JP2014050170A - Drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform self-diagnosis of a leakage detector more correctly, while suppressing the operating noise of an inverter from increasing during self-diagnosis.SOLUTION: During self-diagnosis of a leakage detector, a spread frequency fspr1 multiplied by a coefficient k, set by using a random sequence, is added to a basic carrier frequency f1 thus setting a carrier frequency f1* for execution of a first inverter (step S110). A carrier frequency f2* for execution of a second inverter is then set by subtracting a predetermined value α from the carrier frequency f1* for execution thus set (step S120). This process is executed periodically. Since the carrier frequencies f1*, f2* for execution of the first and second inverters change periodically so that the difference between them has a predetermined value α, self-diagnosis of the leakage detector can be performed more correctly, while suppressing the operating noise of the first and second inverters from increasing during self-diagnosis.

Description

  The present invention relates to a drive device.

  Conventionally, as a driving device, two motors, two inverters that respectively drive the two motors, a battery that exchanges power with the two motors via the two inverters, and a negative terminal of the battery In the vehicle state where the generated sound of the vehicle is low (the state where the operation sound due to the carrier signal of the inverter is easily detected by the user), the leakage detection device detects the leakage (the circuit insulation resistance is low). 2), the two inverters are controlled using carrier frequency control for changing the carrier frequency, and when the generated sound of the vehicle is not low, the carrier frequency is fixed to 2 One that controls two inverters and performs leakage detection by a leakage detection device has been proposed (for example, See Patent Document 1). In this device, by such processing, when the vehicle generated sound is low, the inverter operating sound is reduced and erroneous detection of leakage is prevented. When the vehicle generated sound is not low, the carrier frequency control is performed. It prevents the leakage detection from becoming abnormal due to switching noise from the inverter due to execution.

JP 2011-250558 A

  In such a drive device, when performing self-diagnosis of the leakage detection device for diagnosing whether or not leakage detection is normally performed, it is conceivable that the carrier frequency is fixed as in the above-described drive device. However, in this case, the operating noise of the inverter may become loud during the self-diagnosis of the leakage detection device. Therefore, coexistence of more appropriately performing self-diagnosis of the leakage detection device (suppressing erroneous detection) and suppressing increase of the operating noise of the inverter during the process is considered as one of the problems. Yes.

  The drive device of the present invention is mainly intended to more appropriately perform self-diagnosis of the leakage detection device and to suppress an increase in the operating noise of the inverter during that time.

  The drive device of the present invention employs the following means in order to achieve the main object described above.

The drive device of the present invention is
A first motor, a first inverter that drives the first motor, a second motor, a second inverter that drives the second motor, and the first inverter and the second inverter electrically connected A battery, a leakage detection device connected to the positive side or the negative side of the battery to detect leakage of the circuit, and the first inverter using pulse width modulation control using a first modulated wave whose frequency changes periodically Control means for controlling the second inverter by pulse width modulation control using a second modulated wave that is controlled and periodically changes in frequency, and a drive device comprising:
During the self-diagnosis of the leakage detection device, the control means periodically changes the frequency of the first modulated wave and the frequency of the second modulated wave within a range in which the difference between them is not less than a predetermined value. Is a means to
It is characterized by that.

  In the driving device of the present invention, basically, the first inverter is controlled by pulse width modulation control using the first modulated wave whose frequency changes periodically, and the second modulated wave whose frequency changes periodically. Is used to control the second inverter by pulse width modulation control. During the self-diagnosis of the leakage detection device, the frequency of the first modulated wave and the frequency of the second modulated wave are periodically changed within a range where the difference between the two becomes a predetermined value or more. If the frequency of the first modulation wave and the frequency of the second modulation wave are close to each other during self-diagnosis of the leakage detection device, the potential fluctuation at the connection position between the circuit and the leakage detection device becomes noise for the self-diagnosis of the leakage detection device. There is a possibility that this self-diagnosis cannot be performed normally. On the other hand, as described above, it is conceivable to fix the frequency of the first modulated wave and the frequency of the second modulated wave apart from each other to some extent, but in this case, the operating noise of the first inverter and the second inverter is There is a possibility of becoming large. In the drive device of the present invention, during the self-diagnosis of the leakage detection device, the frequency of the first modulated wave and the frequency of the second modulated wave are periodically changed within a range where the difference between the two becomes a predetermined value or more. As a result, the self-diagnosis of the leakage detection device can be performed more appropriately, and it is possible to suppress an increase in operating noise of the first inverter and the second inverter during the self-diagnosis.

  In such a drive device of the present invention, the control means sets one of the frequency of the first modulation wave and the frequency of the second modulation wave to a first predetermined frequency or higher during self-diagnosis of the leakage detection device. The first pattern processing is performed in which the other is periodically changed within a range, and the other is periodically changed within a second predetermined frequency that is smaller than the first predetermined frequency by the predetermined value. It may be a means for executing a second pattern process for periodically changing within the range below the second frequency and periodically changing the other within the range above the first predetermined frequency. When controlling an inverter using a modulated wave having a frequency in a high frequency region (within a range equal to or higher than the first predetermined frequency), the inverter is controlled using a modulated wave having a frequency in the low frequency region (within a range equal to or lower than the second predetermined frequency). Compared to control, the inverter temperature is likely to rise. Therefore, excessive heat generation of a specific inverter can be suppressed by executing the first pattern process and then executing the second pattern process.

