JP2019037066A - Electric vehicle - Google Patents

Abstract

To reduce the number of signal lines wired from an outside of a cabin to an inside of the cabin.SOLUTION: An electric vehicle travels by power from a motor arranged on at least one of a front wheel and a rear wheel. The electric vehicle includes a power control unit arranged together with the motor on at least one of the front wheel and the rear wheel, and a control device which is arranged in a cabin and controls an inverter of the power control unit and operates a rotation speed of the motor by using a converted digital value. A resolver digital converter is mounted on the power control unit. The power control unit includes a first communication part which outputs the converted digital value to the control device by communication. The control device includes a second communication part which can communicate with the first communication part, and operates the rotation speed of the motor by using the converted digital value input in the second communication part through the communication. Thereby, the number of signal lines wired from an outside of the cabin to an inside of the cabin is reduced.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric vehicle, and more particularly, to an electric vehicle that travels with power from a motor disposed on at least one of a front wheel and a rear wheel.

  Conventionally, as this type of electric vehicle, a vehicle including four motors, four inverters, and a control device (control circuit) has been proposed (for example, see Patent Document 1). Four motors are disposed on each of the four wheels. Four inverters are arranged on each of the four wheels and drive each motor. The control device controls the four inverters. In this electric vehicle, the length of the power line connecting the inverter and the battery is shortened by arranging four batteries for supplying power to the four inverters on each of the four wheels.

JP 2017-22896 A

  Generally, a resolver for detecting the number of rotations of a motor is attached to a rotation shaft of the motor, and an resolver digital that inputs an excitation signal to the resolver and converts a Sin signal and a Cos signal from the resolver into digital values. The converter is mounted on the control device. When the control device is arranged in the vehicle interior, three signal lines (excitation signal, Sin signal, Cos signal) are required between the resolver and the resolver digital converter. In an electric vehicle in which four motors are arranged on each of four wheels, twelve signals are provided between four resolvers attached to the rotating shafts of the motors and a control device in the vehicle interior in which the resolver digital converter is mounted. It is necessary to wire a line, and the number of signal lines to be wired from the outside of the passenger compartment to the passenger compartment increases. In the vehicle interior, it is generally necessary to secure a space for the occupant to drive or sit, so the space for wiring the signal line is limited. For this reason, if the number of signal lines to be wired from outside the passenger compartment to the passenger compartment increases, wiring becomes difficult.

  The electric vehicle of the present invention is mainly intended to reduce the number of signal lines wired from outside the vehicle compartment to the vehicle interior.

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

The electric vehicle of the present invention is
An electric vehicle that travels with power from a motor disposed on at least one of a front wheel and a rear wheel,
A resolver attached to the rotating shaft of the motor;
A resolver digital converter which is connected to the resolver by a plurality of signal lines and converts signals from the resolver input from the plurality of signal lines into digital values;
A power control unit having an inverter for controlling the motor and disposed with the motor on at least one of the front wheel and the rear wheel;
A control device that is disposed in a vehicle interior, controls the inverter of the power control unit, and calculates the rotational speed of the motor using the converted digital value;
With
The resolver digital converter is mounted on the power control unit,
The power control unit includes a first communication unit that outputs the converted digital value to the control device by communication,
The control device includes a second communication unit capable of communicating with the first communication unit, and a rotational speed of the motor using the converted digital value input to the second communication unit via communication. ,
This is the gist.

  In the electric vehicle of the present invention, the resolver digital converter connected to the resolver by a plurality of signal lines is mounted in the power control unit. The power control unit includes a first communication unit that outputs the converted digital value to the control device by communication. The control device includes a second communication unit capable of communicating with the first communication unit, and calculates the rotation speed of the motor using the converted digital value input to the second communication unit via communication. Since the resolver digital converter is mounted on the power control unit, a plurality of signal lines connected to the resolver are wired to the power control unit. Since it is not necessary to wire these signal lines to the control device in the vehicle interior, the number of signal lines wired from outside the vehicle interior to the control device in the vehicle interior can be reduced. Here, the “communication” may be wired communication or wireless communication.

It is a block diagram which shows the outline of a structure of the electric vehicle 20 as one Example of this invention.

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

  FIG. 1 is a configuration diagram showing an outline of a configuration of an electric vehicle 20 as an embodiment of the present invention. As shown in the drawing, the electric vehicle 20 of the embodiment includes front wheel motors 22a and 22b, rear wheel motors 22c and 22d, resolvers 26a to 26d, PCUs 30a to 30d, a battery 40, and an electronic control unit (hereinafter referred to as an electronic control unit). , Referred to as “ECU”) 60.

  The front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are disposed near the front wheels 24a and 24b and the rear wheels 24c and 24d outside the vehicle compartment, respectively. The front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are configured as synchronous generator motors (so-called in-wheel motors) each having a rotor in which permanent magnets are embedded and a stator in which three-phase coils are wound. Power is output to the front wheels 24a and 24b and the rear wheels 24c and 24d.

