Electric vehicle control method and electric vehicle control device

Abstract

This electric vehicle control method is for warming an on-board device by using heat generated by a first electric unit and a second electric unit, in an electric vehicle that includes: the first electric unit and the second electric unit which are for generating torque for travelling; and a battery for supplying power to the first electric unit and the second electric unit. In this control method, when warm-up of the on-board device is required while the electric vehicle is traveling, the first electric unit and the second electric unit are boosted, or the d-axis currents of the first electric unit and the second electric unit are increased, to intensify the heat generated by the entirety of the first electric unit and the second electric unit. Additionally, according to the states of the first electric unit and the second electric unit, the d-axis current of one of the first electric unit and the second electric unit is increased more significantly than the d-axis current of the other so as to preferentially cause one of the first electric unit and the second electric unit to generate heat.

Description

Control method for electric vehicle and control device for electric vehicle

[0001] The present invention relates to a control method and a control device for an electric vehicle.

[0002] JP2001-197607A discloses that when the detected temperature of the battery is lower than a predetermined set temperature, a current is passed through the traveling motor to the extent that the traveling motor does not rotate, thereby warming up the battery.

[0003] In recent electric vehicles, heat generated by an electric unit (electric powertrain) consisting of an electric motor and an inverter is used to warm up onboard equipment such as the battery. Warming up of such onboard equipment using an electric unit is typically achieved by passing a d-axis current through the electric motor while the electric vehicle is stopped. This causes the electric unit to generate heat without rotating the motor, facilitating the warming up of the onboard equipment.

[0004] However, there are cases where an electric vehicle starts moving even though the temperature of on-board equipment such as the battery is low enough to require warming up. In such cases, the electric vehicle needs to warm up the on-board equipment while traveling. When warming up the on-board equipment while traveling, the electric vehicle increases the d-axis current relative to the d-axis and q-axis currents that are used by the electric motor to generate the torque required for traveling, thereby increasing the heat generated in the electric unit and thereby facilitating the warming up of the on-board equipment.

[0005] However, if the d-axis current is increased while the electric vehicle is running, the electric unit may become partially or entirely overheated, resulting in a restriction on the power supply to the electric unit. If the power supply to the electric unit is restricted as a result of increasing the d-axis current, the amount of heat generated by the electric unit cannot be increased any further, and the warm-up of the on-board equipment cannot be promoted.

[0006] The present invention aims to provide a control method and control device for an electric vehicle having multiple electric units, which can increase the overall heat generation amount and promote warming up of on-board equipment while preventing each electric unit from overheating.

[0007] One aspect of the present invention is a control method for an electric vehicle having a first electric unit and a second electric unit that generate torque for driving and a battery that supplies power to the first electric unit and the second electric unit, in which on-board equipment is warmed up using heat generated by the first electric unit and the second electric unit. In this control method, when warming up of the on-board equipment is required while the electric vehicle is driving, the d-axis current of the first electric unit, the second electric unit, or the first and second electric units is increased to increase the heat generated by the entire first and second electric units. Then, depending on the state of the first and second electric units, the d-axis current of one of the first and second electric units is made larger than the d-axis current of the other, thereby preferentially generating heat from one of the first and second electric units.

[0008] FIG. 1 is an explanatory diagram showing a schematic configuration of an electric vehicle. FIG. 2 is a circuit diagram showing the configurations of a first electric unit and a second electric unit. FIG. 3 is a block diagram showing the configuration of a controller. FIG. 4 is a block diagram showing the configuration of a current command generation unit. FIG. 5 is a block diagram showing the configuration of a gain setting unit. FIG. 6 is a block diagram showing the configuration of a warm-up current command generation unit. FIG. 7 is a block diagram showing the configuration of a current control unit. FIG. 8 is a block diagram showing the configuration of a PWM control unit. FIG. 9 is a flowchart related to warm-up control during traveling. FIG. 10 is an explanatory diagram showing transitions of operating points of the first electric unit and the second electric unit in a comparative example. FIG. 11 is an explanatory diagram showing transitions of operating points of the first electric unit and the second electric unit in this embodiment. FIG. 12 is a graph schematically showing the operation of warm-up control. FIG. 13 is a block diagram showing the configuration of a gain setting unit 54 according to a first modified example. FIG. 14 is a block diagram showing the configuration of a current command generation unit according to a second modified example. FIG. 15 is a block diagram showing the configuration of a gain correction unit.

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] 1 is an explanatory diagram showing a schematic configuration of an electric vehicle 100. As shown in FIG. 1, the electric vehicle 100 includes a battery 10, a first electric unit 11, a second electric unit 12, and a controller 13.

[0011] The battery 10 is a DC power supply that stores power to be supplied to the first electric unit 11 and the second electric unit 12. The battery 10 is rechargeable and is charged by an external power supply or a power generation device (neither of which are shown). When the first electric unit 11 and the second electric unit 12 generate power (regenerated power) through so-called regenerative control, the battery 10 is also charged by the regenerated power. The battery 10 is, for example, a lithium-ion battery.

[0012] The battery 10 has a reduced output power and a reduced power capacity when it is in a low temperature state. Therefore, when the battery 10 is in a low temperature state and power is to be supplied from the battery 10 to the first electric unit 11 and the second electric unit 12 or when the battery 10 is to be charged, the battery 10 needs to be warmed up. That is, the battery 10 is one of the devices (hereinafter referred to as on-board devices) mounted on the electric vehicle 100 that needs to be warmed up as necessary. In this embodiment, particular reference is made to a situation in which the battery 10 needs to be warmed up while the electric vehicle 100 is traveling.

[0013] The first electric unit 11 and the second electric unit 12 (electric powertrain) are driving sources for the electric vehicle 100. The first electric unit 11 and the second electric unit 12 are driven by electric power supplied from the battery 10. The first electric unit 11 and the second electric unit 12 can be controlled independently, and can generate a torque required for the electric vehicle 100 to travel (hereinafter referred to as a required torque T ｒｅｑ This causes the following phenomenon:

[0014] The torque generated by the first electric unit 11 (hereinafter referred to as the first torque T １The torque from the first electric unit 11 is transmitted to the drive wheels 24 via the reduction gear 21, the differential gear 22, the drive shaft 23, etc., thereby generating a driving force at the drive wheels 17. In this embodiment, for example, the drive wheels 17 are the front wheels of the electric vehicle 100. Therefore, the first electric unit 11, the reduction gear 21, the differential gear 22, the drive shaft 23, etc. configure a front-wheel drive system 31.

[0015] The torque generated by the second electric unit 12 (hereinafter referred to as the second torque T ２ The second electric unit 12, the reduction gear 26, the differential gear 27, the drive shaft 28, and the like are transmitted to the drive wheels 29. As a result, a driving force is generated in the drive wheels 29. In this embodiment, for example, the drive wheels 29 are the rear wheels of the electric vehicle 100. Therefore, the second electric unit 12, the reduction gear 26, the differential gear 27, the drive shaft 28, and the like constitute a rear-wheel drive system 32.

[0016] When the first electric unit 11 is rotated by the drive wheels 24, the first electric unit 11 can recover the kinetic energy of the electric vehicle 100 by converting it into electrical energy (regenerative power) through regenerative control. Similarly, when the second electric unit 12 is rotated by the drive wheels 29, the second electric unit 12 can recover the regenerative power through regenerative control.

[0017] Furthermore, the first electric unit 11 and the second electric unit 12 are configured to be able to exchange heat with on-board equipment that needs to be warmed up as necessary. In this embodiment, the electric vehicle 100 has, for example, a cooling circuit (not shown) that can circulate water or other refrigerant (hereinafter simply referred to as coolant) common to the battery 10, the first electric unit 11, and the second electric unit 12. Therefore, the electric vehicle 100 can transport heat generated in the first electric unit 11 and the second electric unit 12 to the battery 10 via the coolant, thereby warming up the battery 10.

[0018] The controller 13 is a control device that comprehensively controls each part of the electric vehicle 100. The controller 13 is configured, for example, by one or more computers, and is programmed to control the operation of each part at a predetermined control cycle.

[0019] The controller 13 functions as, for example, a BMS (Battery Management System). ＤＣ and the temperature of the battery 10 (hereinafter referred to as the battery temperature T ｂａｔ The controller 13 can appropriately acquire the charge amount (SOC: State of Charge) of the battery 10 by, for example, integrating the charge / discharge current of the battery 10.

[0020] In particular, in this embodiment, the controller 13 controls the battery temperature T ｂａｔ A predetermined lower limit (threshold value) T ｂａｔ－Ｌｌｉｍ Specifically, the controller 13 compares the battery temperature T ｂａｔ is the lower limit T ｂａｔ－Ｌｌｉｍ When it is smaller than (T ｂａｔ <T ｂａｔ－Ｌｌｉｍ ), it is determined that the battery 10 needs to be warmed up. ｂａｔ is the lower limit T ｂａｔ－Ｌｌｉｍ When it is equal to or greater than (T ｂａｔ ≧T ｂａｔ－Ｌｌｉｍ ), the controller 13 determines that warming up of the battery 10 is not necessary.

[0021] The controller 13 issues a warm-up command S ｗａｒｍ In this embodiment, when it is determined that the battery 10 needs to be warmed up, the controller 13 sets a warm-up command S ｗａｒｍ On the other hand, when it is determined that warm-up of the battery 10 is not necessary, the controller 13 sets the warm-up command S ｗａｒｍ is set to "0 (OFF)" which indicates that warm-up control is not required.

[0022] The controller 13 functions as a VCM (Vehicle Control Module). That is, the controller 13 controls the first electric unit 11, the second electric unit 12, etc. based on output signals from an accelerator pedal sensor, a brake pedal sensor, a parking brake switch, a shift position sensor, etc. (none of which are shown). In this way, the controller 13 controls the behavior of the electric vehicle 100. For example, the controller 13 calculates the accelerator operation amount A by referring to a torque map that is determined in advance by experiment, simulation, etc. ｐｏ (not shown) and the like, the required torque T ｒｅｑ Torque command T ＊ Set.

[0023] The controller 13 also outputs a torque command T ＊ at a predetermined distribution ratio to obtain the first torque command T １ ＊ and the second torque command T ２ ＊ As a result, the controller 13 allocates the accelerator operation amount A ｐｏ The required torque T is determined by the following: ｒｅｑ is distributed to the first electric unit 11 (front wheels) and the second electric unit 12 (rear wheels). １ ＊ is the first torque T that the first electric unit 11 should output. １ The second torque command T ２ ＊ is the second torque T that the second electric unit 12 should output. ２ The controller 13 outputs the first torque command T １ ＊ The first electric unit 11 is driven based on the second torque command T ２ ＊ The behavior of the electric vehicle 100 is controlled by driving the second electric unit 12 based on the above.

[0024] The controller 13 outputs a torque command T ＊The controller 13 determines the distribution ratio of the torque command T ＊ The distribution ratio of the first torque command T １ ＊ and the second torque command T ２ ＊ is determined, and at least T １ ＊ ≠T ２ ＊ Let us assume that:

[0025] Furthermore, in this embodiment, S ｗａｒｍ = 1 and the battery 10 needs to be warmed up, the controller 13 adjusts the current flowing to the first electric unit 11, the current flowing to the second electric unit 12, or both of them. ｒｅｑ While maintaining the above, the heat generated by the first electric unit 11, the second electric unit 12, or both of them is increased, thereby accelerating the warm-up of the battery 10. In this manner, the warm-up of the battery 10 using the heat from the first electric unit 11 and the second electric unit 12 is performed not only when the electric vehicle 100 is stopped, but also, as necessary, when the electric vehicle 100 is running.