  In the driving device of the present invention in which the first pattern processing is executed during the self-diagnosis of the leakage detection device and then the second pattern processing is executed thereafter, the control means executes the first pattern processing. In the meantime, when the temperature of the inverter corresponding to the one of the first inverter and the second inverter reaches a predetermined temperature or higher, means for switching from the first pattern processing to the second pattern processing. There can be. The control means may be means for switching from the first pattern process to the second pattern process when a predetermined time has elapsed since the execution of the first pattern process was started. .

  In the driving apparatus according to the present invention, the leakage detection device includes a pulse signal generating unit that generates a pulse signal by grounding one of the terminals, a first resistor having one terminal connected to the pulse signal generating unit, and one terminal. Is coupled to the other terminal of the first resistor and the other terminal is connected to the negative electrode side of the battery, and one terminal is grounded via the second resistor and the other terminal is A switching element connected to a connection point between the first resistor and the coupling capacitor, and a band-pass filter having one terminal connected to the connection point and passing a component in a frequency band corresponding to the frequency of the pulse signal Voltage detection means for detecting and outputting an output value after passing through the band-pass filter, and insulation against circuit ground using the output value from the voltage detection means Resistance of anticancer and a leakage judging means for judging whether or not reduced (a possibility there is a leakage), it can also be a thing.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as a first embodiment of the present invention. 2 is a configuration diagram showing an outline of the configuration of an electric system of a hybrid vehicle 20. FIG. It is a flowchart which shows an example of the carrier frequency setting routine for self-diagnosis execution performed by motor ECU40 of 1st Example. It is explanatory drawing which shows an example of the mode of the time change of the carrier frequency for execution f1 * and f2 * during the self-diagnosis of the electrical leakage detection apparatus 59 of 1st Example. It is a flowchart which shows an example of the carrier frequency setting routine for execution during self-diagnosis performed by motor ECU40 of 2nd Example. It is explanatory drawing which shows an example of the mode of the time change of the inverter temperature Tinv1 and self-diagnosis carrier frequency f1 *, f2 * during the self-diagnosis of the leak detection apparatus 59 of 2nd Example. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 320 of a modified example. It is a block diagram which shows the outline of a structure of the electric vehicle 420 of a modification.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with a drive device as a first embodiment of the present invention, and FIG. 2 is a configuration diagram showing an outline of an electrical system configuration of the hybrid vehicle 20. It is. As shown in FIG. 1, the hybrid vehicle 20 of the first embodiment includes an engine 22 that outputs power using gasoline or light oil as a fuel, and an engine electronic control unit (hereinafter referred to as an engine ECU) that drives and controls the engine 22. 24, a planetary gear 30 having a carrier connected to the crankshaft 26 of the engine 22 and a ring gear connected to a drive shaft 36 connected to drive wheels 38a and 38b via a differential gear 37, for example, as a synchronous generator motor Then, the motor MG1 whose rotor is connected to the sun gear of the planetary gear 30, a motor MG2 configured as, for example, a synchronous generator motor and whose rotor is connected to the drive shaft 36, and an inverter 41 for driving the motors MG1 and MG2 , 42 and inverters 41, 42 not shown. A motor electronic control unit (hereinafter referred to as a motor ECU) 40 that controls the driving of the motors MG1 and MG2 by controlling the switching of the chucking element, and a motor MG1 configured as, for example, a lithium ion secondary battery via inverters 41 and 42. , MG2 and the battery 50, a battery electronic control unit (hereinafter referred to as a battery ECU) 52 for managing the battery 50, and a connection point Cn between the negative terminal of the battery 50 and the inverters 41 and 42 (see FIG. 2) and a voltage waveform output circuit 60 for outputting a voltage waveform corresponding to the resistance value of the insulation resistance 69 with respect to the ground (vehicle body) of the circuit having the motors MG1, MG2, inverters 41, 42, and the battery 50, and the vehicle When the entire system is controlled, a hybrid electronic control unit (hereinafter referred to as HVEC) Equipped with a, a) 70 called.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The engine ECU 24 receives signals from various sensors that detect the operating state of the engine 22, for example, a water temperature sensor that detects the crank position θcr from the crank position sensor that detects the rotational position of the crankshaft 26 and the coolant temperature of the engine 22. From the cam position sensor for detecting the cooling water temperature Tw from the cylinder, the in-cylinder pressure Pin from the pressure sensor installed in the combustion chamber, the rotational position of the intake valve for intake and exhaust to the combustion chamber and the camshaft for opening and closing the exhaust valve Position θca, throttle position TP from a throttle valve position sensor that detects the position of the throttle valve, intake air amount Qa from an air flow meter attached to the intake pipe, intake air temperature Ta from a temperature sensor also attached to the intake pipe, Installed in the exhaust system The air-fuel ratio AF from the air-fuel ratio sensor and the oxygen signal O2 from the oxygen sensor attached to the exhaust system are input via the input port, and the engine ECU 24 is for driving the engine 22. Various control signals, such as the drive signal to the fuel injection valve, the drive signal to the throttle motor that adjusts the throttle valve position, the control signal to the ignition coil integrated with the igniter, and the opening / closing timing of the intake valve can be changed A control signal to the variable valve timing mechanism is output via the output port. The engine ECU 24 is in communication with the HVECU 70, controls the operation of the engine 22 by a control signal from the HVECU 70, and outputs data related to the operation state of the engine 22 to the HVECU 70 as necessary. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 and θm2 from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and not shown. The phase current applied to the motors MG1 and MG2 detected by the current sensor, the temperature of the switching elements of the inverters 41 and 42 from the temperature sensors 45 and 46 attached in the vicinity of the switching elements of the inverters 41 and 42 (hereinafter referred to as inverters) Tinv1, Tinv2, etc. (referred to as temperature) are input via the input port, and the motor ECU 40 outputs a switching control signal to a switching element (not shown) of the inverters 41, 42 via the output port. The motor ECU 40 is in communication with the HVECU 70, controls the driving of the motors MG1 and MG2 by a control signal from the HVECU 70, and outputs data related to the operating state of the motors MG1 and MG2 to the HVECU 70 as necessary. The motor ECU 40 also calculates the rotational angular velocities ωm1, ωm2 and the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44. ing.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The battery ECU 52 is attached to a signal necessary for managing the battery 50, for example, an inter-terminal voltage Vb from a voltage sensor installed between the terminals of the battery 50 or an electric power line connected to the output terminal of the battery 50. The charging / discharging current Ib from the current sensor, the battery temperature Tb from the temperature sensor attached to the battery 50, and the like are input, and data on the state of the battery 50 is transmitted to the HVECU 70 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 is a power storage that is a ratio of the capacity of the electric power that can be discharged from the battery 50 at that time based on the integrated value of the charge / discharge current Ib detected by the current sensor. The ratio SOC is calculated, and the input / output limits Win and Wout, which are allowable input / output powers that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input limiting limit are set based on the storage ratio SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  As shown in FIG. 2, the voltage waveform output circuit 60 includes an oscillator 61 that is grounded to generate a pulse signal of a predetermined frequency, a detection resistor 62 that has one terminal connected to the oscillator 61, and one terminal that A coupling capacitor 63 is connected to the other terminal of the detection resistor 62 and the other terminal is connected to the connection point Cn. One terminal is grounded via the resistor 64 and the other terminal is connected to the detection resistor 62. A transistor 65 connected to a connection point Co with the coupling capacitor 63, a band-pass filter 66 having one terminal connected to the connection point Co and passing a component in a frequency band corresponding to the frequency of the pulse signal of the oscillator 61; A voltage detector 67 that detects an output value (voltage) after passing through the band-pass filter 66 and outputs the output value (voltage) to the HVECU 70. The HVECU 70 uses the voltage waveform from the voltage detector 67 to reduce the resistance value of the insulation resistance 69 with respect to the ground (vehicle body) of the circuit including the motors MG1, MG2, the inverters 41, 42, and the battery 50 (leakage of electricity). Whether or not there is a risk of Therefore, the combination of the voltage waveform output circuit 60 and the HVECU 70 can be considered as a leakage detection device 59 that determines whether or not the resistance value of the insulation resistance 69 is lowered (there is a risk of leakage).

