Controller applied to integrated magnetic suspension permanent magnet motor

Abstract

The invention provides a controller applied to an integrated magnetic suspension permanent magnet motor, and relates to the technical field of magnetic suspension. The controller comprises a main control board, an eddy current sensor processing circuit, a suspension power board, a rotary power board and an input power supply. The main control board sends out a driving signal to control the suspension power board and the rotation power board, a suspension coil and a rotation coil on the motor are further driven, magnetic suspension bearing control hardware and motor rotation controller hardware are combined, and suspension and rotation of the motor are controlled through two independent chips in the process. The suspension control circuit and the rotation control circuit do not influence each other, space and cost are saved, the precision of the magnetic suspension motor can reach the standard, and the highly-integrated magnetic suspension controller shows huge application potential and prospects in the high-end fields of biochemistry, medical treatment, semiconductor manufacturing and the like.

Description

Technical Field

[0001] The present invention relates to the field of magnetic suspension technology, and in particular to a controller applied to an integrated magnetic suspension permanent magnet motor. Background Art

[0002] At present, the magnetic levitation permanent magnet motor controller basically adopts a control method in which the magnetic levitation bearing controller and the motor rotation controller are separated, and the integration is not high. The magnetic levitation bearing control and the motor controller each require a larger space and more cost, which is not suitable for providing precise control under limited space conditions. It is the current trend to integrate the magnetic levitation bearing control and the motor rotation controller. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a controller for an integrated magnetic levitation permanent magnet motor in view of the deficiencies in the above-mentioned prior art, which combines the magnetic levitation bearing control hardware with the motor rotation controller hardware. During this process, the suspension control and rotation control circuits do not affect each other, so that the accuracy of the magnetic levitation motor meets the standards.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A controller for an integrated magnetic levitation permanent magnet motor comprises a main control board, an eddy current sensor processing circuit, a suspension power board, a rotation power board and an input power supply; the suspension power board comprises four groups of suspension coil driving hardware circuits, further comprising a suspension driving chip and a peripheral circuit, for driving the suspension coil on the motor; the rotation power board comprises a rotation coil driving hardware circuit, further comprising a rotation driving chip and a peripheral circuit, for driving the rotation coil on the motor; the suspension driving chip is controlled by a suspension CPU on the main control board sending a driving signal to drive the suspension coil to form a suspension magnetic field; the rotation driving chip is controlled by a rotation CPU on the main control board sending a driving signal to drive the rotation coil to form a rotating magnetic field; the two controls are decoupled from the hardware; the eddy current sensor processing circuit is used for processing a rotor displacement signal measured by the eddy current sensor and transmitting the signal to the main control board; the suspension coil and the rotation coil share a group of input power supplies, and the input power supply is a switching power supply integrated on a mechanical sheet metal part inside the controller.

[0006] Furthermore, the main control board includes a PWM emission chip FPGA system circuit, a suspension main control circuit, a rotation main control circuit, a communication chip system circuit, a current sensor processing circuit, and an eddy current sensor secondary processing circuit;

[0007] The PWM emitter chip FPGA system circuit includes crystal oscillator circuit, boot, download circuit, and external FLASH circuit, so that the FPGA can work normally;

[0008] The suspension main control circuit and FPGA system circuit form a suspension function; the suspension main control circuit includes a suspension CPU chip, a crystal oscillator circuit, a boot, a download circuit, and an external FLASH circuit; the ADC shares 10 channels to collect current data and rotor displacement data, 12 PWM pins to communicate with the FPGA, CAN pins to communicate with the host computer and the communication chip, and other necessary pins and circuits;

[0009] The rotation main control circuit realizes the rotation function of the motor and generates a PWM signal, including a rotation CPU chip and a crystal oscillator circuit, a boot circuit, and a download circuit;

[0010] The communication chip system circuit is used to realize the communication with the suspension CPU chip, the rotating CPU chip, the touch screen and the customer's host computer. As an information transfer station, it sends instructions to the two CPU chips; it communicates with the DSP through the CAN interface, and communicates with the rotating chip through UART; it communicates with the touch screen through the RS232 interface; and it communicates with the customer's host computer through ETHERCAT;

