MOTOR VEHICLE

Abstract

Motor vehicle that features: a motor-driven generator motor (MG2) configured to input and output power for driving, an inverter (42) configured to drive the motor-driven generator motor (MG2), a battery (50) configured to transfer electrical energy to and from the motor-driven generator motor (MG2), a system main relay (55) configured to connect and disconnect the battery (50) from a power line on the inverter side (42), and a control device (40, 52, 70) configured to enable the motor vehicle to be driven by switching on the system main relay (55) according to a predetermined procedure as a response to a system-on operation, wherein the control device (40, 52, 70) does not perform a fault diagnosis of the inverter (42) if an abnormality signal of the inverter (42) is generated before a predetermined time after the system main relay (55) has been switched on as feedback to the system being on, while the fault diagnosis is performed if the abnormality signal of the inverter (42) is generated after the predetermined time, the motor vehicle also exhibits: an internal combustion engine (22), a generator-driven generator motor (MG1) configured to generate electrical energy using energy from the internal combustion engine (22), and an inverter (41) for the generator-driven generator motor (MG1) which is configured to drive the generator-driven generator motor (MG1), the inverter (42) is an inverter (42) for the motor-driven generator motor (MG2) which is configured to use two or more switching elements which are connected in parallel and are switched on and off simultaneously, the battery (50) is configured to transfer electrical energy to and from the generator-driven generator motor (MG1), the control device (40, 52, 70) does not perform fault diagnosis of the inverter (42) for the motor-driven generator motor (MG2) and the inverter (41) for the generator-driven generator motor (MG1) if an abnormality signal of the inverter (42) for the motor-driven generator motor (MG2) or of the inverter (41) for the generator-driven generator motor (MG1) is generated before the predetermined time, while the fault diagnosis is performed if the abnormality signal of the inverter (42) for the motor-driven generator motor (MG2) or of the inverter (41) for the generator-driven generator motor (MG1) is generated after the predetermined time, The fault diagnosis includes diagnoses of whether one of the two or more switching elements connected in parallel in the inverter (42) for the motor-driven generator motor (MG2) has an open fault, and the predetermined time is a point in time when permission is granted to switch the inverter (41) for the generator-driven generator motor (MG1) and the inverter (42) for the motor-driven generator motor (MG2).

Description

Technical field

[0001] The present invention relates to a motor vehicle, and more specifically to a motor vehicle equipped with an inverter configured to drive a motor that inputs and outputs power for driving. background

[0002] A proposed motor vehicle includes an internal combustion engine, two motor generators, and two inverters provided to drive the two motor generators, and is configured to determine whether any of the switching components included in the inverters has a fault (as described, for example, in JP 2010-68689 A). A motor control device determines whether a short-circuit fault of an upper arm or a lower arm occurs in one phase of multi-phase arms, and based on the result of this determination, executes simultaneous multi-phase on control that simultaneously turns on the upper arm or the lower arm of the multi-phase arms.

[0003] JP 2010-119268 A discloses a motor vehicle comprising: a motor configured to input and output power for driving, an inverter configured to drive the motor, an energy storage device configured to transmit electrical energy to and from the motor, a system main relay configured to connect and disconnect the energy storage device to and from a power line on the inverter side, and a control device configured to enable the motor vehicle to be driven with the turning on of the system main relay according to a predetermined procedure in response to a system-on operation, wherein the control device performs fault diagnosis of the inverter.

[0004] DE 11 2014 000 288 T5 discloses an inrush current suppression circuit provided in an electric power conversion device and suppressing an inrush current that occurs when power is turned on. The electric power conversion device includes an inverter circuit and a drive current circuit that generates direct voltages of two levels as drive voltages to be applied to a drive circuit of two switching elements included in the inverter circuit. The inrush current suppression circuit includes: an inrush current prevention resistor arranged between a converter circuit that generates a direct current to be applied to the inverter circuit and a smoothing circuit; a relay connected in parallel with the inrush current suppression resistor;and a relay control unit that applies a higher DC voltage from the DC voltages of the two levels to the relay to put the relay in a closed state, and after the relay is put in the closed state, applies a lower DC voltage from the DC voltages of the two levels to the relay to maintain the closed state;