  In this leakage detection device 59, when the transistor 65 is off, the voltage detector 67 has a small voltage drop at the detection resistor 62 when the resistance value of the insulation resistor 69 is not decreased (there is no risk of leakage). Therefore, when a voltage waveform having substantially the same amplitude as that of the oscillator 61 is detected and output to the HVECU 70 and the resistance value of the insulation resistor 69 is reduced (there is a risk of electric leakage), the voltage drop at the detection resistor 62 is large. Therefore, a voltage waveform having a somewhat smaller amplitude than that of the oscillator 61 is detected and output to the HVECU 70. Therefore, the HVECU 70 determines that the resistance value of the insulation resistor 69 is normal when the amplitude of the voltage waveform from the voltage detector 67 is equal to or greater than the threshold for determination slightly smaller than the amplitude of the voltage waveform of the oscillator 61, and the voltage detector 67. When the amplitude of the voltage waveform from is less than the threshold for determination, it is determined that the resistance value of the insulation resistor 69 is lowered (abnormal).

  In this leakage detection device 59, the transistor 65 is turned on and a resistor 64 having a relatively small resistance value is connected to the connection point Co to simulate a case where the circuit is leaking. In this state, the HVECU 70 By determining whether or not the amplitude of the voltage waveform from the voltage detector 67 is reduced as expected (below the above threshold for determination), the leakage detection is normally performed (leakage detection device). A self-diagnosis is performed to determine whether or not 59 functions normally. In the first embodiment, the self-diagnosis of the leakage detecting device 59 is performed by detecting the voltage over several tens of seconds to one minute after turning on the transistor 65 after several seconds to several tens of seconds have passed since the ignition was turned on (system activation). The voltage waveform is output from the device 67 to the HVECU 70, and the HVECU 70 determines whether or not the amplitude of the voltage waveform from the voltage detector 67 is reduced as expected.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. The HVECU 70 includes a voltage waveform from the voltage detector 67, an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator that detects the amount of depression of the accelerator pedal 83. The accelerator opening Acc from the pedal position sensor 84, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. . From the HVECU 70, an on / off signal to the transistor 65 is output via an output port. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  In addition, motors MG1 and MG2, inverters 41 and 42, a battery 50, a leakage detection device 59, and a motor ECU 40 correspond to the driving device of the embodiment.

