A motor rotor angle synchronous acquisition device for an isolated encoder and controller communication

Abstract

A motor rotor angle synchronous acquisition device for isolated encoder and controller communication, comprising a motor main controller, a TRIG synchronous trigger module, an isoSPI host communication module, an isoSPI isolated communication link, an isoSPI slave communication module, an encoder interface module and a motor encoder; the encoder interface module comprises an encoder interface unit, a latch control unit, an angle latch unit, a data buffer unit and a frame buffer unit, the trigger input end of the latch control unit is connected with the TRIG synchronous trigger module, the data input end of the angle latch unit is connected with the encoder interface unit, the data buffer unit and the frame buffer unit are connected with the isoSPI slave communication module, through the hardware trigger, latch, buffer and isolated communication structure, the rotor angle data output by the motor encoder is latched according to the synchronous trigger signal at the motor end, and is read by the motor main controller through the isoSPI isolated communication link.

Description

Technical Field

[0001] This utility model belongs to the field of signal acquisition technology, specifically relating to a synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller; it is particularly suitable for application scenarios in high-voltage, high-power servo motor control systems, where the motor main controller reads the encoder angle data at the motor end through isolated communication, and requires a fixed correspondence between the encoder angle latching hardware timing and the PWM control cycle, current sampling timing, or current loop execution timing. Background Technology

[0002] Permanent magnet synchronous motors, servo motors, and torque motor control systems typically employ closed-loop control. The motor controller needs to acquire rotor angle data, and the encoder, as the rotor angle detection element, has its output data accuracy, real-time performance, and stability that affect the performance of the motor control system.

[0003] In high-voltage, high-power motor controllers, power devices such as IGBTs, MOSFETs, and SiC generate strong common-mode interference, differential-mode interference, and electromagnetic radiation during high-speed switching. Encoders are typically mounted at the motor end, while the main motor controller is usually located on the controller motherboard, with a certain distance between them. Encoder communication cables are susceptible to noise from power cables, drive modules, inverter bridge switches, and ground potential differences, leading to encoder communication errors, data delays, data jumps, or short-term communication anomalies.

[0004] In existing technologies, differential communication, digital isolation, optocoupler isolation, RS485, BiSS-C, EnDat, and SPI isolation communication are commonly used to improve the reliability of encoder communication and achieve data transmission between the motor controller and the encoder. These solutions can improve the anti-interference capability of encoder data transmission to a certain extent, but they still have shortcomings.

[0005] First, existing encoder communication structures typically focus on whether encoder data can be read by the main controller, but lack a trigger path that defines the timing of encoder angle data latching from a hardware perspective. The moment the main controller receives the angle data is often not the same as the moment the encoder actually samples or latches the angle.

[0006] Secondly, in existing encoder interface structures, there is usually no fixed hardware correspondence between the encoder angle data acquisition time and the motor PWM control cycle, current sampling time, or current loop execution timing. For high-speed motors, even if the communication data itself is error-free, an uncertain angle acquisition time may still cause angle phase deviation.

[0007] Third, in systems where the main controller and encoder interface board are arranged separately, the encoder's original signal is easily subject to electromagnetic interference if it is transmitted over a long distance to the main controller; if the encoder data is read only through ordinary communication, it is difficult to make the read data correspond to a specific hardware latching time.

[0008] Fourth, existing isolated communication structures generally only solve the problems of electrical isolation and data transmission, and do not integrate synchronous triggering, angle latching, data buffering, frame status identification and isolated reading into a complete synchronous acquisition device.

[0009] Therefore, it is necessary to propose a synchronous acquisition device for motor rotor angle that enables communication between the isolated encoder and the controller, in order to overcome the problems mentioned above. Utility Model Content

[0010] Therefore, the purpose of this utility model is to provide a synchronous acquisition device for motor rotor angle for communication between isolated encoder and controller, so as to solve the problems of lack of fixed hardware correspondence between encoder angle acquisition time and motor PWM control cycle, easy interference during long-distance transmission of encoder raw angle signal, and lack of angle latching and data buffering hardware structure at encoder interface.

[0011] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0012] A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller includes:

[0013] The motor master controller is used to generate PWM control signals to drive the motor, and to generate synchronous trigger signals and SPI communication signals.

[0014] The TRIG synchronous trigger module is connected to the motor main controller and is used to receive and send the synchronous trigger signal output by the motor main controller.

[0015] The isoSPI master communication module is connected to the motor master controller and is used to receive the SPI communication signal output by the motor master controller, convert the SPI communication signal into an isoSPI differential signal for isolated transmission, and transmit it outward.

[0016] The isoSPI isolated communication link is connected to the isoSPI master communication module and is used to receive and transmit isoSPI differential signals.

[0017] The isoSPI slave communication module is connected to the isoSPI isolated communication link. It is used to receive the isoSPI differential signal transmitted from the isoSPI isolated communication link, restore the isoSPI differential signal to the SPI communication signal, and transmit it outward.