[0005] US 2013 / 0 099 596 A1 discloses a control device of a power supply circuit, wherein the control device switches on a first system main relay connected to a first traction battery and a second system main relay connected to a second battery when an ignition switch is switched on, detects the voltages supplied by the batteries when the voltage applied to the corresponding inverters connected in parallel exceeds a first threshold value, and concludes that the respective relay is fixed to the respective battery when the corresponding battery voltage is higher than a second threshold value. Summary

[0006] Generally, inverter fault diagnosis is performed to identify an inverter fault when an abnormality signal (e.g., an overcurrent signal or an overvoltage signal) is detected from the inverter. Inverter fault diagnosis determines whether, for example, a short-circuit fault occurs in one of the three phases or an open-circuit fault occurs in one of the three phases. In many cases, a limitation is imposed on the drive control of a motor or generator. Immediately after a system start-up, an inverter abnormality signal may be detected due to noise or the like. Fault diagnosis performed in response to such an inverter abnormality signal is likely to produce an inappropriate diagnosis result because the motor vehicle is not in the stable driving state of the system.

[0007] Another proposed motor vehicle, with a view to driving the motor with high efficiency, includes an inverter configured to drive a motor for driving, which is an inverter comprising two or more switching components connected in parallel and simultaneously turned on and off to allow a large electric current to flow, and a boosting inverter configured to boost electric power from a battery and supply the boosted electric power to the inverter. An abnormality signal is detected due to, for example, an overcurrent when an open fault occurs in one of the two or more switching components connected in parallel.If fault diagnosis is performed based on the abnormality signal in the engine start mode by the generator immediately after a system-on operation, a limitation will be imposed on the drive control of the engine or generator. This may result in a voltage control failure of the boost converter.

[0008] The object of the invention is therefore to provide a motor vehicle that performs improved inverter fault diagnosis. This object is achieved by a motor vehicle having the features of claim 1. The dependent claims are directed to advantageous developments of the invention.

[0009] Thus, the motor vehicle can be driven with the system main relay turned on after the predetermined operation in response to the system-on operation. The motor vehicle does not perform the inverter fault diagnosis if the inverter abnormality signal is generated before the predetermined time after the system main relay is turned on in response to the system-on operation, while the fault diagnosis is performed if the inverter abnormality signal is generated after the predetermined time. This configuration suppresses the performance of the fault diagnosis based on an abnormality signal due to noise or the like. This predetermined operation may include, for example, precharging a smoothing capacitor connected to a positive bus bar and a negative bus bar of the inverter. The predetermined time is a time when permission to switch the inverter is given.This is because the abnormal signal generated before the inverter is allowed to switch on is likely due to noise or something similar. As a result, this configuration ensures more accurate inverter fault diagnosis.

[0010] In the motor vehicle of the above aspect, the motor vehicle may include a boost converter placed between the power storage device and the inverter, and configured to boost the electric power from the power storage device and supply the boosted electric power to the inverter, wherein the predetermined time is a time when permission is also given for control of the boost converter. This is because it is unlikely that fault diagnosis will be adequately performed in the case where permission is not given for control of the boost converter.

[0011] The motor vehicle includes an internal combustion engine, a generator configured to generate electric power using power of the internal combustion engine, and an inverter for the generator configured to drive the generator, wherein the inverter is an inverter for the motor configured to use two or more switching components connected in parallel and switched on and off simultaneously, wherein the power storage device is configured to transfer electric power to and from the generator, and wherein the control device does not perform the fault diagnosis of the inverter for the motor and the inverter for the generator if an abnormality signal of the inverter for the motor or the inverter for the generator is generated before the predetermined time during the fault diagnosis,If the abnormality signal is generated by the motor inverter or the generator inverter after the predetermined time, the fault diagnosis may include diagnosing whether any of the two or more parallel-connected switching components in the motor inverter have an open fault. This configuration ensures more appropriate fault diagnosis even if a switching component in one phase of the motor inverter has an open fault.

