JP2012192769A - Electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a secondary batteries and a boost converter.SOLUTION: A temporary output limit Wtmp1 is set based on a battery temperature Tb and a remaining capacity SOC of a battery (S110), and a temporary output limit Wtmp2 is set to obtain predetermined power Wref when a refrigerant temperature Tw is not higher than a predetermined temperature Tref for the boost converter. When the refrigerant temperature Tw exceeds the predetermined temperature Tref, the temporary output limit Wtmp2 is set so that power becomes smaller than the predetermined power Wref and it becomes smaller as the refrigerant temperature Tw is higher (S120). A smaller value of the temporary output limits Wtmp1 and Wtmp2 is set as an output limit Wout (S130). Two motors, the booster converter and an engine are controlled so that required torque is output from a drive shaft within a range of the set output limit Wout. Thus, the battery and the boost converter can be protected.

Description

  The present invention relates to an electric vehicle, and more specifically, an electric motor that inputs and outputs driving power, a chargeable / dischargeable secondary battery, a battery voltage system to which a secondary battery is connected, and a drive voltage system to which the motor is connected. And a boost converter that boosts the voltage of the drive voltage system to a voltage higher than the voltage of the battery voltage system and transfers power between the drive voltage system and the battery voltage system, and cooling that cools the boost converter using a cooling medium And an electric vehicle including the apparatus.

  Conventionally, as this kind of electric vehicle, a motor that is driven by electric power from a battery is mounted, and a motor that limits the output of the motor based on the battery voltage, the battery temperature, and the temperature of an inverter that drives the motor has been proposed. (For example, refer to Patent Document 1). In this electric vehicle, when the output of the motor is restricted and then the restriction is relaxed, the time change of the restriction is restricted within a predetermined value, so that the same accelerator opening is set before and after the motor output restriction is relaxed. It is possible to suppress rapid acceleration.

JP-A-9-191582

  In general, in an electric vehicle including a boost converter that boosts power from a secondary battery and supplies it to an electric motor, it is important to protect the boost converter by suppressing overheating of the boost converter as well as protecting the secondary battery. It is considered as one of As a method of suppressing such overheating of the boost converter, a method of cooling the boost converter using cooling water is conceivable. However, when the temperature of the cooling water is relatively high, the cooling performance is deteriorated, so that the boost converter is likely to be overheated. End up.

  The main object of the electric vehicle of the present invention is to protect the secondary battery and to protect the boost converter.

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

The electric vehicle of the present invention is
The drive voltage system connected to an electric motor that inputs and outputs driving power, a rechargeable secondary battery, a battery voltage system to which the secondary battery is connected, and a drive voltage system to which the electric motor is connected A boost converter that boosts the voltage of the battery voltage system to a voltage higher than the voltage of the battery voltage system and transfers power between the drive voltage system and the battery voltage system; and a cooling device that cools the boost converter using a cooling medium. An electric vehicle comprising:
Battery temperature detection means for detecting the temperature of the secondary battery;
Refrigerant temperature detecting means for detecting the temperature of the cooling medium;
A first temporary output limit is set based on a capacity ratio that is a ratio of a capacity stored in the secondary battery to a maximum capacity that can be stored in the secondary battery, and a detected temperature of the secondary battery. 1 temporary output limit setting means;
Second provisional output restriction setting means for setting a second provisional output restriction so that the temperature of the detected cooling medium becomes higher as the temperature of the cooling medium becomes higher;
An output limit that sets a smaller value of the set first temporary output limit and the set second temporary output limit to an output limit that is a maximum value of power allowed to be output to the secondary battery. Setting means;
Control means for controlling the electric motor and the step-up converter so as to run at a required torque required for running within the set output limit range;
It is a summary to provide.

