JP2022083159A - Motor control device - Google Patents

Abstract

To provide a motor control device configured to control driving of a multi-phase motor and a DC motor which moves a mobile of a section movement actuator, the motor control device being capable of determining an end abutment of the section movement actuator while downsizing a power conversion circuit.SOLUTION: A first circuit 68 electrifies a multi-phase motor 800. A second circuit 67 electrifies a DC motor 720 which outputs a torque so as to move a mobile in a section movement actuator configured to move the mobile in a predetermined section. When a pair of high potential side and low potential side switching elements connected in series in the first circuit 68 and the second circuit 67 is defined as a leg, the first circuit 68 and the second circuit 67 form integrated power conversion circuits 60 sharing one leg. A control unit 400 includes an end abutment determination unit 50 for determining an end abutment that the mobile of the section movement actuator is abutted against an end of the section when electrifying the DC motor 720.SELECTED DRAWING: Figure 6

Description

The present invention relates to a motor control device.

Conventionally, a motor control device that shares a circuit for driving a multi-phase motor and a DC motor is known.

For example, the motor control device disclosed in Patent Document 1 drives a three-phase AC motor and two DC motors by one three-phase inverter drive circuit. Specifically, this motor control device is used in a vehicle steering device to drive a three-phase motor for electric power steering (EPS), a direct current motor for a tilt actuator, and a direct current motor for a telescopic actuator. By sharing the power converters of the three-phase motor and the DC motor, the power converter is downsized.

Japanese Patent No. 5614588

For example, a tilt actuator or a telescopic actuator of a steering device displaces a range from an ascending limit to a descending limit or a forward limit to a backward limit by moving a moving body in a predetermined section. In the present specification, actuators configured so that a moving body can move in a predetermined section are collectively referred to as "section moving actuators". Further, the fact that the moving body of the section moving actuator comes into contact with the end of the section is called "end contact". Here, the word "contact" is used to mean the present perfect tense, that is, the place where the contact has just been made, not the past tense.

The DC motor outputs torque so as to move the moving body in the section moving actuator. Since the speed of the moving body becomes zero in the end contact state, the induced voltage of the DC motor becomes zero and an overcurrent occurs. In an open-controlled DC motor, it is not possible to detect the current and control the output, and there is a risk that the mechanism of the section moving actuator will be damaged due to the generation of excessive thrust. If a position sensor is to be mounted in order to prevent this, problems such as an increase in the number of connector pins for receiving the sensor signal and an increase in cost due to an increase in parts will occur. No mention is made in Patent Document 1 regarding a method for controlling a DC motor in consideration of such an end pad.

The present invention has been created in view of these points, and an object of the present invention is to convert power in a multiphase motor and a motor control device for controlling the drive of a DC motor for moving a moving body of a section moving actuator. It is an object of the present invention to provide a motor control device capable of determining the end contact of a section moving actuator while downsizing the circuit.

The motor control device of the present invention includes a first circuit (68, 681, 682), a second circuit (67), and a control unit (400). The first circuit is a power conversion circuit that energizes the polyphase motor (800). The second circuit is a power conversion circuit that energizes a DC motor (720, 730). This DC motor outputs torque so as to move the moving body in the section moving actuators (20, 30) configured so that the moving body (24) can move in a predetermined section. The control unit operates the first circuit and the second circuit to control the operation of the polyphase motor and the DC motor.

The first circuit and the second circuit are provided in the same housing (600). A set of high-potential side and low-potential side switching elements connected in series in the first circuit and the second circuit is used as a leg. One terminal of the DC motor is connected to the one-phase phase current path of the polyphase motor and the other terminal of the DC motor is connected between a set of high and low potential side switching elements in the second circuit. As a result, the first circuit and the second circuit form an "integrated power conversion circuit (60)" that shares one leg.

The control unit has an end-hit determination unit (50) that determines "end-hit" that a moving body of the section-moving actuator has come into contact with the end of the section when the DC motor is energized.

The end guessing determination unit utilizes the phenomenon that the current of the DC motor is superimposed on the phase current detection value of the connection phase to which the DC motor is connected in the multi-phase motor. The end guess determination unit of one aspect estimates the DC motor current value from the phase current detection value of the connection phase, and determines the end guess using the estimated DC motor current value. Alternatively, in a configuration in which the control unit controls the DC motor current value by feedback control, the end guess determination unit of another aspect determines the end guess based on the absolute value of the voltage between the terminals of the DC motor.

In the present invention, the first circuit that energizes the polyphase motor and the second circuit that energizes the DC motor form an integrated power conversion circuit that shares one leg. Therefore, the power conversion circuit that drives a plurality of motors can be miniaturized.

Further, in the present invention, the end contact can be determined by the end contact determination unit. When it is determined that the section moving actuator is in the end contact state, the control unit stops the energization of the DC motor, for example, so that an overcurrent flows in the DC motor or the mechanism is damaged due to the generation of excessive thrust. It is possible to prevent this from happening. Further, since it is not necessary to mount the position sensor, it is possible to avoid an increase in the number of connector pins and the like.

The figure of the column type EPS system to which the motor control device of this embodiment is applied. The figure of the rack type EPS system to which the motor control device of this embodiment is applied. The figure of the SBW system to which the motor control device of this embodiment is applied. (A) Schematic diagram of tilt actuator, (b) Schematic diagram of telescopic actuator. The figure which shows the connection configuration example of a connector. Circuit configuration diagram of an integrated power conversion circuit that drives a single system of three-phase motors. Circuit block diagram of an integrated power conversion circuit that drives two three-phase motors. The schematic diagram which shows the structure of a three-phase double winding rotary machine. A block diagram showing the basic control algorithm of the control unit. (A) A schematic diagram illustrating the end contact of the section moving actuator, and (b) a waveform diagram showing a change in the DC motor current due to the end contact. The block diagram of the end guessing determination part by 1st Embodiment. A circuit diagram illustrating that the DC motor current is superimposed on the phase current of the connection phase as the principle of estimating the DC motor current according to the second to fourth embodiments. The block diagram of the end guessing determination part by 2nd Embodiment. The waveform diagram explaining the estimation of the DC motor current by the 2nd Embodiment. The block diagram of the end guessing determination part by 3rd Embodiment. The waveform diagram explaining the estimation of the DC motor current by the 3rd Embodiment. The block diagram of the end guessing determination part by 4th Embodiment. The waveform diagram explaining the estimation of the DC motor current by the 4th Embodiment. The block diagram of the end guessing determination part by the modification of 4th Embodiment. The flowchart of the end guess determination by 1st to 4th Embodiment. The block diagram which shows the control algorithm of 5th Embodiment. The flowchart of the end guess determination by the 5th Embodiment.

