阅读说明：本技术 马达控制装置、操舵致动器用马达控制装置、操舵致动器系统 (Motor control device, motor control device for steering actuator, and steering actuator system ) 是由 今里谅 梅本贵史 横塚拓也 于 2020-03-23 设计创作，主要内容包括：提供马达控制装置、操舵致动器用马达控制装置、操舵致动器系统。本发明的一个方式的马达控制装置对具有两个系统的角度传感器的三相马达进行驱动,其中,两个系统的角度传感器由第1角度传感器和第2角度传感器构成。马达控制装置具有控制部,该控制部对两个系统的角度传感器分别输出励磁信号,该两个系统的角度传感器将各自感应出的检测信号输入给该控制部,第1角度传感器的第1励磁信号的频率与第2角度传感器的第2励磁信号的频率不同。(A motor control device, a motor control device for a steering actuator, and a steering actuator system are provided. A motor control device according to an aspect of the present invention drives a three-phase motor including two systems of angle sensors, wherein the two systems of angle sensors include a 1 st angle sensor and a 2 nd angle sensor. The motor control device includes a control unit that outputs excitation signals to two systems of angle sensors, respectively, and the two systems of angle sensors input detection signals sensed by the two systems of angle sensors to the control unit, wherein a frequency of a 1 st excitation signal of a 1 st angle sensor is different from a frequency of a 2 nd excitation signal of a 2 nd angle sensor.)

1. A motor control device for driving a three-phase motor having two systems of angle sensors,

the angle sensors of the two systems are composed of a 1 st angle sensor and a 2 nd angle sensor,

the motor control device includes a control unit that outputs excitation signals to the angle sensors of the two systems, respectively, and inputs detection signals sensed by the angle sensors of the two systems to the control unit,

the frequency of the 1 st excitation signal of the 1 st angle sensor is different from the frequency of the 2 nd excitation signal of the 2 nd angle sensor.

2. The motor control apparatus according to claim 1,

the three-phase motor is composed of two systems of winding groups,

the motor control device includes:

inverter circuits of two systems that drive the winding groups of the two systems for each system; and

control circuits of two systems that control the inverter circuits of the two systems per system,

the control circuits of the two systems are composed of a 1 st control circuit and a 2 nd control circuit, and each system is provided with a power supply part for generating an internal power supply from an external constant power supply,

the 1 st control part of the 1 st control circuit outputs the 1 st excitation signal,

the 2 nd control unit of the 2 nd control circuit outputs the 2 nd excitation signal.

3. The motor control apparatus according to claim 1,

inducing a 1 st detection signal from the 1 st excitation signal,

inducing a 2 nd detection signal from the 2 nd excitation signal,

the 1 st detection signal and the 2 nd detection signal are subjected to filtering processing by the control unit.

4. The motor control apparatus according to claim 3,

the filtering is band-pass filtering and band-stop filtering.

5. A motor control device for a steering actuator, which employs the motor control device according to any one of claims 1 to 4 as a motor control device for a steering actuator that automates steering operation of a vehicle.

6. A steering actuator system having the motor control device for a steering actuator according to claim 5.

Technical Field

The present invention relates to a motor control device, a motor control device for a steering actuator, and a steering actuator system.

Background

Conventionally, as a steering system for a large vehicle, there is an electric power steering apparatus that controls a hydraulic pressure of a hydraulic power steering apparatus by a motor. In recent years, automatic driving and automatic steering of a large vehicle are desired. Therefore, the steering actuator system performs automatic steering by operating the electric hydraulic power steering apparatus using a steering actuator (motor). Since it is necessary to improve safety against a failure of the steering actuator system, a motor control device for controlling the steering actuator (motor) needs to be made redundant. The motor control device detects and controls the angle of the motor rotation shaft. As a redundant angle sensor, two systems of angle sensors in which a resolver is disposed in close proximity are known. (patent document 1)

Patent document 1: japanese laid-open patent publication No. 2009-210281

The motor control device of the steering actuator system receives an angle signal from an angle sensor of a motor rotation shaft and executes motor control. Therefore, if the angle sensor fails, the angle signal cannot be acquired, and there is a possibility that the motor control is hindered, and therefore, it is necessary to make the angle sensor redundant. In the angle sensor of patent document 1, two resolvers are disposed close to each other, and high angle detection accuracy can be maintained even if two excitation signals that are excited asynchronously with each other magnetically interfere with each other.