[0026] Fig. 2 is a circuit diagram showing the configuration of the first electric unit 11 and the second electric unit 12. As shown in Fig. 2, the first electric unit 11 includes a first electric motor 36 and a first inverter 37. The second electric unit 12 includes a second electric motor 38 and a second inverter 39.

[0027] The first electric motor 36 is driven in response to a first torque command T １ ＊ The torque (first torque T １ The first motor 36 is, for example, a motor that generates a U １ Phase, V １ Phase and W １ It is constituted by a three-phase AC synchronous motor having three phase stator windings.

[0028] The first inverter 37 is an inverter that supplies power from the battery 10 to the first electric motor 36. The first inverter 37 is composed of a plurality of switching elements UP-WN. The first inverter 37 converts DC power input from the battery 10 into AC power and supplies it to the first electric unit 11 by switching these switching elements UP-WN on and off.

[0029] The second electric motor 38 is driven in response to a second torque command T ２ ＊ The torque (second torque T ２ The second motor 38 is a motor that generates a U ２ Phase, V ２ Phase and W ２ It is constituted by a three-phase AC synchronous motor having three phase stator windings.

[0030] The second inverter 39 is an inverter that supplies power from the battery 10 to the second electric motor 38. The second inverter 39 is configured by a plurality of switching elements UP-WN, similar to the first inverter 37. The second inverter 39 converts DC power input from the battery 10 into AC power and supplies it to the second electric motor 38 by switching these switching elements UP-WN on and off.

[0031] In this embodiment, for simplicity, there is no substantial difference in the configuration of the first electric unit 11 and the second electric unit 12, and the first electric unit 11 and the second electric unit 12 are assumed to be equivalent in terms of durability, heat capacity, etc.

[0032] In the following, the current supplied from the battery 10 to the first electric unit 11 and the second electric unit 12 is simply referred to as a DC current i ＤＣ And, the direct current i ＤＣ The current flowing through the first electric unit 11 is referred to as the first unit DC current i ｄｃ１ The current flowing through the second electric unit 12 is called the second unit DC current i ｄｃ２ In addition, the first inverter 37 outputs U １ Phase, V １ Phase and W １The current flowing through each phase (phase current) is i Ｕ１ , i Ｖ１ , i Ｗ１ and these are expressed as the first unit phase current i ＵＶＷ１ Similarly, the second inverter 39 outputs U ２ Phase, V ２ Phase and W ２ The current flowing through each phase (phase current) is i Ｕ２ , i Ｖ２ , i Ｗ２ and these are expressed as the second unit phase current i ＵＶＷ２ These are collectively referred to as:

[0033] 2 is a schematic diagram showing the circuit configuration of the first electric unit 11 and the second electric unit 12, and some elements such as smoothing capacitors are omitted.

[0034] 3 is a block diagram showing the configuration of the controller 13. Here, only the portion that functions as a VCM is shown, and illustration and description of other elements are omitted. As shown in FIG. 3, the controller 13 includes a current command generation unit 41, a current control unit 42, a PWM control unit 43, a coordinate conversion unit 44, and a rotation detection unit 45.

[0035] The current command generator 41 generates a first torque command T １ ＊ , DC voltage V ＤＣ , the electrical angular velocity ω of the first electric motor 36 ｅ１ , and the first dq axis current i ｄｑ１ Based on this, the first current command i ｄｑ１ ＊ Generate.

[0036] 1st current command i ｄｑ１ ＊ is a command for the current to be supplied to the first electric unit 11. ｄｑ１ ＊ is the d-axis current i flowing through the first electric motor 36 ｄ１ (hereinafter, the first d-axis current command i ｄ１ ＊ ) and the q-axis current i ｑ１ (hereinafter, the first q-axis current command i ｑ１ ＊It is composed of the following:

[0037] d-axis current i ｄ１ and q-axis current i ｑ１ represents the current component of the first motor 36 in the dq-axis coordinate system that rotates together with the rotor of the first motor 36. The d-axis current i ｄ１ contributes to the increase or decrease of the interlinkage magnetic flux in the first electric motor 36. The q-axis current i ｑ１ is the first torque T output by the first electric motor 36 １ The first dq-axis current i ｄｑ１ is the d-axis current i of the first electric motor 36 ｄ１ and q-axis current i ｑ１ is.

[0038] Further, the current command generating unit 41 generates a second torque command T ２ ＊ , DC voltage V ＤＣ , the electrical angular velocity ω of the second electric motor 38 ｅ２ , and the second dq axis current i ｄｑ２ Based on this, the second current command i ｄｑ２ ＊ Generate.

[0039] Second current command i ｄｑ２ ＊ is a command for the current to be supplied to the second electric unit 12. ｄｑ２ ＊ is the d-axis current i flowing through the second motor 38 ｄ２ (hereinafter, the second d-axis current command i ｄ２ ＊ ) and the q-axis current i ｑ２ (hereinafter, the second q-axis current command i ｑ２ ＊ It is composed of the following:

[0040] d-axis current i ｄ２ and q-axis current i ｑ２ represents the current component of the second motor 38 in the dq-axis coordinate system that rotates together with the rotor of the second motor 38. The d-axis current i ｄ２ contributes to the increase or decrease of the interlinkage magnetic flux in the second motor 38. The q-axis current i ｑ２ is the second torque T output by the second electric motor 38. ２The second dq axis current i ｄｑ２ is the d-axis current i of the second motor 38 ｄ２ and q-axis current i ｑ２ is.

[0041] In this embodiment, the current command generating unit 41 generates the warm-up command S ｗａｒｍ , the temperature of the first inverter 37 (hereinafter referred to as the first inverter temperature θ ＩＮＶ１ ), the temperature of the second inverter 39 (hereinafter referred to as the second inverter temperature θ ＩＮＶ２ ), the temperature of the first electric motor 36 (hereinafter referred to as the first electric motor temperature θ ＭＯＴ１ ), and the temperature of the second motor 38 (hereinafter referred to as the second motor temperature θ ＭＯＴ２ Based on the above, the first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ Adjust.

[0042] Specifically, S ｗａｒｍ = 0 and the battery 10 does not need to be warmed up, the current command generating unit 41 generates a first current command i based on MTPA (Maximum Torque Per Ampere) control. ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ The MTPA control is a control that sets a current value so that a maximum torque can be obtained with a minimum current. In the following, the first current command i based on the MTPA control is ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ are the first MTPA current commands i ｄｑ１－ＭＴＰＡ ＊ and the second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ In addition, the first MTPA current command i ｄｑ１－ＭＴＰＡ ＊ and the second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ When it is not necessary to distinguish between these, they are collectively referred to as the MTPA current command i ｄｑ－ＭＴＰＡ ＊ This is sometimes the case.

[0043] On the other hand, S ｗａｒｍ= 1 and the battery 10 needs to be warmed up, the current command generating unit 41 generates a first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ The first current command for warm-up i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ is the d-axis current i of the first motor 36 in response to a current command based on the MTPA control. ｄ１ , the d-axis current i of the second electric motor 38 ｄ２ , or both of them, thereby actively increasing the heat generated by the first electric unit 11, the second electric unit 12, or both of them. In the following, the first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ , respectively, the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ and the second warm-up current command i ｄｑ２－ｈｅａｔ ＊ In addition, the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ and the second warm-up current command i ｄｑ２－ｈｅａｔ ＊ When it is not necessary to distinguish between these, they are collectively referred to as the warm-up current command i ｄｑ－ｈｅａｔ ＊ This is sometimes the case.

[0044] The first inverter temperature θ ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ is appropriately acquired by temperature sensors 46a, 46b provided in the first inverter 37 and the second inverter 39, respectively. ＭＯＴ１ and second motor temperature θ ＭＯＴ２ is appropriately acquired by temperature sensors 47a, 47b provided in the first electric motor 36 and the second electric motor 38, respectively. ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ is, for example, the maximum temperature of each of the switching elements UP to WN. ＭＯＴ１ and second motor temperature θ ＭＯＴ２is, for example, the temperature of the stator of the first electric motor 36 and the second electric motor 38.

[0045] The current control unit 42 outputs a first current command i ｄｑ１ ＊ , the electrical angular velocity ω of the first electric motor 36 ｅ１ , and DC voltage V ＤＣ Based on this, the first voltage command v ｄｑ１ ＊ The first voltage command v ｄｑ１ ＊ is a command for the voltage to be applied to the first electric motor 36. The first voltage command v ｄｑ１ ＊ is the d-axis voltage v of the first electric motor 36 ｄ１ (hereinafter, the first d-axis voltage command v ｄ１ ＊ ) and the q-axis voltage v of the first electric motor 36 ｑ１ (hereinafter, the first q-axis voltage command v ｑ１ ＊ The d-axis voltage v ｄ１ and the q-axis voltage v ｑ１ represents the voltage component of the first electric motor 36 in the dq-axis coordinate system.

[0046] The current control unit 42 also outputs a second current command i ｄｑ２ ＊ , the electrical angular velocity ω of the second electric motor 38 ｅ２ , and DC voltage V ＤＣ Based on this, the second voltage command v ｄｑ２ ＊ The second voltage command v ｄｑ２ ＊ is a command for the voltage to be applied to the second electric motor 38. ｄｑ２ ＊ is the d-axis voltage v of the second motor 38 ｄ２ (second d-axis voltage command v ｄ２ ＊ ) and the q-axis voltage v of the second motor 38 ｑ２ (second q-axis voltage command v ｑ２ ＊ ) and the d-axis voltage v ｄ２ and the q-axis voltage v ｑ２represents the voltage component of the second electric motor 38 in the dq-axis coordinate system.

[0047] The PWM control unit 43 outputs the first voltage command v ｄｑ１ ＊ , and the electrical angle Φ of the first electric motor 36 ｅ１ Based on this, the first PWM signal D １ ＊ The first PWM signal D １ ＊ is a PWM (Pulse Width Modulation) signal that determines the timing of switching each of the switching elements UP to WN of the first inverter 37. １ ＊ Is U １ Phase, V １ Phase and W １ The driving signals {D ｕｐ１ ＊ , D ｕｌ１ ＊ , D ｖｐ１ ＊ , D ｖｌ１ ＊ , D ｗｐ１ ＊ , D ｗｌ１ ＊}.

[0048] The first inverter 37 outputs the first PWM signal D １ ＊ By switching the switching elements UP-WN on and off in accordance with the above, the first unit phase current i ＵＶＷ１ Let it flow. ｗａｒｍ When the first unit phase current i ＵＶＷ１ is the first MTPA current command i ｄｑ１－ＭＴＰＡ ＊ The current value is determined by S ｗａｒｍ = 1 and the battery 10 needs to be warmed up, the first unit phase current i ＵＶＷ１ is the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ The current value depends on

[0049] Similarly, the PWM control unit 43 outputs the second voltage command vｄｑ２ ＊ , and the electrical angle φ of the second electric motor 38 ｅ２ Based on this, the second PWM signal D ２ ＊ The second PWM signal D ２ ＊ is a PWM signal that determines the timing of switching each of the switching elements UP-WN of the second inverter 39. ２ ＊ Is U ２ Phase, V ２ Phase and W ２ The driving signals {D ｕｐ２ ＊ , D ｕｌ２ ＊ , D ｖｐ２ ＊ , D ｖｌ２ ＊ , D ｗｐ２ ＊ , D ｗｌ２ ＊}.

