 and the lower arm 14 of each phase of the power conversion circuits 10 u, 10 v, 10 w based on the operation control signal. The control circuit 25 includes an operation unit and a storage unit, and the gate drive circuit 26 generates a PWM signal corresponding to a control signal from the control circuit 25. The upper arm unit 13 and the lower arm unit 14 receive PWM signals etc. Driven by

FIG. 6 is a circuit block diagram of another three-phase power converter 22a in the embodiment. 6, the same reference numerals as in the three-phase power converter 22 shown in FIG. 5 denote the same parts. The three-phase power conversion device 22a includes a DC power supply 24, a power conversion circuit 10u corresponding to a first phase, a power conversion circuit 10v corresponding to a second phase, a power conversion circuit 10w corresponding to a third phase, and control And a circuit 25. Here, as an example, the first phase is described to correspond to the u phase, the second phase to the v phase, and the third phase to the w phase, but the first phase, the second phase, the third phase and the u phase, Correspondence with v phase and w phase does not depend on the above-mentioned form.

The power conversion circuits 10u, 10v, and 10w of the first phase, the second phase, and the third phase respectively include the upper arm unit 13, the lower arm unit 14, the output unit 15, and the signal processing unit 17 (17u, 17 v, 17 w). The upper arm unit 13 has a semiconductor switch element 18 whose high potential side is connected to the high potential input unit 11 connected to the DC power supply 24 and a sense terminal 20 for transmitting a sense signal. The lower arm unit 14 has a low potential side connected to the low potential input unit 12 connected to the DC power supply 24 and has a semiconductor switch element 19 and a sense terminal 21 for transmitting a sense signal. The output unit 15 is provided at a connection point 115 between the low potential side of the upper arm unit 13 and the high potential side of the lower arm unit 14. The signal processing units 17u, 17v, and 17w are connected to the upper arm unit 13 and the lower arm unit 14, and receive the sense signals S20 and S21.

Each of the power conversion circuits 10 u and 10 v has a current sensor 16. The current sensor 16 is connected to the signal processing units 17 u and 17 v, detects an output current of the output unit 15, and transmits a current detection signal corresponding to the output current to the signal processing unit 17.

The control circuit 25 is connected to the signal processing units 17u, 17v, and 17w, and performs failure determination for the current sensor 16, detection of output of the power conversion circuits 10u, 10v, and 10w, and control of the power conversion circuits 10u, 10v, and 10w. Do. With regard to the current sensor 16 of the power conversion circuit 10u, the failure determination for the current sensor 16 in the control circuit 25 includes the sense signals S20 and S21 in the power conversion circuit 10u and the current detection signal by the current sensor 16 in the power conversion circuit 10u. It is performed based on the comparison result with S16. The current sensor 16 of the power conversion circuit 10v is performed based on the comparison result between each of the sense signals S20 and S21 in the power conversion circuit 10v and the current detection signal S16 by the current sensor 16 in the power conversion circuit 10v. The power conversion circuit 10 w does not have a current sensor.

The output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10u is the phase current Ius. The output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10v is the phase current Ivs. The output current I15 obtained by the current sensor 16 in the power conversion circuit 10u is the phase current Iu. The output current I15 obtained by the current sensor 16 in the power conversion circuit 10v is the phase current Iv. Then, the control circuit 25 determines the difference between the phase currents Ius and Iu and the difference between the phase currents Ivs and Iv. When the above difference is within the predetermined range, the control circuit 25 determines that the current sensor 16 in each phase, here, the current sensor 16 in the power conversion circuit 10 u or the current sensor 16 in the power conversion circuit 10 v is normal. .

In the three-phase alternating current, there is no abnormality in the power conversion operation of the power conversion circuits 10u, 10v, 10w, or no short circuit or ground fault occurs in the power supply and distribution path. The sum of the phase currents of the two is zero. Therefore, the phase current Iw which is the output current I15 in the power conversion circuit 10w not using the current sensor 16 can be obtained as the current detection calculation value according to the following relationship.