Disclosure of Invention

A motor control device according to an aspect of the present invention drives a three-phase motor including two systems of angle sensors, wherein the two systems of angle sensors include a 1 st angle sensor and a 2 nd angle sensor. The motor control device includes a control unit that outputs excitation signals to two systems of angle sensors, respectively, and the two systems of angle sensors input detection signals sensed by the two systems of angle sensors to the control unit, wherein a frequency of a 1 st excitation signal of a 1 st angle sensor is different from a frequency of a 2 nd excitation signal of a 2 nd angle sensor.

A motor control device for a steering actuator according to an aspect of the present invention employs the above-described motor control device as a motor control device for a steering actuator that automates steering operation of a vehicle.

A steering actuator system according to an aspect of the present invention includes the above-described motor control device for a steering actuator.

According to the exemplary embodiment of the present invention, in the motor control device, since the frequencies of the excitation signals of the angle sensors of the two systems are different from each other, even if the respective excitation signals interfere as noise, the angle can be easily detected from the respective detection signals.

Drawings

Fig. 1 is a diagram showing an overall configuration of a steering actuator system including a motor control device for a steering actuator according to an embodiment of the present invention.

Fig. 2 is a diagram showing a detailed configuration of the motor control device for the steering actuator shown in fig. 1.

Fig. 3 is a diagram showing a schematic configuration of two systems of angle sensors.

Fig. 4A is a diagram showing an excitation signal and a detection signal of the angle sensor of the 1 st system.

Fig. 4B is a diagram showing an excitation signal and a detection signal of the angle sensor of the 2 nd system.

Fig. 5 is a diagram showing a schematic flowchart of the angle calculation of the motor control device.

Fig. 6A is a diagram showing a result of simulating an angle calculation error in the case where the motor control device does not perform the filtering process.

Fig. 6B is a diagram showing a result of simulating an angle calculation error in the case where the motor control device performs the band-pass filtering process.

Fig. 6C is a graph showing a result of simulating an angle calculation error in the case where the motor control device performs band-pass filtering and then band-stop filtering.

Description of the reference symbols

1: a motor control device; 1 a: a motor control device (1 st system); 1 b: a motor control device (2 nd system); 2: a steering wheel; 3: a rotating shaft; 7: a rack shaft; 8 a: rotating the valve; 8 b: a power cylinder; 9. 9a, 9 b: a torque sensor; 10: a steering actuator system; 11 a: angle sensor (system 1); 11 b: angle sensor (system 2); 12a, 12 b: a control unit (CPU); 13a, 13 b: an inverter control unit; 14a, 14 b: an inverter circuit; 15. 15a, 15 b: a steering actuator (motor); 16a, 16 b: a filter; 17a, 17 b: a power supply relay; 18a, 18 b: inputting an I/F; 19a, 19 b: CANI/F; 27: a CAN signal line; 27 a: a CAN-H line; 27 b: a CAN-L line; 31: an ignition switch (IG-SW); BT: a battery.

Detailed Description

Hereinafter, embodiments of the motor control device, the motor control device for a steering actuator having the motor control device, and the steering actuator system having the motor control device for a steering actuator according to the present disclosure will be described in detail with reference to the drawings. However, in order to avoid unnecessarily long descriptions below, it may be easy for those skilled in the art to understand that an excessively detailed description may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of substantially the same structures may be omitted.

Fig. 1 is a diagram showing an example of the overall configuration of a steering actuator system 10. The steering actuator system 10 is a device for assisting a steering operation of a driver in a transportation facility such as a large vehicle. The steering actuator system 10 includes a battery BT as a power supply source, a motor Control device 1 as an Electronic Control Unit (ECU), a steering wheel 2 as a steering member, a rotary shaft 3 connected to the steering wheel, a pinion gear 6, a rack shaft 7, a rotary valve 8a that adjusts hydraulic pressure from a hydraulic pressure source (not shown), a power cylinder 8b that drives the rack shaft by hydraulic pressure, and the like.

The rotary shaft 3 is engaged with a pinion 6 provided at a front end thereof. The rotational motion of the rotary shaft 3 is converted into the linear motion of the rack shaft 7 by the pinion 6. The hydraulic pressure sent from the rotary valve 8a is transmitted to the power cylinder 8b as an output for assisting the rotation of the rotary shaft 3, and the piston of the power cylinder 8b is operated to be converted into the linear motion of the rack shaft 7. The pair of wheels 5a and 5b provided at both ends of the rack shaft 7 are steered at an angle corresponding to the displacement amount of the rack shaft 7.

