Disconnection detection device and vehicle

Abstract

To detect a disconnection of coils of three phases constituting a motor in simple configuration.SOLUTION: A disconnection detection device 200 comprises: a motor 14 in which a delta connection is performed on a motor coil 14U, a motor coil 14V and a motor coil 14W of three phases; a battery 11 which supplies drive power of the motor 14; a motor driver 13 by which DC power inputted from the battery 11 is converted into AC power and the AC power is supplied to the phases of the motor 14; and a disconnection detection section 313 which detects a disconnection DS of the motor coil 14U, the motor coil 14V and the motor coil 14W. The motor driver 13 includes a higher harmonic detection circuit 15 which detects a higher harmonic of a rotation frequency FM of the motor 14 and based on a detection result of the higher harmonic detection circuit 15, the disconnection detection section 313 detects the disconnection DS of the motor coil 14U, the motor coil 14V and the motor coil 14W.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a wire break detection device and a vehicle. [Background technology]

[0002] 2. Description of the Related Art Conventionally, techniques for detecting breaks in motor windings are known. For example, Patent Document 1 describes an open-phase detection system that includes a star-connected three-phase static induction machine, a current detector, an extraction unit, and a judgment unit. The three-phase static induction machine has a primary circuit in which an excitation current flows through the wiring of each phase. The current detector detects the excitation current of each phase of the primary circuit. The extraction unit extracts harmonics from the excitation current detected by the current detector. The judgment unit judges whether the wiring of the primary circuit that detected the excitation current is open or connected, depending on whether harmonics have been extracted by the extraction unit. Furthermore, in recent years, efforts to realize a low-carbon or carbon-free society have become more active, and research and development into electrification technologies is being conducted in order to reduce CO2 emissions and improve energy efficiency in vehicles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-028501 Summary of the Invention [Problem to be solved by the invention]

[0004] However, for example, when the windings of a three-phase motor are star-connected, current can continue to flow even if a portion of the winding is broken, making it difficult to detect the break. Furthermore, in the field of electrification technology, it is an issue to detect breaks in the windings of a three-phase motor using a simple configuration. The present invention aims to solve the above-mentioned problems by detecting breaks in the windings of a three-phase motor with a simple configuration, which will ultimately contribute to improving energy efficiency. [Means for solving the problem]

[0005] One aspect of the present invention is a motor having three-phase windings in a delta connection, a battery that supplies driving power to the motor, and a power converter that converts DC power input from the battery into AC power and supplies AC power to each phase of the motor. The winding constituting and a disconnection detection unit that detects a disconnection in the winding, wherein the drive circuit has a harmonic detection circuit that detects harmonics of the rotation frequency of the motor, and the disconnection detection unit detects a disconnection in the winding based on the detection result of the harmonic detection circuit. [Effects of the Invention]

[0006] According to the present invention, a break in the windings of a three-phase motor can be detected with a simple configuration. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a vehicle drive control device equipped with a wire breakage detection device. [Figure 2] FIG. 10 is a diagram showing an example of a current flowing through a wire breakage detection device when a wire breakage occurs. [Figure 3] FIG. 1 is a diagram showing an example of the configuration of a disconnection detection device. [Figure 4] FIG. 10 is a diagram showing an example of frequency characteristics of a band-pass filter. [Figure 5] 10 is a flowchart showing an example of processing by a control device. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] [1. Configuration of vehicle drive control device] First, the configuration of the vehicle drive control device 100 will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the vehicle drive control device 100. The vehicle drive control device 100 is mounted on a vehicle VC and controls the driving of the vehicle VC. The vehicle drive control device 100 includes a wire break detection device 200. The disconnection detection device 200 will be further described with reference to FIG.

[0010] As shown in FIG. 1, the vehicle drive control device 100 includes a motor drive circuit 1, a driver drive circuit 2, and a control device 3. The motor drive circuit 1 is a circuit for driving a motor 14, and includes a battery 11, a capacitor 12, and a motor driver 13.

[0011] The battery 11 supplies power to the motor 14 via the motor driver 13 .