[0050] The second inverter 39 outputs the second PWM signal D ２ ＊ By switching the switching elements UP-WN on and off in accordance with the above, the second motor 38 is supplied with the second unit phase current i ＵＶＷ２ Let it flow. ｗａｒｍ When the second unit phase current i ＵＶＷ２ is the second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ The current value is determined by S ｗａｒｍ = 1 and the battery 10 needs to be warmed up, the second unit phase current i ＵＶＷ２ is the second warm-up current command i ｄｑ２－ｈｅａｔ ＊ The current value depends on

[0051] The coordinate conversion unit 44 converts the first unit phase current i ＵＶＷ１ to the first dq axis current i ｄｑ１Similarly, the coordinate transformation unit 44 transforms the second unit phase current i ＵＶＷ２ to the second dq axis current i ｄｑ２ Specifically, the coordinate conversion unit 44 calculates the first dq-axis current i ｄｑ１ and the second dq axis current i ｄｑ２ Calculate the following.

[0052]

[0053] The first unit phase current i ＵＶＷ１ and the second unit phase current i ＵＶＷ２ are appropriately acquired by the first current sensor 48a and the second current sensor 48b, respectively. However, in this embodiment, as shown in the above formula (1), the coordinate conversion unit 44 converts U １ Phase current i Ｕ１ , V １ Phase current i Ｖ１ Obtain W １ Phase current i Ｗ１ is calculated by calculation (i Ｗ１ = -i Ｕ１ -i Ｖ１ Similarly, as shown in equation (2), the coordinate transformation unit 34 converts U ２ Phase current i Ｕ２ , V ２ Phase current i Ｖ２ Obtain W ２ Phase current i Ｗ２ is calculated by calculation (i Ｗ２ = -i Ｕ２ -i Ｖ２ ).

[0054] The rotation detection unit 45 detects the electrical angle φ of the first electric motor 36 based on the output signal of the rotation sensor 49 a provided in the first electric motor 36. ｅ１ , and electrical angular velocity ω ｅ１ Furthermore, the rotation detection unit 45 calculates the electrical angle φ of the second electric motor 38 based on the output signal of the rotation sensor 49b provided in the second electric motor 38. ｅ２ , and electrical angular velocity ω ｅ２ Calculate the following.

[0055] The rotation sensors 49a, 49b are configured by, for example, resolvers, and the rotation detection unit 35 is configured by an RDIC (resolver digital converter integrated circuit), an ABZ counter, and a speed calculator. In this case, the RDIC acquires an excitation signal and a modulation signal from the resolver, and based on these, outputs up / down counter pulses A, B and an origin signal pulse Z. Based on these ABZ signals, the ABZ counter calculates the electrical angle φ ｅ１ , φ ｅ２ Then, the speed calculator calculates the electrical angle φ ｅ１ , φ ｅ By differentiating with respect to time, the electrical angular velocity ω ｅ１ , ω ｅ２ Calculate the following.

[0056] Fig. 4 is a block diagram showing the configuration of the current command generating unit 41. As shown in Fig. 4, the current command generating unit 41 includes an MTPA current command generating unit 51, a warm-up current command generating unit 52, a current command selecting unit 53, and a gain setting unit 54.

[0057] The MTPA current command generating unit 51 generates a normal current command, i.e., an MTPA current command i by referring to the MTPA current command map. ｄｑ－ＭＴＰＡ ＊ The MTPA current command map is generated (calculated) based on the torque command, DC voltage V ＤＣ , and a map in which the electrical angular velocity and the current command in the MTPA control are previously associated with each other. In this embodiment, the first electric unit 11 and the second electric unit 12 have substantially equivalent configurations, so the MTPA current command map is common to the first electric unit 11 and the second electric unit 12.

[0058] Therefore, the MTPA current command generating unit 51 references the MTPA current command map to generate the first torque command T １ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the first electric motor 36 ｅ１ The first MTPA current command i ｄｑ１－ＭＴＰＡ ＊Similarly, the MTPA current command generation unit 51 calculates the second torque command T ２ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the second electric motor 38 ｅ２ The second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ Calculate the following.

[0059] The warm-up current command generator 52 generates a torque command, a DC voltage V ＤＣ , and a current command for warm-up control, i.e., a warm-up current command i ｄｑ－ｈｅａｔ ＊ Generate (calculate)

[0060] In this embodiment, the warm-up current command generating unit 52 generates the MTPA current command i according to the MTPA current command map. ｄｑ－ＭＴＰＡ ＊ and a current command according to the warm-up current command map 62 (hereinafter referred to as the basic warm-up current command idq-heatMAP ＊ Then, the warm-up current command generating unit 52 generates the weighted sum of these as the final warm-up current command i ｄｑ－ｈｅａｔ ＊ The MTPA current command i ｄｑ－ＭＴＰＡ ＊ and the basic warm-up current command idq-heatMAP ＊ Each weight of １ , k ２ The basic warm-up current command idq-heatMAP is determined by ＊ is the first basic warm-up current command idq1-heatMAP for the first electric unit 11 (first electric motor 36). ＊ and a second basic warm-up current command idq2-heatMAP for the second electric motor 38 (second electric unit 12). ＊ and Gain k １ is the first basic warm-up current command idq1-heatMAP ＊ is a parameter that determines the weight of １ Gain k is set within the range of ≦1. ２ is the second basic warm-up current command idq2-heatMAP ＊is a parameter that determines the weight of ２ It is set within the range of ≦1.

[0061] More specifically, the warm-up current command generator 52 generates a first torque command T １ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the first electric motor 36 ｅ１ In response to the first MTPA current command i ｄｑ１－ＭＴＰＡ ＊ and the first basic warm-up current command idq1-heatMAP ＊ Then, the warm-up current command generating unit 52 calculates the gain k １ The first MTPA current command i ｄｑ１－ＭＴＰＡ ＊ and the first basic warm-up current command idq1-heatMAP ＊ The weighted sum of the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ That is, i ｄｑ１－ｈｅａｔ ＊ = k １ ・idq1-heatMAP ＊ +(1-k １ )・i ｄｑ１－ＭＴＰＡ ＊ is.

[0062] Similarly, the warm-up current command generator 52 generates a second torque command T ２ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the second electric motor 38 ｅ２ In response to the second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ and the second basic warm-up current command idq2-heatMAP ＊ Then, the warm-up current command generating unit 52 calculates the gain k ２ The second MTPA current command i ｄｑ２－ＭＴＰＡ ＊ and the second basic warm-up current command idq2-heatMAP ＊ The weighted sum of the second warm-up current command i ｄｑ２－ｈｅａｔ ＊ That is, i ｄｑ２－ｈｅａｔ ＊ = k ２ ・idq2-heatMAP＊ +(1-k ２ )・i ｄｑ２－ＭＴＰＡ ＊ is.

[0063] In addition, the gain k １ , k ２ The gain k essentially represents the priority of heat generation when the first electric unit 11 and the second electric unit 12 are actively made to generate heat in order to warm up the battery 10. １ , k ２ The larger the value, the higher the priority of the heat generation.

[0064] The current command selector 53 selects the warm-up command S ｗａｒｍ Based on this, the MTPA current command i ｄｑ－ＭＴＰＡ ＊ Or warm-up current command i ｄｑ－ｈｅａｔ ＊ and the final first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ Output as

[0065] Specifically, S ｗａｒｍ = 0 and the warm-up of the battery 10 is not required, the current command selection unit 53 selects the MTPA current command i ｄｑ－ＭＴＰＡ ＊ = (i ｄｑ１－ＭＴＰＡ ＊ , i ｄｑ２－ＭＴＰＡ ＊ ) as the first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ On the other hand, S ｗａｒｍ = 1 and the battery 10 needs to be warmed up, the current command selector 53 selects the warm-up current command i ｄｑ－ｈｅａｔ ＊ = (i ｄｑ１－ｈｅａｔ ＊ , i ｄｑ２－ｈｅａｔ ＊ ) as the first current command i ｄｑ１ ＊ and the second current command i ｄｑ２ ＊ Output as

[0066] The gain setting unit 54 sets the gain k １ , k ２ The gain setting unit 54 sets, for example, the first torque command T １ ＊ , second torque command T ２ ＊ , first inverter temperature θ ＩＮＶ１ , second inverter temperature θ ＩＮＶ２ , first motor temperature θ ＭＯＴ１ , and second motor temperature θ ＭＯＴ２ Based on the above, the gain k １ , k ２ In this embodiment, the gain setting unit 54 sets the first torque command T １ ＊ , second torque command T ２ ＊ , first inverter temperature θ ＩＮＶ１ , and the second inverter temperature θ ＩＮＶ２ Based on this, the gain k １ , k ２ Set.

[0067] In particular, when warming up the battery 10 while the electric vehicle 100 is running, the gain setting unit 54 sets the gain k １ , k ２ In other words, the gain setting unit 54 sets k １ >k ２ or k ２ <k １ So that the gain k １ , k ２ As a result, the gain setting unit 54 sets the d-axis current of either the first electric unit 11 or the second electric unit 12 to be larger than the d-axis current of the other. As a result, one of the first electric unit 11 and the second electric unit 12 generates heat preferentially. That is, in this embodiment, when the battery 10 is warmed up while the electric vehicle 100 is running, the heat generation amount Q of the first electric unit 11 is １ (not shown) and the heat generation amount Q of the second electric unit 12 ２ (not shown) are different.

[0068] 5 is a block diagram showing the configuration of the gain setting unit 54. As shown in FIG. 5, the gain setting unit 54 includes a torque comparison unit 56, a gain determination unit 57, and an output unit 58.

[0069] The torque comparison unit 56 compares the torque output by the first electric unit 11 (first electric motor 36) and the second electric unit 12 (second electric motor 38). The torque comparison unit 56 also acquires the temperatures of the first electric unit 11 and the second electric unit 12. The torque comparison unit 56 then outputs the torque and temperature of the electric unit with a relatively large torque as the representative torque and representative temperature.

[0070] In this embodiment, the torque comparison unit 56 calculates a first torque command T １ ＊ and the second torque command T ２ ＊ In this embodiment, the torque comparator 56 uses the first inverter temperature θ as the temperature of the second electric unit 12 of the first electric unit 11. ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ Get.

[0071] Therefore, in this embodiment, T １ ＊ >T ２ ＊ , the torque comparison unit 56 compares the torque and temperature of the first electric unit 11, which has a relatively large torque, i.e., the first torque command T １ ＊ and the first inverter temperature θ ＩＮＶ１ are output as the representative torque and the representative temperature. １ ＊ <T ２ ＊ , the torque comparison unit 56 compares the torque and temperature of the second electric unit 12, which has a relatively small torque, i.e., the second torque command T ２ ＊ and second inverter temperature θ ＩＮＶ２ are output as the representative torque and the representative temperature.

[0072] In this embodiment, as described above, the representative torque is T１ ＊ or T ２ ＊ Therefore, in the following, the representative torque is T Ｘ ＊ The representative temperature is expressed as the first inverter temperature θ ＩＮＶ１ or second inverter temperature θ ＩＮＶ２ Therefore, in the following, the representative temperature is θ ＩＮＶ－Ｘ It is expressed as:

[0073] The gain determination unit 57 determines the representative torque T Ｘ ＊ and representative temperature θ ＩＮＶ－Ｘ Based on this, the final warm-up current command i of the electric unit with a relatively "large" torque is ｄｑ－ｈｅａｔ ＊ The gain used to calculate the alpha gain k α ) and the final warm-up current command i of the electric unit with a relatively "small" torque. ｄｑ－ｈｅａｔ ＊ The gain used to calculate the beta gain k β (hereinafter referred to as "the decision")

[0074] Specifically, the gain determination unit 57 determines the alpha gain k α and beta gain k β Determine.