Hereinafter, a plurality of embodiments of the motor control device according to the present invention will be described with reference to the drawings. The motor control device of each embodiment is applied to an electric power steering system (hereinafter, "EPS system") or a steer-by-wire system (hereinafter, "SBW system") of a vehicle, and functions as an EPS-ECU or an SBW-ECU. Hereinafter, EPS-ECU or SBW-ECU are collectively referred to as "ECU". Further, each embodiment described later is collectively referred to as "the present embodiment". Substantially the same configurations in a plurality of embodiments are designated by the same reference numerals and description thereof will be omitted.

[System configuration]
First, with reference to FIGS. 1 to 4, the configuration of the system to which the ECU as the "motor control device" is applied will be described. 1 and 2 show an EPS system 901 in which a steering mechanism and a steering mechanism are mechanically connected. Of these, FIG. 1 shows a column type, and FIG. 2 shows a rack type EPS system 901. When distinguishing, the code of the column type EPS system is described as 901C, and the code of the rack type EPS system is described as 901R. FIG. 3 shows the SBW system 902 in which the steering mechanism and the steering mechanism are mechanically separated. In FIGS. 1 to 3, only one side of the wheel 99 is shown, and the other side of the wheel 99 is not shown.

The EPS system 901 and the SBW system 902 commonly include a three-phase motor 800 as a "multi-phase motor" and DC motors 720 and 730. The three-phase motor 800 in the EPS system 901 is a steering assist motor that assists the steering of the driver, and the three-phase motor 800 in the SBW system 902 is a reaction force motor that applies a reaction force to the steering of the driver. The DC motors 720 and 730 are motors for the tilt actuator 20 and the telescopic actuator 30, respectively. In the description and drawings of the following embodiments, the DC motor will be referred to as "DC motor".

As shown in FIGS. 1 and 2, the EPS system 901 includes a steering wheel 91, a steering shaft 92, an intermediate shaft 95, a steering rack 97, and the like. The steering shaft 92 is included in the steering column 93, and the steering wheel 91 is connected to one end and the intermediate shaft 95 is connected to the other end.

At the end of the intermediate shaft 95 opposite to the steering wheel 91, a steering rack 97 is provided which converts rotation into reciprocating motion by a rack and pinion mechanism and transmits the rotation. When the steering rack 97 reciprocates, the wheels 99 are steered via the tie rod 98 and the knuckle arm 985. Further, universal joints 961 and 962 are provided in the middle of the intermediate shaft 95.

In the column type EPS system 901C shown in FIG. 1, the three-phase motor 800 is arranged in the steering column 93. The output torque of the three-phase motor 800 is transmitted to the steering shaft 92. The torque sensor 94 is provided in the middle of the steering shaft 92, detects torque based on the torsional displacement of the torsion bar, and outputs the torque sensor value T_sns.

In the rack type EPS system 901R shown in FIG. 2, the three-phase motor 800 is arranged in the steering rack 97. The reciprocating motion of the steering rack 97 is assisted by the output torque of the three-phase motor 800. The torque sensor 94 detects the torque transmitted to the steering rack 97 and outputs the torque sensor value T_sns.

The ECU 10 is activated by an ON / OFF signal of the vehicle switch 11. The vehicle switch 11 corresponds to an ignition switch or a push switch of an engine vehicle, a hybrid vehicle, or an electric vehicle. Each signal to the ECU 10 is communicated by using CAN, serial communication, or the like, or is sent as an analog voltage signal.

In the present specification, actuators configured so that a moving body can move in a predetermined section are collectively referred to as "section moving actuators". The steering column 93 is provided with a tilt actuator 20 and a telescopic actuator 30 as section movement actuators. The DC motors 720 and 730 output torque so as to move the moving body in the tilt actuator 20 and the telescopic actuator 30, respectively.

When the driver operates the tilt switch 12 and an instruction of "up / down" is input to the ECU 10, the ECU 10 rotates the DC motor 720 for the tilt actuator 20 in the forward or reverse direction according to the instruction direction. Then, as shown in FIG. 4A, the tilt actuator 20 adjusts the tilt angle and moves the steering wheel 91 up and down. Then, when the vehicle switch 11 is turned on and the vehicle is started, the vehicle moves to a driving position stored in advance, and when the vehicle switch 11 is turned off and the vehicle is stopped, the driver moves to the side where the space becomes wider.

Further, when the driver operates the telescopic switch 13 and an instruction of "extension / contraction" is input to the ECU 10, the ECU 10 rotates the DC motor 730 for the telescopic actuator 30 in the forward or reverse direction according to the instruction direction. .. Then, as shown in FIG. 4B, the telescopic actuator 30 adjusts the telescopic length and moves the steering wheel 91 back and forth. Then, when the vehicle switch 11 is turned on and the vehicle is started, the vehicle moves to a driving position stored in advance, and when the vehicle switch 11 is turned off and the vehicle is stopped, the driver moves to the side where the space becomes wider.

Subsequently, as shown in FIG. 3, in the SBW system 902 in which the steering mechanism and the steering mechanism are mechanically separated, the intermediate shaft 95 does not exist with respect to the EPS system 901. Driver input information such as the steering torque of the driver or the angle of the steering wheel 91 is electrically transmitted to the steering motor 890 via the ECU 10. The rotation of the steering motor 890 is converted into the reciprocating motion of the steering rack 97, and the wheels 99 are steered via the tie rod 98 and the knuckle arm 985. Although not shown in FIG. 3, there is a steering motor ECU that drives the steering motor 890 with respect to the steering wheel input of the driver.

Further, in the SBW system 902, the driver cannot directly sense the reaction force to the steering. Therefore, the ECU 10 controls the drive of the three-phase motor 800, which is a reaction force motor, rotates the steering wheel 91 so as to apply a reaction force to steering, and gives the driver an appropriate steering feeling. Hereinafter, in the description of the ECU 10, there is no difference between the EPS system 901 and the SBW system 902.

The control unit 400 applies a voltage to the three-phase motor 800 and the DC motors 720 and 730 to energize the current. The three-phase inverter circuit 68 as the "first circuit" is a power conversion circuit that energizes the three-phase motor 800. The H-bridge circuit 67 as the "second circuit" is a power conversion circuit that energizes the DC motors 720 and 730.

