CN111164865A

CN111164865A - Motor module and electric power steering apparatus

Info

Publication number: CN111164865A
Application number: CN201880062720.7A
Authority: CN
Inventors: 远藤修司; 大桥弘光
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2017-10-06
Filing date: 2018-10-05
Publication date: 2020-05-15
Also published as: WO2019070068A1

Abstract

Provided is a motor module which can realize high output of a motor. The disclosed motor module (1000) is provided with: a motor (200) having n-phase windings, n being an integer of 3 or more; a 1 st substrate (CB1) connected to a 1 st power source (410); a 1 st inverter (120) mounted on the 1 st substrate and connected to the n-phase winding; a 1 st motor control device (310) which is mounted on the 1 st substrate and controls the switching operation of the 1 st inverter switching elements; a 2 nd substrate (CB2) connected to a 2 nd power supply (420), the 2 nd power supply (420) generating the same power supply voltage as the 1 st power supply; a 2 nd inverter (130) mounted on the 2 nd substrate and connected to the n-phase winding; and a 2 nd motor control device (320) mounted on the 2 nd substrate and controlling switching operations of the plurality of switching elements of the 2 nd inverter.

Description

Motor module and electric power steering apparatus

Technical Field

The present disclosure relates to a motor module and an electric power steering apparatus.

Background

In recent years, an electromechanical integrated motor has been developed in which an electric motor (hereinafter, simply referred to as "motor"), a power conversion device that converts electric power from a power supply into electric power to be supplied to the motor, and an Electronic Control Unit (ECU) are integrated. In particular, in the field of vehicle mounting, it is required to ensure high quality from the viewpoint of safety. Therefore, a redundant design is adopted which can continue the safety operation even when a part of the components is failed. As an example of the redundant design, it is studied to provide two power conversion devices for one motor.

Patent document 1 discloses a motor module having: a motor having a pair of winding sets; a pair of inverter circuits that supply power to the pair of winding groups; a pair of predrivers connected to a pair of inverter circuits; and a microcontroller controlling the pair of pre-drivers. In the present specification, a configuration in which a pair of inverter circuits and a pair of winding groups are connected as in patent document 1 is referred to as a "double inverter configuration". The motor module of patent document 1 includes a power supply board and a control board. Passive elements such as a smoothing capacitor and a choke coil are mounted on the power supply board, and control circuits such as a microcontroller and a pre-driver are mounted on the control board.

Patent document 2 discloses a motor module having a dual inverter structure. Similarly to patent document 1, the motor module of patent document 2 also has two substrates, one of which is mounted with passive elements such as a smoothing capacitor and a choke coil, and the other of which is mounted with a control circuit such as a microcontroller and a pre-driver.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5177711

Patent document 2: japanese laid-open patent publication No. 2017-191093

Disclosure of Invention

Problems to be solved by the invention

In the above-described conventional techniques, further improvement in the output of the motor is required.

Embodiments of the present disclosure provide a motor module capable of achieving power redundancy and achieving high output of a motor, and an electric power steering apparatus having the motor module.

Means for solving the problems

An exemplary motor module of the present disclosure has: a motor having n-phase windings, n being an integer of 3 or more; a 1 st substrate connected to a 1 st power supply; a 1 st inverter mounted on the 1 st substrate and connected to the n-phase winding; a 1 st motor control device mounted on the 1 st substrate and controlling switching operations of a plurality of switching elements of the 1 st inverter; a 2 nd substrate connected to a 2 nd power supply, the 2 nd power supply generating the same power supply voltage as the 1 st power supply; a 2 nd inverter mounted on the 2 nd substrate and connected to the n-phase winding; and a 2 nd motor control device mounted on the 2 nd substrate and controlling switching operations of the plurality of switching elements of the 2 nd inverter.

Effects of the invention

According to an exemplary embodiment of the present disclosure, a motor module capable of achieving power redundancy and high output of a motor, and an electric power steering apparatus having the motor module are provided.

Drawings

Fig. 1 is a block diagram illustrating a representative block structure of a motor module 1000 of the present disclosure.

Fig. 2 is a circuit diagram showing a representative FHB type circuit configuration of the power conversion apparatus 100 of the present disclosure.

Fig. 3 is a block diagram showing a typical block structure of the 1 st motor control device 310.

Fig. 4 is a schematic diagram illustrating the configuration of the motor module 1000 of the present disclosure.

Fig. 5 is a block diagram showing a block structure of the motor control device of exemplary embodiment 1.

Fig. 6 is a block diagram showing another block configuration of the motor control device of exemplary embodiment 1.

Fig. 7 is a circuit diagram showing an example of the circuit configuration of the booster circuit.

Fig. 8 is a block diagram showing still another block configuration of the motor control device according to exemplary embodiment 1.

Fig. 9 is a circuit diagram showing an example of the circuit configuration of the step-down circuit.

Fig. 10 is a schematic diagram showing a mounting situation of electronic components between the substrate CB1 and the substrate CB2 in a cross section of the motor module 1000 in a case of being cut along the central axis 211.

Fig. 11 is a schematic diagram showing a mounting situation of electronic components between the substrate CB1 and the substrate CB2 in a cross section of the motor module 1000 in a case of being cut along the central axis 211.

Fig. 12 is a schematic diagram showing a mounting situation of electronic components between the substrate CB1 and the substrate CB2 in a cross section of the motor module 1000 in a case of being cut along the central axis 211.

Fig. 13 is a circuit diagram showing a circuit configuration of a modification example of the power conversion device 100 of embodiment 1.

Fig. 14 is a block diagram showing the block structure of the motor control device of the exemplary embodiment 2.

Fig. 15 is a block diagram showing another block configuration of the motor control device of exemplary embodiment 2.

Fig. 16 is a schematic diagram showing a mounting situation of electronic components between the substrate CB1 and the substrate CB2 in a cross section of the motor module 1000 in a case of being cut along the central axis 211.

Fig. 17 is a schematic diagram showing a mounting situation of electronic components between the substrate CB1 and the substrate CB2 in a cross section of the motor module 1000 in a case of being cut along the central axis 211.

Fig. 18A is a schematic diagram showing a case where electronic components are mounted on both surfaces of a substrate CB 1.

Fig. 18B is a schematic diagram showing a case where electronic components are mounted on both surfaces of the board CB 1.

Fig. 19 is a schematic diagram illustrating a situation of arrangement in the z-axis direction of the substrate CB1 and the substrate CB2 in the motor module 1000 of the illustrated embodiment 2.

Fig. 20 is a schematic diagram showing a typical configuration of an exemplary electric power steering apparatus 3000 according to embodiment 3.

Detailed Description

Hereinafter, embodiments of the motor module and the electric power steering apparatus 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 known matters and repetitive descriptions of substantially the same structure may be omitted. In addition, one embodiment may be combined with another embodiment as long as a contradiction does not occur.