[0018] The encoder interface module is connected to the TRIG synchronous trigger module, the isoSPI slave communication module and the motor encoder respectively. It is used to receive the synchronous trigger signal output by the TRIG synchronous trigger module and the rotor angle signal output by the motor encoder, latch the rotor angle signal according to the synchronous trigger signal, buffer the latched rotor angle data, frame it and output it to the isoSPI slave communication module.

[0019] The motor encoder, connected to the encoder interface module, is used to detect the motor rotor angle and output the rotor angle signal.

[0020] In a preferred configuration, the motor main controller includes:

[0021] The PWM control output terminal is used to connect to an external power drive module and output a PWM control signal.

[0022] The synchronous trigger signal output terminal is connected to the input terminal of the TRIG synchronous trigger module and is used to output the synchronous trigger signal;

[0023] The SPI communication interface connects to the data input terminal of the isoSPI master communication module and is used to output SPI communication signals.

[0024] In a preferred embodiment, the encoder interface module includes:

[0025] The encoder interface unit is connected to the motor encoder and is used to receive the rotor angle signal output by the motor encoder and transmit the rotor angle signal to the encoder interface module.

[0026] The latch control unit is connected to the TRIG synchronization trigger module and is used to receive the synchronization trigger signal output by the TRIG synchronization trigger module and generate a latch enable signal based on the synchronization trigger signal.

[0027] An angle latching unit is connected to the encoder interface unit and the latching control unit respectively. It is used to receive the rotor angle signal output by the encoder interface unit and the latching enable signal output by the latching control unit, and latch the rotor angle signal into latched angle data under the control of the latching enable signal.

[0028] The data buffer unit, connected to the angle latch unit, is used to receive and buffer the latched angle data output by the angle latch unit;

[0029] The frame buffer unit is connected to the data buffer unit and the isoSPI slave communication module respectively. It is used to receive the latched angle data output by the data buffer unit, assemble the latched angle data into a data frame, and output the data frame to the isoSPI slave communication module.

[0030] In a preferred configuration, the frame buffer unit includes at least two of the following: a frame header field storage area, a frame sequence number field storage area, a latch period sequence number field storage area, an angle data field storage area, an encoder status field storage area, a latch completion flag field storage area, and a check field storage area.

[0031] In a preferred embodiment, the encoder interface unit includes an encoder interface terminal for connecting to an absolute encoder, magnetic encoder, photoelectric encoder, BiSS-C encoder, EnDat encoder, or SPI encoder. The signal terminal of the encoder interface terminal is connected to the corresponding signal terminal of the motor encoder to receive the rotor angle signal output by the motor encoder. The latch control unit is any one of an edge-triggered D flip-flop, JK flip-flop, Schmitt trigger, and an internal edge detection logic circuit of a programmable logic device. The angle latch unit is any one or more of a register, latch, dual-port RAM, FIFO buffer, internal register of a programmable logic device, and internal register of a local controller. The data buffer unit is any one or more of a register, latch, dual-port RAM, FIFO buffer, internal register of a programmable logic device, and internal register of a local controller.

[0032] In a preferred configuration, the TRIG synchronous trigger module includes at least one of a PWM comparison trigger unit, a timer trigger unit, a GPIO trigger unit, and a programmable logic trigger unit; a signal conditioning circuit is further provided between the TRIG synchronous trigger module and the encoder interface module; the signal conditioning circuit includes at least one of a digital isolator, a differential driver, a differential receiver, a Schmitt trigger, a current-limiting resistor, a filter capacitor, and an electrostatic protection device.

[0033] In a preferred configuration, the isoSPI isolated communication link is a twisted pair cable, a shielded twisted pair cable, a differential communication cable, or an isolated communication cable with a shielding layer; the first end of the isoSPI isolated communication link is connected to the differential signal output end of the isoSPI master communication module, and the second end of the isoSPI isolated communication link is connected to the differential signal input end of the isoSPI slave communication module, for bidirectional transmission of isoSPI differential signals between the isoSPI master communication module and the isoSPI slave communication module.

[0034] In a preferred configuration, the motor main controller and the isoSPI master communication module are mounted on the motor controller motherboard; the isoSPI slave communication module and the encoder interface module are mounted on the motor encoder interface board; the motor encoder interface board is positioned close to the motor encoder; the motor controller motherboard and the motor encoder interface board are connected via an isoSPI isolated communication link; the rotor angle signal output by the motor encoder is latched and buffered on the motor encoder interface board by the encoder interface module, and then transmitted to the isoSPI master communication module on the motor controller motherboard via the isoSPI isolated communication link.

[0035] In a preferred embodiment, the encoder interface module further includes an encoder communication protocol parsing unit, a data verification unit, and an isolated power supply module. The encoder communication protocol parsing unit is connected between the encoder interface unit and the angle latching unit, and is used to parse the rotor angle signal according to the protocol and transmit the parsed rotor angle data to the angle latching unit. The data verification unit is connected between the angle latching unit and the data buffer unit, and is used to verify the latched angle data and transmit the verified latched angle data to the data buffer unit. The isolated power supply module is used to draw power from an external DC power supply and provide isolated DC operating power to the isoSPI slave communication module, the encoder interface module, the angle latching unit, the data buffer unit, and the frame buffer unit, respectively.