In the present embodiment, the three-phase inverter circuit 68 and the H-bridge circuit 67 are provided in the same housing 600 together with the control unit 400. This makes it possible to reduce the size of the ECU 10 and reduce the number of wiring parts such as harnesses and connectors. Further, as will be described in detail with reference to FIGS. 6 and 7, the three-phase inverter circuit 68 and the H-bridge circuit 67 form an “integrated power conversion circuit 60” that shares one leg. In FIGS. 1 to 3, the fact that the frames of the three-phase inverter circuit 68 and the H-bridge circuit 67 are partially overlapped means that the two circuits share a leg.

The control unit 400 is composed of a microcomputer, a drive circuit, etc., includes a CPU (not shown), a ROM, a RAM, an I / O, a bus line connecting these configurations, and a substantial memory device such as a ROM (that is,). , Software processing by executing a program stored in advance in a readable non-temporary tangible recording medium by the CPU, and control by hardware processing by a dedicated electronic circuit are executed.

The control unit 400 is provided in common with respect to the three-phase inverter circuit 68 and the H-bridge circuit 67, and controls the operations of the three-phase motor 800 and the DC motors 720 and 730. The control unit 400 operates the three-phase inverter circuit 68 based on the torque sensor value T_sns detected by the torque sensor 94 and the vehicle speed V detected by the vehicle speed sensor 14, and controls the operation of the three-phase motor 800. Further, the control unit 400 operates the H-bridge circuit 67 to control the operation of the DC motors 720 and 730.

Further, the control unit 400 of the present embodiment determines the end contact of the tilt actuator 20 and the telescopic actuator 30 when the DC motors 720 and 730 are energized. The end pad means that the moving body of the section moving actuator comes into contact with the end of the section. As will be described in detail later, when end contact occurs, overcurrent of the DC motors 720 and 730 and damage to the mechanism may occur. In the present embodiment, the control unit 400 determines the end contact of the section moving actuators 20 and 30, so that overcurrent of the DC motors 720 and 730 and damage to the mechanism can be prevented.

Hereinafter, a configuration in which one tilt actuator 20 is connected as the section moving actuator will be described, and the telescopic actuator 30 will be omitted. Next, with reference to FIG. 5, an example of the connector connection configuration is shown. The three-phase motor 800 of the present embodiment is configured as a "mechanical-electrically integrated" brushless three-phase motor in which the ECU 10 is integrally configured on one side in the axial direction. On the other hand, the DC motor 720 for the tilt actuator 20 is connected to the ECU 10 via a connector.

In this connection configuration, the power system connector 191 and the signal system connector 192 and the torque sensor connector 193 are separately provided. A power supply line (PIG) and a ground line from a direct current power supply are connected to the power system connector 191. A control power supply line (IG), a CAN communication line, a drive command signal line, and a motor line (M +, M-) of a DC motor for a section moving actuator are connected to the signal system connector 192. The power line, signal line, and ground line of the torque sensor 94 are collectively connected to the torque sensor connector 193.

Although the motor lines (M +, M-) of the DC motor are power systems, they can be connected by being included in the signal system connector 192 because the motor current is smaller than that of the three-phase motor. If the current of the DC motor is large, it may be a separate connector, or it may be a connector common to the power system connector 191 of the power line (PIG) from the DC power supply and the ground line.

In general, in the wiring of the section moving actuator, it is known that the power line, the signal line, and the ground line of the position sensor are connected in addition to the motor line. The end contact can be determined by detecting that the moving body has reached a predetermined position by the position sensor. However, mounting a position sensor increases the number of connector pins required. In particular, in the EPS system 901 and the SBW system 902, which have many types of input / output signals, securing the number of pins becomes a problem. In the present embodiment, the control unit 400 determines the end contact, so that the position sensor becomes unnecessary and the wiring of the position sensor becomes unnecessary, so that the number of pins used in the connector can be reduced.

[Configuration of integrated power conversion circuit]
Subsequently, a circuit configuration example of the integrated power conversion circuit will be described with reference to FIGS. 6 to 8. First, regarding the three-phase motor 800 to be driven by the three-phase inverter circuit 68, a unit including the three-phase winding set and the three-phase inverter circuit corresponding to the winding set is referred to as a "system". FIG. 6 shows an example of a circuit configuration of one system, and FIG. 7 shows an example of a circuit configuration of two systems. As shown in FIG. 8, in the two-system configuration, the "first circuit" 68 includes two three-phase inverter circuits 681 and 682.

The one-system three-phase winding set is composed of U-phase, V-phase, and W-phase windings 811, 812, and 813 connected at the neutral point N. A voltage is applied to the windings 811, 812, and 813 of each phase from the three-phase inverter circuit 68. In each phase, a counter electromotive voltage proportional to the product of the rotation speed and the sin value of the phase is generated. The counter electromotive force generated in each phase is represented by, for example, equations (1.1) to (1.3) based on the voltage amplitude A, the rotation speed ω, and the phase θ. In the part described later, the rotation speed ω is also referred to as the angular velocity ω, and the phase θ is also referred to as the electric angle θ.

Eu = -Aωsinθ ... (1.1)
Ev = -Aωsin (θ-120) ... (1.2)
Ew = -Aωsin (θ + 120) ... (1.3)

The two-system three-phase motor 800 has two sets of three-phase winding sets 801 and 802. The three-phase winding set 801 of the first system is configured by connecting the U1 phase, V1 phase, and W1 phase windings 811, 812, and 813 at the neutral point N1. A voltage is applied to the windings 811, 812, and 813 of each phase of the three-phase winding set 801 of the first system from the three-phase inverter circuit 681 of the first system. The three-phase winding set 802 of the second system is configured by connecting U2 phase, V2 phase, and W2 phase windings 821, 822, and 823 at the neutral point N2. A voltage is applied to the windings 821, 822, and 823 of each phase of the three-phase winding set 802 of the second system from the three-phase inverter circuit 682 of the second system.

As shown in FIG. 8, the three-phase motor 800 having a two-system configuration is a double-winding rotary machine in which two sets of three-phase winding sets 801 and 802 are coaxially provided. The two sets of three-phase winding sets 801 and 802 have the same electrical characteristics, and are arranged, for example, on a common stator with an electrical angle of 30 [deg] offset from each other. In that case, the counter electromotive voltage generated in each phase of the first system and the second system is based on the voltage amplitude A, the rotation speed ω, and the phase θ, for example, equations (2.1) to (2.3), (2). It is represented by .4a) to (2.6a).