  In the electric vehicle of the present invention, the first temporary output is based on the capacity ratio that is the ratio of the capacity stored in the secondary battery to the maximum capacity that the secondary battery can store, and the detected temperature of the secondary battery. A limit is set, the second temporary output limit is set such that the detected temperature becomes lower as the temperature of the cooling medium increases, and the smaller of the set first temporary output limit and the set second temporary output limit Is set to an output limit that is the maximum power that can be output by the secondary battery, and the motor is configured to output torque based on the required torque required for traveling within the set output limit range. Controls the boost converter. The smaller value of the first temporary output limit and the second temporary output limit is set as the output limit, and torque based on the required torque required for traveling within the set output limit range is output from the motor. Since the electric motor and the boost converter are controlled, the secondary battery can be protected. Further, the higher the temperature of the cooling medium, the lower the cooling performance when the boost converter is cooled by the cooling medium, and the boost converter is likely to overheat, but the smaller of the first temporary output limit and the second temporary output limit. Is set as the output limit, and the temperature of the cooling medium is controlled by controlling the motor and the boost converter so that torque based on the required torque required for running within the set output limit range is output from the motor. The higher the value, the smaller the output limit, so that the torque to be output from the motor is reduced and the power consumed by the boost converter is reduced. Thereby, overheating of the boost converter can be suppressed and the boost converter can be protected. As a result, the secondary battery can be protected and the boost converter can be protected.

  In such an electric vehicle according to the present invention, the second temporary output restriction setting means is preset when the detected temperature of the cooling medium is equal to or lower than a predetermined temperature that is predetermined as an upper limit of a temperature at which the boost converter can be satisfactorily cooled. The predetermined predetermined power is set to the second temporary output limit, and when the detected temperature of the cooling medium is higher than the predetermined temperature, the predetermined electric power is smaller than the predetermined electric power and becomes smaller as the detected temperature of the cooling medium is higher. It can also be a means for setting the tendency power to the second temporary output limit. In this way, it is possible to more appropriately set the output limit and more appropriately suppress overheating of the boost converter.

  In the electric vehicle of the present invention, an internal combustion engine that outputs power, a generator that can input and output power, an output shaft of the internal combustion engine, a drive shaft that is connected to an axle, and a rotary shaft of the generator Three-axis type power input / output means connected to three axes and inputting / outputting power to / from the remaining shaft based on power input / output to / from any two of the three axes, Is connected to the drive shaft, the generator is connected to the drive voltage system, and the control means travels with the required torque within the set output limit range. And the means for controlling the generator, the electric motor, and the step-up converter. In this way, overheating of the boost converter can be more appropriately suppressed even in an electric vehicle including an internal combustion engine, a generator, and a three-axis power input / output unit.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is a block diagram which shows the outline of a structure of the electric drive system containing motor MG1, MG2. 4 is a flowchart illustrating an example of an output limit setting process routine executed by a battery ECU 52. It is explanatory drawing which shows an example of the relationship between battery temperature Tb and temporary output restrictions Wtmp1. It is explanatory drawing which shows an example of the relationship between the remaining capacity SOC of the battery 50, and the correction coefficient of temporary output restriction | limiting Wtmp. It is explanatory drawing which shows an example of the relationship between refrigerant | coolant temperature Tw and temporary output restriction | limiting Wtmp2. 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 the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22 that uses gasoline or light oil as fuel, an engine electronic control unit (hereinafter referred to as engine ECU) 24 that controls the drive of the engine 22, and a crank of the engine 22. A planetary gear 30 in which a carrier is connected to the shaft 26 and a ring gear is connected to a drive shaft 32 connected to the drive wheels 33a and 33b via a differential gear 34, and a rotor is configured as a synchronous generator motor, for example. A motor MG1 connected to the sun gear, a motor MG2 configured as a synchronous generator motor and having a rotor connected to the drive shaft 32, inverters 41 and 42 for driving the motors MG1 and MG2, and inverters 41, 42 is controlled by switching control. A motor electronic control unit (hereinafter referred to as a motor ECU) 40 for driving and controlling the motors MG1 and MG2, a battery 50 configured as, for example, a lithium ion secondary battery, and a battery electronic control unit (hereinafter referred to as a battery control unit) that manages the battery 50 Connected to a power line (hereinafter referred to as drive system power line) 54a to which inverters 41 and 42 are connected, and a power line (hereinafter referred to as battery voltage system power line) 54b to which battery 50 is connected. Then, the voltage VH of the drive system power line 54a is adjusted within the range of the voltage VL of the battery voltage system power line 54b to the maximum allowable voltage VHmax, and the electric power between the drive system power line 54a and the battery voltage system power line 54b is adjusted. Boost converter 55 that performs exchange, inverters 41 and 42, and boost converter Includes a cooling system 60 for cooling the over data 55, the hybrid electronic control unit 70 for controlling the entire vehicle, a. Here, the maximum allowable voltage VHmax may be a value slightly lower than the breakdown voltage of the capacitor 57 described later.

