CN213484777U

CN213484777U - Position detection system for motor and vehicle

Info

Publication number: CN213484777U
Application number: CN202022176658.1U
Authority: CN
Inventors: 张凤娟; 梁岂源; 杜智勇; 张鑫鑫
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2020-09-28
Filing date: 2020-09-28
Publication date: 2021-06-18
Anticipated expiration: 2030-09-28

Abstract

The utility model discloses a position detecting system and vehicle of motor, position detecting system of motor includes: a position sensor; the first decoder is electrically connected with the position sensor; the controller is electrically connected with the first decoder through a bus; and the second decoder is electrically connected with the controller, and the second decoder is electrically connected with the first decoder through a connecting wire so as to transmit the electrical angle signal transmitted by the first decoder to the controller. The position detection system of the motor can realize the rapid and accurate reading of the rotation angle information of the motor shaft by arranging the two decoders.

Description

Position detection system for motor and vehicle

Technical Field

The utility model belongs to the technical field of the motor technique and specifically relates to a position detecting system and vehicle of motor are related to.

Background

For the control of the motor, for example, the position of the motor is controlled, and the controller needs to read the state of the position sensor at a specific time so as to obtain the information of the current rotation angle of the motor shaft. Typically, the position sensor employs a resolver to measure the degree of rotation of the motor shaft. Because the resolver outputs analog quantity and the controller receives digital quantity, a decoder is arranged between the controller and the resolver to realize the control of the controller on the motor, namely the measurement of the rotation angle of the motor shaft. Wherein, the chip of the decoder is a rotary change decoder chip or a processor chip with the same function. The rotary encoder chip and the controller may be connected via an SPI (Serial peripheral interface) bus, or other bus with equivalent functions.

However, in the related art, when the controller needs to obtain the rotation angle information of the motor shaft, it needs to send a specific command to the decoder chip through the SPI bus. The communication data based on the SPI generally consists of a plurality of bytes, and when the communication data is read through the SPI, the communication data needs to receive and transmit a plurality of bytes of data (8 bits per byte) through the SPI to obtain the current electrical angle information. The more the number of bytes transmitted and received is, the more bus transmission time is occupied, which causes system control delay and affects the improvement of control performance. Meanwhile, more CPU time is occupied, the requirement on the execution efficiency of the electronic control software is higher, and unnecessary development cost is generated.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, an object of the present invention is to provide a position detecting system for a motor, which can quickly read the rotation angle information of the motor shaft.

The utility model discloses a vehicle is further proposed.

According to the utility model discloses position detecting system of motor, include: a position sensor; a first decoder electrically connected to the position sensor; a controller electrically connected to the first decoder through a bus; the second decoder is electrically connected with the controller, and the second decoder is electrically connected with the first decoder through a connecting wire so as to transmit the electrical angle signal transmitted by the first decoder to the controller.

Therefore, the utility model discloses position detecting system of motor through setting up two decoders, can realize reading motor shaft rotation angle information fast, accurately.

According to some embodiments of the invention, the second decoder is integrated on the controller.

According to some embodiments of the invention, the controller is electrically connected with the second decoder through a connection line.

According to some embodiments of the utility model, be provided with bus interface on the controller, bus interface with the bus is connected, the second decoder is provided with the encoder interface, the decoder interface with the connecting wire is connected.

According to some embodiments of the invention, the position sensor is a rotary transformer.

According to some embodiments of the invention, the second decoder is an incremental decoder.

According to some embodiments of the present invention, the controller is any one of a single chip microcomputer, a single board computer, a microcomputer, and a PLC.

According to some embodiments of the invention, the bus is a SPI bus, a SCI bus, an IIC bus, or a UART bus.

According to some embodiments of the invention, the connecting line comprises three data transmission lines and all is electrically connected with the first decoder.

According to the utility model discloses a vehicle, include: a motor; the position detection system of the motor is characterized in that the position sensor is arranged on the motor.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic connection diagram of a position detection system of a motor according to an embodiment of the present invention;

fig. 2 is a flow chart of the operation of a position detection system for an electric machine according to an embodiment of the present invention;

fig. 3 is a schematic diagram of the signal change of the three-phase interface of the incremental decoder.

Reference numerals:

a detection system 100;

a position sensor 10; a first decoder 20; a controller 30; a second decoder 40; a bus 50; and connecting lines 60.

Detailed Description

Embodiments of the present invention are described in detail below, and the embodiments described with reference to the drawings are exemplary.

A position detection system 100 for an electric machine, which may be a permanent magnet synchronous machine, according to an embodiment of the present invention is described below with reference to fig. 1-3.

As shown in fig. 1, a position detecting system 100 for a motor according to an embodiment of the present invention includes: a position sensor 10, a first decoder 20, a controller 30 and a second decoder 40. The position sensor 10 is used to detect the angle information of the rotation of the motor shaft, i.e. the electrical angle, for example, the position sensor 10 may be a resolver, which is an electromagnetic sensor, also called a resolver, and is a small ac motor for measuring the angular displacement and angular velocity of the rotating shaft of a rotating object. The resolver may convert a physical quantity of the motor shaft rotation information into an analog quantity. Of course, the position sensor 10 may also be a hall sensor.