Eu1 = -Aωsinθ ... (2.1)
Ev1 = -Aωsin (θ-120) ... (2.2)
Ew1 = -Aωsin (θ + 120) ... (2.3)
Eu2 = -Aωsin (θ + 30) ... (2.4a)
Ev2 = -Aωsin (θ-90) ... (2.5a)
Ew2 = -Aωsin (θ + 150) ... (2.6a)

When the phase relationship between the two systems is reversed, for example, the phase (θ + 30) of the U2 phase becomes (θ-30). Further, the phase difference equivalent to 30 [deg] is generally expressed as (30 ± 60 × k) [deg] (k is an integer). Alternatively, the second system may be arranged in phase with the first system. In that case, the counter electromotive voltage generated in each phase of the second system is represented by the equations (2.4b) to (2.6b) instead of the equations (2.4a) to (2.6a).

Eu2 = -Aωsin (θ-30) ... (2.4b)
Ev2 = -Aωsin (θ + 90) ... (2.5b)
Ew2 = -Aωsin (θ-150) ... (2.6b)

As the DC motor to be driven by the H-bridge circuit 67, only one DC motor 720 for the tilt actuator 20 will be described as a representative. When driving two or more DC motors, a plurality of similar configurations are provided. When the DC motor 720 is energized, a counter electromotive voltage Ed proportional to the rotation speed ωd is generated in the winding 724. Assuming that the proportionality constant is E, the counter electromotive voltage E is expressed by the equation “Ed = −Eωd”. Further, the direct current applied to the DC motor 720 is referred to as Idc.

Next, examples of circuit configurations of one system and two systems will be described in order. A set of high-potential side and low-potential side switching elements connected in series in the three-phase inverter circuit 68 which is the "first circuit" and the H bridge circuit 67 which is the "second circuit" is referred to as a "leg". do. In the circuit configuration example of one system shown in FIG. 6, one leg of the H-bridge circuit 67 is shared with the U-phase leg of the three-phase inverter circuit 68. For convenience of illustration, the reference numeral "67" seems to indicate the non-shared side leg, but actually, it refers to the portion where the U-phase leg and the non-shared side leg of the three-phase inverter circuit 68 are combined. There is.

As described above, the power conversion circuit configured by sharing the leg of one phase (for example, U phase) of the three-phase inverter circuit 68 and the leg of one side of the H-bridge circuit 67 is described in the present specification as “integrated power conversion”. It is called "circuit". In the circuit configuration example of FIG. 6, one system of the three-phase inverter circuit 68 and the H-bridge circuit 67 form an integrated power conversion circuit 60.

The integrated power conversion circuit 60 is connected to the positive electrode of the power supply Bt via the high potential line Lp and is connected to the negative electrode of the power supply Bt via the low potential line Lg. The power supply Bt is, for example, a battery having a reference voltage of 12 [V]. The DC voltage input from the power supply Bt to the integrated power conversion circuit 60 is referred to as “input voltage Vr”.

A capacitor C is provided between the high potential line Lp and the low potential line Lg on the power supply Bt side of the integrated power conversion circuit 60. In the current path between the power supply Bt and the capacitor C, the power supply relay Pr is connected in series on the power supply Bt side, and the reverse connection protection relay PR is connected in series on the capacitor C side. The power supply relay Pr and the reverse connection protection relay PR are composed of a semiconductor switching element such as a MOSFET, a mechanical relay, or the like, and can cut off the energization from the power supply Bt to the integrated power conversion circuit 60 when the power supply Bt is turned off. The power relay Pr cuts off the current in the flowing direction when the electrodes of the power supply Bt are connected in the normal direction. The reverse connection protection relay PR cuts off the current in the flowing direction when the electrodes of the power supply Bt are connected in the direction opposite to the normal direction.

The three-phase inverter circuit 68 converts the DC power of the power supply Bt into three-phase AC power by the operation of a plurality of bridge-connected inverter switching elements IUH, IUL, IVH, IVL, IWH, and IWL on the high potential side and the low potential side. Then, the three-phase motor 800 is energized. Specifically, the inverter switching elements IUH, IVH, and IWH are upper arm elements provided on the high potential side of the U phase, V phase, and W phase, respectively, and the inverter switching elements IUL, IVL, and IWL are U phase and V, respectively. It is a lower arm element provided on the low potential side of the phase and the W phase. Hereinafter, the upper arm element and the lower arm element of the same phase are collectively referred to as "IUH / L, IVH / L, IWH / L", and "IUH / L" corresponds to the code of the U-phase leg.

Between the lower arm elements IUL, IVL, IWL and the low potential line Lg of each phase of the three-phase inverter circuit 68, current sensors SAU, SAV, SAW for detecting the phase currents Iu, Iv, Iw flowing in each phase are provided. is set up. The current sensors SAU, SAV, and SAW are composed of, for example, a shunt resistor.

The non-shared side leg of the H-bridge circuit 67 is composed of a switching element MUH on the high potential side and a switching element MUL on the low potential side connected in series via the DC motor terminal Mdc. Hereinafter, a set of switching elements constituting the non-shared side leg will be referred to as a "DC motor switching element". Similar to the inverter switching element, the high potential side and low potential side switching elements are collectively referred to as "MUH / L" as the reference numeral of the DC motor switching element.

Each phase inverter switching element IUH / L, IVH / L, IWH / L of the three-phase inverter circuit 68, and the switching element MUH / L for a DC motor are, for example, MOSFETs. In addition, the switching element may be a field effect transistor other than the MOSFET, an IGBT, or the like. Here, the current energized in the DC motor 720 is smaller than the phase current flowing in the three-phase motor 800. Therefore, as the DC motor switching element MUH / L, a switch having a current capacity smaller than that of the inverter switching elements IUH / L, IVH / L, and IWH / L may be used.

The first terminal T1, which is one terminal of the DC motor 720, is connected to the branch point Ju of the U-phase current path of the three-phase winding set. The second terminal T2, which is the other terminal of the DC motor 720, is connected to the DC motor terminal Mdc between a set of high-potential side and low-potential side switching elements in the H-bridge circuit 67. The DC motor switching element MUH / L is connected to the U-phase winding 811 via the DC motor 720. Hereinafter, the phase to which the DC motor 720 is connected in the three-phase motor 800 is referred to as a “connection phase”. The "U" in the code "MUH / L" of the switching element for a DC motor means the U phase which is the connection phase. When two or more DC motors are connected to a common three-phase motor 800, the connection phase of each DC motor may be the same phase or a different phase.