  Each of the motor MG1 and the motor MG2 is configured as a known synchronous generator motor including a rotor in which a permanent magnet is embedded and a stator around which a three-phase coil is wound. As shown in the block diagram of the electric drive system including the motors MG1 and MG2 in FIG. 2, the inverters 41 and 42 are in reverse directions to the six transistors T11 to T16 and T21 to 26 and the transistors T11 to T16 and T21 to T26. 6 diodes D11 to D16, D21 to D26 connected in parallel. Two transistors T11 to T16 and T21 to T26 are arranged in pairs so as to be on the source side and the sink side with respect to the positive and negative buses of the drive system power line 54a, respectively. Each of the three-phase coils (U-phase, V-phase, W-phase) of motors MG1, MG2 is connected to each connection point. Therefore, the three-phase coil is controlled by controlling the on-time ratios of the transistors T11 to T16 and T21 to T26 that make a pair in a state where a voltage is applied between the positive and negative buses of the drive system power line 54a. A rotating magnetic field can be formed, and the motors MG1 and MG2 can be driven to rotate. Since the inverters 41 and 42 share the positive and negative buses of the drive system power line 54a, the power generated by one of the motors MG1 and MG2 can be supplied to another motor. A smoothing capacitor 57 is connected to the positive and negative buses of the drive system power line 54a.

  The motor ECU 40 is configured as a microprocessor centered on a CPU (not shown), and includes a ROM, a RAM, 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, the rotational positions of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2. The rotational position, the phase current applied to the motors MG1 and MG2 detected by a current sensor (not shown), the inverter temperature from a temperature sensor (not shown) attached to the inverters 41 and 42, and the like are input. Switching control signals to the transistors T11 to T16 and T21 to 26 of the inverters 41 and 42 are output. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44.

  As shown in FIG. 2, the boost converter 55 is configured as a boost converter including two transistors T31 and T32, two diodes D31 and D32 connected in parallel to the transistors T31 and T32 in a reverse direction, and a reactor L. . The two transistors T31 and T32 are connected to the positive bus of the drive system power line 54a and the negative bus of the drive system power line 54a and the battery voltage system power line 54b, respectively, and the reactor L is connected to the connection point. Yes. Further, the positive terminal and the negative terminal of battery 50 are connected to reactor L and negative buses of drive system power line 54a and battery voltage system power line 54b, respectively. Therefore, by turning on / off the transistors T31 and T32, the power of the battery voltage system power line 54b is boosted and supplied to the drive system power line 54a, or the power of the drive system power line 54a is reduced to reduce the battery voltage system power. Or can be supplied to the line 54b. A smoothing capacitor 58 is connected to the reactor L and the negative bus of the drive system power line 54a and the battery voltage system power line 54b.

  The cooling system 60 circulates a cooling medium 61 such as water, a pump 62 for circulating the cooling medium in the circulation path 61, and the cooling medium 60 is cooled by the outside air incorporated in the circulation path 61. A heat exchanger 63, a heat exchanging unit 64 that is incorporated in the circulation channel 61 and attached to the bases of the inverters 41 and 42 and the boost converter 55 and cools the inverters 41 and 42 and the boost converter 55 by a cooling medium by heat transfer; Is provided. The pump 62 of the cooling system 60 is connected to the hybrid electronic control unit 70 through a signal line, and is driven and controlled by the hybrid electronic control unit 70.