Iw = 0-Iu-Iv
Therefore, the control circuit 25 can easily identify the failed current sensor 16, and control the power conversion circuit 10w not using the current sensor to a desired operation state as in the power conversion circuits 10u and 10v. Can. Thereby, the number of current sensors 16 in the three-phase power conversion device 22a can also be reduced. And as a result, size reduction and weight reduction of three-phase power converter 22a are attained.

Here, although the determination by the control circuit 25 is described using the current value, as described above in the detailed description of the individual power conversion circuit 10, after the current value is voltage-converted, the control circuit 25 is described. May make the determination.

FIG. 7 is a circuit block diagram of still another three-phase power conversion device 22b in the embodiment. In FIG. 7, the same parts as those of the three-phase power conversion device 22b shown in FIG. 5 and FIG. It is also possible to reduce the number of current sensors 16 in the three-phase power conversion device 22b after reducing the sense terminal 20 and the sense terminal 21 and simplifying the calculation and control in the signal processing units 17u, 17v, 17w and the control circuit 25. it can.

The three-phase power conversion device 22b includes a DC power supply 24, a power conversion circuit 10u corresponding to a first phase, a power conversion circuit 10v corresponding to a second phase, a power conversion circuit 10w corresponding to a third phase, and control And a circuit 25. The power conversion circuits 10u, 10v, and 10w of the first phase, the second phase, and the third phase respectively include the upper arm unit 13, the lower arm unit 14, the output unit 15, and the signal processing unit 17 (17u, 17 v, 17 w). Here, as an example, the first phase is described to correspond to the u phase, the second phase to the v phase, and the third phase to the w phase, but the first phase, the second phase, the third phase and the u phase, Correspondence with v phase and w phase does not depend on the above-mentioned form.

In the power conversion circuits 10 u and 10 v, the upper arm unit 13 includes the semiconductor switch element 18 whose high potential side is connected to the high potential input unit 11 connected to the DC power supply 24 and the sense terminal 20 which transmits the sense signal S 20. Have. Similarly, in the power conversion circuits 10u and 10v, the lower arm unit 14 is connected on the low potential side to the low potential input unit 12 connected to the DC power supply 24, and sense terminals for transmitting the semiconductor switch element 19 and the sense signal S21. And 21.

In the power conversion circuit 10 w, the upper arm unit 13 has the semiconductor switch element 18 whose high potential side is connected to the high potential input unit 11 connected to the DC power supply 24 and does not have the sense terminal 20. Similarly, in the power conversion circuit 10w, the lower arm unit 14 has a low potential side connected to the low potential input unit 12 connected to the DC power supply 24, has a semiconductor switch element 19, and has a sense terminal 21. Not.

In each of the power conversion circuits 10 u, 10 v, 10 w, the output unit 15 is provided at a connection point 115 between the low potential side of the upper arm unit 13 and the high potential side of the lower arm unit 14. In each of power conversion circuits 10u and 10v, signal processing units 17u and 17v are connected to upper arm unit 13 and lower arm unit 14, and in power conversion circuits 10u and 10v, signal processing units 17u and 17v receive sense signals. S20 and S21 are received.

Each of the power conversion circuits 10 u and 10 w has a current sensor 16. The current sensor 16 is connected to the signal processing units 17u and 17w of the power conversion circuits 10u and 10w, detects the output current of the output unit 15, and detects a current detection signal corresponding to the output current as the signal processing units 17u and 17w. Send to

The control circuit 25 is connected to the signal processing units 17u, 17v, and 17w, and performs failure determination for the current sensor 16, detection of output of the power conversion circuits 10u, 10v, and 10w, and control of the power conversion circuits 10u, 10v, and 10w. Do. For the current sensor 16 of the power conversion circuit 10u, the failure determination for the current sensor 16 in the control circuit 25 is performed between the sense signal and the sense signal in the power conversion circuit 10u and the current detection signal by the current sensor 16 in the power conversion circuit 10u. It is performed based on the comparison result. Regarding current sensor 16 of power conversion circuit 10w, sense operation values S20c and S21c respectively corresponding to sense signals S20 and S21 in power conversion circuit 10w and current detection signal S16 by current sensor 16 in power conversion circuit 10w. Based on the comparison result, failure determination of the current sensor 16 of the power conversion circuit 10 w is performed.