As shown in fig. 1, the first decoder 20 is electrically connected to the position sensor 10, the controller 30 is electrically connected to the first decoder 20 through a bus 50, the second decoder 40 is electrically connected to the controller 30, and the second decoder 40 is electrically connected to the first decoder 20 through a connection line 60 to transmit the electrical angle signal transmitted from the first decoder 20 to the controller 30. Since the controller 30 receives only a digital signal and the resolver outputs an analog signal, a decoder is provided between the controller 30 and the position sensor 10 for data mode conversion.

Particularly, the position detecting system 100 of the motor of the embodiment of the present invention includes two sets of circuit connections. The first set of circuits is: the controller 30 is electrically connected to the first decoder 20 through the bus 50, and the first decoder 20 is electrically connected to the position sensor 10. The second set of circuits is: the controller 30 is electrically connected to the second decoder 40, the second decoder 40 is electrically connected to the first decoder 20 through a connection line 60, and the first decoder 20 is electrically connected to the position sensor 10.

The first set of circuits is used for reading the initial electrical angle, and the second set of circuits is used for reading the current electrical angle on the basis of obtaining the initial electrical angle. Compared with the traditional detection system that has only used first set of circuit connection or has only used second set of circuit connection to detect the electric angle, the utility model discloses a position detecting system 100 of motor, combine first set of circuit and second set of circuit to use, in normal control process, the software directly reads the testing result of second set of circuit, avoid calling first set of circuit, thereby the control time of controller 30 has been saved, typically, it will spend 6 microseconds to call first set of circuit, and read only need 50 nanoseconds through second set of circuit connection, the time of saving can let the CPU of controller 30 do more tasks, be equivalent to under the unchangeable condition of chip cost who keeps controller 30, the performance software is bigger.

Therefore, the utility model discloses position detecting system 100 of motor through setting up two decoders, can realize reading motor shaft rotation angle information fast, accurately.

Optionally, the second decoder 40 is integrated on the controller 30. Integrating the second decoder 40 on the controller 30 can avoid providing a special space for placing the second decoder 40, and can also avoid arranging a line connection between the second decoder 40 and the controller 30, so that the whole detection system 100 can be more compact.

Alternatively, the controller 30 is electrically connected to the second decoder 40 through a connection line. That is, the second decoder 40 may be disposed at the periphery of the controller 30, i.e., the second decoder 40 is a peripheral device of the controller 30. The second decoder 40 is disposed at the periphery of the controller 30, and the second decoder 40 is electrically connected to the controller 30 through a connection line, so that the structure of the controller 30 can be simplified, and the mutual influence of the controller 30 and the second decoder 40 during operation can be reduced. For example, the second decoder 40 dissipates heat during operation, the controller 30 dissipates heat during operation, and the second decoder 40 is disposed at the periphery of the controller 30, so that the interference of the heat dissipated by the second decoder 40 to the operation of the controller 30 and the interference of the heat dissipated by the controller 30 to the operation of the second decoder 40 can be avoided, and thus, the service lives of the controller 30 and the second decoder 40 can be prolonged.

In some embodiments of the present invention, as shown in fig. 1, the controller 30 is provided with a bus interface, the bus interface is connected to the bus 50, the second decoder 40 is provided with a decoder interface, and the decoder interface is connected to the connection line 60. The other end of the bus 50 and the other end of the connection line 60 are also connected to the first decoder 20, so that a communication channel can be established between the controller 30 and the first decoder 20 and between the second decoder 40 and the first decoder 20. So that the digital signals output from the first decoder 20 are transferred to the controller 30 and the second decoder 40 through the bus 50 and the connection line 60, respectively.

In detail, the position sensor 10 may be a resolver. The rotation angle of the motor shaft is measured by the position sensor 10 by adopting a rotary transformer, so that the measurement is more convenient and accurate. There are various processing chips of the resolver, for example, chips of AD2S1205, AD2S1210, PGA411, and the like.

Further, the second decoder 40 may be an incremental decoder. The incremental encoder converts displacement into periodic electrical signals, and then converts the electrical signals into counting pulses, and the number of the pulses is used for expressing the magnitude of the displacement. As shown in fig. 2, the incremental decoder has a/B/NM three-phase signal output, where A, B two phases differ by 90 °, and when the electrical angle is zero, the pulse signal NM is generated. The incremental decoder generates corresponding values as the a/B/NM signal changes, which are used as the current electrical angle. The incremental decoder has small volume, high precision, simple structure, strong anti-interference capability, reasonable price and high reliability.

The controller 30 may be any one of a single chip microcomputer, a single board computer, a microcomputer, and a PLC (programmable logic controller). For example, the controller 30 may be a single chip microcomputer, which has a small size, high flexibility, a low price, and a convenient use, can process a large amount of data, and has a high data processing efficiency.