  The battery ECU 52 is configured as a microprocessor centered on a CPU (not shown), and includes a ROM, a RAM, an input / output port, and a communication port in addition to the CPU. In the battery ECU 52, signals necessary for managing the battery 50, for example, voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, battery voltage system power connected to the output terminal of the battery 50 The charging / discharging current from a current sensor (not shown) attached to the line 54b, the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input, and data regarding the state of the battery 50 is communicated as necessary. Output to the hybrid electronic control unit 70. Further, the battery ECU 52 determines the remaining capacity SOC, which is a ratio of the currently stored capacity to the maximum capacity that the battery 50 can store based on the integrated value of the charge / discharge current detected by the current sensor to manage the battery 50. , Calculating the input limit Win that is the maximum allowable power that may be charged to the battery 50 based on the calculated remaining capacity SOC and the battery temperature Tb, or charging the battery 50 by the output limit setting process described later The output limit Wout, which is the maximum allowable power, may be calculated. The input limit Win of the battery 50 sets a basic value of the input limit Win based on the battery temperature Tb, sets an input limit correction coefficient based on the remaining capacity SOC of the battery 50, and sets the set input limit Win. Can be set by multiplying the basic value by a correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. In the hybrid electronic control unit 70, the voltage of the capacitor 57 (voltage of the drive system power line 54 a) VH from the voltage sensor 57 a attached between the terminals of the capacitor 57 and the voltage sensor 58 a attached between the terminals of the capacitor 58. The voltage of the capacitor 58 (voltage of the battery voltage system power line 54b) VL, the refrigerant temperature Tw from the temperature sensor 65 which is attached to the circulation flow path of the cooling system 60 and detects the temperature of the cooling medium, and the ignition from the ignition switch 80 Signal, shift position SP from the shift position sensor 82 that detects the operation position of the shift lever, accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal, and brake pedal that detects the depression amount of the brake pedal Positive A brake pedal position BP from Yonsensa 86, a vehicle speed V from a vehicle speed sensor 88 is input through the input port. From the hybrid electronic control unit 70, switching control signals to the transistors T31 and T32 of the boost converter 55 are output via an output port. As described above, the hybrid electronic control unit 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. ing.

  The hybrid vehicle 20 of the embodiment configured in this way is driven and controlled by a drive control routine (not shown). As the drive control, the hybrid electronic control unit 70 sets a required torque Tr * to be output to the drive shaft 32 based on the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88. The required power Trd required for traveling is multiplied by the set required torque Tr * and the rotational speed Nr of the drive shaft 32 (for example, the rotational speed obtained by multiplying the rotational speed Nm2 of the motor MG2 or the vehicle speed V by a conversion factor). The engine 22 is calculated by subtracting the charge / discharge required power Pb * of the battery 50 obtained based on the remaining capacity SOC of the battery 50 (a positive value when discharged from the battery 50) from the calculated traveling power Pdrv *. The required power Pe * is set as the power to be output from the engine 22, and the required power Pe * is efficiently output from the engine 22. The target rotational speed Ne * and the target torque Te * of the engine 22 are set 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. A torque command Tm1 * as a torque to be output from the motor MG1 is set by the rotational speed feedback control for rotating the engine 22 at the target rotational speed Ne * within the range of the input / output limits Win, Wout, and the motor MG1 is torqued. The torque applied to the drive shaft 32 via the planetary gear 30 when driven by the command Tm1 * is subtracted from the required torque Tr * to set the torque command Tm2 * of the motor MG2, and the set torque command Tm1 * and the rotation speed Nm1 The required voltage and the torque command Tm2 * set to drive the motor MG1 at the operating point consisting of The larger voltage required for driving the motor MG2 at the operating point consisting of the rotational speed Nm2 is set as the target voltage VH * so that the voltage VH of the drive system power line 54a becomes the target voltage VH *. The transistors T31 and T32 of the boost converter 55 are subjected to switching control, and the target rotational speed Ne * and the target torque Te * are transmitted to the engine ECU 24, and the torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * then controls the intake air amount and the fuel injection control in the engine 22 so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *. Perform ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * performs switching control of the transistors T11 to T16 and T21 to T26 of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. Do.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the setting of the output limit Wout of the battery 50 will be described. FIG. 3 is a flowchart illustrating an example of an output limit setting process routine executed by the battery ECU 52. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the output restriction setting processing routine is executed, the battery ECU 52 first inputs data necessary for processing such as the refrigerant temperature Tw (step S100). Here, as the refrigerant temperature Tw, the refrigerant temperature Tw detected by the temperature sensor 65 is inputted from the hybrid electronic control unit 70 by communication.