Here, the output current obtained by the sense signals S20 and S21 in the power conversion circuit 10u is the phase current Ius, and the output current I15 obtained by the sense operation values S20c and S21c in the power conversion circuit 10w is the phase current Iwc. The output current obtained by the current sensor 16 in the power conversion circuit 10u is the phase current Iu, and the output current I15 obtained by the current sensor 16 in the power conversion circuit 10w is the phase current Iw. The difference between the phase currents Ius and Iu and the difference between the phase currents Iwc and Iw are determined by the control circuit 25. When the above difference is within the predetermined range, the control circuit 25 determines that the current sensors in the respective phases, here, the current sensor 16 in the power conversion circuit 10 u and the current sensor 16 in the power conversion circuit 10 w are normal.

The sense operation values S20c and S21c are obtained using the relationship in which the sum of all the phase voltages of the three-phase alternating current and the sum of all the phase currents described above are zero.

In the power conversion circuits 10 u and 10 v, the signal processing unit 17 receives the sense signal S 20 and the sense signal S 21 from the sense terminal 20 and the sense terminal 21, respectively. The output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10u is the phase current Ius. The output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10v is the phase current Ivs. The operation value Iwc of the phase current obtained as the sense operation values S20c and S21c is obtained by the following relationship.

Iwc = 0-Ius-Ivs
Therefore, in the power conversion circuit 10 w having neither the sense terminal 20 nor the sense terminal 21, the control circuit 25 can detect the presence or absence of abnormality of the current sensor 16 used for the power conversion circuit 10 w. Becomes easy. Further, the phase current Iv in the power conversion circuit 10v having no current sensor can be obtained as the current detection calculation value according to the following relationship as described above.

Iv = 0-Iu-Iw
Therefore, the power conversion circuit 10v having no current sensor can be controlled to a desired operating state as in the power conversion circuits 10u and 10w. Thereby, the number of current sensors 16 in the three-phase power conversion device 22b can also be reduced. And as a result, size reduction and weight reduction of the three-phase power converter 22b are attained.

In other words, even if one of the three phases, the phase without the sense terminal 20 and the phase without the sense terminal 21 and the phase without the current sensor 16, can easily identify the failed current sensor 16 In addition, the number of current sensors 16 can be reduced, and the size and weight of the three-phase power conversion device 22b can be reduced. Here, the phase without the sense terminal 20 and the sense terminal 21 is different from the phase without the current sensor 16.

FIG. 8 is a circuit block diagram of still another three-phase power conversion device 22c in the embodiment. In FIG. 8, the same reference numerals as in the three-phase power conversion devices 22, 22 a and 22 b shown in FIGS. 5 to 7 denote the same parts. The number of current sensors 16 in the three-phase power conversion device 22c after simplifying the calculation and control in the signal processing units 17u, 17v, 17w and the control circuit 25 with only one phase including the sense terminal 20 and the sense terminal 21. Can also be reduced.

The three-phase power conversion device 22c includes a DC power supply 24, a power conversion circuit 10u corresponding to a first phase, a power conversion circuit 10v corresponding to a second phase, a power conversion circuit 10w corresponding to a third phase, and control And a circuit 25. The power conversion circuits 10u, 10v, and 10w of the first phase, the second phase, and the third phase are respectively the upper arm unit 13, the lower arm unit 14, the output unit 15, and the signal processing units 17u, 17v, And 17w. Here, as an example, the first phase is described to correspond to the u phase, the second phase to the v phase, and the third phase to the w phase, but the first phase, the second phase, the third phase and the u phase, Correspondence with v phase and w phase does not depend on the above-mentioned form.

In power conversion circuit 10u, upper arm unit 13 has semiconductor switch element 18 whose high potential side is connected to high potential input unit 11 connected to DC power supply 24, and sense terminal 20 for transmitting sense signal S20. . Similarly, in the power conversion circuit 10u, the lower arm unit 14 has a low potential side connected to the low potential input unit 12 connected to the DC power supply 24, and the sense terminal 21 transmits the semiconductor switch element 19 and the sense signal S21. And.