A motor 15 having an angle sensor for a steering actuator is coaxially provided on the rotary shaft 3. The motor control device 1 obtains a steering angle of the rotary shaft 3 from an angle of the rotary shaft of the motor acquired by the angle sensor, generates a motor drive signal so that the steering angle becomes an instruction steering angle received from an Advanced Driver-Assistance Systems-electronic control Unit (not shown), and outputs the signal to the motor 15. The ADAS-ECU instructs the steering angle regardless of the steering operation of the driver, and the steering actuator system performs automatic steering.

A torque sensor 9 for detecting a steering torque when the steering wheel 2 is operated is provided on the rotary shaft 3, and the detected steering torque is transmitted to the motor control device 1. The motor control device 1 detects the intervention of steering of the steering wheel by the driver from the steering torque acquired by the torque sensor 9, generates an attenuation or stop signal of the motor drive signal, and outputs the signal to the electric motor 15. The automatic steering by the steering actuator system can be stopped and the manual steering can be performed by the intervention of the steering operation by the driver.

Next, the motor control device of the present embodiment will be explained. As shown in fig. 2, the motor control device of the present embodiment has a redundant configuration including a plurality of motor control systems having the same components except for predetermined portions. Here, a motor control device having a redundant configuration including two systems will be described as an example, but the present invention may be further extended to a redundant configuration including a plurality of systems, such as three systems and four systems.

The motor control device of the present embodiment is constituted by motor control devices 1a, 1b, and the motor control devices 1a, 1b are constituted by two systems independent of each other having control units (CPUs) 12a, 12b, respectively. The motor control devices 1a, 1b adopt a dual inverter structure having: an electric motor 15 having two sets of three-phase windings (Ua, Va, Wa)15a and three-phase windings (Ub, Vb, Wb)15 b; and two sets of inverter circuits 14a, 14b that supply drive currents to the two sets of three-phase windings, respectively. The electric motor 15 is, for example, a three-phase brushless DC motor.

In the following description, a component including the motor control device 1a and the three-phase winding 15a is referred to as a 1 st system, and a component including the motor control device 1b and the three-phase winding 15b is referred to as a 2 nd system.

The motor control device 1a constituting the 1 st system includes: a control unit (CPU)12a, which is responsible for controlling the entire motor control device 1a and is constituted by a microprocessor, for example; an inverter control unit 13a that generates a motor drive signal based on a control signal from the CPU12 a and functions as an FET drive circuit; and an inverter circuit 14a, which is a motor driving unit that supplies a driving current to the three-phase windings (Ua, Va, Wa)15a of the electric motor 15.

The motor control device 1b constituting the 2 nd system includes, similarly to the motor control device 1 a: a control unit (CPU)12b that controls the entire motor control device 1 b; an inverter control unit 13b that generates a motor drive signal based on a control signal from the CPU12b and functions as an FET drive circuit; and an inverter circuit 14b that supplies a predetermined drive current to the three-phase windings (Ub, Vb, Wb)15b of the electric motor 15.

The inverter circuit 14a is supplied with power for driving the motor from the external battery BT via the filter 16a and the power supply relay 17a, and the inverter circuit 14b is supplied with power for driving the motor from the external battery BT via the filter 16b and the power supply relay 17 b. The filters 16a and 16b may be included in the inverter circuits 14a and 14b, respectively.

The filters 16a and 16b are composed of an electrolytic capacitor and a coil, not shown, and absorb noise and the like included in the power supply to smooth the power supply voltage. The power supply relays 17a and 17b are configured to be able to cut off power from the battery BT, and are configured by, for example, a mechanical relay or a semiconductor relay.

The inverter circuit 14a is a FET bridge circuit including semiconductor switching elements (FETs) corresponding to the three-phase windings (Ua, Va, Wa)15a of the electric motor 15. Similarly, the inverter circuit 14b is a FET bridge circuit including semiconductor switching elements (FETs) corresponding to the three-phase windings (Ub, Vb, Wb)15b of the electric motor 15.

These switching elements (FETs) are also called power elements, and for example, semiconductor switching elements such as MOSFETs (Metal-oxide semiconductor Field-Effect transistors) and IGBTs (Insulated Gate Bipolar transistors) are used.