In the present specification, an embodiment of the present disclosure will be described by taking, as an example, a full H-bridge (FHB) type power converter that converts power from a power supply into power to be supplied to a three-phase motor having three-phase (a-phase, B-phase, and C-phase) windings. However, a power conversion device that converts power from a power supply into power to be supplied to an n-phase motor having windings of four or five equal n phases (n is an integer of 4 or more) also falls within the scope of the present disclosure. Further, a power conversion device having a double inverter structure as in

patent document

1 or 2 also belongs to the scope of the present disclosure.

First, a representative block structure of the motor module 1000 of the present disclosure will be described with reference to fig. 1.

Fig. 1 illustrates a representative block structure of a motor module 1000 of the present disclosure. The motor module 1000 includes a power conversion device 100, a motor 200, a 1 st motor control device 310, and a 2 nd motor control device 320, wherein the power conversion device 100 includes a 1 st inverter 120 and a 2 nd inverter 130. The motor module 1000 is connected to the 1 st power source 410 and the 2 nd power source 420 outside via a wire harness. In the present specification, the 1 st motor control device 310 and the 2 nd motor control device 320 may be collectively referred to as a "motor control device".

The motor module 1000 may be modularized to be manufactured and sold as an electromechanically integrated motor having, for example, a motor, a sensor, a driver, and a controller. The motor module 1000 is preferably used for an Electric Power Steering (EPS) device, for example. The power conversion apparatus 100 and the motor control apparatus other than the motor 200 may be modularized and manufactured and sold.

A typical FHB type circuit configuration of the power conversion apparatus 100 of the present disclosure will be described with reference to fig. 2. However, as described above, the power conversion apparatus 100 may have a double inverter structure.

Fig. 2 shows a representative FHB type circuit configuration of the power conversion apparatus 100 of the present disclosure. The power conversion apparatus 100 has a 1 st inverter 120 and a 2 nd inverter 130. The power conversion apparatus 100 converts the power from the 1 st power source 410 and the 2 nd power source 420 into the power supplied to the motor 200. For example, the 1 st and 2

nd inverters

120 and 130 can convert the dc power into three-phase ac power that is pseudo sine waves of a phase, B phase, and C phase.

The motor 200 is, for example, a three-phase ac motor. The motor 200 has a winding M1 of a phase, a winding M2 of B phase, and a winding M3 of C phase, and is connected to the 1 st inverter 120 and the 2 nd inverter 130. Specifically, the 1 st inverter 120 is connected to one end of the winding of each phase of the motor 200, and the 2 nd inverter 130 is connected to the other end of the winding of each phase. In this specification, "connection" of components (structural elements) to each other mainly means electrical connection.

The 1 st inverter 120 has terminals a _ L, B _ L and C _ L corresponding to the respective terminals. The 2 nd inverter 130 has terminals a _ R, B _ R and C _ R corresponding to each. The terminal a _ L of the 1 st inverter 120 is connected to one end of the winding M1 of the a phase, the terminal B _ L is connected to one end of the winding M2 of the B phase, and the terminal C _ L is connected to one end of the winding M3 of the C phase. Similarly to the 1 st inverter 120, the terminal a _ R of the 2 nd inverter 130 is connected to the other end of the a-phase winding M1, the terminal B _ R is connected to the other end of the B-phase winding M2, and the terminal C _ R is connected to the other end of the C-phase winding M3.

The power supply has a 1 st power supply 410 supplying power to the 1 st inverter 120 and a 2 nd power supply 420 supplying power to the 2 nd inverter 130. The respective power supply voltages of the 1 st power supply 410 and the 2 nd power supply 420 are, for example, 12V, 16V, 24V, or 48V. As the power supply, for example, a direct current power supply is used. However, the power source may be an AC-DC converter or a DC-DC converter, or may be a battery (secondary battery). Alternatively, one power source common to the 1 st and 2

nd inverters

120 and 130 may be used.

A coil 102 is provided between the 1 st power source 410 and the 1 st inverter 120. A coil 102 is provided between the 2 nd power source 420 and the 2 nd inverter 130. The coil 102 functions as a noise filter and smoothes the voltage waveform supplied to each inverter so that high-frequency noise included in the voltage waveform or high-frequency noise generated in each inverter does not flow out to the power supply side.

A capacitor 103 is connected to a power supply terminal of each inverter. The capacitor 103 is a so-called bypass capacitor, and suppresses voltage ripples. The capacitor 103 is, for example, an electrolytic capacitor, and the capacity and the number of capacitors to be used are appropriately determined in accordance with design specifications and the like.

The 1 st inverter 120 has a bridge circuit including three legs. Each branch has a low-side switching element and a high-side switching element. The a-phase branch has a low-side switching element 121L and a high-side switching element 121H. The B-phase leg has a low-side switching element 122L and a high-side switching element 122H. The C-phase leg has a low-side switching element 123L and a high-side switching element 123H. As the switching element, for example, a field effect transistor (typically, MOSFET) or an Insulated Gate Bipolar Transistor (IGBT) can be used. Hereinafter, an example in which a MOSFET is used as a switching element will be described, and the switching element may be referred to as SW. For example, the low-

side switching elements

121L, 122L, and 123L are denoted as

SW

121L, 122L, and 123L.

The 1 st inverter 120 includes three

shunt resistors

121R, 122R, and 123R included in a current sensor 150, and the current sensor 150 detects a current flowing through a winding of each of the a, B, and C phases. The current sensor 150 includes a current detection circuit (not shown) that detects a current flowing through each shunt resistor. For example, the

shunt resistors

121R, 122R, and 123R are connected between three low-side switching elements included in the three branches of the 1 st inverter 120 and GND, respectively. Specifically, the shunt resistor 121R is electrically connected between the SW 121L and the GND, the shunt resistor 122R is electrically connected between the SW 122L and the GND, and the shunt resistor 123R is electrically connected between the SW 123L and the GND. The shunt resistor has a resistance value of, for example, about 0.5m Ω to 1.0m Ω.

Like the 1 st inverter 120, the 2 nd inverter 130 has a bridge circuit including three legs. The a-phase branch has a low-side switching element 131L and a high-side switching element 131H. The B-phase branch has a low-side switching element 132L and a high-side switching element 132H. The C-phase leg has a low-side switching element 133L and a high-side switching element 133H. Further, the 2 nd inverter 130 has three

shunt resistors

131R, 132R, and 133R included in the current sensor 150. These shunt resistors are connected between the three low-side switching elements included in the three branches and GND.

The number of shunt resistors is not limited to three for each inverter. For example, two shunt resistors for a phase and B phase, two shunt resistors for B phase and C phase, and two shunt resistors for a phase and C phase may be used. The number of shunt resistors used and the arrangement of the shunt resistors are appropriately determined in consideration of product cost, design specifications, and the like.

The number of switching elements to be used is not limited to the illustrated example, and is determined as appropriate in consideration of design specifications and the like. In particular, in the field of vehicle mounting, it is desirable to provide a plurality of switching elements used in each inverter in advance because it is required to ensure high quality from the viewpoint of safety.

As described above, the 2 nd inverter 130 has substantially the same configuration as that of the 1 st inverter 120. In fig. 2, for convenience of explanation, the inverter on the left side of the drawing is referred to as a 1 st inverter 120, and the inverter on the right side is referred to as a 2 nd inverter 130. However, such expressions should not be construed as limiting the present disclosure. The terms "1 st inverter 120" and "2 nd inverter 130" can be used as the structural elements of the power conversion apparatus 100 without distinction.