[0036] In a preferred configuration, the output of the TRIG synchronous trigger module is connected to the synchronous trigger input of the encoder interface module via an independent physical signal line; the independent physical signal line is a single-ended signal line or a differential signal line; the synchronous trigger signal is transmitted from the TRIG synchronous trigger module to the encoder interface module via the independent physical signal line.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] First, a hardware triggering latching path is formed by the TRIG synchronous triggering module, latching control unit and angle latching unit, so that the rotor angle data output by the motor encoder can be stored at the motor encoder interface under the action of a certain trigger signal.

[0039] Secondly, by setting up a data buffer unit and a frame buffer unit in the encoder interface module, the latched rotor angle data has a local hardware buffer carrier, reducing the impact of changes in the communication reading time of the motor main controller on the angle acquisition time.

[0040] Third, by using the isoSPI master communication module, isoSPI isolated communication link, and isoSPI slave communication module, isolated communication between the motor controller motherboard and the motor encoder interface board is achieved, thereby improving the reliability of motor encoder angle data transmission under high voltage, high power, and strong electromagnetic interference environments.

[0041] Fourth, by placing the encoder interface module on the encoder interface board at the motor end, close to the motor encoder, the original angle signal of the motor encoder can be received, latched, and buffered at the motor end, reducing the risk of interference during long-distance transmission of the original angle signal. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a block diagram of the overall structure of the motor rotor angle synchronous acquisition device of this utility model;

[0044] Figure 2 This is a schematic diagram of the physical layout and isolated communication link structure of the motor controller motherboard and the motor-end encoder interface board of this utility model.

[0045] Figure 3 for Figure 2 A schematic diagram of the internal data link of the encoder interface module;

[0046] Figure 4 for Figure 2 A schematic diagram of latching control and isolated power supply for the encoder interface module.

[0047] In the diagram: 1. Motor main controller; 2. TRIG synchronous trigger module; 3. isoSPI master communication module; 4. isoSPI slave communication module; 5. Encoder interface module; 6. Motor encoder; 7. Motor; 10. Motor controller motherboard; 20. Motor-side encoder interface board; 30. isoSPI isolated communication link; 51. Encoder interface unit; 52. Latch control unit; 53. Angle latch unit; 54. Data buffer unit; 55. Frame buffer unit; 56. Encoder communication protocol parsing unit; 57. Data verification unit; 58. Isolated power supply module. Detailed Implementation

[0048] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0049] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In addition, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0050] like Figure 1 As shown, the present invention provides a motor rotor angle synchronous acquisition device for communication between an isolated encoder and a controller, comprising: a motor main controller 1, a TRIG synchronous trigger module 2, an isoSPI master communication module 3, an isoSPI isolated communication link 30, an isoSPI slave communication module 4, an encoder interface module 5, and a motor encoder 6.

[0051] The motor main controller 1 is located on the motor controller side and is used to generate PWM control signals to drive the motor 7, as well as to generate synchronous trigger signals and SPI communication signals. The motor main controller 1 includes a PWM control output terminal, a synchronous trigger signal output terminal, and an SPI communication interface. The PWM control output terminal is used to connect to an external power drive module, outputting PWM control signals to control the on / off state of power switching devices; the synchronous trigger signal output terminal is connected to the input terminal of the TRIG synchronous trigger module 2, used to output synchronous trigger signals; the SPI communication interface is connected to the data input terminal of the isoSPI master communication module 3, used to output SPI communication signals to achieve data interaction with the encoder interface module 5.

[0052] The TRIG synchronous trigger module 2 is connected to the motor main controller 1 and is used to receive the synchronous trigger signal output by the motor main controller 1 and transmit the synchronous trigger signal outward. The TRIG synchronous trigger module 2 may include at least one of a PWM comparison trigger unit, a timer trigger unit, a GPIO trigger unit, or a programmable logic trigger unit. Specifically, the PWM comparison trigger unit receives the PWM comparison value signal output by the motor main controller 1 and outputs a synchronous trigger signal when the PWM count value matches the PWM comparison value; the timer trigger unit receives the timer count value signal output by the motor main controller 1 and outputs a synchronous trigger signal when the timer count value reaches a preset value; the GPIO trigger unit receives the GPIO level signal output by the motor main controller 1 and outputs a synchronous trigger signal according to the transition of the GPIO level signal; the programmable logic trigger unit receives the logic control signal output by the motor main controller 1 and outputs a synchronous trigger signal according to the logic control signal.

[0053] A signal conditioning circuit can also be provided between the TRIG synchronous trigger module 2 and the encoder interface module 5. This signal conditioning circuit is connected between the output terminal of the TRIG synchronous trigger module 2 and the synchronous trigger input terminal of the encoder interface module 5. It is used to isolate, differentially drive, shape the waveform, limit current, filter, or perform electrostatic discharge (ESD) protection on the synchronous trigger signal to enhance the transmission reliability of the synchronous trigger signal in environments with strong electromagnetic interference. The signal conditioning circuit may include at least one of the following: a digital isolator, a differential driver, a differential receiver, a Schmitt trigger, a current-limiting resistor, a filter capacitor, and an ESD protection device.