[0011] The current sensor processing circuit is used to collect the current signal of the current sensor and transmit it to the suspended CPU chip after processing; the current sensor signal is amplified by the circuit operational amplifier, filtered by the resistor and inductor, and finally protected by the bidirectional diode AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V;

[0012] The eddy current sensor secondary processing circuit is used to perform secondary processing on the signal of the eddy current sensor processing circuit and transmit it to the suspended CPU chip. The signal transmitted by the eddy current sensor processing circuit is amplified by an operational amplifier and filtered by a resistor and inductor. Finally, a bidirectional diode is used to protect the AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V.

[0013] Furthermore, the eddy current sensor processing circuit forms a resonant circuit through a transistor, an operational amplifier, an inductor, and a capacitor to make the eddy current sensor oscillate; subsequently, the AC signal is converted into a DC signal through a detection circuit, and then the signal is amplified by the operational amplifier and transmitted to the main control board for processing.

[0014] Furthermore, the suspension power board is used to drive the suspension coil, and the rotor is suspended by adjusting the rotor displacement signal and the current signal together; the PWM signal emitted by the FPGA is isolated by an optical coupler and converted into a +5V level, and the +5V level signal enters the suspension drive chip to drive the full-bridge circuit composed of power MOS tubes Q31, Q32, Q33, and Q34, thereby controlling the suspension coil. The current sensor measures the winding of the current sensor U3 circuit to detect the coil current. The obtained current data is transmitted to the suspension CPU chip, and the current loop closed-loop adjustment is performed internally to keep the current within a safe range of less than 4A.

[0015] Furthermore, the rotating power board is used to drive the rotating coil, detect the rotor position through the Hall sensor, and realize the rotation function of the motor, including a Hall sensor processing circuit and a rotating power output circuit; the Hall sensor processing circuit connects three Hall sensors to the Hall sensor processing circuit, and sends the switch signal to the rotating CPU chip through the optical coupler as a feedback signal for the motor rotation; the rotating power output circuit sends the PWM signal emitted by the FPGA to the rotating drive chip through the optical coupler, and the drive chip is used to drive the MOS tube.

[0016] Furthermore, the rotating power board also includes a motor stator temperature detection circuit. Two wires of an external controller PT100 for monitoring the temperature of the motor stator coil are connected to the motor stator temperature detection circuit to monitor the stator temperature and issue an alarm when the stator temperature reaches 50°C.

[0017] The beneficial effects of adopting the above technical solution are: the controller for the integrated magnetic suspension permanent magnet motor provided by the present invention combines the magnetic suspension bearing control hardware with the motor rotation controller hardware, saving space and cost, and the suspension and rotation of the motor are controlled by two independent chips without affecting each other. This highly integrated magnetic suspension controller shows great application potential and prospects in high-end fields such as biochemistry, medical treatment, and semiconductor manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A circuit diagram of the minimum system peripheral pins of the main control board FPGA provided by an embodiment of the present invention;

[0019] Figure 2 The main control board FPGA crystal oscillator, download interface, and external FLASH circuit diagram provided in the embodiment of the present invention;

[0020] Figure 3 A circuit diagram of a suspended CPU chip system provided by an embodiment of the present invention;

[0021] Figure 4 A circuit diagram of a rotating CPU chip system provided by an embodiment of the present invention;

[0022] Figure 5 The communication chip system circuit diagram provided by the embodiment of the present invention; wherein, Figure (5a) is the minimum system circuit diagram of the communication chip; Figure (5b) is the switch output circuit diagram; Figure (5c) is the CAN communication circuit diagram; Figure (5d) is the touch screen communication circuit diagram; Figure (5e) is the upper computer communication circuit diagram; Figure (5f) is the ETHERCAT interface circuit diagram;

[0023] Figure 6 A current sensor processing circuit diagram provided by an embodiment of the present invention;

[0024] Figure 7 A secondary processing circuit diagram of an eddy current sensor provided by an embodiment of the present invention;

[0025] Figure 8 A processing circuit diagram of an eddy current sensor provided by an embodiment of the present invention;