[0075]

[0076] As shown in Table 1, the gain determination unit 57 determines the representative torque T Ｘ ＊ is set to a torque threshold value TH that is determined in advance based on an experiment, a simulation, or the like. Ｔ Compared with alpha gain k α and beta gain k β The gain determining unit 57 determines the value of the representative temperature θ ＩＮＶ－Ｘ is set to a predetermined temperature threshold value TH based on an experiment or a simulation. θ Compared with alpha gain k α and beta gain k β As shown in Table 1, the value of the representative torque TＸ ＊ and representative temperature θ ＩＮＶ－Ｘ The states of the first electric unit 11 and the second electric unit 12 determined by the above are referred to as state S ａ , state S Ｂ , state S Ｃ , and state S Ｄ That's what they say.

[0077] State S Ａ is the representative torque T Ｘ ＊ is the torque threshold TH Ｔ is greater than (T Ｘ ＊ >TH Ｔ ), and the representative temperature θ ＩＮＶ－Ｘ is the temperature threshold TH θ higher than (θ ＩＮＶ－Ｘ >TH θ ) state. Ｂ is the representative torque T Ｘ ＊ is the torque threshold TH Ｔ is greater than (T Ｘ ＊ >TH Ｔ ), and the representative temperature θ ＩＮＶ－Ｘ is the temperature threshold TH θ Below (θ ＩＮＶ－Ｘ ≦TH θ ) state. Ｃ is the representative torque T Ｘ ＊ is the torque threshold TH Ｔ is less than or equal to (T Ｘ ＊ ≦TH Ｔ ), and the representative temperature θ ＩＮＶ－Ｘ is the temperature threshold TH θ higher than (θ ＩＮＶ－Ｘ >TH θ ) state. Ｄ is the representative torque T Ｘ ＊ is the torque threshold TH Ｔ is less than or equal to (T Ｘ ＊ ≦TH Ｔ ), and the representative temperature θ ＩＮＶ－Ｘ is the temperature threshold TH θ Below (θ ＩＮＶ－Ｘ ≦TH θ) is in this state.

[0078] Each state S Ａ -S Ｄ Alpha gain k in α and beta gain k β Specific values ​​of k Ａ , k Ｂ , k Ｃ , k Ｄ , k Ｅ is 0≦k Ａ <k Ｂ <k Ｃ <k Ｄ <k Ｅ It is determined in advance based on experiments, simulations, etc. so as to satisfy k Ａ = 0 and k Ｅ = 1.

[0079] Specifically, the gain determination unit 57 determines the alpha gain k so that, in principle, the d-axis current of the electric unit with a relatively small torque between the first electric unit 11 and the second electric unit 12 is larger than the d-axis current of the electric unit with a relatively large torque. α and beta gain k β That is, the gain determination unit 57 determines the beta gain k β is the alpha gain k α (k α <k β ), alpha gain k α and beta gain k β Here, as shown in Table 1, the state S Ａ , state S Ｂ , and state S Ｃ In this case, the alpha gain k α Beta gain k β is larger.

[0080] In this embodiment, T Ｘ ＊ >TH Ｔ and θ ＩＮＶ－Ｘ >TH θ State S Ｂ In this case, the gain determination unit 57 determines k α = kＡ = 0 and k β = k Ｅ = 1. Therefore, the state S Ｂ Then, the electric unit having a relatively large torque between the first electric unit 11 and the second electric unit 12 is substantially the MTPA current command i ｄｑ－ＭＴＰＡ ＊ The electric unit having a relatively small torque is driven based on the basic warm-up current command idq-heatMAP ＊ Therefore, the d-axis current of the electric unit with a relatively large torque remains unchanged, and only the d-axis current of the electric unit with a relatively small torque increases.

[0081] Also, T Ｘ ＊ >TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S Ａ And, T Ｘ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ >TH θ State S Ｃ In this case, the gain determination unit 57 determines k β >k α >0, k α and k β Therefore, the state S Ａ and state S Ｃ In this case, the d-axis current of both the first electric unit 11 and the second electric unit 12 increases. However, the increase in the d-axis current of the electric unit with a relatively small torque is greater than the increase in the d-axis current of the electric unit with a relatively large torque.

[0082] In this embodiment, as described above, k Ｄ >k Ｂ Therefore, the state S Ａ and state S Ｃ Comparing the state S Ａ No.K α (= k Ｄ ) is the state S Ｃ No.K α (= k Ｂ) is larger than the representative torque T Ｘ ＊ is the torque threshold TH Ｔ A scene (state S Ｃ ) than the representative torque T Ｘ ＊ is the torque threshold TH Ｔ A scene larger than Ａ ) are more common.

[0083] In addition, the gain determination unit 57 exceptionally determines the alpha gain k so that the d-axis current of an electric unit with a relatively large torque is larger than the d-axis current of an electric unit with a relatively small torque. α and beta gain k β That is, the gain determination unit 57 may exceptionally determine the alpha gain k α is the beta gain k β (k α >k β ), alpha gain k α and beta gain k β Here, as shown in Table 1, the state S Ｄ In this case, the beta gain k β Alpha gain k α is larger.

[0084] In this embodiment, T Ｘ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S Ｄ In this case, the gain determination unit 57 determines whether 1=k α >k β >0 α and k β Therefore, the state S Ｄ In this case, the d-axis current of both the first electric unit 11 and the second electric unit 12 increases. Then, of the first electric unit 11 and the second electric unit 12, the electric unit with a relatively large torque substantially increases the basic warm-up current command idq-heatMAP ＊The electric unit having a relatively small torque is driven based on the basic warm-up current command idq-heatMAP ＊ and MTPA current command i ｄｑ－ＭＴＰＡ ＊ Beta gain k β Warm-up current command i by weighted sum according to ｄｑ－ｈｅａｔ ＊ As a result, the increase in the d-axis current of an electric unit with a relatively large torque is greater than the increase in the d-axis current of an electric unit with a relatively small torque.

[0085] The output unit 58 outputs the first torque command T １ ＊ and the second torque command T ２ ＊ Depending on the magnitude relationship of α and beta gain k β , the gain k １ , k ２ Specifically, T １ ＊ >T ２ ＊ , the output section 58 outputs the gain k １ Alpha gain k α and assign a gain k ２ Beta gain k β That is, the output unit 58 assigns (k １ , k ２ ) = (k α , k β ) the gain k １ , k ２ On the other hand, T １ ＊ <T ２ ＊ , the output section 58 outputs the gain k １ Alpha gain k α and assign a gain k ２ Beta gain k β That is, the output unit 58 assigns (k １ , k ２ ) = (k β , k α ) the gain k １ , k ２Output.

[0086] FIG. 6 is a block diagram showing the configuration of the warm-up current command generator 52. Here, the first torque command T １ ＊ , DC voltage V ＤＣ , the electrical angular velocity ω of the first electric motor 36 ｅ１ , and gain k １ Based on this, the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ This shows the part that calculates the second torque command T ２ ＊ , DC voltage V ＤＣ , the electrical angular velocity ω of the second electric motor 38 ｅ２ , and gain k ２ Based on this, the second warm-up current command i ｄｑ２－ｈｅａｔ ＊ The part that calculates is configured in the same way.

[0087] As shown in FIG. 6 , the warm-up current command generating unit 52 includes an MTPA current command map 61 , a warm-up current command map 62 , and a weighting adder 63 .

[0088] The MTPA current command map 61 is generated based on an experiment or a simulation, etc., by calculating a torque command, a DC voltage V ＤＣ , and the electrical angular velocity and the MTPA current command i ｄｑ－ＭＴＰＡ ＊ Therefore, the warm-up current command generating unit 52 references the MTPA current command map 61 to generate the first torque command T １ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the first electric motor 36 ｅ１ The first MTPA current command i ｄｑ１－ＭＴＰＡ ＊ Calculate the following.

[0089] The MTPA current command map 61 used by the warm-up current command generator 52 is the same as the MTPA current command map used by the MTPA current command generator 51. Therefore, the warm-up current command generator 52 receives the MTPA current command i from the MTPA current command generator 51 instead of performing calculations by itself. ｄｑ－ＭＴＰＡ ＊In addition, the warm-up current command generating unit 52 can obtain the MTPA current command i ｄｑ－ＭＴＰＡ ＊ to the current command selection unit 53 , the warm-up current command generation unit 52 can also function as the MTPA current command generation unit 51 .

[0090] The warm-up current command map 62 is generated based on an experiment or a simulation, etc., and is calculated based on a torque command, a DC voltage V ＤＣ , and the electrical angular velocity and the basic warm-up current command idq-heatMAP ＊ Therefore, the warm-up current command generating unit 52 references the MTPA current command map 61 to generate the first torque command T １ ＊ , DC voltage V ＤＣ , and the electrical angular velocity ω of the first electric motor 36 ｅ１ First basic warm-up current command idq1-heatMAP according to ＊ Calculate the following.

[0091] As shown in FIG. 6, the weighting adder 63 calculates a gain k １ In response to the first basic warm-up current command idq1-heatMAP ＊ and MTPA current command i ｄｑ－ＭＴＰＡ ＊ Then, the weighted adder 63 calculates the weighted sum of the first warm-up current command i ｄｑ１－ｈｅａｔ ＊ Output as

[0092] 7 is a block diagram showing the configuration of the current control unit 42. In FIG. 7, the first current command i ｄｑ１ ＊ , the electrical angular velocity ω of the first electric motor 36 ｅ１ , and DC voltage V ＤＣ Based on this, the first voltage command v ｄｑ１ ＊ The second current command i ｄｑ２ ＊ , the electrical angular velocity ω of the second electric motor 38 ｅ２ , and DC voltage V ＤＣ Based on this, the second voltage command v ｄｑ２ ＊The configuration for generating (calculating) is similar to this.

[0093] As shown in FIG. 7, the current control unit 42 includes a decoupling voltage table 71 , LPFs 72 and 73 , and PI controllers 74 and 75 .

[0094] The decoupling voltage table 71 is generated based on an experiment or a simulation, etc., by calculating the first current command i ｄｑ１ ＊ , electrical angular velocity ω ｅ１ , and DC voltage V ＤＣ and the decoupling voltage v ｄｑ１－ｄｃｐｌ The decoupling voltage v ｄｑ１－ｄｃｐｌ is the d-axis voltage v of the first electric unit 11 (first electric motor 36) ｄ１ and the q-axis voltage v ｑ１ represents the voltage value for canceling (decoupling) the interference component of ｄｑ１－ｄｃｐｌ is the d-axis voltage v ｄ１ The decoupling voltage for ｄ１－ｄｃｐｌ ) and the q-axis voltage v ｑ１ The decoupling voltage for the q-axis (hereinafter referred to as the q-axis decoupling voltage v ｑ１－ｄｃｐｌ It is composed of the following parts:

[0095] The LPFs 72 and 73 are connected to the d-axis decoupling voltage v ｄ１－ｄｃｐｌ and the q-axis decoupling voltage v ｑ１－ｄｃｐｌ The LPFs 72 and 73 are low-pass filters that reduce the high frequency components of the first dq-axis current i ｄｑ１ Using the reference response time constant τ, it is expressed by the following equation (3).