[0012] The capacitor 12 is disposed between the positive terminal 13P and the negative terminal 13N of the motor driver 13. The capacitor 12 is connected between the positive terminal 13P and the negative terminal 13N of the motor driver 13. Capacitor 12 suppresses changes in the output voltage of battery 11 that accompany the opening and closing of the switching elements of motor driver 13A, as well as suppresses surge voltages and surge currents that accompany the opening and closing of the switching elements. Capacitor 12 is a so-called "smoothing capacitor." The motor driver 13 corresponds to an example of a "drive circuit."

[0013] The motor driver 13 is configured with MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) 13H1, 13H2, 13H3, 13L1, 13L2, and 13L3. Each of these six MOSFETs is turned on and off based on an instruction from the driver driving circuit 2. The motor driver 13 has a positive terminal 13P and a negative terminal 13N. The positive terminal 13P is connected to the positive side of the battery 11. The negative terminal 13N is connected to the negative side of the battery 11. The MOSFET 13H1, the MOSFET 13H2, and the MOSFET 13H3 are connected to the positive terminal 13P. The MOSFET 13L1, the MOSFET 13L2, and the MOSFET 13L3 are connected to the negative terminal 13N. The motor driver 13 corresponds to an example of a "drive circuit."

[0014] The motor 14 is, for example, a three-phase synchronous motor using a permanent magnet. As shown in Fig. 1, the motor 14 includes a motor coil 14U, a motor coil 14V, and a motor coil 14W. The motor coils 14U, 14V, and 14W are delta-connected. The motor coil 14U, the motor coil 14V, and the motor coil 14W correspond to an example of a "winding." The motor 14 drives the vehicle VC with power supplied from the battery 11 via the motor driver 13. The vehicle VC is, for example, a motorbike (motorcycle).

[0015] In this embodiment, the vehicle VC is a motorbike (two-wheeled motor vehicle), i.e., a so-called "saddle-ride type vehicle," but is not limited to this. The vehicle VC may be, for example, a four-wheeled passenger car or a four-wheeled large vehicle. The vehicle VC may also be, for example, a work vehicle such as a tractor.

[0016] An angular velocity sensor 16 is provided on the motor 14. The angular velocity sensor 16 is configured with a so-called resolver, a Hall element, or the like, and detects the rotational angular velocity ω of the motor 14. The angular velocity sensor 16 outputs the detected rotational angular velocity ω to the control device 3.

[0017] The control device 3 controls the driver driving circuit 2 . The driver drive circuit 2 controls the motor driver 13 in accordance with instructions from the control device 3. That is, the driver drive circuit 2 controls the on / off of each of the six MOSFETs that make up the motor driver 13 in accordance with instructions from the control device 3.

[0018] One terminal of motor coil 14U (the upper right terminal in FIG. 1) is connected to plus terminal 13P via MOSFET 13H1, and the other terminal of motor coil 14U is connected to minus terminal 13N via MOSFET 13L2. 1, when a current is to flow through the motor coil 14U, the driver driving circuit 2 turns on the MOSFET 13H1 and the MOSFET 13L2, and turns off the MOSFET 13H2, the MOSFET 13H3, the MOSFET 13L1, and the MOSFET 13L3.

[0019] One terminal of motor coil 14V (the upper left terminal in FIG. 1) is connected to plus terminal 13P via MOSFET 13H1, and the other terminal of motor coil 14V is connected to minus terminal 13N via MOSFET 13L3. Therefore, when a current is to flow through the motor coil 14V, the driver driving circuit 2 turns on the MOSFET 13H1 and the MOSFET 13L3, and turns off the MOSFET 13H2, the MOSFET 13H3, the MOSFET 13L1, and the MOSFET 13L2.

[0020] One terminal of motor coil 14W (the terminal on the left side in FIG. 1) is connected to plus terminal 13P via MOSFET 13H2, and the other terminal of motor coil 14V is connected to minus terminal 13N via MOSFET 13L3. Therefore, when a current is to flow through the motor coil 14W, the driver driving circuit 2 turns on the MOSFET 13H2 and the MOSFET 13L3, and turns off the MOSFET 13H1, the MOSFET 13H3, the MOSFET 13L1, and the MOSFET 13L2.