The block structure around the 1 st control circuit 314 in the 1 st motor control device 310 will be described with reference to fig. 3. The motor control is performed by the block structure of the 2 nd motor control device 320, which is substantially the same as the block structure of the 1 st motor control device 310, and therefore, the description thereof is omitted.

Fig. 3 shows an exemplary block structure of the 1 st motor control device 310. The 1 st motor control device 310 includes, for example, a 1 st power supply circuit 311, an angle sensor 312, an input circuit 313, a 1 st control circuit 314, a 1 st drive circuit 315, and a ROM 319. The angle sensor 312 is a sensor common to the 1 st motor control device 310 and the 2 nd motor control device 320. However, as the angle sensor 312, an angle sensor for the 1 st motor control device 310 and an angle sensor for the 2 nd motor control device 320 may be provided, respectively.

The 1 st motor control device 310 is connected to the 1 st inverter 120 of the power conversion device 100. The 1 st motor control device 310 controls switching operations of the plurality of switching elements of the 1 st inverter 120. Specifically, the 1 st motor control device 310 generates a control signal (hereinafter, referred to as a "gate control signal") for controlling the switching operation of each SW, and outputs the control signal to the 1 st inverter 120. The 2 nd motor control device 320 is connected to the 2 nd inverter 130. The 2 nd motor control device 320 generates a gate control signal and outputs it to the 2 nd inverter 130.

The motor control device can control the position, the rotation speed, the current, and the like of the rotor of the motor 200 as a target to realize closed-loop control. In addition, the motor control device may have a torque sensor instead of the angle sensor 312. In this case, the motor control device can control the target motor torque.

The 1 st power supply circuit 311 generates a DC voltage (for example, 3V or 5V) necessary for each block in the circuit. The 1 st power supply circuit 311 is different from a power system power supply circuit described later.

The angle sensor 312 is, for example, a resolver or a hall IC. Alternatively, the angle sensor 312 can also be realized by a combination of an MR sensor having a Magnetoresistive (MR) element and a sensor magnet. The angle sensor 312 detects a rotation angle of the rotor (hereinafter referred to as a "rotation signal"), and outputs the rotation signal to the 1 st control circuit 314 and the 2 nd control circuit 324 of the 2 nd motor control device 320 (see fig. 5).

The input circuit 313 receives a motor current value (hereinafter referred to as "actual current value") detected by the

shunt resistors

121R, 122R, and 123R of the current sensor 150, converts the level of the actual current value to an input level of the 1 st control circuit 314 as necessary, and outputs the actual current value to the 1 st control circuit 314. The input circuit 313 is, for example, an analog-digital conversion circuit.

The 1 st control circuit 314 is an integrated circuit that controls the 1 st inverter 120, and is, for example, a microcontroller or an FPGA (Field Programmable Gate Array).

The 1 st control circuit 314 controls the switching operation (on or off) of each SW of the 1 st inverter 120 of the power conversion device 100. The 1 st control circuit 314 sets a target current value based on an actual current value, a rotor rotation signal, and the like, generates a PWM signal, and outputs the PWM signal to the 1 st drive circuit 315.

The 1 st driving circuit 315 is typically a gate driver (or pre-driver). The 1 st drive circuit 315 generates a gate control signal from the PWM signal, and applies the control signal to the gate of the switching element of the 1 st inverter 120. When the driving target is a motor that can be driven at a low voltage, the driving target may not be a gate driver. In this case, the function of the gate driver can be mounted on the 1 st control circuit 314.

The ROM319 is electrically connected to the 1 st control circuit 314. The ROM319 is, for example, a writable memory (e.g., PROM), a rewritable memory (e.g., flash memory), or a read-only memory. The ROM319 stores a control program including instruction sets for causing the 1 st control circuit 314 to control the power conversion apparatus 100. For example, the control program is loaded once in a RAM (not shown) at the time of startup.

Fig. 4 is a schematic diagram showing the configuration of the motor module 1000. Fig. 4 shows a cross section of the motor module 1000 when the yz plane in the drawing is cut along the center axis 211.

The motor module 1000 includes a stator 220, a rotor 230, a housing 212, a bearing holder 214, a bearing 215, and a bearing 216. The stator 220 is also referred to as an armature. The central axis 211 is the rotational axis of the rotor 230.

The housing 212 is a substantially cylindrical case with a bottom, and houses the stator 220, the bearing 215, and the rotor 230 therein.

The bearing holder 214 partitions a space for accommodating the stator 220 and the rotor 230 and a space for accommodating the two substrates (the 1 st and 2 nd substrates) CB1 and CB2 in the motor module 1000. The bearing holder 214 is a plate-like member, and holds a bearing 216 at a central portion thereof.

Stator 220 is annular and includes a laminated body 222 and a winding 221. The laminated body 222 is also referred to as a laminated annular core. The windings are also called coils. The stator 220 generates magnetic flux according to the driving current. The laminated body 222 is formed of laminated steel plates in which a plurality of steel plates are laminated in a direction along the central axis 211 (z direction in fig. 4). The stacked body 222 is fixed to the inner wall of the case 212.

The winding 221 is made of a conductive material such as copper, and is typically attached to each of a plurality of teeth (not shown) of the laminate 222.

The rotor 230 includes a shaft 233, a rotor core 231, and a plurality of permanent magnets 232 provided along the outer periphery of the rotor core 231. The rotor core 231 is made of a magnetic material such as iron, and has a cylindrical shape. In the present embodiment, the rotor core 231 is formed of a laminated steel plate in which a plurality of steel plates are laminated in a direction along the center axis 211 (z direction in fig. 4). The plurality of permanent magnets 232 are arranged such that N poles and S poles alternately appear in the circumferential direction of the rotor core 231. The shaft 233 is fixed to the center of the rotor core 231 and extends in the vertical direction (z direction) along the center axis 211. Note that the vertical and horizontal directions in this specification refer to vertical and horizontal directions when the motor module 1000 shown in fig. 4 is viewed, and for convenience of understanding, the description will be made using these directions. The vertical and horizontal directions in this specification do not necessarily coincide with the vertical and horizontal directions in a state where the motor module 1000 is mounted on an actual product (such as an automobile).

The

bearings

215 and 216 support a shaft 233 of the rotor 230 so that the shaft 233 can rotate. The

bearings

215 and 216 are, for example, ball bearings in which an outer race and an inner race are relatively rotated by balls.

In the motor module 1000, when a drive current is applied to the winding 221 of the stator 220, a radial magnetic flux is generated in the plurality of teeth of the stacked body 222. A torque is generated in the circumferential direction by the action of the magnetic flux between the plurality of teeth and the permanent magnet 232, and the rotor 230 rotates relative to the stator 220. When the rotor 230 rotates, a driving force is generated in the EPS device, for example.

