JP2011147207A - Drive control system for electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly set a boosted voltage of a converter 48 by striking a balance between the improvement in system efficiency and the security in system controllability. <P>SOLUTION: A drive control system 10 includes a converter 48, inverters 44 and 46, motors MG1 and MG2, and a motor ECU60. The motor ECU60 includes a loss power deriver (S10-S28) which derives a total loss power in the converter 48, the inverters 44 and 46, and the motors MG1 and MG2 when a hybrid vehicle travels a specified travel pattern, a first boosted voltage deriver (S32, 34) which derives a first boosted voltage with which the total loss power becomes minimum, a second boosted voltage deriver (S36-S44) which derives a second boosted voltage requested from controllability of the motors MG1 and MG2, and a boosted voltage setter (S46) which sets a boosted voltage command by the converter 48 based on the first and second boosted voltage. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drive control system for an electric vehicle, and more particularly, from a converter capable of boosting a DC voltage from a DC power supply, an inverter capable of converting a boosted voltage output from the converter into an AC voltage, and an inverter. The present invention relates to a drive control system for an electric vehicle including a rotating electrical machine that is driven by being applied with an output AC voltage, and a control device that controls operations of a converter and an inverter.

  Conventionally, a hybrid vehicle including an engine and a motor as a driving power source is known. This hybrid vehicle is capable of so-called EV traveling that travels only with power obtained by driving a motor with electric power supplied from a vehicle-mounted battery with the engine stopped.

  In the hybrid vehicle, there is a type in which a DC voltage from a battery is boosted by a converter, converted into an AC voltage by an inverter, and applied to the motor. In this case, the battery voltage is boosted and used as a motor drive voltage, so that the motor can be driven in a high torque / high rotation region, and there is an advantage that the power performance of the vehicle is improved.

  On the other hand, in the converter, the battery voltage is boosted by performing on / off control of the power switching element, which is a component of the converter, at a high speed. The higher the boosted voltage, the greater the power loss associated with the switching.

  Similarly, in the motor, the induced voltage increases in the higher torque / high rotation range, so the voltage required for driving (hereinafter sometimes referred to as the motor required voltage) increases, and the power of the inverter increases accordingly. The loss power due to switching loss due to the switching element for the motor and the loss due to iron loss and copper loss in the motor also increase.

  Therefore, in a hybrid vehicle, it is important to minimize these power losses in order to improve energy efficiency and fuel consumption.

  For example, Japanese Unexamined Patent Application Publication No. 2007-325351 (Patent Document 1) discloses a motor drive control system including a converter configured to variably control a DC voltage and an inverter that converts the converter output voltage into an AC voltage. In order to improve efficiency, it is possible to estimate the power loss in the battery, converter, inverter and motor generator, and set the voltage value that minimizes the sum of the estimated power loss in the entire system as the boost voltage command value for the converter Are listed.

JP 2007-325351 A

  However, as described in Japanese Patent Application Laid-Open No. 2007-325351, when the boost voltage of the converter is set in consideration of only the power loss of the system, it is assumed that the controllability of the motor generator is often deteriorated. The boosted voltage by the converter is preferably set in consideration of not only the power loss in the converter, inverter and motor generator, but also the running pattern in which the vehicle equipped with the motor drive control system is used.

  An object of the present invention is to drive a converter capable of boosting a DC voltage from a DC power supply, an inverter capable of converting a boosted voltage output from the converter into an AC voltage, and an AC voltage output from the inverter. In a drive control system for an electric vehicle including a rotating electrical machine and a control device that controls the operation of the converter and the inverter, the boost voltage of the converter is appropriately set in consideration of both the vehicle running pattern and the controllability of the rotating electrical machine in a balanced manner Is to set.