[0054] The isoSPI master communication module 3 is connected to the motor master controller 1 and is used to receive the SPI communication signal output by the motor master controller 1, convert the SPI communication signal into an isoSPI differential signal suitable for isolated transmission, and transmit the isoSPI differential signal outward. The isoSPI master communication module 3 includes an SPI interface circuit, an isoSPI master communication transceiver chip, a master coupling transformer, a master termination resistor, a master common-mode inductor, and a master transient voltage suppression device. The first end of the SPI interface circuit is connected to the SPI communication interface of the motor master controller 1 to receive the SPI communication signal output by the motor master controller 1. The second end of the SPI interface circuit is connected to the SPI signal end of the isoSPI master communication transceiver chip to transmit the SPI communication signal to the isoSPI master communication transceiver chip. The differential signal end of the isoSPI master communication transceiver chip is connected to the first end of the isoSPI isolated communication link 30 via the master coupling transformer to convert the SPI communication signal into an isoSPI differential signal and transmit it to the isoSPI isolated communication link 30 via the master coupling transformer. The master termination resistor is connected between the differential signal end of the isoSPI master communication transceiver chip and the master coupling transformer to perform impedance matching on the isoSPI differential signal to reduce signal reflection. The master common-mode inductor is connected in series between the master coupling transformer and the isoSPI isolated communication link 30 to suppress common-mode interference on the isoSPI differential signal. The master transient voltage suppression device is connected in parallel between the differential signal lines of the isoSPI isolated communication link 30 to suppress transient overvoltage on the isoSPI differential signal and protect the subsequent circuits from surge and electrostatic discharge damage.

[0055] The isoSPI isolated communication link 30 is connected to the isoSPI master communication module 3 and is used to receive and transmit isoSPI differential signals. The isoSPI isolated communication link 30 is a twisted pair cable, shielded twisted pair cable, differential communication cable, or an isolated communication cable with a shielding layer. Its first end is connected to the differential signal output terminal of the isoSPI master communication module 3, and its second end is connected to the differential signal input terminal of the isoSPI slave communication module 4, used for bidirectional transmission of isoSPI differential signals between the isoSPI master communication module 3 and the isoSPI slave communication module 4. The isoSPI isolated communication link 30 adopts differential transmission, has strong common-mode interference suppression capability and electromagnetic interference resistance, and is suitable for long-distance signal transmission between the controller motherboard and the encoder interface board of the motor 7 in high-voltage, high-power motor 7 control systems.

[0056] The isoSPI slave communication module 4 is connected to the isoSPI isolated communication link 30. It receives the isoSPI differential signal transmitted from the isoSPI isolated communication link 30, restores the isoSPI differential signal to an SPI communication signal, and transmits it externally. The isoSPI slave communication module 4 includes an isoSPI slave communication transceiver chip, a slave coupling transformer, a slave termination resistor, a slave common-mode inductor, a slave transient voltage suppression device, and a local interface circuit. The differential signal terminal of the isoSPI slave communication transceiver chip is connected to the second terminal of the isoSPI isolated communication link 30 via the slave coupling transformer. It receives the isoSPI differential signal transmitted from the isoSPI isolated communication link 30 and restores the isoSPI differential signal to an SPI communication signal. The slave coupling transformer is connected between the isoSPI slave communication transceiver chip and the isoSPI isolated communication link 30 to perform transformer coupling transmission of the isoSPI differential signal while achieving electrical isolation. The slave termination resistor is connected between the differential signal terminal of the isoSPI slave communication transceiver chip and the slave coupling transformer to perform transformer coupling transmission of the isoSPI differential signal and achieve electrical isolation. The signal undergoes impedance matching; a common-mode inductor is connected in series between the slave-end coupling transformer and the isoSPI isolated communication link 30 to suppress common-mode interference on the isoSPI differential signal; a slave-end transient voltage suppression device is connected in parallel between the differential signal lines of the isoSPI isolated communication link 30 to suppress transient overvoltage on the isoSPI differential signal; a local interface circuit is connected between the isoSPI slave-end communication transceiver chip and the encoder interface module 5 to transmit the SPI communication signal restored by the isoSPI slave-end communication transceiver chip to the encoder interface module 5, and to transmit the data frame signal output by the encoder interface module 5 to the isoSPI slave-end communication transceiver chip.

[0057] It should be noted that both the isoSPI master and slave communication transceivers use the LTC6820HMS communication transceiver chip, the MCU of motor master controller 1 is a PIC32MK0512MCF064, and the MCU of motor encoder 6 is an STM32H745XIH6.

[0058] Encoder interface module 5 is connected to TRIG synchronous trigger module 2, isoSPI slave communication module 4, and motor encoder 6 respectively. It receives the synchronous trigger signal output from TRIG synchronous trigger module 2 and the rotor angle signal output from motor encoder 6. Based on the synchronous trigger signal, it latches the rotor angle signal using hardware latching. The latched rotor angle data is then buffered, framed, and output to isoSPI slave communication module 4. For example... Figure 3As shown, the encoder interface module 5 includes an encoder interface unit 51, a latch control unit 52, an angle latch unit 53, a data buffer unit 54, and a frame buffer unit 55.