[0026] Fig. 9 A suspension power output circuit diagram of a suspension power board provided in an embodiment of the present invention;

[0027] Fig.10 A processing circuit diagram of a rotating power board Hall sensor provided in an embodiment of the present invention;

[0028] Fig.11 A rotating power output circuit diagram of a rotating power board provided in an embodiment of the present invention;

[0029] Fig.12 A circuit diagram for detecting the stator temperature of a rotating power board motor provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] A controller for an integrated magnetic levitation permanent magnet motor includes a main control board, an eddy current sensor processing circuit, a suspension power board, a rotation power board, and an input power supply. The suspension power board includes four groups of suspension coil drive hardware circuits, and further includes a suspension drive chip and a peripheral circuit. The rotation power board includes a rotation coil drive hardware circuit, and further includes a rotation drive chip and a peripheral circuit. The suspension drive chip is controlled by a suspension CPU on the main control board sending a drive signal to drive the suspension coil on the motor to form a suspension magnetic field. The rotation drive chip is controlled by a rotation CPU on the main control board sending a drive signal to drive the rotation coil on the motor to form a rotating magnetic field. The two controls are decoupled from the hardware. The eddy current sensor processing circuit is used to process the rotor displacement signal measured by the eddy current sensor and transmit it to the main control board. The suspension coil and the rotation coil share a set of input power supplies, and the input power supply is a switching power supply integrated on the mechanical sheet metal inside the controller.

[0032] The main control board includes a PWM sending chip FPGA system circuit, a suspension main control circuit, a rotation main control circuit, a communication chip system circuit, a current sensor processing circuit, and an eddy current sensor secondary processing circuit. Figure 1 and Figure 2 This is the schematic diagram of the main control board circuit, that is, the PWM sends out the chip FPGA system circuit, including the crystal oscillator circuit, boot, download circuit, external FLASH and other circuits, so that the FPGA can work normally.

[0033] The suspension main control circuit and FPGA system circuit form a suspension function. The suspension main control circuit includes a suspension CPU chip (i.e. DSP), a crystal oscillator circuit, a boot, a download circuit, an external expansion FLASH circuit, and other circuits. Figure 3 This is the minimum circuit diagram for suspending the CPU chip, i.e. the main control chip DSP28335. This part of the circuit and the FPGA system circuit form a suspension function, including crystal oscillator circuit, boot, download circuit, external FLASH and other circuits. Among them, ADC shares 10 channels to collect current data and rotor displacement data (eddy current sensor), 12 PWM pins for communicating with FPGA, CAN pins for communicating with the host computer and communication chip, and other necessary pins and circuits.

[0034] The rotation main control circuit realizes the rotation function of the motor and generates a PWM signal, including the rotation CPU chip and peripheral circuits (crystal oscillator circuit, boot, download circuit). Figure 4 This is the minimum circuit diagram of the rotating CPU chip STM32F407IGT6. The generated PWM signal and the Hall signal collected by the rotating power board are transmitted to each other through the CN8 interface.

[0035] The communication chip system circuit is used to realize communication with the suspended CPU chip, the rotating CPU chip, the touch screen and the client's host computer. As an information transfer station, it sends instructions to the two CPU chips. Figure 5 It is the system circuit diagram of the communication main control chip STM32F407VGT6. Figure (5a) is the minimum system circuit of the communication chip. The switch output is shown in Figure (5b). It communicates with the suspended CPU chip through the CAN interface (as shown in Figure (5c)), communicates with the rotating CPU chip through UART, communicates with the touch screen through the RS232 interface (as shown in Figure (5d)), and communicates with the customer host computer through ETHERCAT (as shown in Figure (5e)). ETHERCAT is shown in Figure (5f).

[0036] Figure 1-Figure 5 It is composed of various main control chip systems. In addition, there are also various sensor signal processing circuits for collecting current signals and eddy current sensor signals to DSP.

[0037] The current sensor processing circuit is used to collect the current signal of the current sensor and transmit it to the suspension CPU chip after processing. Figure 6 As shown in the figure, it is a current sensor processing circuit. The current sensor signal is amplified by the operational amplifier of the circuit in the figure above, filtered by resistors and inductors, and finally a bidirectional diode is used to protect the AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V.