[0096]

[0097] The PI controller 74 calculates the command value (i ｄ１ ＊ ) and the detected value (i ｄ１ ) based on the deviation of the detected value (i ｄ１ ) is the command value (i ｄ１ ＊ ) so that the d-axis control voltage v ｄ１－ＰＩ Similarly, the PI controller 75 calculates the command value (iｑ１ ＊ ) and the detected value (i ｑ１ ) based on the deviation of the detected value (i ｑ１ ) is the command value (i ｑ１ ＊ ) so that the q-axis control voltage v ｑ１－ＰＩ Calculate the following.

[0098] The PI controllers 74 and 75 have proportional gains k ｐｄ , k ｐｑ , and integral gain k ｉｄ , k ｉｑ is expressed by the following equation (4).

[0099]

[0100] In addition, the proportional gain k ｐｄ , k ｐｑ , and integral gain k ｉｄ , k ｉｑ is the d-axis inductance L of the first electric motor 36 ｄ and q-axis inductance L ｑ , winding resistance R, and the first dq axis current i ｄｑ１ Using the reference response time constant τ, for example, it is expressed by the following equation (5).

[0101]

[0102] Then, the current control unit 42 outputs the d-axis control voltage v calculated as above. ｄ１－ＰＩ The value obtained by adding the filtered d-axis non-interacting voltage vd1-dcpl-flt to the first d-axis voltage command v ｄ１ ＊ Similarly, the current control unit 42 outputs the q-axis control voltage v ｑ１－ＰＩ The value obtained by adding the filtered q-axis decoupling voltage vq1-dcpl-flt to the first q-axis voltage command v ｑ１ ＊ Output as

[0103] 8 is a block diagram showing the configuration of the PWM control unit 43. In FIG. ｄｑ１ ＊ , and the electrical angle φ of the first electric motor 36 ｅ１ Based on this, the first PWM signal D １＊ Here, the second voltage command v ｄｑ２ ＊ , and the electrical angle φ of the second electric motor 38 ｅ２ Based on this, the second PWM signal D ２ ＊ The configuration for generating is similar to this.

[0104] As shown in FIG. 8, the PWM control unit 43 includes a coordinate conversion unit 81 , a duty ratio calculation unit 82 , and a drive signal generator 83 .

[0105] The coordinate conversion unit 81 converts the first voltage command v ｄｑ１ ＊ to the three-phase voltage command value v ＵＶＷ１ ＊ = (v Ｕ１ ＊ , v Ｖ１ ＊ , v Ｗ１ ＊ ) is calculated.

[0106]

[0107] The duty ratio calculation unit 82 calculates U １ , V １ , W １ The duty command values ​​Duty-u1, Duty-v1, and Duty-w1 of the respective phases are calculated. In equation (7), U １ Only the duty command value Duty-u1 of the phase is shown, but V １ The duty command values ​​Duty-v1 and Duty-w1 for the W1-phase and W2-phase are calculated in the same manner.

[0108]

[0109] The drive signal generator 83 generates the first PWM signal D by, for example, so-called triangular wave comparison PWM control. １ ＊ That is, the drive signal generator 83 generates U by comparing and matching a carrier triangular wave with a constant frequency and the duty command values ​​Duty-u1, Duty-v1, and Duty-w1 of the respective phases. １ Phase, V １ Phase and W １The driving signals {D ｕｐ１ ＊ , D ｕｌ１ ＊ , D ｖｐ１ ＊ , D ｖｌ１ ＊ , D ｗｐ１ ＊ , D ｗｌ１ ＊} is generated.

[0110] The operation of the warm-up control of the battery 10 in the electric vehicle 100 configured as described above will be described below.

[0111] 9 is a flowchart relating to the warm-up control during running. As shown in FIG. 9, in step S10, the current command generating unit 41 generates the MTPA current command i ｄｑ－ＭＴＰＡ ＊ = (i ｄｑ１－ＭＴＰＡ ＊ , i ｄｑ２－ＭＴＰＡ ＊ In step S11, the current command generator 41 generates a warm-up command S ｗａｒｍ It is determined whether the battery 10 needs to be warmed up by the above.

[0112] In step S11, S ｗａｒｍ = 0, and if warming up of the battery 10 is not necessary, the process proceeds to step S20, and the MTPA current command i ｄｑ－ＭＴＰＡ ＊ = (i ｄｑ１－ＭＴＰＡ ＊ , i ｄｑ２－ＭＴＰＡ ＊ ) the first electric unit 11 and the second electric unit 12 are controlled in accordance with the above.

[0113] On the other hand, in step S11, ｗａｒｍ If the value of the first torque command T １ ＊ and a second torque command T ２ ＊ Compare with.

[0114] In step S12, T １ ＊ >T ２ ＊ When the torque of the first electric unit 11 is relatively large, the torque comparison unit 56 outputs the first torque command T １ ＊ is the representative torque T Ｘ ＊ and the first inverter temperature θ ＩＮＶ１ The representative temperature θ ＩＮＶ－Ｘ Let's say.

[0115] Then, in step S13, the gain determination unit 57 calculates the representative torque T Ｘ ＊ The first torque command T １ ＊ and torque threshold TH Ｔ In step S13, T Ｘ ＊ =T １ ＊ >TH Ｔ If so, the process proceeds to step S14. Ｘ ＊ =T １ ＊ ≦TH Ｔ If so, the process proceeds to step S15, where the gain determining unit 57 further determines the representative temperature θ ＩＮＶ－Ｘ The first inverter temperature θ ＩＮＶ１ the temperature threshold TH θ Then, in step S15, θ ＩＮＶ－Ｘ = θ ＩＮＶ１ >TH θ If θ ＩＮＶ－Ｘ = θ ＩＮＶ１ ≦TH θ If so, the process proceeds to step S16.

[0116] That is, T １ ＊ >T ２ ＊ , the torque of the first electric unit 11, which has a relatively large torque (first torque command T １ ＊) and temperature (first inverter temperature θ ＩＮＶ１ The state of the first electric unit 11, which has a relatively large torque, is determined based on the state S in Table 1. Ａ , S Ｂ , S Ｃ If either of the above is true, the process proceeds to step S14, and the state of the first electric unit 11 and the second electric unit 12 is determined to be in the state S Ｄ If so, the process proceeds to step S16.

[0117] On the other hand, in step S12, T １ ＊ <T ２ ＊ When the torque of the second electric unit 12 is relatively large, the torque comparison unit 56 outputs the second torque command T ２ ＊ is the representative torque T Ｘ ＊ and the second inverter temperature θ ＩＮＶ２ The representative temperature θ ＩＮＶ－Ｘ Let's say.

[0118] Then, in step S17, the gain determination unit 57 calculates the representative torque T Ｘ ＊ The second torque command T ２ ＊ and torque threshold TH Ｔ In step S17, T Ｘ ＊ =T ２ ＊ >TH Ｔ If so, the process proceeds to step S16. Ｘ ＊ =T ２ ＊ ≦TH Ｔ If so, the process proceeds to step S18, where the gain determining unit 57 further determines the representative temperature θ ＩＮＶ－Ｘ The second inverter temperature θ ＩＮＶ２ the temperature threshold TH θ Then, in step S18, θ ＩＮＶ－Ｘ = θ ＩＮＶ２ >TH θIf θ ＩＮＶ－Ｘ = θ ＩＮＶ２ ≦TH θ If so, the process proceeds to step S16.

[0119] That is, T １ ＊ <T ２ ＊ , the torque of the second electric unit 12, which has a relatively large torque (second torque command T ２ ＊ ) and temperature (second inverter temperature θ ＩＮＶ２ The state of the second electric unit 12, which has a relatively large torque, is determined based on the state S in Table 1. Ａ , S Ｂ , S Ｃ On the other hand, if the second electric unit 12, which has a relatively large torque, is in the state S Ｄ If so, the process proceeds to step S14.

[0120] In step S14, the gain determination unit 57 and the output unit 58 determine the gain k １ , k ２ is k １ <k ２ That is, it is set so as to satisfy the relationship T １ ＊ >T ２ ＊ When the torque of the second electric motor unit 12 is relatively small, the gain k ２ is the gain k of the first electric unit 11 having a relatively large torque. １ On the other hand, T １ ＊ <T ２ ＊ If T ２ ＊ ≦TH Ｔ and θ ＩＮＶ２ ≦TH θ In exceptional cases (state S Ｄ ), the gain k of the second electric unit 12 having a relatively large torque is ２ However, the gain k of the first electric unit 11, which has a relatively small torque,１ becomes larger than

[0121] In step S16, the gain determination unit 57 and the output unit 58 determine the gain k １ , k ２ is k １ >k ２ That is, it is set so as to satisfy the relationship T １ ＊ <T ２ ＊ When the torque of the first electric unit 11 is relatively small, the gain k １ is the gain k of the second electric motor unit 12 having a relatively large torque. ２ On the other hand, T １ ＊ >T ２ ＊ If T １ ＊ ≦TH Ｔ and θ ＩＮＶ１ ≦TH θ In exceptional cases (state S Ｄ ), the gain k of the first electric unit 11 having a relatively large torque is １ is the gain k of the second electric motor unit 12, which has a relatively small torque. ２ becomes larger than

[0122] In step S19, the warm-up current command generating unit 52 calculates the gain k １ , k ２ Based on this, the basic warm-up current command idq-heatMAP ＊ and MTPA current command i ｄｑ－ＭＴＰＡ ＊ By weighting and adding the above, the final warm-up current command i ｄｑ－ｈｅａｔ ＊ Then, in step S20, the final warm-up current command i ｄｑ－ｈｅａｔ ＊ Based on this, the first electric unit 11 and the second electric unit 12 are controlled.

[0123] 10 is an explanatory diagram showing transitions of the operating points of the first electric unit 11 and the second electric unit 12 in a comparative example. The comparative example is an example in which when warming up of the battery 10 is required while the electric vehicle 100 is running, only the d-axis current of the first electric unit 11 is always increased, regardless of the state of the first electric unit 11 and the second electric unit 12, thereby increasing the heat generation amount of the first electric unit 11. In FIG. 10, in the dq-axis coordinate system, the constant torque curve is shown by a solid line, and the MTPA curve is shown by a dashed line. Also, for the sake of explanation, T １ ＊ >T ２ ＊ In FIG. 10, the operating point of the first electric unit 11 before the warm-up of the battery 10 is A １ and the operating point of the second electric unit 12 is B １ is.

[0124] As shown in FIG. 10, when the battery 10 needs to be warmed up while the electric vehicle 100 is running, in the comparative example, regardless of the states of the first electric unit 11 and the second electric unit 12, the operating point of the first electric unit 11 moves along the constant torque curve, for example, as shown in FIG. １ From A ２ and the operating point of the second electric unit 12 is changed to B １ As a result, the d-axis current i ｄ１ increases, and the amount of heat generated by the first electric unit 11 increases.

[0125] However, the first electric unit 11 is operated at the operating point A ２ When the first electric unit 11 is driven at a current of 100 V, the temperature of the first electric unit 11 may exceed its heat-resistant temperature. In this case, the current of the first electric unit 11 is limited so as not to exceed its heat-resistant temperature, and the operating point of the first electric unit 11 is set to A ２ From A ３ Therefore, the d-axis current of the first electric motor unit 11 is the planned d-axis current (operating point A ２ d-axis current in the battery 10), which results in insufficient warm-up of the battery 10. That is, in the comparative example, it takes a long time for the warm-up of the battery 10 to be completed.