In the power conversion circuits 10v and 10w, the upper arm unit 13 has the semiconductor switch element 18 whose high potential side is connected to the high potential input unit 11 connected to the DC power supply 24 and has the sense terminal 20. Absent. Similarly, in the power conversion circuits 10v and 10w, the lower arm unit 14 is connected on the low potential side to the low potential input unit 12 connected to the DC power supply 24 and has a semiconductor switch element 19. I do not have it.

In each of the power conversion circuits 10 u, 10 v, 10 w, the output unit 15 is provided at a connection point 115 between the low potential side of the upper arm unit 13 and the high potential side of the lower arm unit 14. In the power conversion circuit 10u, the signal processing unit 17u is connected to the upper arm unit 13 and the lower arm unit 14, and in the power conversion circuit 10u, the signal processing unit 17 receives the sense signals S20 and S21.

Each of the power conversion circuits 10 v and 10 w has a current sensor 16. The current sensor 16 is connected to the signal processing units 17v and 17w of the power conversion circuits 10v and 10w, detects the output current of the output unit 15, and detects a current detection signal corresponding to the output current as the signal processing units 17v and 17w. Send to

The control circuit 25 is connected to the signal processing units 17u, 17v, and 17w, and performs failure determination for the current sensor 16, detection of output of the power conversion circuits 10u, 10v, and 10w, and control of the power conversion circuits 10u, 10v, and 10w. Do. The failure determination for the current sensor 16 in the control circuit 25 can be performed by detecting the sense signals S20 and S21 in the power conversion circuit 10u and the current in the power conversion circuit 10v with respect to the current sensor 16 of either the power conversion circuit 10v or the power conversion circuit 10w. This is performed based on the sum of the three values of the current detection signal S16 by the sensor 16, the current detection signal S16 by the current sensor 16 in the power conversion circuit 10w, and the like.

Here, the output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10u is the phase current Ius. Further, an output current I15 obtained by the current sensor 16 in the power conversion circuit 10v is a phase current Iv. The output current I15 obtained by the current sensor 16 in the power conversion circuit 10w is the phase current Iw. Then, the sum of the phase currents Ius, Iv, Iw is obtained by the control circuit 25. If the above difference is within a predetermined range, control circuit 25 determines that current sensor 16 in each phase, here, current sensor 16 in power conversion circuit 10 v and current sensor 16 in power conversion circuit 10 w are normal. to decide.

Here too, the following relationship is obtained using the relationship in which the sum of all phase voltages of the three-phase alternating current and the sum of all phase currents described above are zero.

Ius + Iv + Iw = 0
When the above value is in the range of values close to 0, the control circuit 25 can easily determine that the specified current sensor 16 is either the power conversion circuit 10v or the power conversion circuit 10w. It becomes possible. Further, the power conversion circuit 10 u having no current sensor can be controlled to a desired operating state in the same manner as the power conversion circuits 10 v and 10 w.

Further, the above relationship is the same as the phase current in the power conversion circuit 10 u not using the current sensor, using the relationship in which the sum of all the phase voltages of the three-phase alternating current and the sum of all the phase currents is zero. Iu is obtained by the following relationship as a current detection calculation value.

Iu = 0-Iv-Iw
The power conversion circuit 10 w having no current sensor as the current detection calculation value can be controlled to a desired operating state as in the power conversion circuits 10 v and 10 w. Here, the output current I15 obtained by the sense signals S20 and S21 in the power conversion circuit 10u is the phase current Ius. When the difference between the phase currents Ius and Iu is within a predetermined range, it is assumed that the current sensor 16 in the first phase, in this case, the current sensor 16 in the power conversion circuit 10v, and both current sensors 16 in the power conversion circuit 10w are normal. The control circuit 25 makes a determination. Thereby, the number of current sensors 16 in the three-phase power conversion device 22c can also be reduced. And as a result, size reduction and weight reduction of the three-phase power converter 22c are attained.

In other words, narrowing down of the current sensor 16 which has failed even if one phase has two phases without the sense terminal 20 and the sense terminal 21 among the three phases and a phase without the current sensor 16 is This can be easily achieved, and the number of current sensors 16 can be reduced, so that the size and weight of the three-phase power conversion device 22c can be reduced. Here, the phase without the sense terminal 20 and the sense terminal 21 and the phase without the current sensor 16 are different phases.