  When the data is input in this way, a temporary output limit Wout that is the maximum allowable power that may discharge the battery 50 using the battery temperature Tb from the temperature sensor 51 that detects the temperature of the battery 50 and the calculated remaining capacity SOC. The temporary output limit Wtmp1 is set as a value (step S110). Here, the temporary output limit Wtmp1 sets a basic value of the temporary output limit Wtmp1 based on the battery temperature Tb, sets an output limit correction coefficient based on the remaining capacity SOC of the battery 50, and sets the set temporary output limit Wtmp1. Can be set by multiplying the basic value by a correction coefficient. FIG. 4 shows an example of the relationship between the battery temperature Tb and the temporary output limit Wtmp1, and FIG. 5 shows an example of the relationship between the remaining capacity SOC of the battery 50 and the correction coefficient of the temporary output limit Wtmp.

  Subsequently, a temporary output limit Wtmp2 that is a temporary value of the output limit Wout that is the maximum allowable power that may discharge the battery 50 using the input refrigerant temperature Tw is set (step S120). FIG. 6 shows an example of the relationship between the refrigerant temperature Tw and the temporary output limit Wtmp2. As shown in the figure, the temporary output limit Wtmp2 is set to be a predetermined power Wref when the refrigerant temperature Tw is equal to or lower than a predetermined temperature Tref determined as an upper limit of the temperature at which the boost converter 55 can be satisfactorily cooled. The predetermined temperature Tref is set to be smaller than the predetermined power Wref and smaller as the refrigerant temperature Tw is higher. By setting the refrigerant temperature Tw to be the predetermined power Wref when the refrigerant temperature Tw is equal to or lower than the predetermined temperature Tref, the output limit Wout is set to be small when the refrigerant temperature Tw is a temperature at which the boost converter 55 can be cooled satisfactorily. Can be suppressed. Further, the higher the refrigerant temperature Tw, the lower the cooling performance when the boost converter 55 is cooled by the cooling medium and the boost converter 55 is likely to overheat. Therefore, the output limit Wout is reduced to limit the output from the battery 50. Since it is considered to be good, when the refrigerant temperature Tw exceeds the predetermined temperature Tref, the temporary output limit Wtmp2 is set to be smaller than the predetermined power Wref and smaller as the refrigerant temperature Tw is higher, thereby setting the output limit Wout smaller. be able to.