The phase currents energized in the three-phase winding set are referred to as Iu #, Iv #, and Iw # with respect to the phase currents Iu, Iv, and Iw flowing in the three-phase inverter circuit 68. In the example of FIG. 6, a part of the phase current Iu is separated as the DC motor current Idc at the branch point Ju of the U-phase current path which is the connection phase. What is the relationship between the inverter phase currents Iu, Iv, Iw flowing on the three-phase inverter circuit 68 side of the branch point Ju and the motor phase currents Iu #, Iv #, Iw # energized on the three-phase motor 800 side of the branch point Ju? , Expressed by equations (3.1) to (3.4). The relationship of equation (3.4) is used in the second and third embodiments.

Iu # = -Iv-Iw ... (3.1)
Iv # = Iv ... (3.2)
Iw # = Iw ... (3.3)
Idc = Iu-Iu # = Iu + Iv + Iw ... (3.4)

In the DC motor 720, the direction of the current Idc from the first terminal T1 to the second terminal T2 is the positive direction, and the direction of the current Idc from the second terminal T2 to the first terminal T1 is the negative direction. An inter-terminal voltage Vx is applied between the first terminal T1 and the second terminal T2. The sign of the voltage between terminals Vx is positive when the voltage of the first terminal T1 is higher than the voltage of the second terminal T2. The DC motor 720 rotates forward when energized in the positive direction and reverses when energized in the negative direction.

The control unit 400 controls the operation of the three-phase motor 800 based on the phase current detection values Iu, Iv, Iw detected by the current sensors SAU, SAV, and SAW, and the electric angle θ or the angular velocity ω of the three-phase motor 800. .. Further, the control unit 400 outputs a "gate signal" to the three-phase inverter circuit 68 while operating the center voltage of the three-phase voltage command value of the three-phase motor 800. At the same time, the control unit 400 outputs a "DC motor drive command" to turn on one of the DC motor switching elements MUH / L and turn off the other according to the rotation direction of the DC motor 720.

That is, when the DC motor 720 is energized in the positive direction, the control unit 400 turns on the low potential side switching element, turns off the high potential side switching element, and sets the voltage of the branch point Ju of the connection phase to the DC motor terminal Mdc. The voltage between terminals Vx is adjusted to a positive value by setting it higher than the voltage of. Further, when the DC motor 720 is energized in the negative direction, the control unit 400 turns on the high potential side switching element, turns off the low potential side switching element, and sets the voltage of the branch point Ju of the connection phase to the DC motor terminal Mdc. The voltage between terminals Vx is adjusted to a negative value by setting it lower than the voltage of.

As described above, the three-phase inverter circuit 68 that energizes the three-phase motor 800 and the H-bridge circuit 67 that energizes the DC motor 720 are one of the one-phase legs of the three-phase inverter circuit 68 and one side of the H-bridge circuit 67. It forms an integrated power conversion circuit 60 that shares with the legs. Therefore, the power conversion circuit that drives a plurality of motors can be miniaturized.

Further, the control unit 400 of the present embodiment has an end guess determination unit 50. In the first embodiment among the plurality of embodiments described later, the end guess determination unit 50 detects the DC motor current value Idc_sns from the current sensor 75 provided in the current path of the DC motor 720, as shown by the broken line. get. In the second to fourth embodiments, the end guessing determination unit 50 is the DC motor current value Idc based on the phase current detection values Iu, Iv, Iw input to the control unit 400 and the information of the angular velocity ω of the three-phase motor 800. To estimate. Hereinafter, depending on the context, the presence or absence of a "value" such as "DC motor current" and "DC motor current value" may coexist. Basically, "current value" is a word that emphasizes that it is a "value", but it does not make a strict distinction.

In the two-system circuit configuration example shown in FIG. 7, the “first circuit” 68 (see FIG. 8 for reference numerals) that energizes the three-phase motor 800 is composed of the two-system three-phase inverter circuits 681 and 682. The three-phase inverter circuit 681 of the first system is connected to the U1 phase, V1 phase, and W1 phase windings 811, 812, and 813 of the three-phase winding set 801. The three-phase inverter circuit 682 of the second system is connected to the U2-phase, V2-phase, and W2-phase windings 821, 822, and 823 of the three-phase winding set 802. The code of the component of the second system and the symbol of the current are represented by replacing "1" of the code of the component of the first system and the symbol of the current with "2". Further, regarding the components of the second system, the description of the components of the first system is incorporated.

The three-phase inverter circuit 681 of the first system is provided with inverter switching elements IU1H / L, IV1H / L, IW1H / L, and current sensors SAU1, SAV1, and SAW1 for detecting the phase currents Iu1, Iv1, and Iw1. ing. A capacitor C1 is provided on the power supply Bt side of the three-phase inverter circuit 681. Further, a power supply relay P1r and a reverse connection protection relay P1R are provided between the power supply Bt and the three-phase inverter circuit 681. The DC voltage input from the power supply Bt to the three-phase inverter circuit 681 is referred to as "input voltage Vr1". Phase currents Iu1 #, Iv1 #, and Iw1 # are energized in the three-phase winding set 801.

In the configuration example of FIG. 7, the circuit of the first system is configured in the same manner as the circuit of one system shown in FIG. That is, the first terminal T1 of the DC motor 720 is connected to the branch point Ju of the U1 phase current path which is the connection phase of the three-phase winding set 801 of the first system, and the three-phase inverter circuit 681 of the first system The U1 phase leg is shared with one leg of the H-bridge circuit 67. On the other hand, the circuit of the second system is not directly connected to the DC motor 720 and is used exclusively for driving the three-phase motor 800. Further, the point where the control unit 400 has the end guess determination unit 50 and the signal input to the end guess determination unit 50 are the same as those in FIG. 6, so they are omitted. In the following description, one system configuration is shown as a basis. When the three-phase motor 800 has a two-system configuration, the control of the second system may be added and interpreted as appropriate to the control of the first system.

[Basic control algorithm]
Next, with reference to FIG. 9, an example of a basic control algorithm in which the control unit 400 drives the three-phase motor 800 and the DC motor 720 having a single system configuration will be described. The control unit 400 includes a q-axis current deviation calculator 43, a q-axis current controller 44, a d-axis current deviation calculator 45, a d-axis current controller 46, a dq / three-phase conversion unit 47, and a neutral point voltage operation unit 48. And a PWM modulator 49.

The q-axis current deviation calculator 43 calculates the q-axis current deviation ΔIq between the q-axis current command Iq ^* and the fed-back q-axis current Iq. The q-axis current controller 44 calculates the q-axis voltage command Vq ^* so that the q-axis current deviation ΔIq approaches 0, in other words, the q-axis current Iq follows the q-axis current command Iq ^* . The q-axis current command Iq ^* is calculated by torque control, position control, speed control, current control, voltage control, and the like. Further, it may be limited to the current limit value or less as needed.