For example, a permanent magnet (not shown) is fixed to the end of the shaft 233 on the bearing holder 214 side. The permanent magnet can rotate together with the rotor 230. A magnetic sensor (not shown) corresponding to the angle sensor 312 is disposed at a position facing the permanent magnet fixed to the shaft 233 on the substrate CB1, for example. The magnetic sensor may be mounted on a substrate other than the substrate CB1 or the substrate CB 2. The magnetic sensor detects a magnetic field generated from the permanent magnet rotating together with the shaft 233, thereby being able to detect the rotation angle of the rotor 230.

Two substrates are disposed on the upper portion of the bearing holder 214. The coil 102 for the 1 st inverter 120, the capacitor 103, the 1 st inverter 120, and the electronic components of the 1 st motor control device 310, and the like are mounted on the board CB 1. The coil 102 for the 2 nd inverter 130, the capacitor 103, the 2 nd inverter 130, and the electronic components of the 2 nd motor control device 320, and the like are mounted on the substrate CB 2. The component groups of the motor module 1000 can be mounted on one or both surfaces of each substrate. The upper opening of the housing 212 is closed by a cover 250.

(embodiment mode 1)

In this embodiment, a case where the power supply voltages of the 1 st power supply 410 and the 2 nd power supply 420 are equal to each other and the power supply voltages are 12V will be described.

Fig. 5 shows a block structure of the motor control device of the present embodiment. The 1 st motor control device 310 includes a 1 st power supply circuit 311, a 1 st control circuit 314, and a 1 st drive circuit 315. The 1 st power supply circuit 311, the 1 st control circuit 314, and the 1 st drive circuit 315 are mounted on the substrate CB 1. The 1 st connector 316 is a separate component from the board CB 1. The board CB1 is connected to the 1 st power supply 410 via the 1 st connector 316.

A power supply voltage of 12V is supplied from the 1 st power supply 410 to the 1 st inverter 120. The 1 st power supply circuit 311 generates a DC voltage (for example, 3V) necessary for the 1 st control circuit 314, the 1 st drive circuit 315, and the like by stepping down the power supply voltage 12V of the 1 st power supply 410. The 1 st control circuit 314 outputs a PWM signal to the 1 st drive circuit 315. The 1 st drive circuit 315 generates a gate control signal from the PWM signal and supplies the gate control signal to each switching element of the 1 st inverter 120.

The 2 nd motor control device 320 has a 2 nd power supply circuit 321, a 2 nd control circuit 324, and a 2 nd drive circuit 325. The 2 nd power supply circuit 321, the 2 nd control circuit 324, and the 2 nd drive circuit 325 are mounted on the substrate CB 2. The 2 nd connector 326 is a separate component from the board CB 2. The board CB2 is connected to the 2 nd power supply 420 via the 2 nd connector 326.

A power supply voltage of 12V is supplied from the 2 nd power supply 420 to the 2 nd inverter 130. The 2 nd power supply circuit 321 generates a DC voltage (for example, 3V) necessary for the 2 nd control circuit 324, the 2 nd drive circuit 325, and the like by stepping down the power supply voltage 12V of the 2 nd power supply 420. The 2 nd control circuit 324 outputs the PWM signal to the 2 nd drive circuit 325. The 2 nd drive circuit 325 controls the gate of the signal in accordance with the PWM signal and supplies the signal to each switching element of the 2 nd inverter 130.

The connection between the 1 st power source 410 and the 1 st connector 316 and the connection between the 2 nd power source 420 and the 2 nd connector 326 are generally performed using a wire harness (not shown). A power loss (or voltage drop) caused by the wire harness is generated in a current path from the power source to the motor. For example, the resistance value of a wire harness used in the EPS system is about 15m Ω to 20m Ω. This is larger than the resistance value of the motor or ECU, and the power loss cannot be ignored. For example, when the power supply current is 100A at maximum, the voltage drop in the wire harness is about 1.5V to 2.0V, which cannot be ignored for a 12V power supply. Therefore, if the power loss of the wire harness can be improved, a high output of the motor can be expected.

In the present embodiment, the 1 st power supply 410 and the 2 nd power supply 420 of two systems are used, and thus a necessary current can be supplied to the motor 200 from two harnesses. Here, it is considered to use the power supplies of the two systems to supply the same current as the current flowing in the motor in the case where the power supplies are supplied to the two substrates using a single power supply. In this case, half of the current may flow through each wire harness, and therefore the diameter of the wire harness can be reduced. As a result, the power loss in the wire harness can be improved to about 1/4.

When the TN characteristics of the motor are observed, it is difficult to obtain a sufficient output (or torque) at the time of high-speed rotation of the motor when a single power supply is used. On the other hand, according to the present embodiment, since the efficiency indicating the ratio of the output power to the input power can be improved by reducing the power loss in the wire harness, it is possible to obtain a high output when the motor rotates at a high speed.

Fig. 6 shows another block structure of the motor control device of the present embodiment. Fig. 7 shows an example of the circuit configuration of the booster circuit.

Switch RL and boost circuit 1 317 may be further mounted on board CB1, and switch RL and boost circuit 2 327 may be further mounted on board CB 2.

The 1 st voltage boosting circuit 317 and the 2 nd voltage boosting circuit 327 are, for example, voltage boosting chopper circuits, respectively. Fig. 7 shows a typical circuit configuration of the boost chopper circuit. The boost chopper circuit includes a semiconductor switch S, a diode D, a capacitor C, a coil L, and the like.

The 1 st booster circuit 317 can boost the power supply voltage 12V of the 1 st power supply 410 and output a boosted voltage (for example, 24V) to the 1 st inverter 120. The 2 nd booster circuit 327 can boost the power supply voltage 12V of the 2 nd power supply 420 and output a boosted voltage (for example, 24V) to the 2 nd inverter 130. The boost chopper circuit is appropriately determined according to the power supply connected to each substrate.

The switch RL is a semiconductor switch such as a thyristor, an analog switch IC, or a MOSFET having a parasitic diode formed therein, or a mechanical relay, for example. For example, switch RL of board CB1 switches the power supply path of inverter 1 120 under the control of control circuit 1 314. For example, the switch RL of the board CB2 switches the power supply path of the 2 nd inverter 130 under the control of the 2 nd control circuit 324.

For example, during normal driving, a power supply path of 12V from the 1 st power supply 410 to the 1 st inverter 120 is selected by the switch RL, and a power supply path of 12V from the 2 nd power supply 420 to the 2 nd inverter 130 is selected by the switch RL. At the time of high-speed rotation, a power supply path for supplying a boosted voltage of 24V from the 1 st booster circuit 317 to the 1 st inverter 120 is selected by the switch RL, and a power supply path for supplying a boosted voltage of 24V from the 2 nd booster circuit 327 to the 2 nd inverter 130 is selected by the switch RL. According to such a configuration, in the motor drive, since the high voltage can be supplied to each inverter by dynamically switching the switch RL at the time of high-speed rotation, high output can be obtained at the time of high-speed rotation.

Fig. 8 shows still another block structure of the motor control device of the present embodiment. Fig. 9 shows a circuit configuration example of the step-down circuit.