[0059] The encoder-side data terminal of the encoder interface unit 51 is connected to the data terminal of the motor encoder 6 to receive the rotor angle signal output by the motor encoder 6. The master control-side data terminal of the encoder interface unit 51 is connected to the data input terminal of the angle latch unit 53 to transmit the received rotor angle signal to the encoder interface module 5. The encoder interface unit 51 includes an encoder interface terminal for connecting an absolute encoder, magnetic encoder, photoelectric encoder, BiSS-C encoder, EnDat encoder, or SPI encoder. The signal terminal of the encoder interface terminal is connected to the corresponding signal terminal of the motor encoder 6 to receive the rotor angle signal output by the motor encoder 6.

[0060] The trigger input terminal of the latch control unit 52 is connected to the output terminal of the TRIG synchronous trigger module 2 to receive the synchronous trigger signal output by the TRIG synchronous trigger module 2. The latch control output terminal of the latch control unit 52 is connected to the latch enable terminal of the angle latch unit 53 to generate a latch enable signal based on the received synchronous trigger signal and output it to the angle latch unit 53. The latch control unit 52 is any one of the edge-triggered D flip-flop, JK flip-flop, Schmitt trigger, and edge detection logic circuit inside a programmable logic device. Its trigger input terminal is connected to the output terminal of the TRIG synchronous trigger module 2 to receive the synchronous trigger signal, its data input terminal is connected to a fixed high level or a fixed low level, and its output terminal is connected to the latch enable terminal of the angle latch unit 53. The latch control unit 52 generates a latch enable signal at its output terminal based on the edge transition (rising edge or falling edge) of the synchronous trigger signal.

[0061] The data input terminal of the angle latch unit 53 is connected to the data output terminal of the encoder interface unit 51 to receive the rotor angle signal output by the encoder interface unit 51. The latch enable terminal of the angle latch unit 53 is connected to the latch control output terminal of the latch control unit 52 to receive the latch enable signal output by the latch control unit 52. The data output terminal of the angle latch unit 53 is connected to the data input terminal of the data buffer unit 54 to latch the rotor angle signal as latched angle data during the effective level of the latch enable signal and output the latched angle data to the data buffer unit 54. The angle latch unit 53 can be any one or more of a register, latch, dual-port RAM, FIFO buffer, internal register of a programmable logic device, or internal register of a local controller. The angle latch unit 53 latches the current level state of the rotor angle data on the data input terminal to its internal storage unit at the edge (rising edge or falling edge) of the latch enable signal, and keeps the latched data unchanged after the latch enable signal is invalid until it is updated when the next latch enable signal is valid, thereby realizing hardware freezing of the angle data.

[0062] The data input terminal of the data buffer unit 54 is connected to the data output terminal of the angle latch unit 53, and is used to receive the latched angle data output by the angle latch unit 53. The write enable terminal of the data buffer unit 54 is connected to the data valid flag output terminal of the angle latch unit 53, and is used to receive the data valid flag signal output by the angle latch unit 53, and write the latched angle data into the data buffer unit 54 when the data valid flag signal is valid. The read enable terminal of the data buffer unit 54 is connected to the data read request output terminal of the frame buffer unit 55, and is used to receive the data read request signal output by the frame buffer unit 55, and output the latched angle data to the frame buffer unit 55 when the data read request signal is valid. The data output terminal of the data buffer unit 54 is connected to the data input terminal of the frame buffer unit 55, and is used to output the latched angle data to the frame buffer unit 55. The data buffer unit 54 can be any one or more of the following: register, latch, dual-port RAM, FIFO buffer, internal register of programmable logic device, and internal register of local controller. The data cache unit 54 provides a hardware cache carrier for the latched angle data through its storage medium, so that the latched angle data can be temporarily stored at the encoder interface, reducing the impact of the time change of the main controller reading data through the isoSPI communication link on the determinism of the angle acquisition time.

[0063] The data input terminal of the frame buffer unit 55 is connected to the data output terminal of the data buffer unit 54, and is used to receive the latched angle data output by the data buffer unit 54; the data output terminal of the frame buffer unit 55 is connected to the data input terminal of the isoSPI slave communication module 4, and is used to assemble the latched angle data into a data frame and output the data frame to the isoSPI slave communication module 4. The frame buffer unit 55 includes at least two of the following: a frame header field storage area, a frame sequence number field storage area, a latch period sequence number field storage area, an angle data field storage area, an encoder status field storage area, a latch completion flag field storage area, and a verification field storage area. The frame header field storage area stores frame start identifier data to identify the start position of the data frame; the frame sequence number field storage area stores the sequence number data of the current data frame to identify the transmission order of the data frames; the latch period sequence number field storage area stores the sequence number data of the latch period corresponding to the latch angle data to identify the PWM control period corresponding to the frame data; the angle data field storage area stores the latch angle data, i.e., the rotor angle value output by the motor encoder 6 at the moment of synchronous triggering; the encoder status field storage area stores the status data of the motor encoder 6, such as encoder communication status, error flags, etc.; the latch completion flag field storage area stores latch completion flag data to indicate whether the frame data has been effectively latched; and the check field storage area stores check code data for the receiving end to perform data integrity verification. Each field storage area is a storage area with an independent physical storage address in the frame buffer unit 55. A data bus is provided between the data output terminal of the frame buffer unit 55 and the data input terminal of the isoSPI slave communication module 4. This data bus can be an SPI bus, a parallel bus, or a serial bus. The data frame assembled in the frame buffer unit 55 is transmitted to the isoSPI slave communication module 4 through this data bus.