The d-axis current deviation calculator 45 calculates the d-axis current deviation ΔId between the d-axis current command Id ^* and the fed-back d-axis current Id. The d-axis current controller 46 calculates the d-axis voltage command Vd ^* so that the d-axis current deviation ΔId approaches 0, in other words, the d-axis current Id follows the d-axis current command Id ^* .

The dq / three-phase conversion unit 47 converts the dq-axis voltage commands Vq ^* and Vd ^* into the three-phase voltage commands Vu ^* , Vv ^* and Vw ^* . The signal of the electric angle θ input to the dq / three-phase conversion unit 47 for the coordinate conversion calculation is omitted. The center voltage of the three-phase voltage commands Vu ^* , Vv ^* , and Vw ^* output by the dq / three-phase conversion unit 47 is 0 [V].

The center voltage operation unit 48 operates the center voltage of the three-phase voltage command values Vu ^* , Vv ^* , and Vw ^* using the offset voltage Vm ^* . For example, when the input voltage Vr is 12 [V], the center voltage in the non-driving state of the DC motor 720 is offset to 6 [V]. When energized in the positive direction of the DC motor 720, the center voltage is offset to a value close to 12 [V] so that the absolute value | Vx | of the positive terminal voltage increases as the required torque increases. When the DC motor 720 is energized in the negative direction, the center voltage is offset to a value close to 0 [V] so that the absolute value | Vx | of the negative terminal voltage increases as the required torque increases.

The PWM modulator 49 PWM-modulates the three-phase voltage command after the center voltage operation to generate a gate signal. The gate signal output by the PWM modulator 49 is input to each gate of the inverter switching elements IUH / L, IVH / L, and IWH / L of the three-phase inverter circuit 68 shown in FIG.

[Structure of end guess judgment unit]
Next, with reference to FIGS. 10 (a) and 10 (b), the end contact in the section moving actuator will be described. FIG. 10A schematically shows a configuration example of the section movement actuator by using the reference numeral “20” of the tilt actuator as a representative of the section movement actuator.

For example, in the section moving actuator 20, the ball screw 23 is rotatably supported between the end members 27 and 28 provided at both ends of the section. The ball screw 23 is connected to the output shaft of the DC motor 720 and rotates in the forward and reverse directions according to the rotation of the DC motor 720. Along with this, the moving body 24 screwed into the ball screw 23 is guided by a mechanism (not shown) and reciprocates between the end members 27 and 28. Then, when the moving body 24 comes into contact with one end member 27 or the other end member 28, the end contact state is established.

Here, the applied voltage Vx of the DC motor 720 is represented by the equation (4) using the inductance L and resistance R of the winding 724, the differential operator s, and the counter electromotive voltage Eωd.
Vx = (Ls + R) x Idc + Eωd ... (4)

In the end contact state, the rotation stops and the angular velocity ωd = 0, so that the counter electromotive voltage term becomes 0. Therefore, as shown in FIG. 10B, the absolute value | Idc | of the DC motor current value suddenly increases when the end is applied from the normal driving time. Utilizing this phenomenon, the end guess determination unit 50 determines the end guess based on the sudden increase in the absolute value | Idc | of the detected or estimated DC motor current value.

Subsequently, with reference to FIGS. 11 to 22, the end guess determination according to each embodiment will be described in order. One method of the end guess determination will be described with reference to the flowchart of FIG. 20 after explaining the configuration of the first to fourth embodiments. Further, another method of the end guess determination will be described with reference to the flowchart of FIG. 22 after explaining the configuration of the fifth embodiment. Hereinafter, the reference numeral of the end guess determination unit of each embodiment is the number of the embodiment in the third digit following “50”.

(First Embodiment)
FIG. 11 shows the configuration of the end guess determination unit 501 of the first embodiment. As shown by the broken line in FIG. 6, in the first embodiment, the current sensor 75 is provided in the current path of the DC motor 720. The end guess determination unit 501 determines the end guess using the detected value Idc_sns of the DC motor current value acquired from the current sensor 75. In the first embodiment, since the estimation calculation of the DC motor current Idc is not performed, the calculation load can be reduced.

(Common matters of the second to fourth embodiments)
In the second to fourth embodiments, it is assumed that the DC motor current sensor 75 shown by the broken line in FIG. 6 is not provided. The end guessing determination units 502, 503, and 504 of the second to fourth embodiments estimate the DC motor current value Idc based on the phase current detection value Iu of the connection phase of the three-phase motor 800, and the estimated DC motor current value. Idc_est is used to determine the end guess. In the second to fourth embodiments, the DC motor current sensor 75 is not required, which is advantageous in terms of mounting space and component cost reduction.

The estimation principle of the DC motor current value Idc will be described with reference to FIG. Due to the Duty operation of the U-phase leg IUH / IUL of the three-phase inverter circuit 68, the U-phase current Iu # of the three-phase motor 800 flows from the high potential line Lp to the low potential line Lg in the path of the thick solid line arrow. Further, when the DC motor switching element MUH on the high potential side is turned on and the DC motor switching element MUH on the high potential side is turned off, the DC motor current Idc flows in the path indicated by the thick broken line arrow.

Therefore, the current Iu in which the DC motor current Idc is superimposed on the U-phase current Iu # flows through the current sensor SAU. That is, the value obtained by superimposing the DC motor current Idc on the U-phase current Iu # is detected as the U-phase current detection value Iu by the current sensor SAU. Therefore, the end guessing determination units 502, 503, and 504 can estimate the DC motor current Idc by extracting the DC motor current Idc from the U-phase current detection value Iu.

The following FIGS. 14, 16 and 18 show waveforms of the U-phase current detection value Iu on which the positive DC motor current Idc is superimposed at the start of energization of the DC motor 720. When energization is started at time ts, the DC motor current value Idc increases due to the inrush current and reaches a peak at time tp. After the time tp, the DC motor current value Idc gradually decreases. If the end is applied while the DC motor 720 is energized, the DC motor current value Idc increases sharply as shown in FIG. 10 (b).

(Second Embodiment)
The end guess determination unit 502 of the second embodiment will be described with reference to FIGS. 13 and 14. The sum of the three-phase currents Iu #, Iv #, and Iw # flowing through the phase windings 811, 812, and 813 of the three-phase motor 800 is theoretically zero. Therefore, as shown in the above equation (3.4), the difference between the sum of the three-phase phase current detection values Iu, Iv, and Iw and zero corresponds to the DC motor current value Idc. Therefore, the end guessing determination unit 502 extracts the superimposed DC motor current Idc by adding the U-phase current detection value Iu, the V-phase current detection value Iv, and the W-phase current detection value Iw. As described above, the end guessing determination unit 502 estimates the sum of the three-phase current detection values Iu, Iv, and Iw of the three-phase motor 800 as the DC motor current value Idc_est.