The power supply voltage of the 1 st power supply 410 and the 2 nd power supply 420 is not limited to 12V, and may be 24V or 48V, for example. The switch RL and the 1 st step-down circuit 318 may be further mounted on the board CB1, and the switch RL and the 2 nd step-down circuit 328 may be further mounted on the board CB 2.

The 1 st step-down circuit 318 and the 2 nd step-down circuit 328 are, for example, step-down chopper circuits, respectively. A representative circuit configuration of the step-down chopper circuit is shown in fig. 9. The step-down chopper circuit is composed of a semiconductor switch S, a diode D, a capacitor C, a coil L, and the like.

For example, the 1 st step-down circuit 318 can step down the power supply voltage 24V of the 1 st power supply 410 and output the stepped-down voltage 12V to the 1 st inverter 120. The 2 nd step-down circuit 328 can step down the power supply voltage 24V of the 2 nd power supply 420 and output the stepped-down voltage 12V to the 2 nd inverter 130. The step-down chopper circuit is appropriately determined according to the power supply connected to each substrate.

For example, during normal driving, the switch RL selects a power supply path for supplying 12V of the stepped-down voltage from the 1 st step-down circuit 318 to the 1 st inverter 120, and the switch RL selects a power supply path for supplying 12V of the stepped-down voltage from the 2 nd step-down circuit 328 to the 2 nd inverter 130. At the time of high-speed rotation, a power supply path for supplying 24V from the 1 st power supply 410 to the 1 st inverter 120 is selected by the switch RL, and a power supply path for supplying 24V from the 2 nd power supply 420 to the 2 nd inverter 130 is selected by the switch RL. According to such a configuration, in the motor drive, since the high voltage can be supplied to each inverter by dynamically switching the switch RL at the time of high-speed rotation, high output can be obtained at the time of high-speed rotation.

Fig. 10 to 12 show the mounting of electronic components between the substrate CB1 and the substrate CB2 in the cross section of the motor module 1000 in the case of cutting along the central axis 211.

In one embodiment, as shown in fig. 10, a 1 st passive element group such as a capacitor 103 and a coil 102 (not shown in fig. 10) is mounted on a substrate CB 1. A 1 st motor control device 310 that controls switching operations of the plurality of switching elements of the 1 st inverter 120 is also mounted on the mounting surface of the capacitor 103 on the board CB 1. A 1 st power device group constituting the 1 st inverter 120 is mounted on a surface of the board CB1 on the opposite side to the mounting surface of the capacitor 103. Fig. 10 illustrates the 1 st control circuit 314 among the components of the 1 st motor control device 310, and illustrates two power devices (FETs) among the components of the 1 st power device group. The power device is a switching element SW of the inverter. Of course, the configuration elements of the 1 st power device group and the capacitor 103 may be arranged at positions that do not overlap when the substrate is seen in a direction along the central axis 211 without being limited to the illustrated example.

A 2 nd passive element group such as a capacitor 103 and a coil 102 (not shown in fig. 10) is mounted on the substrate CB 2. A 2 nd motor control device 320 for controlling switching operations of the plurality of switching elements of the 2 nd inverter is further mounted on the mounting surface of the capacitor 103 on the board CB 2. A 2 nd power device group constituting the 2 nd inverter 130 is mounted on a surface of the board CB2 on the opposite side to the mounting surface of the capacitor 103. Fig. 10 illustrates the 1 st control circuit 314 among the components of the 2 nd motor control device 320, and illustrates two power devices among the components of the 2 nd power device group.

The capacitor 103 in the 1 st passive element group and the capacitor 103 in the 2 nd passive element group are arranged between the substrate CB1 and the substrate CB2, and do not overlap each other when viewed along the central axis 211 (z direction of fig. 10). In the present embodiment, since the power supply voltages of the 1 st power supply 410 and the 2 nd power supply 420 are equal to each other, the same capacitor can be used as the capacitor 103 mounted on the board CB1 and the capacitor 103 mounted on the board CB 2. In this case, the heights of the capacitors 103 of the two substrates are the same.

The motor module 1000 may further include a 1 st heat sink 511, and the 1 st heat sink 511 is in thermal contact with the substrate CB1 via a heat dissipation material having insulation properties, for example, a heat dissipation grease. The 1 st heat sink 511 covers the 1 st power device group of the substrate CB 1. In the present specification, "thermal contact with the substrate" means a state in which the heat sink covers all or a part of the plurality of electronic components mounted on one surface of the substrate. The heat sink may not necessarily be in surface contact with the substrate.

As the 1 st heat sink 511, for example, a material having a good thermal conductivity such as aluminum can be used. For example, the 1 st heat sink 511 may be a cage of the housing 212 or a bearing cage 214. Alternatively, the 1 st heat sink 511 may be a component different from these components. By cooling the board CB1 with the 1 st heat sink 511, the heat radiation performance of the motor module 1000 can be improved.

In one aspect, as shown in fig. 11, the motor module 1000 further includes a 2 nd heat sink 512, and the 2 nd heat sink 512 is disposed between the substrate CB1 and the substrate CB2, and is in thermal contact with both substrates via a heat dissipating grease, for example. The 2 nd heat sink 512 has a recess covering the capacitor 103. By covering the capacitor, which generates heat particularly in the mounted components, with the 2 nd heat sink 512, heat can be efficiently dissipated. In this way, by cooling the board CB1 and the board CB2 using the 2 nd heat sink 512, the heat radiation performance of the motor module 1000 can be further improved.

In one embodiment, as shown in fig. 11, the 1 st motor controller 310 is mounted on a surface of the board CB1 opposite to the mounting surface of the capacitor 103, and the 2 nd motor controller 320 is mounted on a surface of the board CB2 opposite to the mounting surface of the capacitor 103. Fig. 11 illustrates the 1 st control circuit 314 among the components of the 1 st motor control device 310, and illustrates the 2 nd control circuit 324 among the components of the 2 nd motor control device 320.

In one embodiment, as shown in fig. 12, a 1 st power device group constituting a 1 st inverter 120 is further mounted on the mounting surface of the capacitor 103 of the board CB1, and a 2 nd power device group constituting a 2 nd inverter 130 is further mounted on the mounting surface of the capacitor 103 of the board CB 2. For example, the 1 st step-up circuit 317 or the 1 st step-down circuit 318 may be mounted on a surface of the substrate CB1 opposite to the mounting surface of the capacitor 103. In this case, the 1 st heatsink 511 has a concave portion covering the 1 st voltage boosting circuit 317 or the 1 st voltage dropping circuit 318. By covering and cooling the 1 st step-up circuit 317 or the 1 st step-down circuit 318, which generate much heat, with the 1 st heat sink 511, the heat radiation performance of the motor module 1000 can be improved.

Fig. 13 shows a circuit configuration of a modification of the power conversion device 100 of the present embodiment. In this modification, the power conversion apparatus 100 further includes two switching

elements

710 and 711. The switching element 710 switches between connection and disconnection between the node on the high side of the bridge circuit of the 1 st inverter 120 and the node on the high side of the bridge circuit of the 2 nd inverter 130. The switching element 711 switches between connection and disconnection between a node on the lower side of the bridge circuit of the 1 st inverter 120 and a node on the lower side of the bridge circuit of the 2 nd inverter 130. The two switching

elements

710 and 711 are semiconductor switches such as thyristors, analog switching ICs, MOSFETs having parasitic diodes formed therein, or mechanical relays, for example.