[0038] The eddy current sensor secondary processing circuit is used to perform secondary processing on the signal of the eddy current sensor processing circuit and transmit it to the suspension CPU chip. Figure 7 As shown in the figure, the secondary processing circuit of the eddy current sensor is used to perform secondary processing on the signal transmitted by the eddy current sensor processing circuit. The principle is the same as that of the current sensor processing circuit. The signal is amplified by an operational amplifier, filtered by a resistor and an inductor, and finally a bidirectional diode is used to protect the AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V.

[0039] like Figure 8 As shown in the figure, it is an eddy current sensor processing circuit. The rotor displacement is measured by a customized eddy current sensor. The sensor is equivalent to an inductor. Its power interface and signal interface are connected to the circuit. Figure 8 At the Ls9 position, a resonant circuit is formed by a triode, an operational amplifier, an inductor, and a capacitor to make the eddy current sensor oscillate. The AC signal is then converted into a DC signal through a detection circuit, and then amplified by an operational amplifier and transmitted to the main control board for processing.

[0040] The suspension power board is used to drive the suspension coil, and the rotor is suspended by adjusting the rotor displacement signal and the current signal. Fig. 9It is the suspension power output circuit of the suspension power board. The PWM signal sent by the FPGA is isolated by an optocoupler and converted into a +5V level. The +5V level signal enters the suspension drive chip U312, driving the full-bridge circuit composed of power MOS tubes Q31, Q32, Q33, and Q34, and then controls the suspension coil. On the right is the current sensor for measuring the winding of the U3 circuit, which is used to detect the coil current. The current data obtained is transmitted to the suspension CPU chip, and the current loop is closed-loop regulated internally to keep the current within a safe range (<4A) to prevent overcurrent from burning the coil.

[0041] The rotating power board is used to drive the rotating coil and detect the rotor position through the Hall sensor to realize the rotation function of the motor, including the Hall sensor processing circuit and the rotating power output circuit.

[0042] Fig.10 It is a Hall sensor processing circuit. Three Hall sensors are connected to the Hall sensor processing circuit. The switch signal is sent to the rotating CPU chip through the optical coupler as the feedback signal of the motor rotation. Fig.11 For the rotating power output circuit, the PWM signal emitted by the FPGA is sent to the rotating drive chip through an optocoupler. The drive chip is used to drive the MOS tube. This part of the circuit is consistent with the suspension power part, which can reduce the complexity of the system and the complexity of materials.

[0043] The rotating power board also includes a motor stator temperature detection circuit, such as Fig.12 As shown, it is used to detect the motor stator temperature. The two wires of the controller PT100 are connected to the motor stator temperature detection circuit to monitor the stator temperature and alarm when the stator temperature reaches 50℃. Fig.11 PT1 in the figure is an interface through which PT100 is connected to the motor stator temperature detection circuit.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the claims of the present invention.

Claims

1. A controller for an integrated magnetic levitation permanent magnet motor, characterized in that: It includes a main control board, an eddy current sensor processing circuit, a suspension power board, a rotating power board, and an input power supply; the suspension power board includes 4 groups of suspension coil driving hardware circuits, further including a suspension driving chip and a peripheral circuit, which are used to drive the suspension coil on the motor; the rotating power board includes a rotating coil driving hardware circuit, further including a rotating driving chip and a peripheral circuit, which are used to drive the rotating coil on the motor; the suspension driving chip is controlled by a suspension CPU on the main control board sending a driving signal to drive the suspension coil to form a suspension magnetic field; the rotating driving chip is controlled by a rotation CPU on the main control board sending a driving signal to drive the rotating coil to form a rotating magnetic field; the two controls are decoupled from the hardware; the eddy current sensor processing circuit is used to process the rotor displacement signal measured by the eddy current sensor and transmit it to the main control board; the suspension coil and the rotating coil share a group of input power supplies, and the input power supply is a switching power supply integrated on the mechanical sheet metal inside the controller.