  In the hybrid vehicle 20 of the first embodiment configured as described above, the required torque Tr * to be output to the drive shaft 36 is calculated based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal by the driver. The operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque Tr * is output to the drive shaft 36. As the operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the power corresponding to the required power is output from the engine 22, and all the power output from the engine 22 is transmitted to the planetary gear 30 and the motor. The torque conversion operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that the torque is converted by the MG1 and the motor MG2 and output to the drive shaft 36, and the sum of the required power and the power required for charging and discharging the battery 50 is met. Operation of the engine 22 is controlled so that power is output from the engine 22, and all or part of the power output from the engine 22 with charge / discharge of the battery 50 is torque generated by the planetary gear 30, the motor MG1, and the motor MG2. The required power is output to the drive shaft 36 with conversion. Charge-discharge drive mode for driving and controlling the motors MG1 and MG2, there is a motor operation mode in which operation control to output a power commensurate to stop the operation of the engine 22 to the required power from the motor MG2 to the drive shaft 36. The torque conversion operation mode and the charge / discharge operation mode are modes in which the engine 22, the motor MG1, and the motor MG2 are controlled so that the required power is output to the drive shaft 36 with the operation of the engine 22. Since there is no substantial difference in control, both are hereinafter referred to as the engine operation mode.

  In the engine operation mode, the HVECU 70 sets the required torque Tr * to be output to the drive shaft 36 based on the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88, and the set required torque Multiply Tr * by the rotational speed Nr of the drive shaft 36 (for example, the rotational speed Nm2 of the motor MG2 or the rotational speed obtained by multiplying the vehicle speed V by the conversion factor) to calculate the traveling power Pdrv * required for traveling, The required power Pe * as the power to be output from the engine 22 is set by subtracting the charge / discharge required power Pb * (a positive value when discharging from the battery 50) from the calculated traveling power Pdrv *. Then, the target rotational speed Ne of the engine 22 is obtained using an operation line (for example, a fuel efficiency optimal operation line) as a relationship between the rotational speed Ne of the engine 22 and the torque Te that can efficiently output the required power Pe * from the engine 22. * And the target torque Te * are set, and the motor is controlled by the rotational speed feedback control so that the rotational speed Ne of the engine 22 becomes the target rotational speed Ne * within the range of the input / output limits Win and Wout of the battery 50. A torque command Tm1 * as a torque to be output from MG1 is set, and when the motor MG1 is driven by the torque command Tm1 *, the torque acting on the drive shaft 36 via the planetary gear 30 is subtracted from the required torque Tr * to reduce the motor MG2. Torque command Tm2 * is set, and the target rotational speed Ne * and target torque Te * are set. In its sent to the engine ECU 24, the torque command Tm1 *, the Tm2 * is sent to the motor ECU 40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te *, controls the intake air amount, fuel injection control, and ignition of the engine 22 so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *. Control and so on. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * performs switching control of the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. By such control, it is possible to travel while outputting the required torque Tr * to the drive shaft 36 within the range of the input / output limits Win and Wout of the battery 50 while operating the engine 22 efficiently. In this engine operation mode, the stop condition of the engine 22 is satisfied, for example, when the required power Pe * has reached the stop threshold value Pstop defined as the upper limit of the range of the required power Pe * that should be stopped. Sometimes, the operation of the engine 22 is stopped and the operation mode is shifted to the motor operation mode.

  In the motor operation mode, the HVECU 70 sets a required torque Tr * to be output to the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, sets a value 0 to the torque command Tm1 * of the motor MG1, and sets the battery 50. The torque command Tm2 * of the motor MG2 is set and transmitted to the motor ECU 40 so that the required torque Tr * is output to the drive shaft 36 within the range of the input / output limits Win, Wout. Then, the motor ECU 40 that receives the torque commands Tm1 * and Tm2 * performs switching control of the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. With such control, the engine 22 can travel by outputting the required torque Tr * to the drive shaft 36 within the range of the input / output limits Win and Wout of the battery 50 with the engine 22 stopped. In this motor operation mode, the required power Pe * obtained by subtracting the charge / discharge required power Pb * of the battery 50 from the travel power Pdrv * obtained by multiplying the required torque Tr * by the rotational speed Nr of the drive shaft 36 is the engine 22. When the engine 22 start condition is satisfied, for example, when the engine reaches a start threshold value Pstart defined as the lower limit of the required power Pe * range, the engine 22 is started and the engine operation mode is entered. To do.

  Here, control of the inverters 41 and 42 will be described. In the first embodiment, the inverters 41 and 42 are controlled by pulse width modulation control that adjusts the ratio of the on-time of the switching elements of the inverters 41 and 42 by comparing the modulated wave (carrier wave) with the voltage command of the motors MG1 and MG2. To do. Here, the execution carrier frequencies f1 * and f2 * as the frequencies of the modulated waves are within the frequency ranges fext1 and fext2 that are spread by the spread frequencies fspr1 and fspr2 around the basic carrier frequencies f1 and f2, respectively. It is a frequency that changes periodically and randomly. The basic carrier frequencies f1 and f2 may be fixed values determined in advance (for example, 2 kHz, 4 kHz, 8 kHz, etc.), the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2, and the rotational speeds Nm1 and Nm2. A value based on the above may be used. Further, for example, 100 Hz, 200 Hz, 250 Hz, or the like can be used as the spreading frequencies fspr1, fspr2.