  The present invention relates to a converter capable of boosting a DC voltage from a DC power supply, an inverter capable of converting a boosted voltage output from the converter into an AC voltage, and a rotating electrical machine driven by applying an AC voltage output from the inverter And a control device for controlling the operation of the converter and the inverter, the drive control system of the electric vehicle, wherein the control device, when the electric vehicle travels a predetermined travel pattern, the power loss in the converter and the A first loss power deriving unit for deriving a total loss power of a loss power in the inverter and a loss power in the rotating electrical machine; and a first boost voltage deriving for deriving a first boost voltage that minimizes the total loss power. A second boosted voltage deriving unit for deriving a second boosted voltage required from the controllability of the rotating electrical machine, the first and the second Based on the boosted voltage and a boosted voltage setting unit that sets a boost voltage command value by the converter.

  In the drive control system for an electric vehicle according to the present invention, the boost voltage calculation unit also calculates the sum of carrier frequencies, which is one of the parameters used to obtain the first boost voltage that minimizes the total loss power. A value that minimizes the power loss may be obtained.

  In the drive control system for an electric vehicle according to the present invention, the predetermined travel pattern is set via a typical travel pattern set in advance, a travel pattern set from a past travel history, and an in-vehicle navigation device. Any one of the running patterns may be used.

  According to the drive control system for an electric vehicle according to the present invention, the boosted voltage of the converter can be appropriately set in consideration of both improvement in system efficiency and ensuring of system controllability.

1 is a schematic configuration diagram of a hybrid vehicle equipped with a drive control system for an electric vehicle according to an embodiment of the present invention. It is a flowchart which shows the process sequence performed in a control apparatus. It is a flowchart which shows the process sequence performed in a control apparatus, and is a continuation of FIG.

  Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings. In this description, specific shapes, materials, numerical values, directions, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the application, purpose, specification, and the like.

  In the following, the drive control system of the present embodiment will be described by taking a hybrid vehicle further including, as an example of an electric vehicle, a hybrid vehicle further including a motor driven by electric power from a battery in addition to an engine that is an internal combustion engine. However, the present invention may be applied to a one-motor type hybrid vehicle or an electric vehicle including only a motor as a driving power source.

  FIG. 1 is a diagram showing a schematic configuration of a hybrid vehicle 1 equipped with an electric vehicle drive control system 10 (hereinafter, simply referred to as a drive control system as appropriate) according to an embodiment of the present invention. In FIG. 1, the power transmission system is indicated by a solid line, the power line is indicated by a one-dot chain line, and the signal line is indicated by a dotted line. Hybrid vehicle 1 includes an engine 12 capable of outputting driving power, two three-phase AC synchronous motors (rotating electrical machines) MG1 and MG2, and a power split mechanism 14.

  The engine 12 is an internal combustion engine that uses gasoline, light oil, or the like as fuel. The engine 12 is electrically connected to an engine ECU (Electronic Control Unit) (hereinafter referred to as “engine ECU”) 16 and receives a control signal from the engine ECU 16 to perform fuel injection, ignition, intake air amount, The operation or operation including starting and stopping is controlled by adjusting the intake valve timing and the like. A rotation angle sensor 11 is disposed close to the output shaft 13 connected to the crankshaft of the engine 12. The detection result of the rotation angle sensor 11 is input to the engine ECU 16 and used for calculation and monitoring of the engine speed Ne.

  The power split mechanism 14 includes a sun gear 18 disposed at the center, a ring gear 20 disposed concentrically with the sun gear 18 and having inner teeth on the inner periphery of the annular ring, and a plurality of gears meshing with both the sun gear 18 and the ring gear 20. And a planetary gear mechanism including a planetary gear 22. The plurality of planetary gears 22 are rotatably attached to end portions of the carrier 26, respectively.

  In the power split mechanism 14, the output shaft 13 of the engine 12 is connected to the carrier 26 via a damper 24 for reducing torque impact, and the rotary shaft 30 connected to the rotor 29 of the motor MG 1 is connected to the sun gear 18. A reduction gear 34 is connected to the ring gear 20 via a ring gear shaft 32. Thus, in power split mechanism 14, when motor MG1 functions as a generator, power from engine 12 input from carrier 26 is distributed to sun gear 18 side and ring gear 20 side according to the gear ratio, and motor MG1. When the motor functions as an electric motor, the power of the engine 12 input from the carrier 26 and the power from the MG 1 input from the sun gear 18 are integrated, and the speed reducer includes a gear train having a predetermined reduction ratio from the ring gear 20 via the ring gear shaft 32. 34 is configured to be input.