[0012] According to one embodiment, the control device does not perform the fault diagnosis if the abnormality signal of the motor inverter or the generator inverter is generated after the fault diagnosis diagnoses that a fault occurs in one of the inverters, the motor inverter or the generator inverter. Since a fault has already been identified by the fault diagnosis, there is no need to perform further fault diagnosis. Short description of the drawings Fig. 1 is a configuration diagram illustrating the schematic configuration of a hybrid vehicle 20 according to an embodiment of the invention. Fig. 2 is a configuration diagram showing the schematic configuration of an electrical system including the generator motors MG1 and MG2. Fig. 3 is a flowchart showing an example of a fault diagnosis process routine performed by an HVECU 70. Fig. 4 is a diagram illustrating an example of time changes in switching of a system main relay 55, a state of permission to switch inverters 41 and 42, a state of permission of boost control by a boost inverter 56, and execution of fault diagnosis. Fig. 5 is a configuration diagram illustrating the schematic configuration of a hybrid vehicle 120 after modification. Fig. 6 is a configuration diagram illustrating the schematic configuration of a hybrid vehicle 220 after another modification. Detailed description of the embodiments

[0013] The following describes some aspects of the present invention with reference to embodiments. Fig. 1 is a configuration diagram illustrating the schematic configuration of a hybrid vehicle according to an embodiment of the invention. As illustrated, the hybrid vehicle 20 of the embodiment includes an engine 22, an engine electronic control unit (hereinafter referred to as engine ECU) 24, a planetary gear train 30, a motor-driven generator motor MG1, a generator-driven generator motor MG2, inverters 41 and 42, an engine electronic control unit (hereinafter referred to as engine ECU) 40, a battery 50, a battery electronic control unit (hereinafter referred to as battery ECU) 52, a boost inverter 56, and a hybrid electronic control unit (hereinafter referred to as HVECU) 70.

[0014] The internal combustion engine 22 is configured as a common combustion engine to output power using, for example, premium gasoline or light oil as a fuel, and is driven and controlled by the internal combustion engine ECU 24. The internal combustion engine ECU 24 is configured as a CPU-based microprocessor and includes, in addition to the CPU, a ROM configured to store operation programs, a RAM configured to temporarily store data, input / output ports, and a communication port, although these are not shown.Signals from a plurality of sensors configured to detect the operating conditions of the internal combustion engine 22 are input to the internal combustion engine ECU 24 via the input port: for example, a crank position input Ocr input from a crank position sensor configured to detect the rotational position of a crankshaft 26, a cooling water temperature input Twe input from a cooling water sensor configured to detect the temperature of the cooling water of the internal combustion engine 22, an intake air amount Qa from an air flow meter mounted on an air intake pipe, and an intake air temperature Ta from a temperature sensor mounted on an air intake pipe.Several control signals for driving the engine 22 are output from the engine ECU 24 via the output port: for example, a drive signal to a fuel injection valve, a drive signal to a throttle motor configured to regulate the position of the throttle valve, and a control signal to an ignition coil integrated with an igniter. The engine ECU 24 communicates with the HVECU 70 to operate and control the engine 22 in response to a control signal from the HVECU 70, and to output data concerning the operating conditions of the engine 22 to the HVECU 70 as a required basis. The engine ECU 24 calculates a rotational speed of the crankshaft 26, that is, a rotational speed Ne of the engine 22, based on the signal input from the crank position sensor (not shown) attached to the crankshaft 26.

[0015] The planetary gear set 30 is configured as a single-pinion planetary gear mechanism. A sun gear, a ring gear, and a carrier of the planetary gear set 30 are connected to a rotor of the generator motor MG1, a drive shaft 36 coupled to the drive gears 39a and 39b via a differential gear 37, and the crankshaft 26 of the internal combustion engine 22, respectively.