[0021] As described above, the DC voltage of battery 11 is applied to each of motor coils 14U, 14V, and 14W by controlling the on / off of each of the six MOSFETs that make up motor driver 13. Note that a square wave voltage is applied to each of motor coils 14U, 14V, and 14W. The square wave voltage is expressed as an infinite series sum of sine waves containing odd-order frequencies of the fundamental wave, the rotational frequency FM of the motor 14. Therefore, the currents flowing through the motor coils 14U, 14V, and 14W each contain a third harmonic.

[0022] Next, the disconnection detection device 200 will be described with reference to FIG. The disconnection detection device 200 includes a harmonic detection circuit 15 and a disconnection detection unit 313 . The harmonic detection circuit 15 includes a band-pass filter 151 , a band-pass filter 152 , a band-pass filter 153 , a shunt resistor 154 , and a voltage sensor 155 . The harmonic detection circuit 15 constitutes a "part of the disconnection detection device."

[0023] The shunt resistor 154 and the voltage sensor 155 are connected in parallel to each other and are arranged between the negative terminals of the bandpass filters 151, 152, and 153 and the negative terminal 13N. The voltage sensor 155 detects a voltage DT generated in the shunt resistor 154 due to a current flowing through the shunt resistor 154 via the band-pass filter 151, the band-pass filter 152, or the band-pass filter 153. The voltage sensor 155 outputs the detected voltage DT to the control device 3.

[0024] In this embodiment, a case will be described in which the voltage sensor 155 outputs the detected voltage DT to the control device 3, but the embodiment is not limited to this. For example, a current sensor may be provided instead of the voltage sensor 155, and the current sensor may output a current value calculated from the voltage DT and the resistance value of the shunt resistor 154 to the control device 3. In this case, the control device 3 detects a break in the coil of the motor 14 based on the input current value.

[0025] Each of the band-pass filter 151, the band-pass filter 152, and the band-pass filter 153 is configured by a digital filter. The pass band BW of each of the band-pass filter 151, the band-pass filter 152, and the band-pass filter 153 is set by the control device 3 so as to include a frequency three times the rotation frequency FM of the motor 14.

[0026] The bandpass filter 151 is disposed between the positive terminal of the MOSFET 13L1 and the positive terminal of the shunt resistor 154. Of the current flowing through the MOSFET 13L1, a current having a frequency included in the pass band BW of the bandpass filter 151 flows through the shunt resistor 154. The bandpass filter 152 is disposed between the positive terminal of the MOSFET 13L2 and the positive terminal of the shunt resistor 154. Of the current flowing through the MOSFET 13L2, a current having a frequency included in the pass band BW of the bandpass filter 152 flows through the shunt resistor 154. The bandpass filter 153 is disposed between the positive terminal of the MOSFET 13L3 and the positive terminal of the shunt resistor 154. Of the current flowing through the MOSFET 13L3, a current having a frequency included in the pass band BW of the bandpass filter 153 flows through the shunt resistor 154.

[0027] That is, the shunt resistor 154 receives a current having a frequency included in the pass band BW of the band pass filters 151 to 153, out of the currents flowing through the MOSFET 13L1, MOSFET 13L2, or MOSFET 13L3. The passband BW is further explained with reference to FIG. The control device 3 will be further described with reference to FIGS.

[0028] [2. Principle of detecting a wire break using a wire break detector] As shown in FIG. 1, when motor coil 14U, motor coil 14V, and motor coil 14W are in a balanced state, the current values ​​(iu, iv, iw) of the currents flowing through motor coil 14U, motor coil 14V, and motor coil 14W, respectively, at a frequency three times the rotational frequency FM of motor 14 are expressed by the following equations (1), (2), and (3). Current value iu indicates the current value of the current flowing through motor coil 14U at a frequency three times the rotational frequency FM of motor 14. Current value iv indicates the current value of the current flowing through motor coil 14V at a frequency three times the rotational frequency FM of motor 14. Current value iw indicates the current value of the current flowing through motor coil 14W at a frequency three times the rotational frequency FM of motor 14. iu=I×sin3ωt (1) iv=I×sin(3ωt-2π)=I×sin3ωt (2) iw=I×sin(3ωt-4π)=I×sin3ωt (3) Here, the coefficient I indicates the amplitude of the current, the coefficient ω indicates the angular frequency of the current, and the coefficient t indicates time.