  When the temporary output limits Wtmp1, Wtmp2 are set in this way, the smaller value of the temporary output limits Wtmp1, Wtmp2 is set as the output limit Wout (step S130), and this routine is terminated. When the output limit Wout is set in this way, a torque command Tm1 * as a torque to be output from the motor MG1 is set and the motor MG1 is set within the range of the input / output limits Win and Wout of the battery 50 by the drive control described above. The torque command Tm2 * of the motor MG2 is set by subtracting the torque acting on the drive shaft 32 via the planetary gear 30 when driven by the torque command Tm1 * from the required torque Tr *, and the motors MG1 and MG2 are controlled and set The voltage required to drive the motor MG1 at the operating point consisting of the torque command Tm1 * and the rotational speed Nm1, and the voltage required to drive the motor MG2 at the operating point consisting of the set torque command Tm2 * and the rotational speed Nm2. The larger voltage is set as the target voltage VH *, and the voltage VH of the drive system power line 54a is the target voltage VH *. Transistors T31 of the boost converter 55 so that a voltage VH *, T32 switching control. In other words, the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set to decrease as the output limit Wout decreases, and the target voltage VH * of the drive system power line 54a is set to decrease. The power consumption in the converter 55 is reduced. The higher the refrigerant temperature Tw, the lower the cooling performance when the boost converter 55 is cooled by the cooling medium, and the boost converter 55 becomes overheated. However, when the refrigerant temperature Tw exceeds the predetermined temperature Tref, the temporary output limit Wtmp2 is predetermined. By setting it to be smaller as the refrigerant temperature Tw is lower than the electric power Wref, the power consumption of the boost converter 55 can be further reduced, and overheating of the boost converter 55 can be suppressed. Further, the battery 50 can be protected by setting the smaller value of the temporary output limits Wtmp1, Wtmp2 to the output limit Wout. Therefore, the battery 50 and the boost converter 55 can be protected by such control.

  In the hybrid vehicle 20 of the embodiment described above, the temporary output limit Wtmp1 is set based on the battery temperature Tb and the remaining capacity SOC of the battery 50. When the refrigerant temperature Tw is equal to or lower than the predetermined temperature Tref, the predetermined electric power is set. The temporary output limit Wtmp2 is set so as to be Wref, and when the refrigerant temperature Tw exceeds the predetermined temperature Tref, the temporary output limit Wtmp2 is set to be smaller than the predetermined power Wref and smaller as the refrigerant temperature Tw is higher. , Wtmp2, the smaller value is set as the output limit Wout, and the engine 22, the motors MG1, MG2, and the boost converter 55 are set so that the required torque Tr * is output from the drive shaft 32 within the set output limit Wout. 50 battery protection by controlling It can be protected boost converter 55 there is ensured.

  In the hybrid vehicle 20 of the embodiment, the temporary output limit Wtmp2 is set to be the predetermined power Wref when the refrigerant temperature Tw is equal to or lower than the predetermined temperature Tref as shown in FIG. 6, and the refrigerant temperature Tw exceeds the predetermined temperature Tref. In some cases, the power is set to be smaller as the refrigerant temperature Tw is lower than the predetermined power Wref, but the temporary output limit Wtmp2 may be set to be smaller as the refrigerant temperature Tw is higher. The temporary output limit Wtmp2 may be set so as to gradually decrease as it increases.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is output to the drive shaft 32. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. 7, the drive shaft 32 is connected to the power of the motor MG2. It may be connected to an axle (an axle connected to the wheels 24a and 24b in FIG. 7) different from the other axle (the axle to which the drive wheels 33a and 33b are connected).

  In the hybrid vehicle 20 of the embodiment, the power from the engine 22 is output to the drive shaft 32 connected to the drive wheels 33a and 33b via the planetary gear 30, and the power from the motor MG2 is output to the drive shaft 32. However, as illustrated in the hybrid vehicle 220 of the modified example of FIG. 8, a motor MG is attached to a drive shaft connected to the drive wheels 33a and 33b via a transmission 230, and a rotation shaft of the motor MG is connected to a rotation shaft via a clutch 229. The engine 22 is connected, and the power from the engine 22 is output to the drive shaft via the rotating shaft of the motor MG and the transmission 230, and the power from the motor MG is output to the drive shaft via the transmission 230. It is good also as what to do. Further, as exemplified in the hybrid vehicle 320 of the modification of FIG. 9, the power from the engine 22 is output to the axle connected to the drive wheels 33a and 33b via the transmission 330 and the power from the motor MG is driven. It is good also as what outputs to the axle different from the axle connected to wheel 33a, 33b (the axle connected to wheel 34a, 34b in FIG. 6).