With this configuration, a zero-phase current can flow, and for example, two-phase current control can be performed. For example, when a fault occurs in the branch of the a-phase, the windings M2 and M3 of the two phases, B and C, can be used for conduction. For example, the two-phase energization control is described in international publication No. 2017/150638 of the applicant's patent application. For reference, these disclosures are incorporated in their entirety into the present specification. When one of the 1 st power supply 410 and the 2 nd power supply 420 fails, the three-phase energization control for energizing the three-phase windings can be continued using the other.

For example, the wiring of the motor can be switched to the Y wiring using the 1 st drive circuit 315 or the 2 nd drive circuit 325. In normal driving, the wiring of the motor is, for example, FHB wiring as shown in fig. 2 or fig. 13. After the wiring of the motor 200 is switched from the FHB wiring to the Y wiring, it is preferable to drive the Y-wired motor 200 with a power supply voltage twice as large as the power supply voltage used in the FHB wiring. For example, a power supply voltage of 12V is used for FHB wiring driving, and a power supply voltage of 24V is used for Y wiring driving. Thus, even when the connection of the motor 200 is switched from FHB connection to Y connection, the maximum rotation speed of the motor 200 can be maintained.

For example, when the high-side switching element 121H of the 1 st inverter 120 has an open failure, the connection of the motor can be switched to the Y connection. The 1 st drive circuit 315 outputs the following control signals: the remaining high-

side switching elements

122H, 123H are always turned off, and the three low-

side switching elements

121L, 122L, and 123L are always turned on. As a result, the 1 st inverter 120 forms a neutral point. In this state, the 2 nd motor control device 320 can PWM-control the switching elements of the 2 nd inverter 130. The 2 nd power supply 420 may be used when switching to the Y connection, or another power supply different from the 1 st power supply 410 or the 2 nd power supply 420 may be used.

When the power supply voltages of the 1 st power supply 410 and the 2 nd power supply 420 are made equal as in the present embodiment, no zero-phase current flows through each phase in the FHB connection. Therefore, when a motor having a large mutual inductance, for example, an 8-pole 12-slot (8P12S) is connected to and driven by the FHB-type power conversion apparatus 100, current noise caused by switching of the switching elements of the 1 st and 2

nd inverters

120 and 130 can be suppressed.

(embodiment mode 2)

In the present embodiment, the power supply voltage of the 1 st power supply 410 is different from the power supply voltage of the 2 nd power supply 420, which is different from embodiment 1. Hereinafter, differences from embodiment 1 will be mainly described.

Fig. 14 shows a block structure of the motor control device of the present embodiment. The power supply voltage of the 1 st power supply 410 is higher than the power supply voltage of the 2 nd power supply 420. For example, the power supply voltage of the 1 st power supply 410 is 48V, and the power supply voltage of the 2 nd power supply 420 is 12V. A power system power supply circuit that steps down or steps up the power supply voltage of the 1 st power supply 410 is mounted on the board CB 1. The 1 st step-down circuit 318 is illustrated in fig. 14 as a power system power supply circuit. For example, the 1 st step-down circuit 318 steps down the power supply voltage 48V of the 1 st power supply 410 and outputs the stepped-down voltage 12V to the 1 st inverter 120 via the switch RL.

According to this configuration, when the three-phase energization control of the FHB is performed, the stepped-down voltage 12V output from the 1 st step-down circuit 318 is supplied to the 1 st inverter 120, and the power supply voltage 12V of the 2 nd power supply 420 is supplied to the 2 nd inverter 130. Further, for example, by switching the motor connection on the 2 nd inverter 130 side to the Y connection using the 2 nd drive circuit 325 as described above, the switching elements of the 1 st inverter 120 can be PWM-controlled using the power supply voltage 48V of the 1 st power supply.

Fig. 15 shows another block structure of the motor control device of the present embodiment. For example, a 2 nd booster circuit 327 may be mounted on the board CB2, and the 2 nd booster circuit 327 boosts the power supply voltage 12V of the 2 nd power supply 420 and outputs a boosted voltage 24V to the 2 nd inverter 130. The 1 st step-down circuit 318 can generate a step-down voltage of 24V or 12V.

According to this configuration example, during normal driving, for example, 12V is supplied from the 1 st step-down circuit 318 to the 1

st inverter

120, and 12V is supplied from the 2 nd power supply to the 2 nd inverter 130, whereby three-phase energization control of FHB can be performed using 12V. On the other hand, at the time of high-speed rotation, for example, by supplying the step-down voltage 24V from the 1 st step-down circuit 318 to the 1 st inverter 120 and supplying the step-up voltage 24V from the 2 nd step-up circuit 327 to the 2 nd inverter 130, the three-phase conduction control of FHB can be performed using 24V. In the motor drive, since the high voltage can be supplied to each inverter by dynamically switching the switch RL at the time of high-speed rotation, high output can be obtained at the time of high-speed rotation.

For example, consider the case where the motor module 1000 is mounted to the EPS. In this case, for example, even if the 1 st power supply 410 fails, the steering force can be maintained by switching the power supply to the 2 nd power supply 420 and using the boosted voltage of the 2 nd booster circuit 327 of the board CB 2.

Fig. 16 and 17 show the mounting of electronic components between the substrate CB1 and the substrate CB2 in the cross section of the motor module 1000 with a cut along the central axis 211.

The 1 st passive element group is mounted on the board CB1, and the 2 nd passive element group is mounted on the board CB 2. Among the passive element groups composed of coils, resistors, capacitors, and the like, the elements with the highest height are typically capacitors. In the present embodiment, the 1 st passive element with the highest height on the substrate CB1 is the capacitor 103_1H, and the 2 nd passive element with the highest height on the substrate CB2 is the capacitor 103_ 2H. In general, the higher the power supply voltage, the more a capacitor having a larger capacity is required as the capacitor 103. As a result, the capacitor 103 mounted on the board CB1 needs to have a larger capacity than the capacitor 103 mounted on the board CB 2. Therefore, the size of the capacitor 103_1H is larger than the size of the capacitor 103_2H, and specifically, the height of the capacitor 103_1H is higher than the height of the capacitor 103_ 2H.

In the present embodiment, the capacitor 103_1H with the highest height in the 1 st passive element group and the capacitor 103_2H with the highest height in the 2 nd passive element group are arranged between the substrate CB1 and the substrate CB2, and do not overlap each other when viewed in the direction of the central axis 211. As a result, the two capacitors 103_1H and 103_2H do not overlap with each other in the direction of the central axis 211, and therefore the height of the motor module 1000 can be suppressed, and a motor module having a lower height can be realized. Let the height of the capacitor 103_1H be H1, and the height of the capacitor 103_2H be H2(≦ H1). If two capacitors are stacked in the direction of the central axis 211 as in the conventional case, the total height is h1+ h 2. In contrast, if two capacitors are arranged as shown in fig. 16, two capacitors can be arranged within the range of the height h 1.