[0029] The angular frequency ω is calculated using the rotational frequency FM as ω = (2π × FM). The magnitude of the current amplitude I is determined based on the voltage applied to both ends of the coil of each phase and the impedance. If the applied voltage is the same for each phase and there is no break in motor coil 14U, motor coil 14V, and motor coil 14W, the impedance of the coil of each phase is the same, so the amplitude of the current flowing through the coil of each phase is the same. That is, among the currents flowing through motor coil 14U, motor coil 14V, and motor coil 14W, the current values ​​at a frequency three times the rotational frequency FM of motor 14 match each other. Note that, among the currents flowing through motor coil 14U, motor coil 14V, and motor coil 14W, the currents at a frequency that is an integer multiple of "3" the rotational frequency FM of motor 14 also match each other.

[0030] As a result, when motor coils 14U, 14V, and 14W are in a balanced state, a current having a frequency three times the rotational frequency FM of motor 14 circulates within the delta connection. The direction of the current circulating within the delta connection is the same as the direction of the current flowing from inverter 13. For example, in the example of FIG. 1, the current flowing from inverter 13 to coil 14U flows from between coils 14U and 14V to between coils 14U and 14W, so that the current having a frequency three times the rotational frequency FM of motor 14 circulates counterclockwise within the delta connection in FIG. 1. Furthermore, according to Kirchhoff's law, the current having a frequency three times the rotational frequency FM of motor 14 does not flow outside the delta connection formed by motor coils 14U, 14V, and 14W.

[0031] Next, a current that flows through the disconnection detection device 200 when a disconnection DS occurs will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of a current that flows through the disconnection detection device 200 when a disconnection DS occurs. Fig. 2 describes a case where a disconnection DS occurs in a part of the motor coil 14U.

[0032] If a break DS occurs in a part of the motor coil 14U, the impedance of the motor coil 14U increases, and therefore the current value of the current flowing through the motor coil 14U at a frequency three times the rotational frequency FM of the motor 14 becomes smaller than the current value of the current flowing through the motor coil 14V at a frequency three times the rotational frequency FM of the motor 14, and the current value of the current flowing through the motor coil 14W at a frequency three times the rotational frequency FM of the motor 14.

[0033] As a result, a current having a frequency three times the rotation frequency FM of the motor 14 flows out from the coupling terminal between the motor coils 14U and 14W, as shown by the dashed dotted line in Figure 2. The current then flows into the battery 11 via the MOSFET 13L2, or the band-pass filter 152 and the shunt resistor 154.

[0034] The passband BW of the bandpass filter 152 is set by the control device 3 so as to include a frequency three times the rotation frequency FM of the motor 14, and therefore a current having a frequency three times the rotation frequency FM of the motor 14 passes through the bandpass filter 152. The current having a frequency three times the rotation frequency FM of the motor 14 generates a voltage having a frequency three times the rotation frequency FM of the motor 14 across the shunt resistor 154. The voltage sensor 155 detects a voltage DT generated across the shunt resistor 154. The voltage sensor 155 outputs the detected voltage DT to the control device 3.

[0035] The disconnection detection unit 3131 detects a disconnection of the motor coil 14U based on the voltage DT detected by the voltage sensor 155.

[0036] [3. Configuration of the disconnection detection device] Next, the configuration of the disconnection detection device 200 will be described with reference to Fig. 3. Fig. 3 is a diagram showing an example of the configuration of the disconnection detection device 200. As shown in FIG. 2, the disconnection detection device 200 includes a control device 3, a notification unit 4, an angular velocity sensor 16, a band-pass filter 151, a band-pass filter 152, a band-pass filter 153, and a voltage sensor 155.