The power conversion circuit of the present invention can easily identify a failed current sensor and is useful in various electronic devices.

10, 10a power conversion circuit 10 u power conversion circuit (first power conversion circuit)
10v power converter (second power converter)
10w power converter (third power converter)
11 high potential input section 12 low potential input section 13 upper arm section 14 lower arm section 15 output section 16 current sensor 17 signal processing section 17u, 17v, 17w signal processing section 18 semiconductor switch element 18D drain terminal 18S source terminal 19 semiconductor switch Element 19D Drain terminal 19S Source terminal 20 Sense terminal 21 Sense terminal 22 Power converter 23 Three-phase motor 24 DC power supply 25 Control circuit 26 Gate drive circuit 27 Conversion circuit (first conversion circuit)
28 converter (second converter)

Claims (13)

1. A high potential input unit to which a high DC potential is applied;
   A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
   A first switch unit connected in series to the high potential input unit and the connection point between the high potential input unit and the connection point, and a first switch corresponding to a current flowing through the first switch unit A first semiconductor switch element having a first sense terminal for transmitting a sense signal;
   A second switch unit connected in series to the low potential input unit and the connection point between the low potential input unit and the connection point, and a second according to a current flowing through the second switch unit A second semiconductor switch element having a second sense terminal for emitting a sense signal of
   An output connected to the connection point;
   A current sensor that generates a current detection signal according to an output current flowing through the output unit;
   A signal configured to determine failure of the current sensor based on the comparison result of the first sense signal and the current detection signal, and the comparison result of the second sense signal and the current detection signal. A processing unit,
   Power converter circuit with.
2. The signal processing unit
   A combined sense signal is obtained by combining the first sense signal and the second sense signal,
   The failure of the current sensor is determined based on the comparison result obtained by comparing the combined sense signal and the current detection signal after making the polarities match.
   The power conversion circuit according to claim 1, wherein the power conversion circuit is configured as follows.
3. The signal processing unit
   When the difference between the combined sense signal and the current detection signal is within a predetermined range, it is determined that the current sensor has not failed.
   When the difference between the combined sense signal and the current detection signal is not within the predetermined range, it is determined that the current sensor is broken.
   The power conversion circuit according to claim 2, wherein the power conversion circuit is configured as follows.
4. The signal processing unit
   When the ratio between the combined sense signal and the current detection signal is within a predetermined range, it is determined that the current sensor has not failed.
   When the ratio between the combined sense signal and the current detection signal is not within the predetermined range, it is determined that the current sensor is broken.
   The power conversion circuit according to claim 2, wherein the power conversion circuit is configured as follows.
5. The signal processing unit
   When the difference between the first sense signal and the current detection signal and the difference between the second sense signal and the current detection signal are within a predetermined range, it is determined that the current sensor has not failed. ,
   The current sensor is broken when at least one of the difference between the first sense signal and the current detection signal and the difference between the second sense signal and the current detection signal is not within the predetermined range. To determine that
   The power conversion circuit according to claim 1, wherein the power conversion circuit is configured as follows.
6. The signal processing unit
   When the ratio of the first sense signal to the current detection signal and the ratio of the second sense signal to the current detection signal are within a predetermined range, it is determined that the current sensor has not failed. ,
   The current sensor is broken when at least one of the ratio between the first sense signal and the current detection signal and the ratio between the second sense signal and the current detection signal is not within the predetermined range. To determine that
   The power conversion circuit according to claim 1, wherein the power conversion circuit is configured as follows.
7. A first conversion circuit which converts the first sense signal into a first voltage and transmits the voltage;
   A second conversion circuit which converts the second sense signal into a second voltage and transmits the second voltage;
   And further
   The signal processing unit may determine the failure of the current sensor based on a comparison result of the first voltage and the current detection signal and a comparison result of the second voltage and the current detection signal. The power conversion circuit according to any one of claims 1 to 6, which is configured.
8. A high potential input unit to which a high DC potential is applied;
   A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
   A first power conversion circuit connected to the high potential input unit and the low potential input unit to output a first output current;
   A second power conversion circuit connected to the high potential input unit and the low potential input unit to output a second output current;
   A third power conversion circuit connected to the high potential input unit and the low potential input unit to output a third output current;
   A control circuit that controls the first power conversion circuit, the second power conversion circuit, and the third power conversion circuit;
   Equipped with
   The first power conversion circuit is