(Third Embodiment)
The end guess determination unit 503 of the third embodiment will be described with reference to FIGS. 15 and 16. The U-phase current detection value Iu is a value obtained by adding the DC motor current value Idc to the U-phase current command value Iu ^* related to the energization of the U-phase winding 811 of the three-phase motor 800. Therefore, the end guessing determination unit 503 extracts the superimposed DC motor current Idc by subtracting the U-phase current command value Iu ^* from the U-phase current detection value Iu. This idea corresponds to the equation in which the motor phase current Iu # is replaced with the U phase current command value Iu ^* in the equation (3.4). As described above, the end guessing determination unit 503 estimates the difference between the phase current detection value and the phase current command value of the connection phase of the three-phase motor 800 as the DC motor current value Idc_est.

(Fourth Embodiment)
The end guess determination unit 504 of the fourth embodiment will be described with reference to FIGS. 17 and 18. The end guessing determination unit 504 has a low-pass filter 541 that filters the phase current detection value Iu and separates it into an AC current component and a DC current component. The low-pass filter 541 extracts the DC current component superimposed on the AC current component as the DC motor current Idc. In this way, the end guessing determination unit 504 filters the phase current detection value of the connection phase of the three-phase motor 800 to separate the AC current component and the DC current component, and sets the value of the DC current component to the DC motor current. Estimated as the value Idc_est.

FIG. 19 shows an end guess determination unit 504T of a modified example of the fourth embodiment. The end guess determination unit 504T has a cutoff frequency setting unit 542 in addition to the low-pass filter 541. The cutoff frequency setting unit 542 changes the cutoff frequency fco according to the angular velocity ω of the three-phase motor 800. Specifically, the cutoff frequency fco is reduced in the low speed range, and the cutoff frequency fco is increased in the high speed range. Since the frequency of the alternating current increases as the speed increases, increasing the cutoff frequency fco improves the extraction speed and accuracy of the DC motor current value Idc.

Since the relationship between the cutoff frequency fco of the filter processing by the low-pass filter 541 and the filter time constant τ is expressed by fco = (1 / 2πτ), changing the cutoff frequency fco and the filter time constant τ are changed. That is virtually the same. In this way, the end guess determination unit 504T changes the filter time constant τ of the filtering process according to the angular velocity ω of the three-phase motor 800.

(End guess determination of the first to fourth embodiments)
Next, with reference to the flowchart of FIG. 20, the end guess determination based on the DC motor current value Idc detected or estimated according to the first to fourth embodiments will be described. The symbol "S" in the flowchart indicates a step. In the description of FIG. 20, “50”, which is a general code of the end guess determination unit, is used. In S13, the end guess determination unit 50 detects or estimates the DC motor current value Idc.

In S14, it is determined whether the absolute value | Idc | of the DC motor current value exceeds the current threshold value Idc_th. In this example, the number of times that YES is determined in S14 is counted, and when the predetermined number of times is reached, the affirmative judgment of S14 is confirmed. If NO in S14, "count value = 0" is output in S15, and the routine ends. If YES in S14, the count value is incremented in S16.

In S17, it is determined whether the count value has reached the threshold value Count_th, and if NO, the process from S14 is repeated. If YES in S17, the end contact determination unit 50 determines in S18 that the end contact is in the end contact state, and stops energizing the DC motor 720.

As described above, in the first to fourth embodiments, the end guess determination unit 50 can determine the end guess based on the fact that the absolute value | Idc | of the DC motor current value exceeds the current threshold value Idc_th. Further, when it is determined that the section moving actuator is in the end contact state, the control unit 400 stops the energization of the DC motor 720, so that an overcurrent flows in the DC motor 720 and an excessive thrust is generated. This makes it possible to prevent the mechanism from being damaged.

(Fifth Embodiment)
Next, with reference to FIGS. 21 and 22, the end guess determination according to the fifth embodiment will be described. In FIG. 21, in addition to the control algorithm shown in FIG. 9, the operation of the offset voltage Vm ^* that operates the center voltage of the three-phase voltage command values Vu ^* , Vv ^* , and Vw ^* in the center voltage operation unit 48 is added. Is shown.

In addition to the configuration shown in FIG. 9, the control unit 400 includes a DC motor current deviation calculator 55 and a DC motor current controller 56. The DC motor current deviation calculator 55 calculates the DC motor current deviation ΔIdc between the DC motor current command Idc ^* and the fed-back DC motor current value Idc. The DC motor current value Idc to be fed back may be a detected value Idc_sns as in the first embodiment, or may be an estimated estimated value Idc_est as in the second to fourth embodiments.

The DC motor current controller 56 calculates the offset voltage Vm ^* so that the DC motor current deviation ΔIdc approaches 0, in other words, the DC motor current Idc follows the DC motor current command Idc ^* , and the phase voltage command value. Manipulate the center voltage of Vu ^* , Vv ^* , Vw ^* . As described above, the voltage Vx between terminals of the DC motor 720 changes by manipulating the center voltage according to the ON / OFF of the switching element MUH / L for the DC motor. Then, the absolute value | Idc | of the DC motor current value changes with the absolute value | Vx | of the voltage between the terminals. The changed DC motor current value Idc is fed back to the DC motor current deviation calculator 55.

In this way, the control unit 400 controls the DC motor current value Idc by feedback control using the center voltage of the phase voltage command values Vu ^* , Vv ^* , and Vw ^* of the three-phase motor 800 as the operation amount. This control is different from the general open control in a DC motor, and is based on the idea of accurately controlling the torque of the DC motor as in the control of the three-phase motor.

In this control configuration, when the absolute value | Idc | of the DC motor current value suddenly increases due to the end padding, the DC motor current controller 56 determines the phase voltage command value in the direction of decreasing the absolute value | Vx | of the voltage between terminals. Manipulate the center voltage of Vu ^* , Vv ^* , Vw ^* . Therefore, the end guess determination unit 505 of the fifth embodiment recognizes that the absolute value | Vx | of the voltage between terminals has become smaller based on, for example, a change in the offset voltage Vm ^* , and determines the end guess based on this. ..

FIG. 22 describes the end guess determination according to the fifth embodiment. The control unit 400 feeds back the DC motor current value Idc to the command value Idc ^* in S51, and operates the center voltage of the phase voltage command values Vu ^* , Vv ^* , and Vw ^* of the three-phase motor 800 in S52. In S53, the end guess determination unit 505 acquires information on the terminal voltage Vx based on, for example, the offset voltage Vm ^* . This acquisition includes calculations and detections.