  In the embodiment, the present invention is applied to the hybrid vehicle 20 including the engine 22 and the motor MG1 connected to the drive shaft 32 via the planetary gear 30 and the motor MG2 connected to the drive shaft 32. As illustrated in the electric vehicle 420 of the modified example of FIG. 10, the electric vehicle 420 may be applied to a simple electric vehicle including a motor MG that outputs driving power.

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It is good also as forms of vehicles other than motor vehicles, such as a train.

  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 embodiment, the motor MG2 corresponds to a “motor”, the battery 50 corresponds to a “secondary battery”, the boost converter 55 corresponds to a “boost converter”, the cooling system 60 corresponds to a “cooling device”, The temperature sensor 51 corresponds to the “battery temperature detecting means”, the temperature sensor 65 corresponds to the “refrigerant temperature detecting means”, and the temporary output limit Wtmp1 is set based on the battery temperature Tb and the remaining capacity SOC. The battery ECU 52 that executes the process of step S110 of the setting process routine corresponds to “first temporary output limit setting means”, and when the refrigerant temperature Tw is equal to or lower than the predetermined temperature Tref, the booster converter 55 sets the predetermined power Wref. At the same time, when the refrigerant temperature Tw exceeds the predetermined temperature Tref, the refrigerant temperature Tw is smaller than the predetermined electric power Wref and becomes smaller as the refrigerant temperature Tw is higher. The battery ECU 52 that executes the process of step S120 of the output limit setting process routine of FIG. 3 corresponds to “second temporary output limit setting means”, and outputs the smaller value of the temporary output limits Wtmp1, Wtmp2. The battery ECU 52 that executes the process of step S130 of the output limit setting process routine of FIG. 3 set to Wout corresponds to “output limit setting means”, and sets the torque command Tm2 * of the motor MG2 within the range of the output limit Wout. The target voltage VH * of the voltage VH of the drive system power line 54a is set so that the process transmitted to the motor ECU 40 and the motor MG2 is driven by the torque command Tm2 *, and the voltage VH of the drive system power line 54a becomes the target voltage VH *. Hybrid that controls switching of transistors T31 and T32 of boost converter 55 Motor ECU40 for controlling the inverter 41 to the motor MG2 is driven with the torque command Tm2 * and the received de electronic control unit 70 corresponds to a "control unit".

  Here, the “motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any one that inputs and outputs driving power, such as an induction motor. The “secondary battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and may be a chargeable / dischargeable battery such as a nickel hydride secondary battery, a nickel cadmium secondary battery, or a lead storage battery. Any type of secondary battery may be used. The “boost converter” is not limited to the boost converter 55, and is connected to a battery voltage system to which a secondary battery is connected and a drive voltage system to which an electric motor is connected, and the voltage of the drive voltage system is changed to the battery voltage. Any device may be used as long as the voltage is boosted to a voltage higher than the system voltage and power is transferred between the drive voltage system and the battery voltage system. The “cooling device” is not limited to the cooling system 60, and any device that cools the boost converter using a cooling medium may be used. The “battery temperature detection means” is not limited to the temperature sensor 51, and any device that detects the temperature of the secondary battery may be used. The “first temporary output limit setting means” is not limited to the one that sets the temporary output limit Wtmp1 based on the battery temperature Tb and the remaining capacity SOC, but the secondary battery with respect to the maximum capacity that the secondary battery can store. As long as the first temporary output limit is set based on the capacity ratio, which is the ratio of the capacity stored in the battery, and the detected temperature of the secondary battery, it may be anything. As the “second temporary output restriction setting means”, when the refrigerant temperature Tw is equal to or lower than the predetermined temperature Tref, the boost converter 55 is set to have a predetermined power Wref, and when the refrigerant temperature Tw exceeds the predetermined temperature Tref, the predetermined power Wref is set. It is not limited to a value that is smaller and is set to be smaller as the refrigerant temperature Tw is higher, but is such that the provisional output limit Wtmp2 is set so as to gradually decrease as the refrigerant temperature Tw becomes higher. Any setting may be used as long as the second temporary output limit is set so as to decrease as the temperature increases. The “control means” is not limited to the combination of the hybrid electronic control unit 70 and the motor ECU 40, and may be configured by a single electronic control unit. Further, as the “control means”, the torque command Tm2 * of the motor MG2 is set within the range of the output limit Wout, and the target voltage VH of the voltage VH of the drive system power line 54a is set so that the motor MG2 is driven by the torque command Tm2 *. * Is set to control the transistors T31 and T32 of the boost converter 55 so that the voltage VH of the drive system power line 54a becomes the target voltage VH *, and the inverters 41 and 42 so that the motor MG2 is driven by the torque command Tm2 *. It is not limited to the one that controls the motor, and may be any device that controls the motor and the boost converter so as to run with the required torque required for running within the set output limit range. .