  Next, the operation of the hybrid vehicle 20 of the first embodiment configured as described above, particularly the control of the inverters 41 and 42 during the self-diagnosis of the leakage detection device 59 will be described. FIG. 3 is a flowchart showing an example of a carrier frequency setting routine for execution during self-diagnosis that is repeatedly (periodically) executed by the motor ECU 40 during self-diagnosis of the leakage detection device 59.

  When the carrier frequency setting routine during the self-diagnosis is executed, the motor ECU 40 sets the coefficient k to a value that is sequentially derived from a random number sequence that is discontinuous and has no regularity in the range of (−1, 1). Is set (step S100), and the carrier frequency f1 * for execution of the inverter 41 is set by adding the product of the set coefficient k to the spread frequency fspr1 to the basic carrier frequency f1 as shown in the following equation (1) ( In step S110), as shown in equation (2), the execution carrier frequency f2 * of the inverter 42 is set by subtracting the predetermined value α from the set execution carrier frequency f1 * (step S120), and this routine ends. To do. When the execution carrier frequencies f1 * and f2 * are set in this way, switching control of the switching elements of the inverters 41 and 42 is performed by pulse width modulation control using the modulation waves of the set execution carrier frequencies f1 * and f2 *. Here, for the predetermined value α, a value slightly larger than the upper limit of the range in which the proximity of the execution carrier frequencies f1 * and f2 * may cause noise in the self-diagnosis of the leakage detection device 59 may be used. For example, 30 Hz, 50 Hz, 70 Hz, or the like can be used.

f1 * = f1 + k ・ fspr1 (1)
f2 * = f1-α (2)

  FIG. 4 is an explanatory diagram showing an example of a temporal change in the execution carrier frequencies f1 * and f2 * during the self-diagnosis of the leakage detection device 59. In FIG. If the execution carrier frequencies f1 * and f2 * of the inverters 41 and 42 are close to each other during the self-diagnosis of the leakage detection device 59, the potential fluctuation at the connection point Cn (see FIG. 2) is a noise against the self-diagnosis of the leakage detection device 59. Thus, there is a risk that this self-diagnosis cannot be performed properly (incorrect diagnosis). On the other hand, in the first embodiment, the processing in steps S110 and S120 described above can prevent the execution carrier frequencies f1 * and f2 * from being close to each other as shown in FIG. Self-diagnosis can be performed more appropriately. Moreover, since the execution carrier frequencies f1 * and f2 * are changed every time the routine is executed (periodically), the operation noise (switching noise) of the inverters 41 and 42 increases during the self-diagnosis of the leakage detection device 59. Can be suppressed.

  According to the hybrid vehicle 20 of the first embodiment described above, during the self-diagnosis of the leakage detection device 59, the execution carrier frequencies f1 * and f2 * of the inverters 41 and 42 are different from the predetermined value α. Therefore, the self-diagnosis of the leakage detection device 59 can be performed more appropriately, and an increase in operating noise of the inverters 41 and 42 during the self-diagnosis can be suppressed.

  In the hybrid vehicle 20 of the first embodiment, the execution carrier frequencies f1 * and f2 * are periodically changed so that the execution carrier frequency f1 * is larger than the execution carrier frequency f2 * by a predetermined value α. The execution carrier frequencies f1 * and f2 * may be periodically changed so that the execution carrier frequency f1 * is smaller than the execution carrier frequency f2 * by a predetermined value α.

  Next, a hybrid vehicle 20B as a second embodiment of the present invention will be described. The hybrid vehicle 20B of the second embodiment has the same hardware configuration as the hybrid vehicle 20 of the first embodiment described with reference to FIGS. Therefore, in order to avoid redundant description, detailed description of the hardware configuration of the hybrid vehicle 20B of the second embodiment is omitted.

  In the hybrid vehicle 20B of the second embodiment, the motor ECU 40 performs the self-diagnosis execution illustrated in FIG. 5 instead of the self-diagnosis execution carrier frequency setting routine of FIG. The carrier frequency setting routine is executed repeatedly (periodically).

  When the self-diagnosis execution carrier frequency setting routine of FIG. 5 is executed, the motor ECU 40 first inputs the inverter temperature Tinv1 from the temperature sensor 45 (step S200), within the range of (−1, 1). Values that are sequentially derived from two random number sequences that have an average value of 0 and are discontinuous and have no regularity are set as coefficients k1 and k2 (step S210).

  Subsequently, the value of the temperature rise flag F is examined (step S220). Here, the temperature rise flag F is set to a value of 0 as an initial value at the start of self-diagnosis of the leakage detection device 59, and then set to a value of 1 when the inverter temperature Tinv1 reaches a predetermined temperature Tref1 or higher. It is. As the predetermined temperature Tref1, a temperature that is somewhat lower than the allowable upper limit temperature of the inverter 41 can be used.