[0016] The generator motor MG1 is configured as a known synchronous generator motor including a rotor with permanent magnets embedded therein and a stator with three-phase coils wound thereon. This rotor is connected to the sun gear of the planetary gear train 30 as described above. The generator motor MG2 is also configured as a synchronous generator motor like the generator motor MG1 and includes a rotor connected to the drive shaft 36. The engine ECU 40 controls the inverters 41 and 42 to drive the generator motors MG1 and MG2. The inverters 41 and 42 are connected via power grids (hereinafter referred to as the drive voltage system power grid) 54a to the boost converter 56, which is connected to power grids (hereinafter referred to as the battery voltage system power grid) 54b to which the battery 50 and a system main relay 55 are connected.As it is in . Fig. As shown in Figure 2, the inverter 41 includes six transistors T11 to T16 and six diodes D11 to D16 connected in parallel with the transistors T11 to T16 and in a reverse direction thereto. The transistors T11 to T16 are arranged in pairs such that two transistors in each pair respectively serve as a source relative to a positive bus bar and as a sink relative to a negative bus bar of the drive voltage system power networks 54a. Each phase of the three-phase coils (U-phase, V-phase, and W-phase) of the generator motor MG1 is connected to a connection point of each pair of transistors. Accordingly, when a voltage is applied to the inverter 41, the engine ECU 40 regulates the on-time ratio of the corresponding pair of transistors T11 to T16 to thereby provide a rotating magnetic field in the three-phase coils, thereby rotating and driving the generator motor MG1. As shown in Fig. As shown in Figure 2, the inverter 42 includes six pairs of transistors T21a, T21b, T22a, T22b, T23a, T23b, T24a, T24b, T25a, T25b, T26a, and T26b connected in parallel, and twelve diodes D21a, D21b through D26a, D26b connected in parallel to the transistors T21a, T21b through T26a, T26b and in a reverse direction. The six pairs of transistors T21a, T21b through T26a, T26b are arranged in series so that two pairs of transistors serve as a source to the positive power rail and a sink to the negative power rail of the drive voltage system power networks 54a, respectively. Each phase of the three-phase coils (U-phase, V-phase and W-phase) of the generator motor MG2 is connected to a connection point of the two pairs of transistors.Accordingly, when a voltage is applied to the inverter 42, the engine ECU 40 regulates the ratio of the on-time of the corresponding pairs of transistors on the source side (transistors T21a, T21b to T23a, T23b) and the corresponding pairs of transistors on the sink side (transistors T24a, T24b to T26a, T26b) to provide a rotating magnetic field in the three-phase coils to rotate and drive the generator motor MG2. Each pair of transistors T21a and T21b, ..., T26a and T26b is turned on and off simultaneously. The inverters 41 and 42 share the positive bus bar and the negative bus bar of the drive voltage system power grids 54a, so that electric power generated by one of the generator motors MG1 and MG2 can be supplied to the other generator motor MG1 or MG2.

[0017] As it is in Fig. As shown in Figure 2, the boost converter 56 is configured as a boost converter including two transistors T51 and T52, two diodes D51 and D52 connected in parallel with and in reverse to the transistors T51 and T52, and a reactor L. The two transistors T51 and T52 are connected to the positive busbar of the drive voltage system power networks 54a and to the negative busbar of the drive voltage system power networks 54a and a negative busbar of the battery voltage system power networks 54b, respectively. The reactor L is connected to a junction point of the transistors T51 and T52 and to a positive busbar of the battery voltage system power networks 54b.Accordingly, the transistors T51 and T52 are turned on and off to step up the electric power voltage of the battery voltage system power networks 54b and supply the electric power of the stepped-up voltage to the drive voltage system power networks 54a, and to step down the electric power voltage of the drive voltage system power networks 54a and supply the electric power of the stepped-down voltage to the battery voltage system power networks 54b.

[0018] A smoothing capacitor 57 for smoothing and a discharge resistor 58 for discharging are arranged in parallel and connected to the drive voltage system power networks 54a. The system main relay 55, which includes a positive-electrode-side relay SB, a negative-electrode-side relay SG, a precharge relay SP, and a precharge resistor RP, is placed on an output terminal side of the battery 50 in the battery voltage system power networks 54b. A filter capacitor 59 for smoothing is connected to the boost converter 56 side in the battery voltage system power networks 54b.