  A rotary shaft 38 connected to the rotor 36 of the motor MG2 is also connected to the speed reducer 34. When the motor MG2 functions as an electric motor, power from the motor MG2 is input to the speed reducer 34.

  The power input from at least one of the ring gear shaft 32 and the rotation shaft 38 of the motor MG2 is transmitted to the axle 40 through the speed reducer 34, whereby the wheels 42 are rotationally driven. On the other hand, when power is input from the wheel 42 and the axle 40 to the rotary shaft 38 via the speed reducer 34 during regenerative braking, the motor MG2 functions as a generator. Here, during regenerative braking, not only when the driver brakes the vehicle to reduce the vehicle speed, but also when the driver releases the accelerator pedal and stops vehicle acceleration, or when the vehicle goes downhill. This includes cases where the vehicle is traveling by gravity.

  Motors MG1 and MG2 are electrically connected to corresponding inverters 44 and 46, respectively. Each inverter 44 and 46 is connected to a battery 50 as a DC power source via a DC / DC converter (hereinafter simply referred to as a converter) 48. Electrically connected. As the battery 50, a secondary battery such as a lithium ion battery is preferably used. However, instead of the battery, an electric double layer capacitor, a fuel cell that generates power using hydrogen as a fuel, or the like may be used as the DC power source.

  When motors MG1 and MG2 function as an electric motor, converter 48 is supplied with DC voltage Vb, which is a battery voltage, from battery 50 via smoothing capacitor 52. The converter 48 has a function of boosting the input voltage Vb to a predetermined value Vc and outputting it. Converter 48 generally includes, but is not limited to, one reactor, two power switching elements (eg, IGBT) and two diodes connected in anti-parallel to these switching elements. Instead, a converter having any configuration having a DC voltage step-up / step-down function may be used.

  The converter 48 is electrically connected to a motor ECU (hereinafter referred to as a motor ECU) 60, which will be described later, and an on / off control signal for each switching element transmitted from a hybrid ECU (control device) described later. The operation is controlled based on this, and the battery voltage Vb can be raised to a predetermined voltage value Vc, or the regenerative power can be lowered to a voltage that can charge the battery 50.

  The DC voltage Vc output from the converter 48 is input to the inverters 44 and 46 via the smoothing capacitor 54. Each inverter 44, 46 converts the input DC voltage Vc into a three-phase AC voltage and applies it to the motors MG1, MG2, thereby rotating the motors MG1, MG2 as electric motors. As described above, the converter output voltage Vc is an inverter input voltage, which is hereinafter referred to as a system voltage VH.

  Each of the inverters 44 and 46 includes a U-phase arm, a V-phase arm, and a W-phase arm that are configured by connecting in series two power switching elements (for example, IGBTs) each having a diode connected in antiparallel. The intermediate points of the U-phase, V-phase, and W-phase arms are connected to the phase coils of the motors MG1 and MG2, respectively. However, the inverter is not limited to the configuration described above, and any configuration having a DC / AC conversion function may be used.

  Since the motor MG1 is connected to the engine 12 via the power split mechanism 14, the motor MG1 can be used as a cell motor when the engine is started by being driven as an electric motor. Further, the motor MG1 is driven as an electric motor for torque control. Thus, it can also be used as a transmission for shifting the rotational speed Ne of the engine 12.

  On the other hand, when the motors MG1 and MG2 function as generators, the three-phase AC voltage output from the motors MG1 and MG2 is converted into DC by the inverters 44 and 46, and then the voltage is stepped down by the converter 48 to charge the battery 50. Further, since the inverters 44 and 46 share the power lines 56 and 58 connected to the converter 48, the power generated by one of the motors MG 1 and MG 2 is not transmitted through the converter 48 and the other motor. And can be driven to rotate.