[0037] The control device 3 is configured by, for example, an ECU (Electronic Control Unit), and includes a processor 31 such as a CPU (Central Processing Unit), and a memory 32 such as a ROM (Read Only Memory).

[0038] The memory 32 is a storage device that non-volatilely stores programs and data executed by the processor 31. The memory 32 is configured by a magnetic storage device, a semiconductor storage element such as a flash ROM, or other types of non-volatile storage device. The memory 32 may also include a RAM (Random Access Memory) that configures the work area of ​​the processor 31. The memory 32 stores data processed by the control device 3 and a control program 321 executed by the processor 31.

[0039] The processor 31 may be configured as a single processor, or may be configured such that multiple processors function as the processor 31. The processor 31 executes a control program 321 to detect disconnections in the motor coil 14U, the motor coil 14V, and the motor coil 14W. The control device 3 includes a frequency setting unit 311, a voltage acquisition unit 312, and a disconnection detection unit 313. Specifically, the processor 31 of the control device 3 executes a control program 321, thereby functioning as the frequency setting unit 311, the voltage acquisition unit 312, and the disconnection detection unit 313. The control device 3 constitutes "a part of the disconnection detection device."

[0040] The frequency setting unit 311 acquires the rotational angular velocity ω of the motor 14 from the angular velocity sensor 16. Then, the frequency setting unit 311 calculates the rotational speed N (times / second) of the motor 14 using the following equation (4). N=ω / 2π (4) Next, the frequency setting unit 311 calculates the rotation frequency FM (Hz) of the motor 14 using the following equation (5). FM=N (5) Furthermore, the frequency F3 that is three times the rotation frequency FM of the motor 14, that is, the frequency F3 of the third harmonic, is calculated using the following equation (6). F3=3×FM (6) By substituting equations (4) and (5) into equation (6), the following equation (7) is obtained. F3=3×ω / 2π (7)

[0041] The frequency setting unit 311 calculates a frequency F3 that is three times the rotation frequency FM of the motor 14 using equation (7), and sets the frequency F3 as the center frequency FC for each of the bandpass filters 151, 152, and 153. Bandpass filter 151, bandpass filter 152, and bandpass filter 153 will be further described with reference to FIG.

[0042] The voltage acquisition unit 312 acquires a voltage DT from the voltage sensor 155. The voltage DT indicates a voltage drop across the shunt resistor 154 due to a current that has passed through the band-pass filter 151, the band-pass filter 152, or the band-pass filter 153. The frequency of the current that passes through the band-pass filter 151, the band-pass filter 152, or the band-pass filter 153 is included in the pass band BW of each of the band-pass filters 151, 152, and 153. The pass band BW includes a frequency F3 that is three times the rotation frequency FM of the motor 14.

[0043] As explained with reference to Fig. 1, when no open circuit DS occurs, voltage DT is approximately "0." In contrast, as explained with reference to Fig. 2, when an open circuit DS occurs, a current having a frequency three times the rotational frequency FM of motor 14 flows out from the coupling terminal between motor coil 14U and motor coil 14W, as shown by the dashed-dotted line in Fig. 2. Voltage DT is the product of the current value of the flowed-out current and the resistance value of shunt resistor 154. Furthermore, the greater the number of broken coils in the motor coil 14U due to the broken wires DS, the greater the voltage DT.

[0044] The disconnection detection unit 313 detects a disconnection DS in the motor coil 14U, the motor coil 14V, and the motor coil 14W. The disconnection detection unit 313 detects that a disconnection DS has occurred when, for example, the voltage DT acquired by the voltage acquisition unit 312 is equal to or greater than a preset threshold value TH. When the disconnection detection unit 313 detects a disconnection DS in the motor coil 14U, the motor coil 14V, and the motor coil 14W, it outputs instruction information AL to the notification unit 4 to instruct the notification unit 4 to notify a user, for example, the driver of the vehicle VC.

[0045] The notification unit 4 includes, for example, a display such as an LCD (Liquid Crystal Display). When the notification unit 4 receives instruction information AL from the disconnection detection unit 313, it displays an image indicating that a disconnection DS has occurred on the display. For example, the notification unit 4 displays a text image stating, "A disconnection has occurred in the motor winding. Please slow down and stop."