2. The controller for an integrated magnetic levitation permanent magnet motor according to claim 1, characterized in that: The main control board includes a PWM sending chip FPGA system circuit, a suspension main control circuit, a rotation main control circuit, a communication chip system circuit, a current sensor processing circuit, and an eddy current sensor secondary processing circuit; The PWM emitter chip FPGA system circuit includes crystal oscillator circuit, boot, download circuit, and external FLASH circuit, so that the FPGA can work normally; The suspension main control circuit and FPGA system circuit form a suspension function; the suspension main control circuit includes a suspension CPU chip, a crystal oscillator circuit, a boot, a download circuit, and an external FLASH circuit; the ADC shares 10 channels to collect current data and rotor displacement data, 12 PWM pins to communicate with the FPGA, CAN pins to communicate with the host computer and the communication chip, and other necessary pins and circuits; The rotation main control circuit realizes the rotation function of the motor and generates a PWM signal, including a rotation CPU chip and a crystal oscillator circuit, a boot circuit, and a download circuit; The communication chip system circuit is used to realize the communication with the suspension CPU chip, the rotating CPU chip, the touch screen and the customer's host computer. As an information transfer station, it sends instructions to the two CPU chips; it communicates with the DSP through the CAN interface, and communicates with the rotating chip through UART; it communicates with the touch screen through the RS232 interface; and it communicates with the customer's host computer through ETHERCAT; The current sensor processing circuit is used to collect the current signal of the current sensor and transmit it to the suspended CPU chip after processing; the current sensor signal is amplified by the circuit operational amplifier, filtered by the resistor and inductor, and finally protected by the bidirectional diode AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V; The eddy current sensor secondary processing circuit is used to perform secondary processing on the signal of the eddy current sensor processing circuit and transmit it to the suspended CPU chip. The signal transmitted by the eddy current sensor processing circuit is amplified by an operational amplifier and filtered by a resistor and inductor. Finally, a bidirectional diode is used to protect the AD pin of the suspended CPU chip to prevent the sampling voltage from being greater than 3.3V.

3. The controller for an integrated magnetic levitation permanent magnet motor according to claim 2, characterized in that: The eddy current sensor processing circuit forms a resonant circuit through a transistor, an operational amplifier, an inductor, and a capacitor to make the eddy current sensor oscillate; subsequently, the AC signal is converted into a DC signal through a detection circuit, and then the signal is amplified by the operational amplifier and transmitted to the main control board for processing.

4. The controller for an integrated magnetic levitation permanent magnet motor according to claim 2, characterized in that: The suspension power board is used to drive the suspension coil, and the rotor is suspended by adjusting the rotor displacement signal and the current signal together; the PWM signal sent by the FPGA is isolated by an optical coupler and converted into a +5V level, and the +5V level signal enters the suspension drive chip to drive the full-bridge circuit composed of power MOS tubes Q31, Q32, Q33, and Q34, thereby controlling the suspension coil. The current sensor measures the winding of the current sensor U3 circuit to detect the coil current size, and the obtained current data is transmitted to the suspension CPU chip, and the current loop closed-loop adjustment is performed internally to keep the current within a safe range of less than 4A.

5. The controller for an integrated magnetic levitation permanent magnet motor according to claim 2, characterized in that: The rotating power board is used to drive the rotating coil, detect the rotor position through the Hall sensor, and realize the rotation function of the motor, including a Hall sensor processing circuit and a rotating power output circuit; The Hall sensor processing circuit connects three Hall sensors to the Hall sensor processing circuit, and sends the switch signal to the rotating CPU chip through the optocoupler as the feedback signal of the motor rotation; the rotating power output circuit sends the PWM signal emitted by the FPGA to the rotating drive chip through the optocoupler, and the drive chip is used to drive the MOS tube.

6. The controller for an integrated magnetic levitation permanent magnet motor according to claim 5, characterized in that: The rotating power board also includes a motor stator temperature detection circuit. Two wires of an external controller PT100 for monitoring the temperature of the motor stator coil are connected to the motor stator temperature detection circuit to monitor the stator temperature and issue an alarm when the stator temperature reaches 50°C.

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