[0019] The engine ECU 40 is configured as a CPU-based microprocessor and includes, in addition to the CPU, a ROM configured to store operation programs, a RAM configured to temporarily store data, input / output ports, and a communication port, although these are not shown. Signals required for the drive control of the generator motors MG1 and MG2 are input to the engine ECU 40 via the input port: for example, rotation positions Θm1 and Θm2 from rotation position detection sensors 43 and 44 configured to detect the rotation positions of the respective rotors of the generator motors MG1 and MG2, and phase currents applied to the generator motors MG1 and MG2 and detected by current sensors (not shown). The input signals to the engine ECU 40 also include a voltage VG of the smoothing capacitor 57 (i.e.,The voltage of the drive system power supplies 54a (hereinafter referred to as the drive system voltage) is sensed by a voltage sensor 57a mounted between terminals of the smoothing capacitor 57, and the voltage VL of the filter capacitor 59 (i.e., the voltage of the battery system power supplies 54b (hereinafter referred to as the battery system voltage) is sensed by a voltage sensor 59a mounted between terminals of the filter capacitor 59. Control signals for driving the inverters 41 and 42 and the boost converter 56 are output from the engine ECU 40 via the output terminal: for example, switching control signals to the transistors T11 to T16 of the inverter 41 and the transistors T21 to T26 of the inverter 42, and switching control signals to the transistors T51 and T52 of the boost converter 56.The engine ECU 40 communicates with the HVECU 70 to drive and control the generator motors MG1 and MG2 in response to control signals from the HVECU 70, and to output data concerning the operating states of the generator motors MG1 and MG2 to the HVECU 70 as a required basis. The engine ECU 40 also calculates rotation speeds NM1 and Nm2 of the generator motors MG1 and MG2 based on the rotation positions Θm1 and Θm2, which are input from the rotation position detection sensors 43 and 44, of the respective rotors of the generator motors MG1 and MG2.

[0020] The battery 50 may be configured, for example, as a rechargeable lithium-ion battery and serves to transmit electrical power to and from the generator motors MG1 and MG2 via the inverters 41 and 42. The battery ECU 52, which serves to manage the battery 50, is configured as a CPU-based microprocessor and includes, in addition to the CPU, a ROM configured to store operation programs, a RAM configured to temporarily store data, input / output ports, and a communication port, although these are not shown.Signals required to manage the battery 50 are input to the battery ECU 52 via the input terminal: for example, a battery voltage Vb from a voltage sensor 51a mounted between terminals of the battery 50, a battery current Ib from a current sensor 51b mounted on the power grid connected to an output terminal of the battery 50, and a battery temperature Tb from a temperature sensor (not shown) mounted on the battery 50. The battery ECU 52 communicates with the HVECU 70 to send data concerning the conditions of the battery 50 to the HVECU 70 as a required basis through communication.With a view to managing the battery 50, the battery ECU 52 calculates a state of charge SOC indicating a ratio of the capacity of the electric power dischargeable from the battery 50 to the total capacity of the battery 50, based on an integrated value of the battery current Ib detected by the current sensor 51b, and calculates input and output limit values ​​Win and Wout indicating a maximum of the allowable electric powers chargeable to and dischargeable from the battery 50, based on the calculated state of charge SOC and the battery temperature Tb.

[0021] The HVECU 70 is configured as a CPU-based microprocessor and includes, in addition to the CPU, a ROM configured to store operation programs, a RAM configured to temporarily store data, input / output ports, and a communication port, although these are not shown. Several signals necessary for drive control are input to the HVECU 70 via the input port: for example, an ignition signal from an ignition switch 80 and a vehicle speed V from a vehicle speed sensor 88.The signals input to the HVECU 70 also include, for example, a shift position from a shift position sensor 82 configured to detect an operating position of a shift lever 81, an accelerator position ACC from an accelerator pedal position sensor 84 configured to detect a depression amount of an accelerator pedal 83, and a brake pedal position BP from a brake pedal position sensor 86 configured to detect a depression amount of a brake pedal 85. Control signals, for example, a drive signal to the system main relay 55, are output from the HVECU 70 via the output terminal.The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the corresponding communication ports as described above to transmit a plurality of control signals to and data from the engine ECU 24, the motor ECU 40, and the battery ECU 52.