[0064] The motor encoder 6 is connected to the encoder interface module 5 and is used to detect the motor rotor angle and output the rotor angle signal. The motor encoder 6 can be any one of an absolute encoder, magnetic encoder, photoelectric encoder, BiSS-C encoder, EnDat encoder or SPI encoder. Its data terminal is connected to the encoder side data terminal of the encoder interface unit 51 and is used to transmit the detected rotor angle signal to the encoder interface unit 51 in a digital communication manner.

[0065] In a preferred structure, such as Figure 2As shown, the motor main controller 1 and the isoSPI master communication module 3 are mounted on the motor controller motherboard 10, while the isoSPI slave communication module 4 and the encoder interface module 5 are mounted on the motor-end encoder interface board 20. The motor-end encoder interface board 20 is positioned close to the motor encoder 6. The motor controller motherboard 10 and the motor-end encoder interface board 20 are connected via an isoSPI isolated communication link 30. The rotor angle signal output by the motor encoder 6 is latched and buffered on the motor-end encoder interface board 20 by the encoder interface module 5, and then transmitted to the isoSPI master communication module 3 on the motor controller motherboard 10 via the isoSPI isolated communication link 30. With this arrangement, the original angle signal output by the motor encoder 6 can be received, latched, and buffered locally on the motor-end encoder interface board 20 before being transmitted to the motor controller motherboard 10 via the isoSPI isolated communication link 30, thereby reducing the risk of interference during long-distance transmission of the encoder's original angle signal.

[0066] In a preferred configuration, a first connector is provided on the motor controller motherboard 10, and a second connector is provided on the motor-end encoder interface board 20. The first connector is located on the edge region of the motor controller motherboard 10 and is used to connect to the first end of the isoSPI isolated communication link 30; the second connector is located on the edge region of the motor-end encoder interface board 20 and is used to connect to the second end of the isoSPI isolated communication link 30. The isoSPI isolated communication link 30 is pluggably connected between the motor controller motherboard 10 and the motor-end encoder interface board 20 through the first and second connectors, facilitating system assembly, maintenance, and upgrades.

[0067] In a preferred configuration, the motor-side encoder interface board 20 is further provided with an encoder connector. The encoder connector is located on the edge area of ​​the motor-side encoder interface board 20 near the motor encoder 6. The first end of the encoder connector is connected to the signal line of the motor encoder 6, and the second end of the encoder connector is connected to the data end of the encoder interface unit 51. The rotor angle signal output by the motor encoder 6 is transmitted to the encoder interface unit 51 through the encoder connector.

[0068] In a preferred structure, such as Figure 4As shown, the encoder interface module 5 also includes an encoder communication protocol parsing unit 56. The encoder communication protocol parsing unit 56 is connected between the encoder interface unit 51 and the angle latching unit 53. Its input terminal is connected to the data output terminal of the encoder interface unit 51, and it is used to receive the rotor angle signal output by the encoder interface unit 51, and to perform protocol parsing on the rotor angle signal, extracting angle data from the data frame of the encoder communication protocol (such as BiSS-C protocol, EnDat protocol, or SPI protocol). The output terminal of the encoder communication protocol parsing unit 56 is connected to the data input terminal of the angle latching unit 53, and it is used to transmit the protocol-parsed rotor angle data to the angle latching unit 53.

[0069] In a preferred structure, such as Figure 4 As shown, the encoder interface module 5 also includes a data verification unit 57. The data verification unit 57 is connected between the angle latch unit 53 and the data buffer unit 54. Its input is connected to the data output of the angle latch unit 53, and it receives the latched angle data output by the angle latch unit 53, performing parity or CRC checks on the latched angle data. The output of the data verification unit 57 is connected to the data input of the data buffer unit 54, and it transmits the verified latched angle data to the data buffer unit 54. The verification result can be stored in the encoder status field storage area or the verification field storage area of ​​the frame buffer unit 55.