   A first switch connected in series with the high potential input and the first connection between the high potential input and the first connection, and a current flowing through the first switch A first semiconductor switch element having a first sense terminal for emitting a first sense signal according to
   A second switch connected in series with the low potential input and the first connection between the low potential input and the first connection, and a current flowing through the second switch A second semiconductor switch element having a second sense terminal for transmitting a second sense signal according to the current;
   A first output connected to the first connection point for outputting the first output current;
   A first current sensor for emitting a first current detection signal according to the first output current;
   Have
   The second power conversion circuit is
   A third switch connected in series with the high potential input and the second connection between the high potential input and the second connection, and a current flowing through the third switch A third semiconductor switch element having a third sense terminal for transmitting a third sense signal according to
   It flows into the 4th switch part connected in series with the low potential input part and the 2nd connection point between the low potential input part and the 2nd connection point, and flows into the 4th switch part A fourth semiconductor switch element having a fourth sense terminal for transmitting a fourth sense signal according to the current;
   A second output connected to the second connection point for outputting the second output current;
   A second current sensor transmitting a second current detection signal according to the second output current;
   The third power conversion circuit is
   A fifth switch connected in series with the high potential input and the third connection between the high potential input and the third connection, and a current flowing through the fifth switch A fifth semiconductor switch element having a fifth sense terminal for transmitting a fifth sense signal according to
   It flows in the 6th switch part connected in series with the low potential input part and the 3rd connection point between the low potential input part and the 3rd connection point, and flows into the 6th switch part A sixth semiconductor switch element having a sixth sense terminal for transmitting a sixth sense signal according to the current;
   A third output unit connected to the third connection point for outputting the third output current;
   A third current sensor for transmitting a third current detection signal according to the third output current;
   Have
   The control circuit
   Failure of the first current sensor based on the comparison result of the first sense signal and the first current detection signal, and the comparison result of the second sense signal and the first current detection signal To determine
   Failure of the second current sensor based on the comparison result of the third sense signal and the second current detection signal and the comparison result of the fourth sense signal and the second current detection signal To determine
   Failure of the third current sensor based on the comparison result of the fifth sense signal and the third current detection signal and the comparison result of the sixth sense signal and the third current detection signal To determine
   A power converter that is configured to:
9. A high potential input unit to which a high DC potential is applied;
   A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
   A first power conversion circuit connected to the high potential input unit and the low potential input unit to output a first output current;
   A second power conversion circuit connected to the high potential input unit and the low potential input unit to output a second output current;
   A third power conversion circuit connected to the high potential input unit and the low potential input unit to output a third output current;
   A control circuit that controls the first power conversion circuit, the second power conversion circuit, and the third power conversion circuit;
   Equipped with
   The first power conversion circuit is
   A first switch connected in series with the high potential input and the first connection between the high potential input and the first connection, and a current flowing through the first switch A first semiconductor switch element having a first sense terminal for emitting a first sense signal according to
   A second switch connected in series with the low potential input and the first connection between the low potential input and the first connection, and a current flowing through the second switch A second semiconductor switch element having a second sense terminal for transmitting a second sense signal according to the current;
   A first output connected to the first connection point for outputting the first output current;
   A first current sensor for emitting a first current detection signal according to the first output current;
   Have
   The second power conversion circuit is
   A third switch connected in series with the high potential input and the second connection between the high potential input and the second connection, and a current flowing through the third switch A third semiconductor switch element having a third sense terminal for transmitting a third sense signal according to
   It flows into the 4th switch part connected in series with the low potential input part and the 2nd connection point between the low potential input part and the 2nd connection point, and flows into the 4th switch part A fourth semiconductor switch element having a fourth sense terminal for transmitting a fourth sense signal according to the current;
   A second output connected to the second connection point for outputting the second output current;
   A second current sensor transmitting a second current detection signal according to the second output current;
   The third power conversion circuit is
   A fifth switch connected in series with the high potential input and the third connection between the high potential input and the third connection, and a current flowing through the fifth switch A fifth semiconductor switch element having a fifth sense terminal for transmitting a fifth sense signal according to