  The inverters 44 and 46 are electrically connected to a motor ECU (hereinafter referred to as a motor ECU) 60, and their operations are controlled based on an on / off control signal of a power switching element transmitted from the motor ECU 60. . The motors MG1 and MG2 are provided with rotation angle sensors 31 and 37 for detecting the rotation angles of the rotors 29 and 36, respectively. The rotation angle sensors 31 and 37 are preferably configured by, for example, a resolver. The detection values by the rotation angle sensors 31 and 37 are input to the motor ECU 60 and used for calculating the motor rotation speeds Nm1 and Nm2. The motor ECU 60 corresponds to the control device in the present invention.

  Motor ECU 60 includes converter 48 and inverters 44 and 46 to output power required from motor MG1 and / or MG2 based on torque command Tmg * input from hybrid ECU 66 (hereinafter referred to as hybrid ECU) described later. Control the behavior. When motor ECU 60 receives the regeneration command from hybrid ECU 66, motor ECU 60 controls converter 48 and inverter 46 to charge battery 50 with the generated power output from motor MG2.

  The battery 50 is provided with an SOC sensor 62 for detecting a state of charge (SOC). The SOC sensor 62 can be configured by a current sensor that detects a charge / discharge current of the battery 50. The value detected by the SOC sensor 62 is input to a battery ECU (hereinafter referred to as “battery ECU”) 64. The battery ECU 64 is input with a battery voltage Vb detected by a voltage sensor, a battery temperature detected by a temperature sensor (not shown), and the like. The battery ECU 64 monitors and controls the battery remaining capacity SOC based on the integrated value of the charge / discharge current detected by the SOC sensor 62 so that the remaining battery capacity SOC is maintained in an appropriate range. Or a discharge restriction signal is output to the hybrid ECU 66.

  The hybrid ECU 66 is electrically connected to the engine ECU 16, the motor ECU 60, and the battery ECU 64, respectively, and has a function of comprehensively controlling the engine 12 and the motors MG1 and MG2 and managing the battery 50. The hybrid ECU 66 includes a CPU (or MPU) that executes various programs for vehicle control, a ROM that stores a control program, a control map, and the like in advance, a RAM that can store and read various detection values as needed, and the like. It can be suitably configured.

  The hybrid ECU 66 transmits an engine control signal to and from the engine ECU 16 as necessary, and receives data relating to the engine operating state (for example, engine speed Ne) as necessary. The hybrid ECU 66 transmits a required torque command Tmg * to the motor ECU 60 as necessary, and receives data relating to the motor operating state (for example, motor rotation speeds Nmg1, Nmg2, motor current, etc.) as necessary. To do. Further, the hybrid ECU 66 receives data necessary for battery management such as the remaining battery capacity SOC, battery voltage, battery temperature, and charge / discharge restriction signal from the battery ECU 64.

  A vehicle speed sensor 68 and an accelerator opening sensor 70 are electrically connected to the hybrid ECU 66, and a vehicle speed Sv that is the traveling speed of the hybrid vehicle 1 and an accelerator opening Ac that corresponds to a depression amount of an accelerator pedal (not shown). Are entered respectively.

  The hybrid ECU 66 is electrically connected to a navigation device 71 installed in a place where the driver can easily see. The navigation device 71 has a function of searching and setting a route to the destination in accordance with a destination setting operation by a driver or the like. Furthermore, the navigation device 71 also has a function of acquiring traffic jam information and the like of the scheduled road through communication with the outside of the vehicle.

  Next, referring to flowcharts shown in FIGS. 2 and 3, the setting of the boosted voltage of converter 48, that is, system voltage VH by drive control system 10 according to the embodiment of the present invention will be described.

  First, in the memory in the motor ECU 60, two maps created in advance are stored. One of these maps is a map created based on the operating state (rotation speed and torque) of the motors MG1 and MG2 when the hybrid vehicle 1 travels in a predetermined travel pattern. That's it. Another map is a map that prescribes the operating states (rotation speed and torque) of the motors MG1 and MG2 mainly from the viewpoint of improving the controllability (or control responsiveness) of the motors MG1 and MG2. This is called a controllability map. The motor ECU 60 can generate torque command values Tmg1 * and Tmg2 * for the motors MG1 and MG2 with reference to the travel pattern map or controllability map as appropriate.