[0046] The notification unit 4 may also include, for example, a speaker. In this case, when the notification unit 4 receives instruction information AL from the disconnection detection unit 313, the notification unit 4 displays a sound from the speaker indicating that a disconnection DS has occurred.

[0047] Next, the frequency characteristics of band-pass filter 151, band-pass filter 152, and band-pass filter 153 will be described with reference to Fig. 4. Fig. 4 is a diagram showing an example of the frequency characteristics of band-pass filter 151, band-pass filter 152, and band-pass filter 153. The vertical axis in FIG. 4 represents the attenuation characteristics of the bandpass filters 151 to 153, that is, (output current value / input current value), and the horizontal axis in FIG. 4 represents the frequency F of the input current.

[0048] 4, the pass band BW of the band pass filters 151 to 153 is set to a frequency between a first frequency F1 and a second frequency F2. The center frequency FC of the pass band BW is set by the frequency setting unit 311 to a frequency F3 that is three times the rotation frequency FM of the motor 14, as shown in the above equation (4).

[0049] The first frequency F1 and the second frequency F2 are defined by the following equations (8) and (9). F1=FC-ΔF (8) F2=FC+ΔF (9) The difference frequency ΔF is half the passband BW. The differential frequency ΔF may be a constant value, or may be increased as the center frequency FC increases.

[0050] [4. Processing of control device] Next, the processing of the control device 3 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing an example of the processing of the control device 3. First, in step S101 , the frequency setting unit 311 acquires the rotational angular velocity ω of the motor 14 from the angular velocity sensor 16 . Next, in step S103, the frequency setting unit 311 sets a center frequency FC for each of the band-pass filter 151, the band-pass filter 152, and the band-pass filter 153. The center frequency FC is a frequency F3 that is three times the rotation frequency FM of the motor 14.

[0051] Next, in step S105, the voltage acquisition unit 312 acquires the voltage DT from the voltage sensor 155. The voltage DT indicates a voltage drop across the shunt resistor 154 due to a current that has passed through the bandpass filter 151, the bandpass filter 152, or the bandpass filter 153. Next, in step S107, the disconnection detection unit 313 determines whether the voltage DT acquired by the voltage acquisition unit 312 is equal to or greater than a preset threshold value TH.

[0052] If the disconnection detection unit 313 determines that the voltage DT is not equal to or greater than the threshold value TH (step S107; NO), the process returns to step S101. If the disconnection detection unit 313 determines that the voltage DT is equal to or greater than the threshold value TH (step S107; YES), the process proceeds to step S109. Then, in step S109, the notification unit 4 notifies that the disconnections DS of the motor coils 14U, 14V, and 14W have been detected, and then the process ends.

[0053] [5. Composition and Effects] As described above, the disconnection detection device 200 of this embodiment includes a motor 14 in which three-phase motor coils 14U, 14V, and 14W are delta-connected, a battery 11 that supplies driving power to the motor 14, a motor driver 13 that converts DC power input from the battery 11 into AC power and supplies the AC power to each phase of the motor 14, and a disconnection detection unit 313 that detects disconnections DS in the motor coils 14U, 14V, and 14W, the motor driver 13 having a harmonic detection circuit 15 that detects harmonics of the rotation frequency FM of the motor 14, and the disconnection detection unit 313 detects disconnections DS in the motor coils 14U, 14V, and 14W based on the detection results of the harmonic detection circuit 15.

[0054] According to this configuration, harmonic detection circuit 15 detects harmonics of rotation frequency FM of motor 14, and disconnection detection unit 313 detects disconnections DS of motor coils 14U, 14V, and 14W based on the detection results of harmonic detection circuit 15. Therefore, disconnections DS of motor coils 14U, 14V, and 14W can be detected with a simple configuration.