  The resolvers 26a to 26d are attached to the rotation shafts of the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d, respectively. Resolvers 26a to 26d are mounted on rotors as magnetic bodies that rotate integrally with the rotors (rotating shafts) of front wheel motors 22a and 22b and rear wheel motors 22c and 22d, and RDCs 34a to 34d of PCUs 30a to 30d. An excitation coil to which an excitation signal (an AC current having a constant frequency) as an analog signal is applied from an oscillation circuit (not shown) and an output coil that is electrically shifted by 90 degrees (so that the phase difference becomes 90 degrees) are incorporated. And a stator as a magnetic body. The output signal of the output coil is an analog signal generated with a change in the gap between the rotor and the stator caused by the rotation of the elliptical rotor, and is a sine signal having a sine wave shape and a cosine wave shape when the peak value is complemented. , Cos signals.

  The PCUs 30a to 30d include inverters 32a to 32d, resolver digital converters (hereinafter referred to as “RDC”) 34a to 34d, and communication units 36a to 36d.

  The inverters 32a to 32d drive the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d, respectively. Inverters 32a to 32d are connected to battery 40 via a power line. The front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are rotationally driven by the ECU 60 by switching control of a plurality of switching elements (not shown) of the inverters 32a to 32d.

  Three RDCs 34a to 34d are connected to each of the resolvers 26a to 26d by a total of twelve analog signal lines La1 to La12. The RDCs 34a to 34d output excitation signals to be applied to the excitation coils of the resolvers 26a to 26d via analog signal lines La1, La4, La7, and La10. The RDCs 34a to 34d input output signals (Sin signal, Cos signal) from the resolvers 26a to 26d via the analog signal lines La2, La3, La5, La6, La8, La9, La11, La12, and the input Sin signal. The Cos signal is converted into a digital value, and these digital values are output to the communication units 36a to 36d.

  The communication units 36a to 36d are connected to the ECU 60 by four digital signal lines Ld1 to Ld4, and exchange various signals with the ECU 60 in the vehicle interior 70 by high-speed digital communication via the digital signal lines Ld1 to Ld4. ing. Here, “digital communication” may be serial communication or parallel communication.

  The battery 40 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and exchanges electric power with the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d via the inverters 32a to 32d.

  The ECU 60 is disposed in the passenger compartment 70 and is configured as a microprocessor centered on a CPU (not shown). In addition to the CPU, a ROM that stores a processing program and a RAM that temporarily stores data. , A communication unit 62 that performs digital communication with the communication units 36a to 36d, and an input / output port. From ECU 60, a control signal for controlling inverters 32a to 32d is output from the output port.

  From the ECU 60, various control signals necessary for controlling the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are output via an output port.

  The communication unit 62 exchanges various data and signals with the communication units 36a to 36d of the PCUs 30a to 30d via the digital signal lines Ld1 to Ld4. The communication unit 62 includes digital values of Sin signals and Cos signals from the RDCs 34a to 34d, sensor values from sensors that detect currents of the front wheel motors 22a and 22b, and rear wheel motors 22c and 22d. Data necessary for controlling the motors for the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d is input via the communication units 36a to 36d.

  In the electric vehicle 20 configured in this manner, the ECU 60 uses the Sin signal and the digital value of the Cos signal input from the RDCs 34a to 34d via the communication unit 62, and the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d. The rotation speed is calculated. Using the calculated rotational speeds of the front wheel motors 22a and 22b and rear wheel motors 22c and 22d and various sensor values that are input, the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d have their respective driving forces. Switching control of the plurality of switching elements of the inverters 32a to 32d is performed so as to be driven by the commands Fma * to Fmd *. Thus, the front wheels 24a and 24b and the rear wheels 24c and 24d are driven by the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d to travel.

  In the electric vehicle 20 of the embodiment, the ECU 60 uses the digital values of the Sin signal and the Cos signal input from the RDCs 34a to 34d via the communication unit 62 to control the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d. The rotation speed is calculated.

  In the electric vehicle 20 of the embodiment, the resolvers 26a to 26d and the RDCs 34a to 34d are connected by twelve analog signal lines La1 to La12. If the RDCs 34a to 34d are disposed in the ECU 60 in the passenger compartment 70, twelve analog signal lines La1 to La12 are wired from the resolvers 26a to 26d into the passenger compartment 70. In the embodiment, by arranging the RDCs 34a to 34d in the PCUs 30a to 30d, it is not necessary to wire the 12 analog signal lines La1 to La12 from the resolvers 26a to 26d to the passenger compartment, and the communication units 36a to 36d and the ECU 60 of the PCU 30a. The communication unit 62 may be connected by four digital signal lines Ld1 to Ld4. Therefore, the number of signal lines wired from the outside of the passenger compartment 70 to the inside of the passenger compartment 70 can be reduced as compared with the case where the RDCs 34 a to 34 d are arranged in the ECU 60.