  When the flag F is 0, the inverter temperature Tinv1 is compared with the predetermined temperature Tref1 (step S230). When the inverter temperature Tinv1 is lower than the predetermined temperature Tref1, the frequency Fref (for example, 3.5 kHz, 4 kHz, 5 kHz, etc.) is set. A frequency obtained by adding the spreading frequency fspr1 is set as the basic carrier frequency f1 (step S240), and a frequency obtained by subtracting the predetermined value α and the spreading frequency fspr2 from the predetermined frequency fref is set as the basic carrier frequency f2 (step S250). As shown in the following equation (3), the effective carrier frequency f1 * of the inverter 41 is set by adding the coefficient k1 multiplied by the spread frequency fspr1 to the basic carrier frequency f1 (step S260), and the equation (4) As shown in FIG. Added are multiplied in spr2 the fundamental carrier frequency f2 to set the execution carrier frequency f2 of the inverter 41 * (step S270). When the execution carrier frequencies f1 * and f2 * are set in this way, switching control of the switching elements of the inverters 41 and 42 is performed by pulse width modulation control using the modulation waves of the set execution carrier frequencies f1 * and f2 *.

  Through the processing in steps S240 to S270, the execution carrier frequency f1 * becomes a frequency within a range equal to or higher than the predetermined frequency fref, and the execution carrier frequency f2 * is a frequency (fref−α that is smaller than the predetermined frequency fref by a predetermined value α). ) The frequency is within the following range. Therefore, by periodically executing the processes of steps S240 to S270, the execution carrier frequency f1 * is periodically changed within a range equal to or higher than the predetermined frequency fref, and the execution carrier frequency f2 * is changed to the frequency (fref− α) It is changed periodically within the following range. Hereinafter, this is referred to as first pattern processing. By executing the first pattern processing, the self-diagnosis of the leakage detecting device 59 can be performed more appropriately and the operation sound of the inverters 41 and 42 becomes loud during the self-diagnosis, as in the first embodiment. Can be suppressed. The inverters 41 and 42 are inverters when driven using a modulated wave (carrier wave) having a carrier frequency in a high frequency region as compared to driving using a modulated wave (carrier wave) having a carrier frequency in a low frequency region. Temperature tends to rise.

  When the inverter temperature Tinv1 reaches the predetermined temperature Tref1 or more in step S230 while the routine (steps S200 to S270) is repeatedly executed in this way, the temperature rise flag F is set to a value 1 (step S280). A frequency obtained by subtracting the predetermined value α and the spread frequency fspr1 from the predetermined frequency fref is set as the basic carrier frequency f1 (step S290), and a frequency obtained by adding the spread frequency fspr2 to the predetermined frequency fref is set as the basic carrier frequency f2 ( In step S300, as shown in the above-described equation (3), the frequency obtained by multiplying the spread frequency fspr1 by the coefficient k1 is added to the basic carrier frequency f1 to set the execution carrier frequency f1 * of the inverter 41 (step S310). , Coefficient k2 as shown in equation (4) above It is multiplied to the spreading frequency fspr2 in addition to the basic carrier frequency f2 to set the execution carrier frequency f2 * of an inverter 42 (step S320). Through the processing in steps S290 to S320, the execution carrier frequency f1 * becomes a frequency within the range of the frequency (fref−α) or less, and the execution carrier frequency f2 * becomes a frequency within the range of the predetermined frequency fref or more. . Therefore, by periodically executing the processes in steps S290 to S320, the execution carrier frequency f1 * is periodically changed within the range of the frequency (fref-α) or less, and the execution carrier frequency f2 * is set to a predetermined value. The frequency is periodically changed within the range of the frequency fref or higher. Hereinafter, this is referred to as second pattern processing. By executing the second pattern processing, the self-diagnosis of the leakage detection device 59 can be performed more appropriately, and an increase in the operating noise of the inverters 41 and 42 during the self-diagnosis can be suppressed. Furthermore, an excessive temperature rise of the inverter 41 can be suppressed.

f1 * = f1 + k1 ・ fspr1 (3)
f2 * = f2 + k2 ・ fspr2 (4)

  FIG. 6 is an explanatory diagram illustrating an example of a temporal change in the inverter temperature Tinv1 and the execution carrier frequencies f1 * and f2 * during the self-diagnosis of the leakage detection device 59 of the second embodiment. In this modification, when the self-diagnosis of the leakage detecting device 59 is started, the execution carrier frequency f1 * is periodically changed within a range equal to or higher than the predetermined frequency fref and the execution carrier frequency f2 * is changed to the frequency (fref− α) Change periodically within the following range. When inverter temperature Tinv1 reaches or exceeds predetermined temperature Tref1 (time t1), thereafter, execution carrier frequency f1 * is periodically changed within a range of frequency (fref-α) or less and execution carrier frequency f2 is set. * Is periodically changed within a range of a predetermined frequency fref or more. Thereby, self-diagnosis of leakage detecting device 59 can be performed more appropriately, and increase in operating noise of inverters 41 and 42 during this self-diagnosis can be suppressed. Moreover, the excessive temperature rise of the inverter 41 can be suppressed.