The motor module 1000 may also have a 1 st heat sink 511 in thermal contact with the substrate CB1, for example via a thermal grease. For example, the 1 st heat sink 511 may be a cage of the housing 212 or a bearing cage 214. Alternatively, the 1 st heat sink 511 may be a component different from these components.

For example, the 1 st step-down circuit 318 may be mounted on a surface of the substrate CB1 on the opposite side to the mounting surface of the capacitor 103_ 1H. The rotor 230, the 1 st heat sink 511, the substrate CB1, and the substrate CB2 are arranged in this order along the rotation axis of the rotor 230 of the motor 200, that is, in the direction of the center axis 211. In particular, the 1 st step-down circuit 318 as the power system power supply circuit generates a large amount of heat. By covering the 1 st step-down circuit 318 with the 1 st heat sink 511, the 1 st step-down circuit 318 can be cooled, and the heat radiation performance of the motor module 1000 can be improved.

In one aspect, as shown in fig. 16, the motor module 1000 further includes a 2 nd heat sink 512, and the 2 nd heat sink 512 is disposed between the substrate CB1 and the substrate CB2, and is in thermal contact with both substrates via a heat dissipating grease, for example. According to this configuration, by cooling the board CB1 and the board CB2 by the 2 nd heat sink 512, the heat radiation performance of the motor module 1000 can be further improved.

In one embodiment, as shown in fig. 17, the motor module 1000 further includes a 2 nd heat sink 512, and the 2 nd heat sink 512 covers a surface of the substrate CB2 on the opposite side to the mounting surface of the capacitor 103_ 2H. The rotor 230, the 1 st heat sink 511, the substrate CB1, the substrate CB2, and the 2 nd heat sink 512 are arranged in this order along the rotation axis of the rotor 230 of the motor 200, that is, in the direction of the center axis 211. According to such an arrangement, since the 2 nd heat sink 512 is positioned on the cover 250 side of the motor module 1000, it is easy to expose it to the outside, and the heat radiation performance of the motor module 1000 can be improved. As shown in fig. 16, another heat sink may be disposed between the board CB1 and the board CB2 as the 3 rd heat sink.

The thermal resistance of the 1 st heatsink 511 is preferably less than that of the 2 nd heatsink 512. For example, the 1 st heat sink 511 has a larger volume than the 2 nd heat sink 512.

The cover 250 of the motor module 1000 can function as the 2 nd heat sink 512. Alternatively, the 2 nd heat sink 512 may be another component independent from the cover 250. The size of the 2 nd heat sink 512 can be made smaller than the size of the 1 st heat sink 511, and the number of components of the motor module 1000 can be reduced.

In some manner, the supply voltage of the 1 st power supply 410 may also be lower than the supply voltage of the 2 nd power supply 420. For example, the power supply voltage of the 1 st power supply 410 may be 12V, and the power supply voltage of the 2 nd power supply 420 may be 48V. In this case, the 1 st booster circuit 317 as a power system power supply circuit may be mounted on the board CB 1. For example, the 1 st booster circuit 317 boosts the power supply voltage 12V of the 1 st power supply and outputs the boosted voltage of 24V to the 1 st inverter 120 via the switch RL. In this configuration, in particular, the heat generation of the 1 st booster circuit 317 as the power system power supply circuit becomes large. By covering the 1 st booster circuit 317 with the 1 st heat sink 511, the 1 st booster circuit 317 can be cooled, and the heat radiation performance of the motor module 1000 can be improved. For example, a 2 nd step-down circuit 328 may be mounted on the board CB2, and the 2 nd step-down circuit 328 steps down the power supply voltage 48V of the 2 nd power supply 420 and outputs a 24V stepped-down voltage to the 2 nd inverter 130 via the switch RL.

In one mode, the shape of the base plate CB1 AS viewed in the direction of the central axis 211 is the same AS the shape of the base plate CB2, the base plate CB1 and the base plate CB2 having a common axis of symmetry AS. The shape of the substrate is, for example, circular, elliptical or polygonal. As the substrate CB1 and the substrate CB2, the same substrate can be used. An example of mounting the electronic component on the board CB1 of the two boards will be described below.

Fig. 18A and 18B illustrate a case where electronic components are mounted on both surfaces of the board CB 1. Fig. 19 shows the arrangement in the z-axis direction of the substrate CB1 and the substrate CB2 in the motor module 1000. Fig. 18A shows a mounting surface S1 of the substrate CB1 on which the capacitor 103 is mounted, when viewed from the + z direction along the rotation axis of the rotor 230, i.e., the direction of the center axis 211. Fig. 18B shows the mounting surface S2 of the board CB1 on the side opposite to the mounting surface S1 as viewed from the-z direction along the direction of the central axis 211. However, in order to avoid the drawing from becoming complicated, only main electronic components that can be mounted on both sides are shown.

The base plate CB1 has an axis of symmetry AS and has line symmetry about the axis of symmetry AS. The board CB1 has a 1 st area AR1 (lower area of the paper) where the 1 st motor control device 310 is disposed, and a 2 nd area AR2 (upper area of the paper) where the 1 st passive element group and the 1 st power device group are disposed. For example, the 1 st drive circuit 315 of the 1 st motor control device 310 is disposed in the 1 st region AR1 of the mounting surface S1, and the capacitor 103 and four FETs among six FETs constituting the 1 st inverter 120 are disposed in the 2 nd region AR 2. For example, the 1 st control circuit 314 of the 1 st motor control device 310 is disposed in the 1 st area AR1 of the mounting surface S2, and the remaining two FETs are disposed in the 2 nd area AR 2.

The base plate CB2 has an axis of symmetry AS and has line symmetry about the axis of symmetry AS. Similarly to the board CB1, the 3 rd region AR3 of the board CB2 is a region where the 2 nd motor control device 320 is mounted, and the 4 th region AR4 of the board CB2 is a region where the 2 nd passive element group and the 2 nd power device group are mounted. AS shown in fig. 19, the board CB2 is disposed in the motor module 1000 turned 180 ° with respect to the board CB1 with reference to the symmetry axis AS. Thus, when the motor module 1000 is viewed in the direction along the central axis 211 (z axis of fig. 19), the 1 st area AR1 and the 4 th area AR4 of the substrate CB2 coincide, and the 2 nd area AR2 and the 3 rd area AR3 of the substrate CB2 coincide.

With this configuration, the heat radiation paths of the board CB1 and the board CB2 do not overlap in the direction of the central axis 211, and therefore the respective boards can be efficiently radiated. When the board CB1 and the board CB2 are arranged in the direction of the center axis 211, the elements can be arranged symmetrically with respect to the symmetry axis AS. Since the elements of the board CB1 and the board CB2 are arranged in the same manner, the board CB1 may be superposed on the board CB2 during assembly. In this way, the same board design is adopted for the board CB1 and the board CB2, and the number of design steps can be reduced. Further, as described above, the two capacitors 103_1H and 103_2H do not overlap in the direction of the central axis 211, and therefore the height of the motor module 1000 can be suppressed, and a motor module having a lower height can be realized. Further, by disposing the 2 nd heat sink 512 between the board CB1 and the board CB2, heat can be efficiently dissipated to each board.