[0055] In addition, in the disconnection detection device 200, the harmonic detection circuit 15 has a band-pass filter 151, a band-pass filter 152, and a band-pass filter 153, and a frequency setting unit 311 that sets the pass band BW of the band-pass filters 151 to 153 to include a frequency three times the rotation frequency FM of the motor 14.

[0056] According to this configuration, the pass band BW of the band pass filters 151 to 153 is set to include a frequency three times the rotation frequency FM of the motor 14. Therefore, it is possible to accurately detect breaks DS in the motor coils 14U, 14V, and 14W with a simple configuration.

[0057] In the disconnection detection device 200, the harmonic detection circuit 15 detects harmonics of the rotation frequency FM of the motor 14 from the AC power supplied to each phase of the motor 14.

[0058] According to this configuration, the breaks DS in the motor coils 14U, 14V, and 14W can be detected with a simple configuration.

[0059] The vehicle VC of this embodiment comprises a motor 14 in which three-phase motor coils 14U, 14V, and 14W are delta-connected, a battery 11 that supplies driving power to the motor 14, a motor driver 13 that converts DC power input from the battery 11 into AC power and supplies the AC power to each phase of the motor 14, and a disconnection detection unit 313 that detects disconnections DS in the motor coils 14U, 14V, and 14W, the motor driver 13 having a harmonic detection circuit 15 that detects harmonics of the rotational frequency FM of the motor 14, and the disconnection detection unit 313 detects disconnections DS in the motor coils 14U, 14V, and 14W based on the detection results of the harmonic detection circuit 15.

[0060] This configuration provides the same effects as those of the disconnection detection device 200 according to this embodiment.

[0061] 6. Other Embodiments The present invention is not limited to the configurations of the above-described embodiments, and can be implemented in various forms without departing from the spirit of the invention.

[0062] For example, in the above embodiment, the "switching element" is a MOSFET, but is not limited to this. The "switching element" may be, for example, a power transistor or an IGBT (Insulated Gate Bipolar Transistor).

[0063] Furthermore, in the above embodiment, the harmonic detection circuit 15 detects the third harmonic of the rotation frequency FM of the motor 14, but this is not limiting. The harmonic detection circuit 15 may simply detect the harmonics of the rotation frequency FM of the motor 14. For example, the harmonic detection circuit 15 may detect the sixth harmonic of the rotation frequency FM of the motor 14. Note that, as in the above embodiment, it is preferable that the harmonic detection circuit 15 detects the third harmonic of the rotation frequency FM of the motor 14.

[0064] At least some of the functional blocks shown in Figure 3 may be realized by hardware, or may be realized by a combination of hardware and software, and are not limited to a configuration in which independent hardware resources are arranged as shown in the figure. The control program 321 executed by the processor 31 of the control device 3 is stored in the memory 32, but the control program 321 may also be stored in an external HDD or the like.

[0065] The processing units in the flowchart shown in FIG. 5 are divided according to the main processing content to facilitate understanding of the processing of the control device 3 of the disconnection detection device 200. The embodiment is not limited by the way in which the processing units are divided or the names of the processing units shown in the flowchart of FIG. 5. The processing of the control device 3 can be divided into more processing units depending on the processing content, or one processing unit can be divided so that it includes more processes. The processing order of the above flowchart is not limited to the example shown in the figure.

[0066] Each functional unit of the control device 3 can be realized by having the processor 31 execute a control program 321 corresponding to the control method of the control device 3. The control program 321 can be recorded on a computer-readable recording medium. The recording medium can be a magnetic or optical recording medium or a semiconductor memory device. Specifically, examples include portable or fixed recording media such as flexible disks, CD-ROMs (Compact Disk Read Only Memory), DVDs (Digital Versatile Discs), Blu-ray (registered trademark) Discs, magneto-optical disks, flash memories, and card-type recording media. The recording medium may be a non-volatile storage device such as a RAM, a ROM, or a HDD, which is an internal storage device provided in the control device 3. The control program 321 is stored in a server device or the like, and each functional unit of the control device 3 can be realized by downloading the control program 321 from the server device to the control device 3.

[0067] 7. Configurations Supported by the Above Embodiments The above embodiment supports the following configurations.