[0070] In a preferred structure, such as Figure 4 As shown, the encoder interface module 5 also includes an isolated power supply module 58. The isolated power supply module 58 includes an isolated DC / DC power supply, a voltage regulator circuit, and a power filter circuit. The input terminal of the isolated DC / DC power supply is connected to an external DC power supply to receive the DC voltage input from the external DC power supply. The output terminal of the isolated DC / DC power supply is connected to the input terminal of the voltage regulator circuit to convert the external DC voltage into an isolated DC voltage and output it to the voltage regulator circuit. The output terminal of the voltage regulator circuit is connected to the input terminal of the power filter circuit to regulate the isolated DC voltage and output it to the power filter circuit. The output terminal of the power filter circuit is connected to the power terminals of the isoSPI slave communication module 4, the encoder interface module 5, the angle latch unit 53, the data buffer unit 54, and the frame buffer unit 55, respectively, to filter the regulated DC voltage and supply the filtered DC voltage to the isoSPI slave communication module 4, the encoder interface module 5, the angle latch unit 53, the data buffer unit 54, and the frame buffer unit 55, respectively. The isolated power supply module 58 achieves electrical isolation between the power supply on the motor controller motherboard 10 and the power supply on the encoder interface board 20 at the motor end by isolating the DC / DC power supply, thus preventing ground potential difference and common-mode interference from affecting the normal operation of the encoder interface module 5 through the power supply path.

[0071] In a preferred configuration, the output of the TRIG synchronization trigger module 2 and the synchronization trigger input of the encoder interface module 5 are connected via an independent physical signal line. This independent physical signal line can be a single-ended signal line or a differential signal line. The synchronization trigger signal is transmitted from the TRIG synchronization trigger module 2 to the encoder interface module 5 through this independent physical signal line. This transmission path is physically independent of the isoSPI isolated communication link 30. This configuration ensures that the transmission of the synchronization trigger signal does not depend on the isoSPI communication link 30, thereby avoiding delays and uncertainties that may be introduced by communication link occupancy, bus arbitration, or protocol stack processing. This guarantees that the path from the generation of the synchronization trigger signal to its action on the angle latch unit 53 is completely hardware-based, deterministic, and has extremely low latency.

[0072] In a preferred configuration, the TRIG synchronous trigger module 2 further includes an isolation output unit. This isolation output unit is connected between the output of the PWM comparison trigger unit, the timer trigger unit, the GPIO trigger unit, or the programmable logic trigger unit and the output of the TRIG synchronous trigger module 2. The isolation output unit is any one of an optocoupler isolator, a magnetic coupler isolator, and a capacitor isolator. It is used to perform electrical isolation processing on the synchronous trigger signal and transmit the isolated synchronous trigger signal to the output of the TRIG synchronous trigger module 2.

[0073] The working process of this utility model is as follows: At a predetermined time within the PWM control cycle (such as the moment when the PWM count value matches the comparison value), the motor main controller 1 outputs a synchronous trigger signal through the synchronous trigger signal output terminal. This synchronous trigger signal is transmitted to the latch control unit 52 of the encoder interface module 5 via the TRIG synchronous trigger module 2 and an independent physical signal line. After detecting the edge transition of the synchronous trigger signal, the latch control unit 52 generates a latch enable signal at its output terminal and outputs it to the latch enable terminal of the angle latch unit 53. When the latch enable signal is valid, the angle latch unit 53 latches the rotor angle signal currently transmitted from the encoder interface unit 51 into latch angle data and holds this data until the next latch enable signal is valid. The latch angle data is then temporarily stored in the data buffer unit 54, and then read by the frame buffer unit 55 and assembled into a data frame containing a frame header, frame sequence number, latch cycle sequence number, angle data, encoder status, latch completion flag, and checksum. The motor main controller 1 reads the data frame from the frame buffer unit 55 of the encoder interface module 5 through the SPI communication interface via the isoSPI master communication module 3, the isoSPI isolated communication link 30 and the isoSPI slave communication module 4, and obtains the rotor angle data corresponding to the predetermined time within the PWM control cycle.

[0074] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller, characterized in that, include: The motor master controller is used to generate PWM control signals to drive the motor, and to generate synchronous trigger signals and SPI communication signals. The TRIG synchronous trigger module is connected to the motor main controller and is used to receive and send the synchronous trigger signal output by the motor main controller. The isoSPI master communication module is connected to the motor master controller and is used to receive the SPI communication signal output by the motor master controller, convert the SPI communication signal into an isoSPI differential signal for isolated transmission, and transmit it outward. The isoSPI isolated communication link is connected to the isoSPI master communication module and is used to receive and transmit isoSPI differential signals. The isoSPI slave communication module is connected to the isoSPI isolated communication link. It is used to receive the isoSPI differential signal transmitted from the isoSPI isolated communication link, restore the isoSPI differential signal to the SPI communication signal, and transmit it outward. The encoder interface module is connected to the TRIG synchronous trigger module, the isoSPI slave communication module and the motor encoder respectively. It is used to receive the synchronous trigger signal output by the TRIG synchronous trigger module and the rotor angle signal output by the motor encoder, latch the rotor angle signal according to the synchronous trigger signal, buffer the latched rotor angle data, frame it and output it to the isoSPI slave communication module. The motor encoder, connected to the encoder interface module, is used to detect the motor rotor angle and output the rotor angle signal.