  Since the resolvers 26a to 26d and the RDCs 34a to 34d are connected by 12 analog signal lines La1 to La12, the RDCs 34a to 34d are mounted on the ECU 60, and the 12 analog signals are connected between the resolvers 26a to 26d and the ECU 60. The wiring lengths of the analog signal lines La1 to La12 can be made shorter than those connected by the signal lines La1 to La12. Thereby, a wiring delay can be reduced between the resolvers 26a to 26d and the RDCs 34a to 34d.

  Further, the digital values calculated by the RDCs 34a to 34d of the PCUs 30a to 30d are converted into digital signal lines Ld1 to sensor values from sensors for detecting the currents of the respective phases of the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d. Since the digital signal is output to the communication unit 62 of the ECU 60 by high-speed digital communication via Ld4, the digital value calculated by the PDCs 34a to 34d can be obtained even when a communication delay time occurs due to retransmission due to a communication frame error or the like in digital communication. Since the acquisition timing and the acquisition timing of the sensor values from the sensors for detecting the currents of the respective phases of the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are suppressed from being greatly different from each other, the communication delay time is controlled by digital communication. Even when this occurs, front wheel motors 22a and 22b, rear wheel motor 22 , It is possible to suppress a decrease in the controllability of 22d.

  According to the electric vehicle 20 of the embodiment described above, the RDCs 34a to 34d are mounted on the PCUs 30a to 30d, the communication units 36a to 36d are provided in the PCUs 30a to 30d, and the ECU 60 can communicate with the communication units 36a to 36d. A signal that is wired from the outside of the passenger compartment 70 to the inside of the passenger compartment 70 by calculating the rotational speed of the motor using the converted digital value input to the communication portion 62 via the communication by the ECU 60. The number of lines can be reduced.

  In the electric vehicle 20 of the embodiment, the communication units 36a to 36d and the communication unit 62 are connected by wires (digital signal lines Ld1 to Ld4), but do not have the digital signal lines Ld1 to Ld4. Data and signals may be exchanged between the communication units 36a to 36d and the communication unit 62 by wireless communication.

  In the electric vehicle 20 according to the embodiment, communication is performed between the communication units 36a to 36d and the communication unit 62, but the ECU 60 includes four communication units 62, and each of the four communication units 62 communicates individually. It does not matter as a thing to do.

  In the electric vehicle 20 of the embodiment, front wheel motors 22a and 22b and rear wheel motors 22c and 22d are attached to the front wheels 24a and 24b and the rear wheels 24c and 24d, and the front wheel motors 22a and 22b and the rear wheel motors 22c and 22d are attached. From the front wheels 24a and 24b and the rear wheels 24c and 24d. However, the present invention is applied to a vehicle in which two motors are attached only to either the front wheels 24a, 24b or the rear wheels 24c, 24d and the motive power is output from the two motors to the front wheels 24a, 24b or the rear wheels 24c, 24d. It doesn't matter.

  In the electric vehicle 20 of the embodiment, the front wheels 24a and 24b and the rear wheels 24c and 24d are provided with four wheels, but the number of wheels is not limited to four. You may apply to a car. For example, when one front wheel and two rear wheels are used, a motor and resolver may be disposed only on the front wheel, and a PCU equipped with RDC may be disposed only on the front wheel.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the front wheel motor 22a corresponds to a “motor”, the resolver 26a corresponds to a “resolver”, the resolver digital converter 34a corresponds to “RDC”, the PCU 30a corresponds to a “power control unit”, and the ECU 60 Corresponds to a “control device”.

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

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

  The present invention can be used in the manufacturing industry of electric vehicles.

  20 electric vehicle, 22a, 22b front wheel motor, 22c, 22d rear wheel motor, 24a, 24b front wheel, 24c, 24d rear wheel, 26a-26d resolver, 30a-30d power control unit (PCU), 32a-32d inverter, 34a-34d Resolver digital converter (RDC), 36a-36d communication part, 40 battery, 60 electronic control unit (ECU), 62 communication part, 70 compartment, La1-La12 analog signal line, Ld1-Ld4 digital signal line.

Claims (1)

An electric vehicle that travels with power from a motor disposed on at least one of a front wheel and a rear wheel,
A resolver attached to the rotating shaft of the motor;
A resolver digital converter which is connected to the resolver by a plurality of signal lines and converts signals from the resolver input from the plurality of signal lines into digital values;
A power control unit having an inverter for controlling the motor and disposed with the motor on at least one of the front wheel and the rear wheel;
A control device that is disposed in a vehicle interior, controls the inverter of the power control unit, and calculates the rotational speed of the motor using the converted digital value;
With
The resolver digital converter is mounted on the power control unit,
The power control unit includes a first communication unit that outputs the converted digital value to the control device by communication,
The control device includes a second communication unit capable of communicating with the first communication unit, and a rotational speed of the motor using the converted digital value input to the second communication unit via communication. ,
Electric vehicle.

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