[0126] 11 is an explanatory diagram showing transitions of the operating points of the first electric unit 11 and the second electric unit 12 in this embodiment. As described above, this embodiment is an example in which, when warming up of the battery 10 is required while the electric vehicle 100 is traveling, the d-axis current of one of the first electric unit 11 and the second electric unit 12 is made larger than the d-axis current of the other depending on the state of the first electric unit 11 and the second electric unit 12, thereby causing one of the first electric unit 111 and the second electric unit 12 to generate heat preferentially. In FIG. 11, in the dq-axis coordinate system, the constant torque curve is shown by a solid line and the MTPA curve is shown by a dashed line. For the sake of explanation, the constant torque curve is shown by a solid line and the MTPA curve is shown by a dashed line. １ ＊ >T ２ ＊ , T １ ＊ >TH Ｔ , and θ ＩＮＶ１ ≦TH θ (State S Ａ 11, the operating point of the first electric unit 11 (operating point of the MTPA control) before the warm-up of the battery 10 is required is A １ The operating point of the second electric unit 12 (operating point of the MTPA control) is B １ is.

[0127] As shown in FIG. 11 , when the battery 10 needs to be warmed up while the electric vehicle 100 is traveling, in this embodiment, the operating point of the first electric unit 11, the operating point of the second electric unit 12, or both of them change depending on the states of the first electric unit 11 and the second electric unit 12. Here, the state of the first electric unit 11, which has a relatively large torque, is state S in Table 1. Ａ Since the first electric unit 11 and the second electric unit 12 are in the state of １ , B １ The d-axis current transitions from

[0128] Specifically, for example, the operating point of the first electric unit 11 is set to A along the constant torque curve. １ From A ４ The operating point of the second electric unit 12 is shifted to B along the constant torque curve.１ From B ２ That is, the transition of the operating point of the first electric unit 11, which has a relatively large torque, is suppressed, and the operating point of the second electric unit 12, which has a relatively small torque, is largely transitioned. Therefore, the d-axis current i ｄ２ The increase in the d-axis current i of the first electric motor unit 11 ｄ１ The increase in the operating points A after the transition of the first electric unit 11 and the second electric unit 12 is larger than the increase in the operating points A after the transition of the first electric unit 11 and the second electric unit 12. ４ , B １ In either case, the operating points are such that the heat resistance temperatures of the first electric unit 11 and the second electric unit 12 are not exceeded.

[0129] As a result, the current of the first electric unit 11 and the second electric unit 12 is not limited, and the heat generation amount of the first electric unit 11 and the second electric unit 12 as a whole can be increased compared to the comparative example, and the warm-up of the battery 10 can be sufficiently promoted. That is, in this embodiment, the warm-up of the battery 10 is completed earlier.

[0130] 12A and 12B are graphs showing the operation of the warm-up control. ｄｃ１ and the second unit DC current i ｄｃ２ 12(B) shows the transition of the first inverter temperature θ ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ 12C shows the total heat generation amount Q of the first electric unit 11 and the second electric unit 12 in the comparative example. ａｌｌ 12(D) shows the transition of the first unit DC current i ｄｃ１ and the second unit DC current i ｄｃ２ 12(E) shows the transition of the first inverter temperature θ ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ 12(F) shows the total heat generation amount Q of the first electric unit 11 and the second electric unit 12 in this embodiment. ａｌｌ The transition of [W] is shown.

[0131] In FIG. 12(A) and FIG. 12(D), the first unit DC current i ｄｃ１ is shown by a solid line, and the second unit DC current i ｄｃ２ is shown by a dashed line. １ -A ４ The first unit DC current i ｄｃ１ respectively Ａ１ -i Ａ４ and operating point B １ -B ２ The second unit DC current i ｄｃ２ respectively Ｂ１ -i Ｂ２ It is expressed as:

[0132] In FIG. 12(B) and FIG. 12(E), the first inverter temperature θ ＩＮＶ１ is shown by a solid line, and the second inverter temperature θ ＩＮＶ２ is shown by a dashed line. ｌｉｍ is the heat resistance temperature of the first inverter 37 and the second inverter 39.

[0133] 12(A) to 12(F), the horizontal axis represents time [s]. In FIG. 12(A) to 12(F), time zero is the time when the electric vehicle 100 starts traveling, and time t １ is the warm-up command S ｗａｒｍ is S ｗａｒｍ = 0 to S ｗａｒｍ = 1, and it is determined that the battery 10 needs to be warmed up. ２ is the first inverter temperature θ ＩＮＶ１ is the heat resistance temperature θ ｌｉｍ is the time when

[0134] As shown in FIG. 12A, T １ ＊ >T ２ ＊ Therefore, at time t １ From before, the first unit DC current i ｄｃ１ is the second unit DC current i ｄｃ２ Therefore, as shown in FIG. 12B, the first inverter temperature θ ＩＮＶ１ (Solid line) is the second inverter temperature θ ＩＮＶ２ It is higher than the dashed line.

[0135] In this state, at time t １ to S ｗａｒｍ = 1, in the comparative example, the operating point of the first electric unit 11 is A １ From A ２ Therefore, as shown in FIG. 12A, the first unit DC current i ｄｃ１ Is I Ａ１ From i Ａ２ As a result, the warm-up of the battery 10 is accelerated, and the first inverter temperature θ ＩＮＶ１ will rise further.

[0136] However, as shown in FIG. 12(B), soon after the time t ２ Heat resistance temperature θ ｌｉｍ Therefore, as shown in FIG. 12A, the operating point of the first electric unit 11 exceeds A ２ From A ３ and the first unit DC current i ｄｃ１ Is I Ａ２ From i Ａ３ decreases to.

[0137] As a result, as shown in FIG. 12C, the total heat generation amount Q of the first electric unit 11 and the second electric unit 12 in the comparative example ａｌｌ is the time t １ From time t ２ Although it rises sharply temporarily during the ２ Therefore, in the comparative example, it takes a long time for the battery 10 to warm up completely.

[0138] As shown in FIG. 12D, in this embodiment, T １ ＊ >T ２ ＊ Therefore, at time t １ From before, the first unit DC current i ｄｃ１ is the second unit DC current i ｄｃ２ Therefore, as shown in FIG. 12(E), the first inverter temperature θ ＩＮＶ１ (Solid line) is the second inverter temperature θ ＩＮＶ２ It is higher than the dashed line.

[0139] In this state, at time t １ to S ｗａｒｍ = 1, in this embodiment, the operating point of the first electric unit 11 becomes A １ From A ４ The operating point of the second electric unit 12 changes to B １ From B ２ Therefore, as shown in FIG. 12(D), the first unit DC current i ｄｃ１ (solid line) is i Ａ１ From i Ａ４ (<i Ａ３ <i Ａ２ ) and the second unit DC current i ｄｃ２ (Dash line) is i Ｂ１ From i Ｂ２ For example, the magnitude relationship between the currents is Ｂ１ <i Ａ１ <i Ａ４ <i Ｂ２ <i Ａ３ <i Ａ２ is.

[0140] Therefore, as shown in FIG. 12(E), in this embodiment, the first inverter temperature θ ＩＮＶ１ (solid line) and second inverter temperature θ ＩＮＶ２ (dashed line) increases, but in both cases the heat resistance temperature θ ｌｉｍ That is, even if the warm-up control is started, neither the first electric unit 11 nor the second electric unit 12 reaches an overheated state. Therefore, neither the first electric unit 11 nor the second electric unit 12 is subjected to current limitation.

[0141] As a result, as shown in FIG. 12(F), in this embodiment, at the time t １ Hereinafter, the total heat generation amount Q of the first electric unit 11 and the second electric unit 12 ａｌｌ rises, and the total heat generation Q ａｌｌ In this embodiment, the time t １ Subsequent total heat generation Q ａｌｌ is the time t １ -t ２ The maximum total heat generation Q ａｌｌ Therefore, in this embodiment, the warm-up of the battery 10 is completed early.

[0142] [First Modification] In the above embodiment, the gain setting unit 54 sets the gain k so that the d-axis current of an electric unit with a relatively small torque is larger than the d-axis current of an electric unit with a relatively large torque. １ , k ２ However, the gain setting unit 54 sets the gain k so that the d-axis current of the electric unit with a relatively low temperature is larger than the d-axis current of the electric unit with a relatively high temperature. １ , k ２ can be set.

[0143] 13 is a block diagram showing the configuration of the gain setting unit 54 according to the first modified example. As shown in FIG. 13, the gain setting unit 54 according to the first modified example includes a temperature comparison unit 91, a gain determination unit 92, and an output unit 93.

[0144] The temperature comparison unit 91 compares the temperatures of the first electric unit 11 and the second electric unit 12. The temperature comparison unit 91 also acquires the torque output by the first electric unit 11 (first electric motor 36) and the second electric unit 12 (second electric motor 38). The temperature comparison unit 91 then outputs the torque and temperature of the electric unit with a relatively high temperature as the representative torque and representative temperature.

[0145] Here, the temperature comparison unit 91 uses the first inverter temperature θ as the temperature of the first electric unit 11 and the second electric unit 12. ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ The temperature comparator 91 also uses the first torque command T １ ＊ and the second torque command T ２ ＊ Get.

[0146] Therefore, in the first modified example, θ ＩＮＶ１ >θ ＩＮＶ２ , the temperature comparison unit 91 compares the torque and temperature of the first electric unit 11, which has a relatively high temperature, that is, the first torque command T １ ＊ and the first inverter temperature θ ＩＮＶ１is the representative torque T Ｘ ＊ and representative temperature θ ＩＮＶ－Ｘ On the other hand, θ ＩＮＶ１ <θ ＩＮＶ２ , the temperature comparison unit 91 compares the torque and temperature of the second electric unit 12, which has a relatively high temperature, i.e., the second torque command T ２ ＊ and second inverter temperature θ ＩＮＶ２ , the representative torque T Ｘ ＊ and representative temperature θ ＩＮＶ－Ｘ Output as

[0147] The gain determination unit 92 determines the representative torque T Ｘ ＊ and representative temperature θ ＩＮＶ－Ｘ Based on this, the final warm-up current command i of the electric unit with a relatively high temperature is ｄｑ－ｈｅａｔ ＊ The alpha gain k used to calculate α and the final warm-up current command i of the electric unit with a relatively low temperature. ｄｑ－ｈｅａｔ ＊ The beta gain k used to calculate β Specifically, the gain determination unit 92 determines the alpha gain k α and beta gain k β Determine.

[0148] The output unit 93 outputs the first inverter temperature θ ＩＮＶ１ and second inverter temperature θ ＩＮＶ２ Depending on the magnitude relationship of α and beta gain k β , the gain k １ , k ２ Specifically, θ ＩＮＶ１ >θ ＩＮＶ２ , the output section 58 outputs the gain k １ Alpha gain k α and assign a gain k ２ Beta gain k β That is, the output unit 93 assigns (k １ , k ２ ) = (k α, k β ) the gain k １ , k ２ On the other hand, θ ＩＮＶ１ <θ ＩＮＶ２ , the output section 58 outputs the gain k １ Alpha gain k α and assign a gain k ２ Beta gain k β That is, the output unit 93 assigns (k １ , k ２ ) = (k β , k α ) the gain k １ , k ２ Output.

[0149] In this way, the gain setting unit 54 sets the gain k so that the d-axis current of the electric unit with a relatively low temperature is larger than the d-axis current of the electric unit with a relatively high temperature. １ , k ２ Similarly to the above embodiment, when the above-described setting is made, even when the battery 10 is warmed up while the electric vehicle 100 is running, the warming up of the battery 10 can be promoted without causing current limitation.