   It flows in the 6th switch part connected in series with the low potential input part and the 3rd connection point between the low potential input part and the 3rd connection point, and flows into the 6th switch part A sixth semiconductor switch element having a sixth sense terminal for transmitting a sixth sense signal according to the current;
   A third output unit connected to the third connection point for outputting the third output current;
   Have
   The control circuit
   Failure of the first current sensor based on the comparison result of the first sense signal and the first current detection signal, and the comparison result of the second sense signal and the first current detection signal To determine
   Failure of the second current sensor based on the comparison result of the third sense signal and the second current detection signal and the comparison result of the fourth sense signal and the second current detection signal A power converter, which is configured to determine
10. The control circuit
    A value of the third output current is obtained as a current operation value from the first current detection signal and the second current detection signal,
    An output of the first power conversion circuit, an output of the second power conversion circuit, and the third power conversion based on the first current detection signal, the second current detection signal, and the current operation value Control the output of the circuit,
    The power converter according to claim 9, configured as follows.
11. A high potential input unit to which a high DC potential is applied;
    A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
    A first power conversion circuit connected to the high potential input unit and the low potential input unit to output a first output current;
    A second power conversion circuit connected to the high potential input unit and the low potential input unit to output a second output current;
    A third power conversion circuit connected to the high potential input unit and the low potential input unit to output a third output current;
    A control circuit that controls the first power conversion circuit, the second power conversion circuit, and the third power conversion circuit;
    Equipped with
    The first power conversion circuit is
    A first switch connected in series with the high potential input and the first connection between the high potential input and the first connection, and a current flowing through the first switch A first semiconductor switch element having a first sense terminal for emitting a first sense signal according to
    A second switch connected in series with the low potential input and the first connection between the low potential input and the first connection, and a current flowing through the second switch A second semiconductor switch element having a second sense terminal for transmitting a second sense signal according to the current;
    A first output connected to the first connection point for outputting the first output current;
    A first current sensor for emitting a first current detection signal according to the first output current;
    Have
    The second power conversion circuit is
    A third switch connected in series with the high potential input and the second connection between the high potential input and the second connection, and a current flowing through the third switch A third semiconductor switch element having a third sense terminal for transmitting a third sense signal according to
    It flows into the 4th switch part connected in series with the low potential input part and the 2nd connection point between the low potential input part and the 2nd connection point, and flows into the 4th switch part A fourth semiconductor switch element having a fourth sense terminal for transmitting a fourth sense signal according to the current;
    A second output connected to the second connection point for outputting the second output current;
    The third power conversion circuit is
    A fifth semiconductor switch element having a fifth switch portion connected in series to the high potential input portion and the third connection point between the high potential input portion and the third connection point;
    A sixth semiconductor switch element having a sixth switch portion connected in series to the low potential input portion and the third connection point between the low potential input portion and the third connection point;
    A third output unit connected to the third connection point for outputting the third output current;
    A second current sensor that transmits a second current detection signal according to the third output current;
    Have
    The control circuit
    Failure of the first current sensor based on the comparison result of the first sense signal and the first current detection signal, and the comparison result of the second sense signal and the first current detection signal To determine
    A sense operation value is obtained from the first sense signal, the second sense signal, the third sense signal, and the fourth sense signal,
    Determining a failure of the second current sensor based on a comparison result of the sense calculation value and the second current detection signal;
    A power converter that is configured to:
12. A high potential input unit to which a high DC potential is applied;
    A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
    A first power conversion circuit connected to the high potential input unit and the low potential input unit to output a first output current;
    A second power conversion circuit connected to the high potential input unit and the low potential input unit to output a second output current;
    A third power conversion circuit connected to the high potential input unit and the low potential input unit to output a third output current;
    A control circuit that controls the first power conversion circuit, the second power conversion circuit, and the third power conversion circuit;
    Equipped with
    The first power conversion circuit is
    A first switch connected in series with the high potential input and the first connection between the high potential input and the first connection, and a current flowing through the first switch A first semiconductor switch element having a first sense terminal for emitting a first sense signal according to