  According to the hybrid vehicle 20B of the second embodiment described above, during the self-diagnosis of the leakage detection device 59, first, the execution carrier frequency f1 * is periodically changed and executed within a range equal to or higher than the predetermined frequency fref. After executing the first pattern processing for periodically changing the carrier frequency f2 * within the range of the frequency (fref-α) or less and the inverter temperature Tinv1 reaches the predetermined temperature Tref1 or higher, the execution carrier frequency f1 * Since the second pattern processing is executed to periodically change the effective carrier frequency f2 * within the range equal to or higher than the predetermined frequency fref while periodically changing the frequency within the range below the frequency (fref-α), the leakage detecting device 59 self-diagnosis can be performed more appropriately, and the operation sound of the inverters 41 and 42 is loud during this self-diagnosis. It can be suppressed, and an excessive temperature rise of the inverter 41 can be further suppressed.

  In the hybrid vehicle 20B of the second embodiment, during the self-diagnosis of the leakage detection device 59, first, the first pattern processing is executed, and after the inverter temperature Tinv1 from the temperature sensor 45 reaches the predetermined temperature Tref1 or higher, The second pattern process is executed. First, the second pattern process is executed. After the inverter temperature Tinv2 from the temperature sensor 46 reaches the predetermined temperature Tref2 or more, the first pattern process is executed. Also good. As the predetermined temperature Tref2, a temperature that is somewhat lower than the allowable upper limit temperature of the inverter 42 can be used. In this case, the self-diagnosis of the leakage detection device 59 can be performed more appropriately, and the operation noise of the inverters 41 and 42 can be prevented from becoming loud during the self-diagnosis. Temperature rise can be suppressed.

  In the hybrid vehicle 20B of the second embodiment, the first pattern process is first executed, and after the inverter temperature Tinv1 from the temperature sensor 45 reaches the predetermined temperature Tref1 or higher, the second pattern process is executed. First, the first pattern process may be executed, and after the first predetermined time (for example, several tens of seconds) has elapsed since the start of the execution, the second pattern process may be executed. In addition, first, the second pattern process may be executed, and after the second predetermined time (for example, several tens of seconds) has elapsed since the start of the execution, the first pattern process may be executed.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the voltage waveform output circuit 60 is connected to the negative electrode side of the battery 50. However, the voltage waveform output circuit 60 is connected to the positive electrode side of the battery 50. It is good also as what to do.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the power from the motor MG2 is output to the drive shaft 36. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. The power from MG2 may be output to an axle (an axle connected to wheels 39a and 39b in FIG. 7) different from an axle (an axle connected to drive wheels 38a and 38b) to which drive shaft 36 is connected. Good.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the power from the engine 22 is output to the drive shaft 36 connected to the drive wheels 38a and 38b via the planetary gear 30, but FIG. As illustrated in the hybrid vehicle 220 of the modified example, the inner rotor 232 connected to the crankshaft of the engine 22 and the outer rotor 234 connected to the drive shaft 36 that outputs power to the drive wheels 38a and 38b are included. A counter-rotor motor 230 that transmits a part of the power from the engine 22 to the drive shaft 36 and converts the remaining power into electric power may be provided.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the engine 22, the motor MG1, the drive shaft 36 connected to the drive wheels 38a and 38b, the planetary gear 30 connected to the engine 22 and the motor MG1. 9 and a battery 50 that exchanges electric power with the motors MG1 and MG2, the so-called parallel hybrid vehicle is configured. As described above, the engine 22, the generator 330 that generates power using the power from the engine 22, the motor MG connected to the drive wheels 38a and 38b, the battery 50 that exchanges power with the generator 330 and the motor MG, It is good also as a structure of what is called a series hybrid vehicle provided with.

  In the hybrid vehicles 20 and 20B of the first and second embodiments, the engine 22, the motor MG1, the drive shaft 36 connected to the drive wheels 38a and 38b, the planetary gear 30 connected to the engine 22 and the motor MG1. 10 and a battery 50 that exchanges electric power with the motors MG1 and MG2 and is configured as a hybrid vehicle. However, as illustrated in an electric vehicle 420 of a modification of FIG. The electric vehicle may include a motor MG connected to the drive wheels 38a and 38b, a motor MGR connected to the wheels 39a and 39b, and a battery 50 that exchanges power with the motors MG and MGR.

  In the first embodiment, the second embodiment, and these modifications, the hybrid vehicle and the electric vehicle have been described. However, the embodiment is mounted on a moving body such as an automobile and other vehicles (for example, a train), a ship, and an aircraft. The drive device may be in the form of a drive device incorporated in a facility that is not a moving body such as a construction facility.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the first and second embodiments, the motor MG1 corresponds to the “first motor”, the inverter 41 corresponds to the “first inverter”, the motor MG2 corresponds to the “second motor”, and the inverter 42 Corresponding to “second inverter”, battery 50 corresponds to “battery”, and leakage detection device 59 as a combination of voltage waveform output circuit 60 and HVECU 70 corresponds to “leakage detection device”.

  In the first embodiment, during the self-diagnosis of the leakage detection device 59, the carrier frequency setting routine for execution during self-diagnosis in FIG. 3 is periodically executed to execute the carrier frequencies f1 * and f2 * for the inverters 41 and 42. And the switching elements of the inverters 41 and 42 by the pulse width modulation control using the modulated waves of the execution carrier frequencies f1 * and f2 * set in this routine. The motor ECU 40 that performs the switching control corresponds to “control means”.