  Here, as the predetermined traveling pattern, a typical traveling pattern set in advance is exemplified. The typical running pattern is, for example, a test mode (for example, 10.15 mode) defined in the exhaust gas test method, but is not limited thereto.

  The traveling state of the hybrid vehicle 1 is always stored in the hybrid ECU 66, and the traveling pattern map may be updated based on the traveling pattern set from the past traveling history. For example, when the hybrid vehicle 1 is a private vehicle used exclusively for commuting, or a business vehicle that travels on a fixed route, the traveling pattern becomes almost constant, and the traveling pattern map is updated accordingly. As a result, the efficiency of the entire system can be improved and the fuel efficiency can be improved more effectively.

  Alternatively, when the destination and route are set by the navigation device 71 by the operation of the driver or the like, the distance to the destination, the position of the intersection in the route, the presence or absence of traffic lights, the position of the uphill and downhill roads, A traveling pattern may be estimated in consideration of the number, the inclination, etc., and a new traveling pattern map may be created based on the estimated traveling pattern and used for driving control of the motors MG1 and MG2. In this case, the motors MG1 and MG2 are driven and controlled in accordance with a travel pattern map that matches the actual travel pattern to be traveled, so that the efficiency of the entire system can be improved and the fuel efficiency can be improved more effectively.

  Referring to FIG. 2, in step S10, motor ECU 60 refers to the travel pattern map to request output (revolution speed) to motors MG1 and MG2 in accordance with the vehicle state (vehicle speed Sv, accelerator opening degree Ac, etc.). Torque command values Tmg1 * and Tmg2 * are set according to (X torque).

  Further, in step S14, motor ECU 60 calculates motor required voltage Vmg1 in accordance with the induced voltage of motor MG1 in accordance with the rotational speed of motor MG1 and torque command value Tmg1 *. Similarly, in step S12, motor ECU 60 calculates required motor voltage Vmg2 in accordance with the induced voltage of motor MG2 in accordance with the rotational speed of motor MG2 and torque command value Tmg2 *.

  Here, in motors MG1 and MG2, when the rotational speed and / or torque increases, the counter electromotive force increases and the induced voltage increases. Therefore, in steps S14 and S12, required motor voltages Vmg1 and Vmg2 are set to be equal to or higher than the induced voltages of motors MG1 and MG2, respectively.

  That is, motor required voltages Vmg1 and Vmg2 are set to be relatively high according to the torque and rotational speed of motors MG1 and MG2, specifically, in the region of high rotational speed and high torque. For each of the motors MG1 and MG2, the necessary voltage Vmg1 and Vmg2 are calculated in steps S14 and S12 by referring to the travel pattern map reflecting such characteristics with the torque command value Tmg * and the rotation speed Nmg as arguments. it can.

  Subsequently, in step S16, the motor ECU 60 calculates a required minimum voltage VHmin that is the maximum value of the MG1 required voltage Vmg1 and the MG2 required voltage Vmg2 calculated in steps S14 and S12, respectively.

  In step S18, the motor ECU 60 sets a plurality of candidate voltages VH (1) to VH (n) within the voltage range of the maximum output voltage VHmax of the converter 48 from the necessary minimum voltage VHmin obtained in step S16. Here, n is an integer of 2 or more. Then, the variable i = 1 is set as an initial value. Note that the number of candidate voltages VH (1) to VH (n) and / or the voltage interval may be fixed values, or may be variably set according to the operating states of the motors MG1 and MG2. Further, the voltage intervals of the candidate voltages VH (1) to VH (n) are not necessarily limited to equal intervals.

  Subsequently, motor ECU 60 derives power loss (converter loss) LPc in converter 48 at candidate voltage VH (i) in step S20. Here, converter loss LPc is a frequency fcc of a carrier wave (generally a triangular wave, also referred to as a carrier) used to generate a signal for on / off control of a switching element included in converter 48, and a candidate for system voltage. It can be expressed as a function of the voltage VH (i), the battery voltage Vb, and the battery current Ib, that is, LPc (fcc, VH (i), Vb, Ib).