According to the present disclosure, even if at least one of the switching elements in the power supply system and the power conversion device 100 fails, the motor output can be maintained and the motor drive can be continued.

(other modification example)

The structure or arrangement of the substrate of the motor module 1000 described in this specification can be suitably used for a motor module having a dual inverter structure. In the double inverter structure, the windings M1, M2, and M3 of the three phases have the 1 st and 2 nd winding groups with one ends Y-wired to each other. The 1 st inverter 120 is connected to the 1 st winding group, and the 2 nd inverter 130 is connected to the 2 nd winding group.

In this specification, the motor module 1000 connected to the power supplies of two systems is explained, but a single power supply of one system may be used. For example, in a general case, a power supply voltage of 12V is supplied from a single power supply to the substrate CB1 and the substrate CB 2. When the power supply fails, for example, the two substrates may be connected to another power supply in a standby state, and a 12V power supply may be supplied from the power supply to the two substrates. Such power supply systems are also within the scope of the present disclosure. With this configuration, the motor drive by FHB wiring can be continued.

The motor module 1000 may also include a voltage divider circuit (not shown) connecting the board CB1 and the board CB 2. According to this configuration, even when one of the power supplies of the two systems fails, the motor drive can be continued using the other. In this way, one power source can be branched off the other.

In the present specification, an embodiment using two substrates is described, but a plurality of three or more substrates may be used. For example, the following four substrates can be used: (1) a substrate CB1 on which the 1 st motor control device 310 is disposed and a substrate CB2 on which the 1 st group of passive elements and the 1 st group of power devices are disposed, which are connected to the 1 st power source 410, and (2) a 3 rd substrate on which the 2 nd motor control device 320 is disposed and a 4 th substrate on which the 2 nd group of passive elements and the 2 nd group of power devices are disposed, which are connected to the 2 nd power source 420.

(embodiment mode 3)

Fig. 20 schematically shows a typical configuration of an electric power steering apparatus 3000 according to the present embodiment.

Vehicles such as automobiles generally have an electric power steering apparatus. The electric power steering apparatus 3000 of the present embodiment includes a steering system 520 and an assist torque mechanism 540 that generates an assist torque. The electric power steering apparatus 3000 generates an assist torque that assists a steering torque of a steering system generated by a driver operating a steering wheel. The operation burden on the driver is reduced by the assist torque.

The steering system 520 includes, for example, a steering wheel 521, a steering shaft 522,

universal joints

523A and 523B, a rotating shaft 524, a rack-and-pinion mechanism 525, a rack shaft 526, left and right ball joints 552A and 552B,

tie rods

527A and 527B,

knuckles

528A and 528B, and left and right steered

wheels

529A and 529B.

The assist torque mechanism 540 includes, for example, a steering torque sensor 541, an automotive Electronic Control Unit (ECU)542, a motor 543, and a speed reduction mechanism 544. The steering torque sensor 541 detects a steering torque in the steering system 520. ECU 542 generates a drive signal based on the detection signal of steering torque sensor 541. The motor 543 generates an assist torque corresponding to the steering torque based on the drive signal. The motor 543 transmits the generated assist torque to the steering system 520 via the speed reduction mechanism 544.

The ECU 542 is, for example, the motor control device of

embodiment

1 or 2. An electronic control system with an ECU as a core is built in an automobile. In the electric power steering apparatus 3000, for example, a motor drive unit is configured by the ECU 542, the motor 543, and the inverter 545. The motor module 1000 of

embodiment

1 or 2 can be suitably used for this unit.

Industrial applicability

Embodiments of the present disclosure can be widely applied to various apparatuses having various motors, such as a dust collector, a dryer, a ceiling fan, a washing machine, a refrigerator, and an electric power steering apparatus.

Claims

1. A motor module having:

a motor having n-phase windings, n being an integer of 3 or more;

a 1 st substrate connected to a 1 st power supply;

a 1 st inverter mounted on the 1 st substrate and connected to the n-phase winding;

a 1 st motor control device mounted on the 1 st substrate and controlling switching operations of a plurality of switching elements of the 1 st inverter;

a 2 nd substrate connected to a 2 nd power supply, the 2 nd power supply generating the same power supply voltage as the 1 st power supply;

a 2 nd inverter mounted on the 2 nd substrate and connected to the n-phase winding; and

and a 2 nd motor control device mounted on the 2 nd substrate and controlling switching operations of the plurality of switching elements of the 2 nd inverter.

2. The motor module of claim 1,

the 1 st inverter is connected to one end of a winding of each phase of the motor,

the 2 nd inverter is connected to the other end of the winding of each phase of the motor.

3. The motor module of claim 1 or 2,

the motor module also has a 1 st heat sink in thermal contact with the 1 st substrate.

4. The motor module of any one of claims 1 to 3,

the motor module further includes a 2 nd heat sink, and the 2 nd heat sink is disposed between the 1 st substrate and the 2 nd substrate and thermally contacts both substrates.

5. The motor module of any one of claims 1 to 4,

a 1 st booster circuit that boosts a power supply voltage of the 1 st power supply and outputs the boosted voltage to the 1 st inverter is further mounted on the 1 st substrate,

a 2 nd booster circuit that boosts a power supply voltage of the 2 nd power supply and outputs the boosted voltage to the 2 nd inverter is further mounted on the 2 nd substrate.

6. The motor module of any one of claims 1 to 5,

a 1 st step-down circuit that steps down a power supply voltage of the 1 st power supply and outputs the stepped-down voltage to the 1 st inverter is further mounted on the 1 st substrate,

a 2 nd step-down circuit that steps down a power supply voltage of the 2 nd power supply and outputs the stepped-down voltage to the 2 nd inverter is further mounted on the 2 nd substrate.

7. The motor module of any one of claims 2 to 6,

the motor module further has:

a 1 st switching element that switches between connection and disconnection between a node on the high side of the bridge circuit of the 1 st inverter and a node on the high side of the bridge circuit of the 2 nd inverter; and

and a 2 nd switching element for switching between connection and disconnection between a node on the lower side of the bridge circuit of the 1 st inverter and a node on the lower side of the bridge circuit of the 2 nd inverter.

8. The motor module of any one of claims 2 to 7,

the 1 st motor control device has a 1 st drive circuit and a 1 st control circuit for controlling the 1 st drive circuit,

the 2 nd motor control device has a 2 nd drive circuit and a 2 nd control circuit that controls the 2 nd drive circuit.

9. The motor module of claim 8,

the wiring of the motor can be switched to a Y wiring using the 1 st drive circuit or the 2 nd drive circuit.

10. The motor module of claim 9,

after the wiring of the motor is switched to the Y wiring, the motor is driven using a power supply voltage twice as high as a power supply voltage before the wiring of the motor is switched.

11. The motor module of any one of claims 1 to 10,

the power supply voltage of the 1 st power supply and the 2 nd power supply is 12V.

12. An electric power steering apparatus includes:

a 1 st power supply;

a 2 nd power supply; and

the motor module of any one of claims 1 to 11.