The ignition switch (IG-SW)31 has one end connected to the battery BT and the other end connected to the IG voltage detection units 24a and 24 b. The IG voltage detection units 24a and 24b AD-convert an Ignition (IG) voltage value, and input the converted digital voltage value to the CPUs 12a and 12b as an actual voltage value of the IG voltage. The IG voltage detector may be built in the CPU.

The power supply units 20a and 20B convert the battery voltage + B supplied from the battery BT into a predetermined voltage (for example, a voltage of a logic level) and supply the voltage to operation power supplies of the control units (CPUs) 12a and 12B, the inverter control units 13a and 13B, and the like.

Switches 21a and 21b linked to the operation of an ignition switch (IG-SW)31 are provided on the paths between the power supply units 20a and 20b and the battery BT. When the ignition switch (IG-SW)31 is off, the switches 21a and 21b are also off, and when the ignition switch (IG-SW)31 is on, the switches 21a and 21b are also on. By having the switches 21a, 21b, it is possible to reduce dark current of the motor control devices 1a, 1b when the ignition switch (IG-SW)31 is turned off. By reducing the dark current, battery depletion can be prevented.

The CPUs 12a and 12b of the motor control devices 1a and 1b are configured to be able to perform mutual communication in real time. The motor control devices 1a and 1b perform data communication with another control unit (ECU) by a CAN protocol via CAN signal lines (CAN communication buses) 27H and 27L and CAN I/ fs 19a and 19b connected to a vehicle-mounted network (CAN) that transmits and receives various information of the vehicle.

The CAN signal lines 27H and 27L are two-wire communication lines each composed of a CAN-H line 27Ha and a CAN-L line 27La constituting the 1 st system and a CAN-H line 27Hb and a CAN-L line 27Lb constituting the 2 nd system.

The electric motor 15 is mounted with angle sensors (resolvers) 11a and 11b for detecting a rotational position of a rotor of the motor. The output signal from the angle sensor (resolver) 11a is sent as rotation information to the CPU12 a via the input I/F18 a, and the output signal from the angle sensor (resolver) 11b is sent to the CPU12b via the input I/F18 b.

By providing redundancy in the 1 st system 1a and the 2 nd system 1b including the power supply units 20a and 20b, the CPUs 12a and 12b, the inverter circuits 14a and 14b, and the like, it is possible to provide a highly reliable motor control device with high safety against failure.

Fig. 3 is a diagram showing a schematic configuration of two systems of angle sensors (resolvers) 11a, 11 b. Two systems of excitation coils and detection coils are incorporated for one resolver rotor, and a redundant configuration is obtained. To distinguish the excitation signals from each other, different excitation signals are input to the respective systems, an excitation signal of, for example, 10kHz is input to the angle sensor of the 1 st system, and an excitation signal of, for example, 5kHz is input to the angle sensor of the 2 nd system.

Since the angle sensors (resolvers) 11a and 11b that are designed to be redundant are disposed close to each other, the excitation signal of the 1 st system may cause noise that induces the detection coil of the 2 nd system, and the excitation signal of the 2 nd system may cause noise that induces the detection coil of the 1 st system.

Fig. 4A is a diagram showing a relationship between an excitation signal and a detection signal of the angle sensor (resolver) of the 1 st system. In the 1 st system, with respect to the 1 st excitation signal R1_ a, there are a sine wave S2_ a and a cosine wave S1_ a as the 1 st detection signal. The sine wave S2_ a in the 1 st detection signal is mixed with a signal induced by the 2 nd excitation signal R1_ B of the 2 nd system as noise, and the sine wave is broken.

Fig. 4B is a diagram showing a relationship between an excitation signal and a detection signal of the angle sensor (resolver) of the 2 nd system. In the 2 nd system, with respect to the 2 nd excitation signal R1_ B, there are a sine wave S2_ B and a cosine wave S1_ B as the 2 nd detection signal. The sine wave S2_ B in the 2 nd detection signal is mixed with a signal induced by the 1 st excitation signal R1_ a of the 1 st system as noise, and the sine wave is broken.

Since the detection signal of the resolver is derived from the values of the sine wave and the cosine wave of the rotor angle, the amplitude ratio of the signal matches the tangent value of the rotor angle. Therefore, the rotor angle Θ can be found by an arctangent trigonometric function of dividing the amplitude Vs of the sine signal by the amplitude Vc of the cosine signal.

< equation 1>

θ＝tan^-1(sinθ/cosθ)＝tan^-1(Vs/Vc)

Fig. 5 shows a schematic flowchart of the angle calculation of the motor control device. In the present embodiment, as the noise removal filter, band-stop filtering (BSF) is implemented after band-pass filtering (BPF).