Bus 50 may be an SPI bus, an SCI bus, an IIC bus, or a UART bus. The SPI bus is a high-speed and synchronous communication bus, only four wires are occupied on pins of a chip, the pins of the chip are saved, and meanwhile, space is saved for layout of a circuit board, and convenience is provided. The SCI bus is a universal asynchronous communication interface UART, and is substantially identical to the asynchronous communication function of MCS-51. The IIC bus generally has two signal lines, one is a bidirectional data line SDA, the other is a clock line SCL, all serial data SDAs connected to the IIC bus device are connected to the SDA of the bus, and the clock line SCL of each device is connected to the SCL of the bus. The UART is a general serial data bus for asynchronous communication, and the bus performs bidirectional communication, enabling transmission and reception. The specific interface type depends on the bus interface type of the first decoder 20, for example, in the position detection system 100 of the motor of the embodiment of the present invention, the first decoder 20 provides an SPI bus interface, so the SPI bus can be adopted as the bus 50.

In some embodiments of the present invention, as shown in fig. 1, the connection line 60 is composed of three data transmission lines, and is electrically connected to the first decoder 20. Specifically, because the incremental decoder is provided with A/B/NM three-phase signal output, and the signal output of each phase is different, three data transmission lines are arranged to be respectively and electrically connected with the A/B/NM three-phase signal output end, so that the three-phase signal output is not influenced mutually.

As shown in fig. 3, the work flow of the position detecting system 100 of the motor according to the embodiment of the present invention can be performed according to the following steps: firstly, in the system startup initialization phase, the electrical angle of the resolver decoder chip is directly read through the SPI bus, and this electrical angle is 12bit of data, depending on the specific decoding chip. Then, the electrical angle data is used as the initial value of the incremental decoder module. Then, starting the incremental decoder; after start-up, the incremental decoder generates corresponding values as the a/B/NM signal changes, and these values are used as the current electrical angle. Finally, during normal operation of the program, the controller 30 reads the electrical angle produced by the incremental decoder directly. Complicated timing sequences such as the SPI bus are avoided from being called, and therefore a large amount of control time of the controller 30 is saved.

It should be noted that, in general, the resolver decoder chip is provided with status feedback signals, which will indicate whether the resolver decoder chip is faulty or not. If yes, executing a fault processing flow. The fault processing flow is processed by following steps: first, the controller 30 attempts to clear the resolver decoder chip of a malfunction. If the fault is cleared, execution proceeds as in the flow of FIG. 3. Thus, the detection system 100 can be made more powerful by intelligently troubleshooting and clearing the fault.

In the position detecting system 100 of the motor of the embodiment of the present invention, the controller 30 can adopt a TMS320F280049 microcontroller chip in the prior art, and this chip can have an SPI module, and moreover, an incremental decoder eQEP is integrated as the second decoder 40, and the first decoder 20 on the periphery adopts an AD2S 1210. The position detection system 100 of the motor can read the electric angle information more accurately and quickly.

According to the embodiment of the present invention, the position sensor 10 is disposed on the motor, including the motor and the position detecting system 100 of the motor of the above embodiment. The position detection system 100 of the motor is installed on the vehicle, and can quickly and accurately read the rotating electrical angle of the motor shaft of the vehicle so as to be used by other control systems on the vehicle, thereby better controlling the running state of the vehicle.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

In the description of the present invention, "the first feature" and "the second feature" may include one or more of the features. In the description of the present invention, "a plurality" means two or more. In the description of the present invention, the first feature "on" or "under" the second feature may include the first and second features being in direct contact, and may also include the first and second features being in contact with each other not directly but through another feature therebetween. In the description of the invention, the first feature being "on", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A position detection system for an electric machine, comprising:

a position sensor;

a first decoder electrically connected to the position sensor;

a controller electrically connected to the first decoder through a bus;

the second decoder is electrically connected with the controller, and the second decoder is electrically connected with the first decoder through a connecting wire so as to transmit the electrical angle signal transmitted by the first decoder to the controller.

2. The position detection system of an electric machine according to claim 1, wherein the second decoder is integrated on the controller.

3. The position detecting system of an electric motor according to claim 1, wherein the controller is electrically connected to the second decoder through a connection line.

4. The position detecting system of an electric motor according to claim 1, wherein the controller is provided with a bus interface, the bus interface is connected to the bus, and the second decoder is provided with a decoder interface, the decoder interface is connected to the connecting line.

5. The position detection system of an electric machine according to claim 1, wherein the position sensor is a resolver.

6. The position detection system of an electric motor according to claim 1, wherein the second decoder is an incremental decoder.

7. The position detecting system of an electric motor according to claim 1, wherein the controller is any one of a single chip microcomputer, a single board computer, a microcomputer, and a PLC.

8. The position sensing system of an electric motor according to claim 1, wherein the bus is an SPI bus, an SCI bus, an IIC bus, or a UART bus.

9. The position sensing system of an electric motor according to claim 1, wherein the connection line is composed of three data transmission lines and each is electrically connected to the first decoder.

10. A vehicle, characterized by comprising:

a motor;

a position detection system for an electric motor as claimed in any one of claims 1 to 9, said position sensor being provided on said electric motor.