    A second switch connected in series with the low potential input and the first connection between the low potential input and the first connection, and a current flowing through the second switch A second semiconductor switch element having a second sense terminal for transmitting a second sense signal according to the current;
    A first output connected to the first connection point for outputting the first output current;
    A first current sensor for emitting a first current detection signal according to the first output current;
    Have
    The second power conversion circuit is
    A third switch connected in series with the high potential input and the second connection between the high potential input and the second connection, and a current flowing through the third switch A third semiconductor switch element having a third sense terminal for transmitting a third sense signal according to
    It flows into the 4th switch part connected in series with the low potential input part and the 2nd connection point between the low potential input part and the 2nd connection point, and flows into the 4th switch part A fourth semiconductor switch element having a fourth sense terminal for transmitting a fourth sense signal according to the current;
    A second output connected to the second connection point for outputting the second output current;
    The third power conversion circuit is
    A fifth semiconductor switch element having a fifth switch portion connected in series to the high potential input portion and the third connection point between the high potential input portion and the third connection point;
    A sixth semiconductor switch element having a sixth switch portion connected in series to the low potential input portion and the third connection point between the low potential input portion and the third connection point;
    A third output unit connected to the third connection point for outputting the third output current;
    A second current sensor that transmits a second current detection signal according to the third output current;
    Have
    The control circuit
    Failure of the first current sensor based on the comparison result of the first sense signal and the first current detection signal, and the comparison result of the second sense signal and the first current detection signal To determine
    The value of the second output current is obtained as a current operation value from the first current detection signal and the second current detection signal,
    Determining a failure of the second current sensor based on a comparison result of the third sense signal and the fourth current operation value, and a comparison result of the fourth sense signal and the second current value;
    A power converter that is configured to:
13. A high potential input unit to which a high DC potential is applied;
    A low potential input unit to which a low direct current potential lower than the high direct current potential is applied;
    A first power conversion circuit connected to the high potential input unit and the low potential input unit to output a first output current;
    A second power conversion circuit connected to the high potential input unit and the low potential input unit to output a second output current;
    A third power conversion circuit connected to the high potential input unit and the low potential input unit to output a third output current;
    A control circuit that controls the first power conversion circuit, the second power conversion circuit, and the third power conversion circuit;
    Equipped with
    The first power conversion circuit is
    A first switch connected in series with the high potential input and the first connection between the high potential input and the first connection, and a current flowing through the first switch A first semiconductor switch element having a first sense terminal for emitting a first sense signal according to
    A second switch connected in series with the low potential input and the first connection between the low potential input and the first connection, and a current flowing through the second switch A second semiconductor switch element having a second sense terminal for transmitting a second sense signal according to the current;
    A first output connected to the first connection point for outputting the first output current;
    Have
    The second power conversion circuit is
    A third semiconductor switch element having a third switch portion connected in series to the high potential input portion and the second connection point between the high potential input portion and the second connection point;
    A fourth semiconductor switch element having a fourth switch portion connected in series to the low potential input portion and the second connection point between the low potential input portion and the second connection point;
    A second output connected to the second connection point for outputting the second output current;
    A first current sensor transmitting a first current detection signal according to the second output current;
    The third power conversion circuit is
    A fifth semiconductor switch element having a fifth switch portion connected in series to the high potential input portion and the third connection point between the high potential input portion and the third connection point;
    A sixth semiconductor switch element having a sixth switch portion connected in series to the low potential input portion and the third connection point between the low potential input portion and the third connection point;
    A third output unit connected to the third connection point for outputting the third output current;
    A second current sensor that transmits a second current detection signal according to the third output current;
    Have
    The control circuit
    The value of the first output current is obtained as a current operation value from the first current detection signal and the second current detection signal,
    The first current sensor and the second current based on the comparison result of the first sense signal and the first current operation value and the comparison result of the second sense signal and the first current value Determine sensor failure,
    A power converter that is configured to:

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