  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 electric vehicles.

  20, 120, 220, 320 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 32 drive shaft, 33a, 33b drive wheel, 34a, 34b wheel, 34 differential gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 54a drive system power line, 54b battery voltage system power line, 55 boost converter, 57, 58 capacitor, 57a, 57b voltage sensor, 70 hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 82 shift position sensor, 84 accelerator pedal positive Sensor, 86 brake pedal position sensor, 88 vehicle speed sensor, 229 clutch, 230, 330 transmission, 420 electric vehicle, D11-D16, D21-D26, D31, D32 diode, L reactor, MG, MG1, MG2 motor, T11 T16, T21 to T26, T31, T32 transistors.

Claims (3)

The drive voltage system connected to an electric motor that inputs and outputs driving power, a rechargeable secondary battery, a battery voltage system to which the secondary battery is connected, and a drive voltage system to which the electric motor is connected A boost converter that boosts the voltage of the battery voltage system to a voltage higher than the voltage of the battery voltage system and transfers power between the drive voltage system and the battery voltage system; and a cooling device that cools the boost converter using a cooling medium. An electric vehicle comprising:
Battery temperature detection means for detecting the temperature of the secondary battery;
Refrigerant temperature detecting means for detecting the temperature of the cooling medium;
A first temporary output limit is set based on a capacity ratio that is a ratio of a capacity stored in the secondary battery to a maximum capacity that can be stored in the secondary battery, and a detected temperature of the secondary battery. 1 temporary output limit setting means;
Second provisional output restriction setting means for setting a second provisional output restriction so that the temperature of the detected cooling medium becomes higher as the temperature of the cooling medium becomes higher;
An output limit that sets a smaller value of the set first temporary output limit and the set second temporary output limit to an output limit that is a maximum value of power allowed to be output to the secondary battery. Setting means;
Control means for controlling the electric motor and the boost converter so that torque based on a required torque required for traveling within the set output limit range is output from the electric motor;
An electric vehicle comprising: The electric vehicle according to claim 1,
The second temporary output limit setting means is configured to apply a predetermined power when the detected temperature of the cooling medium is equal to or lower than a predetermined temperature that is predetermined as an upper limit of a temperature that can satisfactorily cool the boost converter. 2 is set to a temporary output limit, and when the detected temperature of the cooling medium is higher than the predetermined temperature, electric power that is smaller than the predetermined electric power and tends to be smaller as the detected temperature of the cooling medium is higher is set to the second temporary output limit. A means to set output limits,
Electric vehicle. The electric vehicle according to claim 1 or 2,
An internal combustion engine that outputs power;
A generator capable of inputting and outputting power;
The remaining power is based on the power input / output to / from any two of the three shafts connected to the three shafts of the output shaft of the internal combustion engine, the drive shaft connected to the axle, and the rotating shaft of the generator. 3-axis power input / output means for input / output to / from the shaft;
With
The electric motor has a rotating shaft connected to the driving shaft,
The generator is connected to the drive voltage system,
The control means is means for controlling the internal combustion engine, the generator, the electric motor, and the boost converter so that torque based on the required torque is output to the drive shaft within the set output limit range. is there,
Electric vehicle.