2. The motor rotor angle synchronous acquisition device for communication between an isolated encoder and a controller according to claim 1, characterized in that, The motor main controller includes: The PWM control output terminal is used to connect to an external power drive module and output a PWM control signal. The synchronous trigger signal output terminal is connected to the input terminal of the TRIG synchronous trigger module and is used to output the synchronous trigger signal; The SPI communication interface connects to the data input terminal of the isoSPI master communication module and is used to output SPI communication signals.

3. The motor rotor angle synchronous acquisition device for communication between an isolated encoder and a controller according to claim 1, characterized in that, The encoder interface module includes: The encoder interface unit is connected to the motor encoder and is used to receive the rotor angle signal output by the motor encoder and transmit the rotor angle signal to the encoder interface module. The latch control unit is connected to the TRIG synchronization trigger module and is used to receive the synchronization trigger signal output by the TRIG synchronization trigger module and generate a latch enable signal based on the synchronization trigger signal. An angle latching unit is connected to the encoder interface unit and the latching control unit respectively. It is used to receive the rotor angle signal output by the encoder interface unit and the latching enable signal output by the latching control unit, and latch the rotor angle signal into latched angle data under the control of the latching enable signal. The data buffer unit, connected to the angle latch unit, is used to receive and buffer the latched angle data output by the angle latch unit; The frame buffer unit is connected to the data buffer unit and the isoSPI slave communication module respectively. It is used to receive the latched angle data output by the data buffer unit, assemble the latched angle data into a data frame, and output the data frame to the isoSPI slave communication module.

4. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 3, characterized in that, The frame buffer unit includes at least two of the following: a frame header field storage area, a frame sequence number field storage area, a latch period sequence number field storage area, an angle data field storage area, an encoder status field storage area, a latch completion flag field storage area, and a verification field storage area.

5. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 3, characterized in that, The encoder interface unit includes encoder interface terminals for connecting to an absolute encoder, magnetic encoder, photoelectric encoder, BiSS-C encoder, EnDat encoder, or SPI encoder. The signal terminals of the encoder interface terminals are connected to the corresponding signal terminals of the motor encoder to receive the rotor angle signal output by the motor encoder. The latch control unit is any one of the following: an edge-triggered D flip-flop, a JK flip-flop, a Schmitt trigger, and an internal edge detection logic circuit of a programmable logic device. The angle latch unit is any one or more of a register, latch, dual-port RAM, FIFO buffer, internal register of a programmable logic device, and internal register of a local controller. The data buffer unit is any one or more of a register, latch, dual-port RAM, FIFO buffer, internal register of a programmable logic device, and internal register of a local controller.

6. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 1, characterized in that, The TRIG synchronous triggering module includes at least one of a PWM comparison triggering unit, a timer triggering unit, a GPIO triggering unit, and a programmable logic triggering unit; a signal conditioning circuit is also provided between the TRIG synchronous triggering module and the encoder interface module; the signal conditioning circuit includes at least one of a digital isolator, a differential driver, a differential receiver, a Schmitt trigger, a current limiting resistor, a filter capacitor, and an electrostatic protection device.

7. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 1, characterized in that, The isoSPI isolated communication link is a twisted pair cable, a shielded twisted pair cable, a differential communication cable, or an isolated communication cable with a shielding layer; the first end of the isoSPI isolated communication link is connected to the differential signal output end of the isoSPI master communication module, and the second end of the isoSPI isolated communication link is connected to the differential signal input end of the isoSPI slave communication module, for bidirectional transmission of isoSPI differential signals between the isoSPI master communication module and the isoSPI slave communication module.

8. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 1, characterized in that, The motor main controller and the isoSPI master communication module are located on the motor controller motherboard; the isoSPI slave communication module and the encoder interface module are located on the motor encoder interface board; the motor encoder interface board is located close to the motor encoder; the motor controller motherboard and the motor encoder interface board are connected via an isoSPI isolated communication link; the rotor angle signal output by the motor encoder is latched and buffered by the encoder interface module on the motor encoder interface board, and then transmitted to the isoSPI master communication module on the motor controller motherboard via the isoSPI isolated communication link.

9. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 3, characterized in that, The encoder interface module further includes an encoder communication protocol parsing unit, a data verification unit, and an isolated power supply module. The encoder communication protocol parsing unit is connected between the encoder interface unit and the angle latching unit, and is used to parse the rotor angle signal according to the protocol and transmit the parsed rotor angle data to the angle latching unit. The data verification unit is connected between the angle latching unit and the data buffer unit, and is used to verify the latched angle data and transmit the verified latched angle data to the data buffer unit. The isolated power supply module is used to draw power from an external DC power supply and provide isolated DC operating power to the isoSPI slave communication module, the encoder interface module, the angle latching unit, the data buffer unit, and the frame buffer unit, respectively.

10. A synchronous acquisition device for motor rotor angle communication between an isolated encoder and a controller according to claim 1, characterized in that, The output of the TRIG synchronous trigger module and the synchronous trigger input of the encoder interface module are connected by an independent physical signal line; the independent physical signal line is a single-ended signal line or a differential signal line; the synchronous trigger signal is transmitted from the TRIG synchronous trigger module to the encoder interface module through the independent physical signal line.

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