[0022] The hybrid vehicle 20 of the embodiment having the above configuration can be driven in a hybrid drive mode (HV drive) or an electric drive mode (EV drive). The HV drive mode indicates a drive mode with operation of the internal combustion engine 22, and the EV drive mode indicates a drive mode without operation of the internal combustion engine 22.

[0023] The following describes operations of the hybrid vehicle 20 of the embodiment, and more specifically, a series of operations for diagnosing failures based on abnormality signals of the inverters 41 and 42. Fig. 3 is a flowchart showing an example of a fault diagnosis process routine performed by an HVECU.

[0024] When the fault diagnosis process routine is initiated, the HVECU 70 first determines (step S100) whether the ignition switch 80 is turned on by an operator. If the ignition switch 80 is not turned on, the HVECU 70 waits for an on operation of the ignition switch 80. If it is determined that the ignition switch 80 is turned on, the HVECU 70 then determines (step S110) whether permission has been given to switch the transistors T11 to T16 of the inverter 41 and the transistors T21a, T21b to T26a, T26b of the inverter 42, accompanied by the release of the gate blocking of the inverters 41 and 42.Permission to switch inverters 41 and 42 is given by subsequently turning on the ignition switch 80, turning on the positive-electrode-side relay SB and the precharge relay SP to precharge the filter capacitor 59 and the smoothing capacitor 57, turning on the negative-electrode-side relay SG, and turning off the precharge relay SP to make the vehicle ready (driveable) and release the gate blocking of inverters 41 and 42. If it is determined that permission to switch inverters 41 and 42 is not given, the HVECU 70 returns to step S100 of the process flow.

[0025] On the other hand, if it is determined in step S110 that permission is given to switch the inverters 41 and 42, the HVECU 70 subsequently determines (step S120) whether permission is given for boost control by the boost inverter 56. Permission may be given for boost control by the boost inverter 56, for example, if it is determined that a current sensor (not shown) configured to detect the electric current flowing in the reactor L, as well as the voltage sensors 57a and 59a, are normal, and that no failure occurs in the transistors T51 and T52. If it is determined that permission is not given for boost control by the boost inverter 56, the HVECU 70 returns to step S100 of the process flow.

[0026] On the other hand, if it is determined in step S120 that permission for boost control by boost inverter 56 is given, the HVECU 70 validates error signals (abnormality signals) that may subsequently be generated in inverters 41 and 42 (step S130). Accordingly, detected error signals (abnormality signals) of inverters 41 and 42 are determined to be invalid until permission is given to switch inverters 41 and 42 and permission is given for boost control by boost inverter 56 after an on-operation of the ignition switch 80. This configuration effectively addresses the detection of an error signal of inverter 41 or 42 due to noise or the like.For example, in the case of starting the internal combustion engine 22 simultaneously with the vehicle preparation, an open fault of one of the transistors T21a, T21b to T26a, T26b of the inverter 42 may cause a problem due to the fault diagnosis performed simultaneously with the start of the internal combustion engine 22, such as a problem of a fault in the voltage control of the drive voltage system power grids 54a by the boost converter 56 or a problem of a false diagnosis that the inverter 41 has a fault. This configuration reduces the possibility of such a problem occurring. The fault signal of the inverter 41 or 42 may be output when an overcurrent flows in one phase of the inverter 41 or 42, when an overcurrent flows in the drive voltage system power grids 54a, or when the smoothing capacitor 57 has an overvoltage.

[0027] The HVECU 70 then determines whether a fault signal from inverter 41 or 42 is detected (step S140). If no fault signal from inverter 41 or 42 is detected, the HVECU 70 waits for the detection of a fault signal. If a fault signal from inverter 41 or 42 is detected, the HVECU 70 performs fault diagnosis of inverters 41 and 42 (step S150). The fault diagnosis determines whether an on-fault occurs and determines whether an open fault occurs in any of transistors T11 to T16 of inverter 41 and transistors T21a, T21b to T26a, T26b of inverter 42. The fault diagnosis is performed by setting torque limits for generator motors MG1 and MG2 or setting switching limits for inverters 41 and 42 according to the type of fault. If no error is detected as a result of the error diagnosis (step S160), the HVECU 70 returns to step S140 of the process flow.On the other hand, if a fault is detected as a result of the fault diagnosis (step S160), the HVECU 70 invalidates the fault signals (abnormality signals) subsequently generated in the inverters 41 and 42 (step S170). When a fault occurs, emergency drive control is performed according to the location of the fault. Subsequent fault diagnosis is therefore considered unnecessary.