[0150] [Second Modification] In the above embodiment, the warm-up current command generator 52 generates the warm-up current command using the gain k set by the gain setting unit 54. １ , k ２ is used as it is, the warm-up current command i ｄｑ－ｈｅａｔ ＊ However, the warm-up current command generating unit 52 generates (calculates) the corrected gain k １ , k ２ Using the above, the warm-up current command i ｄｑ－ｈｅａｔ ＊ can be generated (calculated).

[0151] Fig. 14 is a block diagram showing the configuration of the current command generator 41 of the second modified example. As shown in Fig. 14, the current command generator 41 of the second modified example includes a gain corrector 94 in addition to an MTPA current command generator 51, a warm-up current command generator 52, a current command selector 53, and a gain setter 54.

[0152] The MTPA current command generating unit 51, the current command selecting unit 53, and the gain setting unit 54 are configured in the same manner as in the above embodiment or the first modified example.

[0153] The gain correction unit 94 calculates the DC voltage V ＤＣ , and the maximum output power P ＤＣ－ｌｉｍ The gain k set by the gain setting unit 54 based on [W] １ , k ２ By correcting the correction gain k １ ', k ２ Calculate the maximum output power P ＤＣ－ｌｉｍ is the actual maximum output power of the battery 10, which is temporarily or continuously limited depending on a drop in temperature, etc. The controller 13 functioning as the BMS calculates the maximum output power P ＤＣ－ｌｉｍ can be obtained appropriately.

[0154] Then, the warm-up current command generating unit 52 calculates the gain k set by the gain setting unit 54. １ , k ２ Instead of １ ', k ２ ', the warm-up current command i ｄｑ－ｈｅａｔ ＊ The correction gain k １ ', k ２ ', the warm-up current command generating unit 52 generates the warm-up current command i ｄｑ－ｈｅａｔ ＊ The specific method for generating is the same as in the above embodiment.

[0155] 15 is a block diagram showing the configuration of the gain correction unit 94. As shown in FIG. 15, the gain correction unit 94 is made up of, for example, an available output current calculation unit 95, a division unit 96, and a multiplication unit 97.

[0156] The outputtable current calculation unit 95 calculates, for example, the maximum output power P ＤＣ－ｌｉｍ and DC voltage V ＤＣ Based on this, the actual outputtable current I of the battery 10 is ｌｉｍ [A] is calculated. Here, I ｌｉｍ =P ＤＣ－ｌｉｍ / V ＤＣ is.

[0157] The division unit 96 calculates the maximum output current I ＭＡＸ and the current output current I ｌｉｍ Here, the divider 96 calculates the ratio of the maximum output current I ＭＡＸ Outputtable current I ｌｉｍ Ratio I ｌｉｍ / I ＭＡＸ The maximum output current I of the battery 10 according to the specifications is calculated. ＭＡＸ is a constant that is predetermined depending on the specific configuration of the battery 10, and is a parameter known to the controller 13 that functions as a BMS.

[0158] The multiplication unit 97 multiplies the basic gain k calculated by the gain setting unit 54 by １ , k ２ Compared to ｌｉｍ / I ＭＡＸ By multiplying by １ ', k ２ ' is calculated.

[0159] As described above, the actual output current I of the battery 10 ｌｉｍ Using the correction gain k １ ', k ２ ' is calculated and the warm-up current command i ｄｑ－ｈｅａｔ ＊ When the maximum output power P ＤＣ－ｌｉｍ Even if the warm-up current command i ｄｑ－ｈｅａｔ ＊ Therefore, the maximum output power P of the battery 10 is ＤＣ－ｌｉｍ Even if the maximum output power P ＤＣ－ｌｉｍ Within this range, the warm-up of the battery 10 is promoted to a substantially maximum extent.

[0160] As described above, the control method for an electric vehicle according to the above embodiment and each modification is a control method for an electric vehicle 100 having a first electric unit 11 and a second electric unit 12 that generate torque for traveling, and a battery 10 that supplies power to the first electric unit 11 and the second electric unit 12, in which heat generated in the first electric unit 11 and the second electric unit 12 is used to warm up on-board equipment (e.g., the battery 10). In this control method, when it becomes necessary to warm up the on-board equipment (10) while the electric vehicle 100 is traveling, the d-axis current of the first electric unit 11, the second electric unit 12, or the first electric unit 11 and the second electric unit 12 is increased, thereby increasing the heat generated by the entire first electric unit 11 and the second electric unit 12. At this time, depending on the state of the first electric unit 11 and the second electric unit 12, the d-axis current of either the first electric unit 11 or the second electric unit 12 is made larger than the d-axis current of the other, thereby causing either the first electric unit 11 or the second electric unit 12 to generate heat preferentially.

[0161] In this way, when the electric vehicle 100 has the first electric unit 11 and the second electric unit 12, by preferentially causing one of the first electric unit 11 and the second electric unit 12 to generate heat depending on the state of the first electric unit 11 and the second electric unit 12, it is possible to prevent the first electric unit 11 and the second electric unit 12 from overheating and increase the overall heat generation amount of the first electric unit 11 and the second electric unit 12. This allows the warm-up of on-board equipment such as the battery 10 to be completed quickly.

[0162] In the control method for the electric vehicle according to the above embodiment, the torque (T １ ＊ , T ２ ＊ ) and the d-axis current of the electric unit with a relatively small torque is made larger than the d-axis current of the electric unit with a relatively large torque.

[0163] Electric units with a larger torque distribution have higher inverter temperatures and the like before warm-up control begins, making them more likely to overheat when warm-up control begins. For this reason, by increasing the d-axis current of electric units with a smaller torque distribution and allowing them to generate heat preferentially, as described above, it is possible to increase the overall heat generation of the first electric unit 11 and the second electric unit 12 without causing them to overheat.

[0164] In the control method for the electric vehicle according to the above embodiment, the torque of the electric unit having a relatively large torque is set as the representative torque (T Ｘ ＊ ) and the representative torque (T Ｘ ＊ ) is a predetermined torque threshold (TH Ｔ ), the temperature of the electric unit with a relatively large torque is set as the representative temperature (θ ＩＮＶ－Ｘ ) and the representative temperature (θ ＩＮＶ－Ｘ ) is a predetermined temperature threshold (TH θ ) and compare it with the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) or less, and the representative temperature (θ ＩＮＶ－Ｘ ) is the temperature threshold (TH θ ) or less (state S Ｄ ) Exceptionally, the d-axis current of an electric unit having a relatively large torque is made larger than the d-axis current of an electric unit having a relatively small torque.

[0165] In this way, T Ｘ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S ＤIn the case of an electric unit with a relatively large torque, the current required for torque output is small and the inverter temperature is also sufficiently low. Therefore, even if the d-axis current is increased significantly in an electric unit with a relatively large torque, the electric unit is unlikely to overheat. As can be seen from the constant torque curve shown in Figure 11, an electric unit with a large torque inevitably has a larger current flowing through it (the distance from the origin of the dq-axis coordinate system to the operating point is longer). The heat generated by the electric unit tends to increase in proportion to the square of the current. Therefore, when the operating point is changed in an electric unit with a large torque, the increase in the amount of heat generated is large. From these points, it can be seen that T Ｘ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S Ｄ In the example, by actively increasing the d-axis current of the electric unit with a relatively large torque and causing the electric unit with a relatively large torque to generate heat preferentially, it is possible to increase the overall heat generation of the first electric unit 11 and the second electric unit 12 without causing the electric unit to overheat.

[0166] In the control method for the electric vehicle according to the above embodiment, the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) or less, and the representative temperature (θ ＩＮＶ－Ｘ ) is the temperature threshold (TH θ ) or less (state S Ｄ ), the d-axis current of both the first electric unit 11 and the second electric unit 12 is increased, and the increase in the d-axis current of the electric unit with a relatively large torque is made larger than the increase in the d-axis current of the electric unit with a relatively small torque.

[0167] In this way, T Ｘ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S ＤIn this case, it is desirable to increase the d-axis current of both the first electric unit 11 and the second electric unit 12, and to increase the d-axis current of the electric unit with a relatively large torque by a larger amount than the d-axis current of the electric unit with a relatively small torque. In this case, it is particularly easy to increase the total heat generation of the first electric unit 11 and the second electric unit 12. As a result, the warm-up of the on-board devices such as the battery 10 can be completed quickly.

[0168] In the control method for the electric vehicle according to the above embodiment, the torque of the electric unit having a relatively large torque is set as the representative torque (T Ｘ ＊ ) and the representative torque (T Ｘ ＊ ) is a predetermined torque threshold (TH Ｔ ), the temperature of the electric unit with a relatively large torque is set as the representative temperature (θ ＩＮＶ－Ｘ ) and the representative temperature (θ ＩＮＶ－Ｘ ) is a predetermined temperature threshold (TH θ ) and compare it with the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) and the representative temperature (θ ＩＮＶ－Ｘ ) is the temperature threshold (TH θ ) (state S Ｂ ), the d-axis current of the electric unit with a relatively large torque is maintained, and the d-axis current of the electric unit with a relatively small torque is increased.

[0169] In this way, T Ｘ ＊ >TH Ｔ and θ ＩＮＶ－Ｘ >TH θ State S Ｂ In this case, an electric unit with a relatively large torque already has a large current for torque output and the inverter temperature is high, so if the d-axis current is increased for warm-up control, it is likely to reach an overheating state. Ｘ ＊ >TH Ｔ and θ ＩＮＶ－Ｘ >TH θ State S ＢAs described above, the current of the electric unit with a relatively large torque is controlled by MTPA. ｄｑ－ＭＴＰＡ ＊ ) and increase only the d-axis current of the electric unit with a relatively small torque. Increasing only the d-axis current of the electric unit with a relatively small torque in this way makes it easier to increase the total heat generation of the first electric unit 11 and the second electric unit 12 without causing an overheating state.

[0170] In the control method for the electric vehicle according to the above embodiment, the torque of the electric unit having a relatively large torque is set as the representative torque (T Ｘ ＊ ) and the representative torque (T Ｘ ＊ ) is a predetermined torque threshold (TH Ｔ ), the temperature of the electric unit with a relatively large torque is set as the representative temperature (θ ＩＮＶ－Ｘ ) and the representative temperature (θ ＩＮＶ－Ｘ ) is a predetermined temperature threshold (TH θ ) and compare it with the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) and the representative temperature (θ ＩＮＶ－Ｘ ) is the temperature threshold (TH θ ) or less (state S Ａ ), or the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) or less, and the representative temperature (θ ＩＮＶ－Ｘ ) is the temperature threshold (TH θ ) (state S Ｃ ), the d-axis current of both the first electric unit 11 and the second electric unit 12 is increased, and the increase in the d-axis current of the electric unit with a relatively small torque is made larger than the increase in the d-axis current of the electric unit with a relatively large torque.

[0171] In this way, T Ｘ ＊ >TH Ｔ and θ ＩＮＶ－Ｘ ≦TH θ State S Ａ , or TＸ ＊ ≦TH Ｔ and θ ＩＮＶ－Ｘ >TH θ State S Ｃ In this case, it is preferable to increase the d-axis current of both the first electric unit 11 and the second electric unit 12, and to increase the d-axis current of the electric unit with a relatively small torque by a larger amount than the d-axis current of the electric unit with a relatively large torque. In this case, it is particularly easy to increase the total heat generation of the first electric unit 11 and the second electric unit 12 without causing an overheating state.

[0172] In the control method for an electric vehicle according to the above embodiment, the increase in the d-axis current of the electric unit having a relatively large torque is determined based on the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) or less. Ｃ ) than the representative torque (T Ｘ ＊ ) is the torque threshold (TH Ｔ ) Ａ ) are more common.