  Further, in step S22, motor ECU 60 derives a sum LPmg1 of power loss at inverter 44 and power loss at motor MG1 (hereinafter referred to as MG1 system loss) at candidate voltage VH (i). Here, MG1 system loss LPmg1 is carrier frequency fc1, system voltage candidate voltage VH (i), torque (or torque command value) used to generate a signal for on / off control of the switching element included in inverter 44. ) Tmg1 and a function of the rotation speed Nmg1, that is, LPmg1 (fc1, VH (i), Tmg1, Nmg1).

  Similarly, motor ECU 60 calculates LPmg2 (hereinafter referred to as MG2 system loss) of the loss power of inverter 46 and the loss power of motor MG2 at candidate voltage VH (i) in step S24. Here, MG2 system loss LPmg1 is carrier frequency fc2, system voltage candidate voltage VH (i), torque (or torque command value) used to generate a signal for on / off control of the switching element included in inverter 46. ) Tmg2 and a function of the rotation speed Nmg2, that is, LPmg2 (fc2, VH (i), Tmg2, Nmg2).

In step S26, the motor ECU 60 adds up the total loss power LPt = Σ (LPc + LPmg1 +) which is the sum of the converter loss LPc, the MG1 system loss LPmg1 and the MG2 system loss LPmg2 derived in steps S20, S22 and S24, respectively.
LPmg2) is calculated. Then, the motor ECU 60 calculates the total loss power LPt in the entire system for each of the candidate voltages VH (1) to VH (n) by the iterative process in steps S28 and S30.

  Subsequently, in step S32, the motor ECU 60 formulates a candidate voltage VH (j) that minimizes the total loss power LPt from among the candidate voltages VH (1) to VH (n). In step S34, the motor ECU 60 calculates the optimum voltage VHopt (first boosted voltage) based on the formulated candidate voltage VH (j). At this time, the candidate voltage VH (j) may be used as the optimum voltage VHopt as it is, or optimal by interpolation between the candidate voltage VH (j) and the adjacent candidate voltage VH (j−1) or VH (j + 1). The voltage VHopt may be calculated.

  Referring to FIG. 3, the motor ECU 60 refers to the controllability map in step S36 in parallel with the above steps S10 to S34, according to the vehicle state (vehicle speed Sv, accelerator opening degree Ac, etc.), Torque command values Tmg1 * and Tmg2 * are set according to the output request (rotation speed × torque) to motors MG1 and MG2.

  Subsequently, the motor ECU 60 calculates the necessary motor voltages Vmg1 and Vmg2 through steps S38 to S42 which are the same processes as the above-described steps 12 to 16, and the necessary minimum voltage which is the maximum value of the necessary motor voltages Vmg1 and Vmg2. VHmin is calculated. In step S44, motor ECU 60 sets required minimum voltage VHmin calculated in motor step S42 as system voltage VHcont (second boosted voltage) required from the controllability of motors MG1 and MG2.

  Referring to FIG. 2 again, in step S46, the motor ECU 60 selects one of the optimum voltage VHopt obtained in step S34 in consideration of the running pattern and the system voltage VHcont required from the controllability obtained in step S44. The larger one is selected and set as the system voltage command value (boost voltage command value) VH *.

  Here, if the optimum voltage VHopt is set as the system voltage command value VH *, the power loss of the entire system can be minimized in consideration of the running pattern while ensuring the controllability of the motors MG1 and MG2. Therefore, it is possible to improve overall system efficiency and improve fuel efficiency. On the other hand, if the system voltage VHcont required from the controllability is set as the system voltage command value VH *, the power loss of the entire system may be somewhat increased, but the control responsiveness is good for the motors MG1 and MG2. Driving is possible, and the user can be satisfied with the controllability or drivability of the vehicle.

  As described above, according to the drive control system 10 of the present embodiment, it is possible to appropriately set the boost voltage of the converter 48 in consideration of both improvement in system efficiency and ensuring of system controllability.