It is assumed that 10kHz is input as the 1 st excitation signal. First, in step ST1, band-pass filtering of 10kHz is performed as the 1 ST detection signal. Next, in step ST2, band-stop filtering of 5kHz is applied to the band-pass filtered 1 ST detection signal. This is to remove a noise component induced by 5kHz of the 2 nd excitation signal. Next, in step ST3, the rotation angle of the 1 ST angle sensor is obtained from the 1 ST detection signal after band rejection filtering by equation 1.

Similarly, it is assumed that 5kHz is input as the 2 nd excitation signal. First, in step ST1, band-pass filtering of 5kHz is performed as the 2 nd detection signal. Next, in step ST2, band-stop filtering of 10kHz is applied to the band-pass filtered 2 nd detection signal. This is to remove a noise signal induced by 10kHz of the 1 st excitation signal. Next, in step ST3, the rotation angle of the 2 nd angle sensor is obtained from the 2 nd detection signal after band rejection filtering by equation 1.

It is well known that the band-pass filtering BPF can be implemented by the following equation.

< equation 2>

In the formula 2,. omega₀Is the peak gain angular frequency and Q is sharpness.

For example, when a 10kHz band is to be passed as the detection signal, ω is used by assuming that the peak gain frequency fp is 10kHz₀＝(2πfp)＝62831.853，Q＝10，ω₀ ²3947841751.4136, a band pass filtered BPF can be implemented.

For example, when a 5kHz band is to be passed as the detection signal, the peak gain fp is assumed to be 5kHz, and ω is used₀＝(2πfp)＝31415.9265，Q＝10，ω₀ ²986960437.8534, a band pass filtered BPF can be implemented.

It is well known that the band-stop filtering BSF can be implemented by the following equation.

< equation 3>

In the formula 3,. omega₀Is the cut-off angular frequency and Q is sharpness.

For example, when the 10kHz band is to be cut off as the detection signal, the cutoff frequency fc is 10kHz, and ω is used₀＝(2πfc)＝62831.853，Q＝10，ω₀ ²3947841751.4136, a band-stop filtering BSP can be achieved.

For example, when the 5kHz band is to be cut off as the detection signal, the cutoff frequency fc is assumed to be 5kHz, and ω is used₀＝(2πfc)＝31415.9265，Q＝10，ω₀ ²986960437.8534, a band-stop filtering BSP can be implemented.

The band-pass filter and the band-stop filter may be formed by hardware circuits, but since the filter characteristics change depending on the temperature characteristics of circuit components such as capacitors and component variations, the effect is good when the filter is formed by software.

Fig. 6A is a diagram showing a result of simulating an angle calculation error in the case where the motor control device does not perform the filtering process. Fig. 6B is a graph showing a result of simulating an angle calculation error in the case where the motor control device performs the band-pass filtering process. Fig. 6C is a graph showing a result of simulating an angle calculation error in the case where the motor control device performs the band elimination filtering process after the band pass filtering. Here, the error in the case of performing angle calculation without filtering the 1 st detection signal is in the range of about +2degE to-4 degE with respect to the ideal angle, and the error in the case of performing angle calculation using the 1 st detection signal after the band-pass filtering BPF is about ± 0.2 degE. Further, the error in the case of performing angle calculation using the 1 st detection signal obtained by applying the band-elimination filter BSF to the 1 st detection signal after the band-pass filter BPF is ± 0.01degE, and it can be confirmed that the accuracy of angle calculation is improved by applying the band-pass filter BPF and the band-elimination filter BSF. By performing appropriate filtering processing on the detection signal, the angle calculation accuracy can be improved.

As a motor control device for a steering actuator system, in order to perform automatic steering, it is effective that the angle error is less than ± 1degE because the higher the accuracy of the steering angle is, the better. This can improve the control accuracy of the motor control device for a steering actuator.

Further, by using the steering actuator system including the motor control device for a steering actuator, it is possible to provide a steering actuator system capable of realizing high-precision control, and it is possible to provide an automatic steering system capable of realizing high-precision control.

The steering actuator system 10 is configured to include the motor control device 1, but is not limited to this. The motor control device 1 may be a control device that controls other components in a vehicle or the like.

In the present embodiment, the 1 st system 1a and the 2 nd system 1b may be formed in one circuit board or may be formed in different circuit boards.