  In the second embodiment, during the self-diagnosis of the leakage detection device 59, the carrier frequency setting routine for execution during self-diagnosis in FIG. 5 is periodically executed. First, the carrier frequency for execution f1 * is equal to or higher than the predetermined frequency fref. The first pattern processing is performed in which the execution carrier frequency f2 * is periodically changed within the range and the execution carrier frequency f2 * is periodically changed within the range of the frequency (fref-α) or less, and the inverter temperature Tinv1 reaches the predetermined temperature Tref1 or higher. Thereafter, the execution carrier frequency f1 * is periodically changed within the range of the frequency (fref−α) or less, and the execution carrier frequency f2 * is periodically changed within the range of the predetermined frequency fref or more. In addition to executing pattern processing, pulse width modulation control is performed using the modulated waves of the execution carrier frequencies f1 * and f2 * set in this routine. Thus, the motor ECU 40 that performs switching control of the switching elements of the inverters 41 and 42 corresponds to “control means”.

  Here, the “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor. The “first inverter” is not limited to the inverter 41, and may be any type of inverter as long as it drives the first motor. The “second motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor. The “second inverter” is not limited to the inverter 42 and may be any type of inverter as long as it drives the second motor. The “battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and is electrically connected to the first inverter and the second inverter, such as a nickel hydride secondary battery, a nickel cadmium secondary battery, and a lead storage battery. Any type of battery may be used as long as it is connected electrically. The “leakage detection device” is not limited to the leakage detection device 59 as a combination of the voltage waveform output circuit 60 and the HVECU 70, and is connected to the positive side or the negative side of the battery to detect leakage of the circuit. Any type of leakage detection device may be used. As the “control means”, during the self-diagnosis of the leakage detection device 59, the carrier frequencies f1 * and f2 * for execution of the inverters 41 and 42 are periodically changed so that the difference between them becomes a predetermined value α. During the self-diagnosis of the leakage detection device 59, first, the execution carrier frequency f1 * is periodically changed within a range equal to or higher than the predetermined frequency fref, and the execution carrier frequency f2 * is within a range equal to or lower than the frequency (fref-α). After the inverter pattern Tinv1 reaches the predetermined temperature Tref1 or higher, the execution carrier frequency f1 * is periodically changed within the range of the frequency (fref−α) or less. It is limited to the one that changes the execution carrier frequency f2 * and periodically changes the execution carrier frequency f2 * within a range equal to or higher than the predetermined frequency fref. Instead, the first inverter is controlled by pulse width modulation control using the first modulated wave whose frequency changes periodically, and the second inverter is pulse widthed using the second modulated wave whose frequency changes periodically. Controlled by modulation control, and during the self-diagnosis of the leakage detecting device, the frequency of the first modulated wave and the frequency of the second modulated wave are periodically changed within a range where the difference between them is not less than a predetermined value. Anything can be used.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of drive devices.

  20, 120, 220, 320 Hybrid vehicle, 22 engine, 23 crank position sensor, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 36 drive shaft, 37 differential gear, 38a, 38b drive wheel, 39a, 39b Wheel, 40 Motor electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 45, 46 Temperature sensor, 50 Battery, 52 Battery electronic control unit (battery ECU), 59 Leakage detector, 60 voltage waveform output circuit, 61 oscillator, 62 detection resistor, 63 coupling capacitor, 64 resistor, 65 transistor, 66 band-pass filter, 67 voltage detector, 69 insulation resistance, 70 c Electronic control unit (HVECU) for bridging, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 230 to rotor motor 232 inner rotor, 234 outer rotor, 330 generator, 420 electric vehicle, MG, MGR, MG1, MG2 motor.

Claims (3)

A first motor, a first inverter that drives the first motor, a second motor, a second inverter that drives the second motor, and the first inverter and the second inverter electrically connected A battery, a leakage detection device connected to the positive side or the negative side of the battery to detect leakage of the circuit, and the first inverter using pulse width modulation control using a first modulated wave whose frequency changes periodically Control means for controlling the second inverter by pulse width modulation control using a second modulated wave that is controlled and periodically changes in frequency, and a drive device comprising:
During the self-diagnosis of the leakage detection device, the control means periodically changes the frequency of the first modulated wave and the frequency of the second modulated wave within a range in which the difference between them is not less than a predetermined value. Is a means to
A drive device characterized by that. The drive device according to claim 1,
The control means periodically changes one of the frequency of the first modulated wave and the frequency of the second modulated wave within a range equal to or higher than a first predetermined frequency during self-diagnosis of the leakage detection device. In addition, the first pattern processing is performed in which the other is periodically changed within the range of the second predetermined frequency that is smaller than the first predetermined frequency by the predetermined value, and then the one is within the range of the second frequency or less. The second pattern processing is performed for periodically changing the other and periodically changing the other within the range of the first predetermined frequency or higher.
Drive device. The drive device according to claim 2,
When the temperature of the inverter corresponding to the one of the first inverter and the second inverter reaches a predetermined temperature or more during execution of the first pattern processing, the control means Means for switching from the first pattern process to the second pattern process;
Drive device.

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