[0028] Fig. 4 is a graph illustrating an example of time changes in the switching of a system main relay, the status of permission to switch inverters, the status of permission for boost control by a boost converter, and the execution of fault diagnosis. The ignition switch 80 is turned on at time T1. At time T2, the system main relay 55 is turned on, and permission to switch inverters 41 and 42 is given. At time T3, permission for boost control by boost converter 56 is given. This validates fault signals of inverters 41 and 42 after time T3. Accordingly, even if a fault signal of inverter 41 or 42 is detected in a time period from time T1 to time T3, this detected fault signal is determined to be invalid, so fault diagnosis is not performed.When a fault signal of inverter 41 or 42 is detected at time T4, fault diagnosis of inverters 41 and 42 is performed in response to the detection of this fault signal. At time T5 upon completion of the fault diagnosis, emergency drive control is performed in response to the fault, and fault signals of inverters 41 and 42 detected thereafter are invalidated. Accordingly, even if a fault signal of inverter 41 or 42 is detected at time T6 thereafter, this detected fault signal is determined to be invalid, so fault diagnosis in response to the fault signal is not performed.

[0029] As described above, the hybrid vehicle 20 of the embodiment is configured not to perform fault diagnosis of the inverters 41 and 42 even if a fault signal of the inverters 41 or 42 is detected until permission is given for switching the inverters 41 and 42 and permission is given for boost control by the boost converter 56 after an on-operation of the ignition switch 80. This configuration prevents fault diagnosis from being performed in response to detection of a fault signal of the inverter 41 or 42 due to noise or the like. When a fault signal of the inverter 41 or 42 is detected after permission is given for boost control by the boost converter 56, this configuration performs fault diagnosis of the inverters 41 and 42 and detects a fault of the inverter 41 or 42. As a result, this ensures more appropriate fault diagnosis of the inverters 41 and 42.

[0030] The hybrid vehicle 20 of the embodiment is configured such that the engine 22 and the generator motor MG1 are connected via the planetary gear 30 to the drive shaft 36, which is coupled to the drive wheels 38a and 38b, and the generator motor MG2 is connected to the drive shaft 36. As shown in Fig. 5, the present invention can nevertheless be applied to a hybrid vehicle 120 of a modification configured such that a generator motor MG is connected to a drive shaft 36 coupled to the drive wheels 38a and 38b via a transmission 130, and an internal combustion engine 22 is connected to a rotating shaft of the generator motor MG via a clutch 129. As shown in Fig. 6, the present invention can also be applied to a hybrid vehicle 220 of another modification configured as a series hybrid vehicle such that a generator motor MG2 for driving is connected to a drive shaft 36 coupled to the drive wheels 38a and 38b, and a generator motor MG1 for power generation is connected to an output shaft of an internal combustion engine 22.

[0031] Although the hybrid vehicle 20 of the embodiment is equipped with the boost inverter 56, the hybrid vehicle may not be equipped with the boost inverter 56. In this modification, the process of step S120 may be omitted from the fault diagnosis process routine of Fig. 3 can be omitted. In the hybrid vehicle 20 of the embodiment, the battery 50 is connected to the battery voltage system power grids 54b. However, the battery 50 can be replaced with a capacitor.

[0032] The above embodiment describes an application of the invention to the hybrid vehicle 20. However, the present invention can be applied to a configuration of a vehicle, for example, an electric vehicle without an internal combustion engine, including a motor configured to input and output power for driving, an inverter configured to drive the motor, a power storage device configured to transfer electric power to and from the motor, a system main relay, and a control device configured to allow the vehicle to be driven with turning on the system main relay after a predetermined operation in response to a system-on operation.