  Although not shown in the flowcharts of FIGS. 2 and 3, when the necessary minimum voltage VHmin obtained in step S16 is equal to the maximum output voltage VHmax of the converter 48, there is no degree of freedom of the system voltage VH. Therefore, the processing of steps S18 to S44 is omitted, and the system voltage command value VH * = VHmax (= VHmin) is set.

  Although the hybrid vehicle drive control system according to one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made.

  For example, in the above embodiment, a plurality of candidate voltages are set only for the system voltage VH, which is the output voltage boosted by the converter 48, and the optimum voltage is calculated based on the candidate voltage with the smallest total power loss. However, a plurality of candidate frequencies are also set for the carrier frequency fcc of the converter 48 and the carrier frequencies of the inverters 44 and 46, and the total loss is obtained for all combinations of the plurality of candidate frequencies and the plurality of candidate voltages. Even if the power LPt is calculated and the optimum voltage VHopt and the optimum frequency fcopt that minimize the total power loss (including the optimum frequencies fccopt, fc1opt, and fc2opt for each carrier frequency of the converter 48 and the inverters 44 and 46) are calculated. Good. As a result, the system efficiency can be improved more precisely by minimizing the power loss in the entire system.

  Further, since the loss in the system differs between the power running of motor MG1 and MG2 and the regeneration, a map (running pattern map and / or controllability map) may be created in consideration of the loss during regeneration.

  Furthermore, in the above embodiment, the system voltage command value is set by comparing the optimum voltage obtained with reference to the travel pattern map and the system voltage obtained with reference to the controllability map. It may be common. For example, using the system voltage obtained by referring to the controllability map of the vehicle, the total loss power of the entire system when the electric vehicle travels in a predetermined travel pattern is calculated, and the optimum voltage that minimizes the total loss power May be determined and set as a system voltage command value.

  DESCRIPTION OF SYMBOLS 1 Hybrid vehicle, 10 Drive control system, 11 Rotation angle sensor, 12 Engine, 13 Output shaft, 14 Power distribution integration mechanism, 16 Engine ECU, 18 Sun gear, 20 Ring gear, 22 Planetary gear, 24 Damper, 26 Carrier, 29, 36 Rotor , 30, 38 Rotating shaft, 31, 37 Rotating angle sensor, 32 Ring gear shaft, 34 Reducer, 40 Axle, 42 Wheel, 44, 46 Inverter, 48 DC / DC converter, 50 Battery, 52, 54 Smoothing capacitor, 56, 58 power line, 60 motor ECU, 62 SOC sensor, 64 battery ECU, 66 hybrid ECU, 68 vehicle speed sensor, 70 accelerator opening sensor, 71 navigation device, MG1, MG2 motor.

Claims (3)

A converter capable of boosting a DC voltage from a DC power supply, an inverter capable of converting a boosted voltage output from the converter into an AC voltage, a rotating electrical machine driven by application of an AC voltage output from the inverter, a converter, and An electric vehicle drive control system comprising a control device for controlling the operation of an inverter,
The controller is
A loss power deriving unit for deriving a total loss power of the loss power in the converter, the loss power in the inverter, and the loss power in the rotating electrical machine when the electric vehicle travels in a predetermined travel pattern;
A first boosted voltage deriving unit for deriving a first boosted voltage that minimizes the total loss power;
A second boosted voltage deriving unit for deriving a second boosted voltage required from the controllability of the rotating electrical machine;
A boost voltage setting unit for setting a boost voltage command value by the converter based on the first and second boost voltages;
A drive control system for an electric vehicle. The drive control system for an electric vehicle according to claim 1,
The first boost voltage deriving unit obtains a value that minimizes the total loss power even for a carrier frequency that is one of the parameters used to obtain the first boost voltage that minimizes the total loss power. A drive control system for an electric vehicle. The drive control system for an electric vehicle according to claim 1 or 2,
The predetermined travel pattern is any one of a typical travel pattern set in advance, a travel pattern set from a past travel history, and a travel pattern set via an in-vehicle navigation device. A drive control system for an electric vehicle.

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