[0173] In this way, in the above embodiment, state S Ａ No.K α = k Ｄ , the state S Ｃ No.K α = k Ｂ By setting it to a value larger than (k Ｄ >k Ｂ ), state S Ａ The increase in the d-axis current of the electric unit with a relatively large torque in state S Ｃ As mentioned above, the amount of heat generated by an electric unit with a relatively large torque is more likely to increase when the operating point is changed along the constant torque curve. Ａ No.K α = k Ｄ , the state S Ｃ No.K α = k Ｂ If you set it to a value larger than (kＤ >k Ｂ ), the total heat generation amount of the first electric unit 11 and the second electric unit 12 is likely to increase to the limit within a range that does not result in an overheating state.

[0174] In the control method for an electric vehicle according to the first modified example, the temperatures of the first electric unit 11 and the second electric unit 12 are compared, and the d-axis current of the electric unit with a relatively lower temperature is made larger than the d-axis current of the electric unit with a relatively higher temperature.

[0175] In this way, even when the d-axis current of an electric unit with a relatively low temperature is made larger than the d-axis current of an electric unit with a relatively high temperature, the total heat generation amount of the first electric unit 11 and the second electric unit 12 can be increased without causing the unit to overheat.

[0176] In the control methods for electric vehicles according to the above-described embodiments and each of the modified examples, a d-axis current greater than the d-axis current when driven with the minimum current may be passed through one of the first electric unit 11 and the second electric unit 12, and a d-axis current equal to the d-axis current when driven with the minimum current may be passed through the other electric unit.

[0177] In this way, depending on the state of the first electric unit 11 and the second electric unit 12, one of the first electric unit 11 and the second electric unit 12 is substantially controlled by the MTPA control current (i ｄｑ－ＭＴＰＡ ＊ ), and the other is kept at a warm-up current (i ｄｑ－ｈｅａｔ ＊ In the above embodiment, it is also possible to drive the motor in the state S Ｂ In this case, either the first electric unit 11 or the second electric unit 12 is preferentially made to generate heat depending on the state of the first electric unit 11 or the second electric unit 12. Therefore, the first electric unit 11 and the second electric unit 12 are not allowed to overheat, and the total amount of heat generated by the first electric unit 11 and the second electric unit 12 can be increased. Therefore, the warm-up of the in-vehicle devices such as the battery 10 can be completed early.

[0178] In the control method for an electric vehicle according to the above embodiment and modification, a normal current command (i ｄｑ－ＭＴＰＡ ＊ ) and calculates the normal current command (i ｄｑ－ＭＴＰＡ ＊ ) to increase the d-axis current for warm-up (idq-heatMAP ＊ ) of the first electric unit 11 and the second electric unit 12. １ ＊ , T ２ ＊ ) and temperature (θ ＩＮＶ１ , θ ＩＮＶ２ ) based on the gain k １ , k ２ Then, the normal current command (i ｄｑ－ＭＴＰＡ ＊ ) and the warm-up current command (idq-heatMAP ＊ ) with gain k １ , k ２ By weighting and adding the current command (i ｄｑ－ｈｅａｔ ＊ ) is calculated.

[0179] In this way, the final warm-up current command i ｄｑ－ｈｅａｔ ＊ , the gain k １ , k ２ Basic warm-up current command idq-heatMAP using ＊ and MTPA current command i ｄｑ－ＭＴＰＡ ＊ When the calculation is performed by weighting the warm-up current command i ｄｑ－ｈｅａｔ ＊ The MTPA current command map 61 and the warm-up current command map 62 can be used in common regardless of the detailed combination of the states of the first electric unit 11 and the second electric unit 12. This makes it easy to accurately adjust the heat generation amount of the first electric unit 11 and the second electric unit 12 as a whole, within a range that does not result in an overheating state. Furthermore, the MTPA current command map 61 and the warm-up current command map 62 can be used in common regardless of the detailed combination of the states of the first electric unit 11 and the second electric unit 12. This makes it easy to easily and accurately increase the heat generation amount of the first electric unit 11 and the second electric unit 12 as a whole.

[0180] In the control method for an electric vehicle according to the second modification, the outputtable current I of the battery 10 is ｌｉｍ Based on this, the gain k １ , k ２ Correct the following.

[0181] In this way, the correction gain k １ ', k ２ ' is calculated and the warm-up current command i ｄｑ－ｈｅａｔ ＊ When the maximum output power P ＤＣ－ｌｉｍ Even if the warm-up current command i ｄｑ－ｈｅａｔ ＊ Therefore, the maximum output power P of the battery 10 is ＤＣ－ｌｉｍ Even if the maximum output power P ＤＣ－ｌｉｍ Within this range, the warm-up of the battery 10 is promoted to a substantially maximum extent.

[0182] The control device for an electric vehicle according to the above embodiment and each of the modified examples is a control device (controller 13) for an electric vehicle 100 having a first electric unit 11 and a second electric unit 12 that generate torque for traveling, and a battery 10 that supplies power to the first electric unit 11 and the second electric unit 12, and that warms up on-board equipment (e.g., the battery 10) using heat generated in the first electric unit 11 and the second electric unit 12. This control device (controller 13) includes a current command generator 41 that increases the d-axis current of the first electric unit 11, the second electric unit 12, or the first electric unit 11 and the second electric unit 12, to increase the heat generated by the entire first electric unit 11 and the second electric unit 12 when warming up of the on-board equipment (10) is required while the electric vehicle 100 is traveling. When the in-vehicle equipment (10) needs to be warmed up while the electric vehicle 100 is traveling, the current command generation unit 41 generates a current command (iｄｑ－ｈｅａｔ ＊ ) to generate the

[0183] In this way, when the electric vehicle 100 has the first electric unit 11 and the second electric unit 12, by preferentially causing one of the first electric unit 11 and the second electric unit 12 to generate heat depending on the state of the first electric unit 11 and the second electric unit 12, it is possible to prevent the first electric unit 11 and the second electric unit 12 from overheating and increase the overall heat generation amount of the first electric unit 11 and the second electric unit 12. This allows the warm-up of on-board equipment such as the battery 10 to be completed quickly.

[0184] The above describes embodiments and modifications of the present invention, but the configurations described in the above embodiments and modifications merely illustrate some of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

[0185] For example, in the above embodiment and each modified example, the on-board equipment to be warmed up is the battery 10, but this is not a limitation. Any on-board equipment that needs to be warmed up and that can transfer heat from the first electric unit 11 and the second electric unit 12 can be subject to warm-up control. Furthermore, heat transfer from the first electric unit 11 and the second electric unit 12 can be performed by methods other than using a cooling circuit.

Claims

1. A control method for an electric vehicle having a first electric unit and a second electric unit that generate torque for driving, and a battery that supplies power to the first electric unit and the second electric unit, in which on-board equipment is warmed up using heat generated in the first electric unit and the second electric unit, wherein when it becomes necessary to warm up the on-board equipment while the electric vehicle is driving, the control method increases the d-axis current of the first electric unit, the second electric unit, or the first electric unit and the second electric unit, thereby increasing the heat generated by the first electric unit and the second electric unit as a whole, and depending on the state of the first electric unit and the second electric unit, makes the d-axis current of one of the first electric unit and the second electric unit larger than the d-axis current of the other, thereby preferentially causing one of the first electric unit and the second electric unit to generate heat.

2. A control method for an electric vehicle according to claim 1, comprising: comparing the torque of the first electric unit and the torque of the second electric unit; and making the d-axis current of the electric unit with the relatively smaller torque larger than the d-axis current of the electric unit with the relatively larger torque.

3. A control method for an electric vehicle as claimed in claim 2, comprising: taking the torque of an electric unit with a relatively large torque as a representative torque, comparing the representative torque with a predetermined torque threshold; taking the temperature of the electric unit with a relatively large torque as a representative temperature, comparing the representative temperature with a predetermined temperature threshold; and, when the representative torque is equal to or less than the torque threshold and the representative temperature is equal to or less than the temperature threshold, exceptionally making the d-axis current of the electric unit with a relatively large torque larger than the d-axis current of the electric unit with a relatively small torque.

4. A control method for an electric vehicle as described in claim 3, wherein, when the representative torque is equal to or less than the torque threshold value and the representative temperature is equal to or less than the temperature threshold value, the d-axis current of both the first electric unit and the second electric unit is increased, and the increase in the d-axis current of the electric unit with a relatively large torque is made greater than the increase in the d-axis current of the electric unit with a relatively small torque.

5. A control method for an electric vehicle as claimed in claim 2, comprising: comparing the torque of an electric unit having a relatively large torque as a representative torque with a predetermined torque threshold value; comparing the temperature of an electric unit having a relatively large torque as a representative temperature with a predetermined temperature threshold value; and, if the representative torque is greater than the torque threshold value and the representative temperature is greater than the temperature threshold value, maintaining the d-axis current of the electric unit having a relatively large torque and increasing the d-axis current of the electric unit having a relatively small torque.

6. A control method for an electric vehicle as claimed in claim 2, comprising: taking the torque of an electric unit having a relatively large torque as a representative torque, comparing the representative torque with a predetermined torque threshold; taking the temperature of the electric unit having a relatively large torque as a representative temperature, comparing the representative temperature with a predetermined temperature threshold; and if the representative torque is larger than the torque threshold and the representative temperature is equal to or smaller than the temperature threshold, increasing the d-axis current of both the first electric unit and the second electric unit, and making the increase in the d-axis current of the electric unit having a relatively small torque larger than the increase in the d-axis current of the electric unit having a relatively large torque.

7. A control method for an electric vehicle as set forth in claim 6, wherein the increase in the d-axis current of an electric unit with a relatively large torque is more frequent in situations where the representative torque is greater than the torque threshold value than in situations where the representative torque is equal to or less than the torque threshold value.

8. A control method for an electric vehicle according to claim 1, comprising: comparing the temperatures of the first electric unit and the second electric unit; and making the d-axis current of the electric unit with a relatively lower temperature greater than the d-axis current of the electric unit with a relatively higher temperature.

9. A control method for an electric vehicle as described in claim 1, wherein a d-axis current greater than the d-axis current when driven with a minimum current is passed through one of the first electric unit and the second electric unit, and a d-axis current when driven with a minimum current is passed through the other electric unit.

10. A control method for an electric vehicle as claimed in claim 1, comprising: calculating a normal current command when driving with a minimum current; calculating a warm-up current command by increasing the d-axis current relative to said normal current command; setting a gain representing the priority of heat generation based on the torque and temperature of said first electric unit and said second electric unit; and calculating a final current command by weighting and adding said normal current command and said warm-up current command in accordance with said gain.

11. A method for controlling an electric vehicle according to claim 10, wherein the gain is corrected based on the available output current of the battery.

12. A control device for an electric vehicle having a first electric unit and a second electric unit that generate torque for driving, and a battery that supplies power to the first electric unit and the second electric unit, which warms up on-board equipment using heat generated in the first electric unit and the second electric unit, comprising a current command generation unit that increases the d-axis current of the first electric unit, the second electric unit, or the first electric unit and the second electric unit, to increase the heat generated by the first electric unit and the second electric unit as a whole, when it becomes necessary to warm up the on-board equipment while the electric vehicle is driving, and the current command generation unit generates a current command to preferentially heat one of the first electric unit and the second electric unit by making the d-axis current of one of the first electric unit and the second electric unit larger than the d-axis current of the other, depending on the state of the first electric unit and the second electric unit, when it becomes necessary to warm up the on-board equipment while the electric vehicle is driving.

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