[0068] (Configuration 1) A wire break detection device comprising: a motor with three-phase windings delta-connected; a battery that supplies drive power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; and a wire break detection unit that detects wire breaks in the windings, wherein the drive circuit has a harmonic detection circuit that detects harmonics of the rotational frequency of the motor, and the wire break detection unit detects wire breaks in the windings based on the detection results of the harmonic detection circuit.

[0069] According to the wire break detection device of configuration 1, a harmonic detection circuit detects harmonics of the rotation frequency of the motor, and a wire break detection unit detects wire breaks in the windings based on the detection results of the harmonic detection circuit. Therefore, wire breaks in the three-phase windings that make up the motor can be detected with a simple configuration.

[0070] (Configuration 2) The harmonic detection circuit of the disconnection detection device described in Configuration 1 includes a bandpass filter and a frequency setting unit that sets the passband of the bandpass filter to include a frequency three times the rotational frequency of the motor.

[0071] According to the disconnection detection device of configuration 2, the pass band of the bandpass filter is set to include a frequency three times the rotation frequency of the motor, so that disconnections in the three-phase windings that make up the motor can be accurately detected with a simple configuration.

[0072] (Configuration 3) The disconnection detection device according to configuration 1 or 2, wherein the harmonic detection circuit detects harmonics of the rotation frequency of the motor with respect to the AC power supplied to each phase of the motor. According to the disconnection detection device of configuration 3, harmonics of the rotation frequency of the motor are detected for the AC power supplied to each phase of the motor, and therefore, disconnections in each of the three-phase windings that make up the motor can be detected with a simple configuration.

[0073] (Configuration 4) A vehicle comprising: a motor having three-phase windings delta-connected; a battery that supplies drive power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; and an open circuit detection unit that detects open circuits in the windings, wherein the drive circuit has a harmonic detection circuit that detects harmonics of the rotational frequency of the motor, and the open circuit detection unit detects open circuits in the windings based on the detection results of the harmonic detection circuit.

[0074] According to the vehicle of the fourth aspect, the same effects as those of the disconnection detection device of the first aspect are achieved. [Explanation of symbols]

[0075] 100 Vehicle drive control device 200 Disconnection detection device 1 Motor drive circuit 11 Battery 12 Capacitors 13 Motor driver (drive circuit) 13P positive terminal 13N negative terminal 13H1, 13H2, 13H3, 13L1, 13L2, 13L3 MOSFET 14 Motor 14U, 14V, 14W motor coil (winding) 15 Harmonic detection circuit (part of the disconnection detection device) 151, 152, 153 Bandpass filters 154 Shunt Resistor 155 Voltage Sensor 2 Driver drive circuit 3. Control device (part of the disconnection detection device) 31 processors 311 Frequency setting unit 312 Voltage acquisition unit 313 Disconnection detection unit 32 Memory 321 Control Program BW Passband FM rotation frequency FC center frequency VC vehicle

Claims

1. A motor with three-phase windings delta-connected; a battery that supplies driving power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to the windings that constitute each phase of the motor; a breakage detection unit that detects breakage of the winding; Equipped with the drive circuit has a harmonic detection circuit that detects harmonics of the rotation frequency of the motor, the disconnection detection unit detects a disconnection of the winding based on a detection result of the harmonic detection circuit. Disconnection detection device.

2. The harmonic detection circuit includes a bandpass filter and a frequency setting unit that sets the pass band of the band pass filter to include a frequency that is three times the rotation frequency of the motor; having The wire break detection device according to claim 1 .

3. the harmonic detection circuit detects harmonics of the rotation frequency of the motor with respect to the AC power supplied to the windings constituting each phase of the motor.

3. The wire breakage detection device according to claim 1 or 2.

4. A motor with three-phase windings delta-connected; a battery that supplies driving power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to the windings that constitute each phase of the motor; a breakage detection unit that detects breakage of the winding; Equipped with the drive circuit has a harmonic detection circuit that detects harmonics of the rotation frequency of the motor, the disconnection detection unit detects a disconnection of the winding based on a detection result of the harmonic detection circuit. vehicle.

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