[0033] The following describes the correspondence between the primary components of the above embodiment and the primary components of the invention described in the summary. The generator motors MG1 and MG2 of the embodiment correspond to the "motor" and the "generator," respectively, and the inverters 41 and 42 correspond to the "inverter." The battery 50 corresponds to the "power storage device," and the system main relay 55 corresponds to the "system main relay." The HVECU 70, among the HVECU 70, the motor ECU 40, the engine ECU 24, and the battery 52, mainly corresponds to the "control device."

[0034] The present invention is applicable to motor vehicle manufacturing industries.

Claims

[1] Motor vehicle which has: a motor-driven generator motor (MG2) configured to input and output power for driving, an inverter (42) configured to drive the engine-driven generator motor (MG2), a battery (50) configured to transfer electrical energy to and from the engine-driven generator motor (MG2), a system main relay (55) configured to connect and disconnect the battery (50) to and from a power line on the inverter (42) side, and a control device (40, 52, 70) configured to enable the motor vehicle to be driven with the switching on of the system main relay (55) according to a predetermined procedure in response to a system-on operation, wherein the control device (40, 52, 70) does not perform a fault diagnosis of the inverter (42) if an abnormality signal of the inverter (42) is generated before a predetermined time after the system main relay (55) is turned on as feedback to the system-on operation, while the fault diagnosis is performed if the abnormality signal of the inverter (42) is generated after the predetermined time, the motor vehicle also has: an internal combustion engine (22), a generator-driven generator motor (MG1) configured to generate electrical energy using energy from the internal combustion engine (22), and an inverter (41) for the generator-driven generator motor (MG1) configured to drive the generator-driven generator motor (MG1), the inverter (42) is an inverter (42) for the motor-driven generator motor (MG2) configured to use two or more switching elements connected in parallel and switched on and off simultaneously, the battery (50) is configured to transfer electrical energy to and from the generator-driven generator motor (MG1), the control device (40, 52, 70) does not carry out the fault diagnosis of the inverter (42) for the motor-driven generator motor (MG2) and the inverter (41) for the generator-driven generator motor (MG1) if an abnormality signal of the inverter (42) for the motor-driven generator motor (MG2) or the inverter (41) for the generator-driven generator motor (MG1) is generated before the predetermined time, while the fault diagnosis is carried out if the abnormality signal of the inverter (42) for the motor-driven generator motor (MG2) or the inverter (41) for the generator-driven generator motor (MG1) is generated after the predetermined time, the fault diagnosis includes diagnoses as to whether one switching element of the two or more switching elements connected in parallel in the inverter (42) for the motor-driven generator motor (MG2) has an open fault, and the predetermined time is a time when permission is given to switch the inverter (41) for the generator-driven generator motor (MG1) and the inverter (42) for the engine-driven generator motor (MG2). [2] A motor vehicle according to claim 1, wherein permission to switch the inverter (41) for the generator-driven generator motor (MG1) and the inverter (42) for the engine-driven generator motor (MG2) is granted by releasing a gate blocking of the inverters (41, 42). [3] A motor vehicle according to claim 1, further comprising: a boost converter (56) placed between the battery (50) and the inverter (42) for the motor-driven generator motor (MG2) and configured to boost the electrical energy from the battery (50) and supply the boosted electrical energy to the inverter (42) for the motor-driven generator motor (MG2), wherein the predetermined time is a time when permission to switch the inverter (41) for the generator-driven generator motor (MG1) and the inverter (42) for the motor-driven generator motor (MG2) is granted and permission to control the boost converter (56) is granted. [4] A motor vehicle according to claim 1, wherein the control device (40, 52, 70) does not perform the fault diagnosis when the abnormality signal of the inverter (42) for the motor-driven generator motor (MG2) or the inverter (41) for the generator-driven generator motor (MG1) is generated after the fault diagnosis diagnoses that a fault occurs in one of the inverters, inverter (42) for the motor-driven generator motor (MG2) or inverter (41) for the generator-driven generator motor (MG1).

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