In S54, it is determined whether the absolute value | Vx | of the voltage between the terminals is below the voltage threshold value Idc_th. Since S15 to S18 after S54 are the same as the flowchart of FIG. 20, the same step numbers are assigned and the description thereof will be omitted.

In the fifth embodiment, the end guess determination unit 505 can determine the end guess based on the fact that the absolute value | Vx | of the voltage between terminals is below the voltage threshold value Idc_th. In addition, when end contact occurs, the absolute value | Vx | of the voltage between terminals is suppressed by feedback control, so the mechanism itself causes an overcurrent to flow in the DC motor 720 and the generation of excessive thrust. It is possible to prevent damage in advance.

(Other embodiments)
(A) In the present invention, the DC motor can be used not only for tilt actuators and telescopic actuators, but also for various section movement actuators such as steering locks, seats, and slide doors that reciprocate a moving body in a predetermined section. Further, the polyphase motor is not limited to the steering assist motor of EPS. For example, as a vehicle motor in which a multi-phase motor and a DC motor are arranged close to each other, it can be applied to a combination of a brake hydraulic pump motor and an electric parking brake motor, an electric water pump motor and an electric fan motor, and the like. Is. Furthermore, the present invention may be applied to motors other than those for automobiles.

(B) The mechanism for moving the moving body in the section moving actuator is not limited to the one using the ball screw illustrated in FIG. 10 (a), and may be configured by appropriately combining a reduction gear mechanism, a rack and pinion mechanism, and the like. .. The DC motor itself may be configured to move with the moving body.

(C) The "multi-phase motor" is not limited to a three-phase motor, but may be a four-phase or higher-phase motor. In that case, the "sum of the current detection values of the three phases of the three-phase motor" in the second embodiment is generalized to the "sum of the current detection values of all the phases of the multi-phase motor".

(D) A three-phase motor relay or a DC motor relay may be added to the one-system or two-system circuit configuration shown in FIGS. 6 and 7, or an LC filter circuit may be added to the input unit. The first circuit and the second circuit may be connected to individual power supplies instead of being connected to a common power supply Bt. Further, two or more DC motors may be connected to the same phase or different phases of the same system, or to different systems.

The present invention is not limited to such embodiments, and can be implemented in various embodiments without departing from the spirit of the present invention.

The controls and methods thereof described in the present disclosure are realized by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. May be done. Alternatively, the controls and methods thereof described in the present disclosure may be implemented by a dedicated computer provided by configuring the processor with one or more dedicated hardware logic circuits. Alternatively, the controls and methods described herein are by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. It may be realized by one or more dedicated computers configured. Further, the computer program may be stored in a computer-readable non-transitional tangible recording medium as an instruction executed by the computer.

10 ... ECU (motor control unit),
20 ... Tilt actuator (section moving actuator), 24 ... Moving body,
30 ... Telescopic actuator (section movement actuator),
400 ... Control unit,
50 (501-505) ... End guess judgment unit,
60 ... Integrated power conversion circuit,
67 ... H-bridge circuit (second circuit),
68 (681, 682) ... Three-phase inverter circuit (first circuit),
720, 730 ... DC motor (DC motor),
800 ... Three-phase motor (multi-phase motor).

Claims (12)

The first circuit (68, 681, 682), which is a power conversion circuit that energizes the multi-phase motor (800), and
In a section moving actuator (20, 30) configured so that a moving body (24) can move in a predetermined section, power conversion for energizing a DC motor (720, 730) that outputs torque so as to move the moving body. The second circuit (67), which is a circuit, and
A control unit (400) that operates the first circuit and the second circuit to control the operation of the polyphase motor and the DC motor.
Equipped with
The first circuit and the second circuit are provided in the same housing (600), and a set of high potential side and low circuit connected in series in the first circuit and the second circuit. When the potential side switching element is a leg, one terminal of the DC motor is connected to the one-phase phase current path of the polyphase motor, and the other terminal of the DC motor is a set of heights in the second circuit. By being connected between the potential side and low potential side switching elements, the first circuit and the second circuit form an integrated power conversion circuit (60) that shares one leg.
The control unit is a motor control device having an end-hit determination unit (50) for determining an end-hit that the moving body of the section-moving actuator has come into contact with the end of the section when the DC motor is energized. The motor control device according to claim 1, wherein the control unit applies a voltage to the DC motor and the polyphase motor to energize the current. The end guess determination unit (501) is
The motor control device according to claim 2, wherein the end contact is determined using the detected value of the DC motor current value flowing through the DC motor. The end guess determination unit (502, 503, 504, 504T) is
The DC motor current value flowing through the DC motor is estimated based on the phase current detection value of the connection phase to which the DC motor is connected in the multi-phase motor, and the end guess is determined using the estimated DC motor current value. The motor control device according to claim 2. The end guess determination unit (502) is
The motor control device according to claim 4, wherein the sum of the current detection values of all the phases of the multi-phase motor is estimated as the DC motor current value. The end guess determination unit (503) is
The motor control device according to claim 4, wherein the difference between the phase current detection value and the phase current command value of the connection phase of the multi-phase motor is estimated as the DC motor current value. The end guess determination unit (504, 504T) is
The fourth aspect of claim 4, wherein the phase current detection value of the connection phase of the multi-phase motor is filtered to separate an AC current component and a DC current component, and the value of the DC current component is estimated as the DC motor current value. Motor control device. The end guess determination unit (504T) is
The motor control device according to claim 7, wherein the filter time constant of the filtering process is changed according to the angular velocity of the multi-phase motor. The end guess determination unit
The motor control device according to any one of claims 3 to 8, wherein when the absolute value of the DC motor current value exceeds the current threshold value, the end contact state is determined. The motor control device according to any one of claims 3 to 8, wherein the control unit controls the DC motor current value by feedback control using the center voltage of the phase voltage command value of the polyphase motor as an operation amount. The end guess determination unit (505) is
The motor control device according to claim 10, wherein when the absolute value of the voltage between terminals of the DC motor falls below the voltage threshold value due to the feedback control, it is determined that the end contact state is reached. The multi-phase motor is a steering assist motor that assists the driver's steering in the electric power steering system of the vehicle, or a reaction force motor that applies a reaction force to the driver's steering in the steer-by-wire system.
The motor control device according to any one of claims 1 to 11, wherein the section moving actuator is a tilt actuator (20) or a telescopic actuator (30) that changes the steering position.

Images