Motor rotor position acquisition device and method, chip and motor controller

Abstract

The invention discloses a motor rotor position obtaining device and method, a chip and a motor controller, the device comprises an IO module and a control module, the IO module comprises a plurality of IO ports, the plurality of IO ports are in one-to-one correspondence with multi-phase bridge arms, the plurality of IO ports are respectively used for obtaining level signals corresponding to dead zone voltage of the corresponding phase bridge arms in dead zone time, and the control module is used for controlling the IO ports to be in one-to-one correspondence with the level signals of the corresponding phase bridge arms in one-to-one correspondence with the level signals of the corresponding phase bridge arms in one-to-one correspondence with the level signals of the corresponding phase bridge arms. In the dead zone time, the upper bridge arm switch tube and the lower bridge arm switch tube of the corresponding phase bridge arm are respectively disconnected, and the voltage generated by the current flowing through the freewheeling diode on the corresponding phase bridge arm is the dead zone voltage; and the control module is connected with the plurality of IO ports and is used for determining the position of the motor rotor based on the level signal. The device can realize a high-reliability motor rotor position acquisition function without a sensor.

Description

Technical Field

[0001] The present invention relates to the field of chip design, and in particular to a device and method for obtaining the position of a motor rotor, a chip, and a motor controller. Background Art

[0002] In chips involving motor control, sensors (such as Hall sensors and magnetic encoders) are usually used to monitor and feedback the motor rotor position, motor phase current and other operating parameters in real time, so as to control the motor current and direction, and then adjust the motor speed and position to achieve real-time control of the motor. In practical applications, due to the high cost of sensors, they cannot be widely used. Therefore, the related technology usually adopts the sliding film and Lomborg sensorless observer to obtain the motor rotor position. This method estimates the motor rotor position by measuring the motor's inductance, resistance and magnetic flux and other parameters to achieve the function of determining the motor rotor position.

[0003] The disadvantage of the above-mentioned related technologies is that the electronic rotor position determination method requires measuring multiple parameters such as the motor's magnetic flux, and requires complex arctan, sin and cos operations on these parameters. Therefore, the algorithm is relatively complex and requires high chip computing power, resulting in the corresponding motor control cost of this method is still high. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the first purpose of the present invention is to propose a motor rotor position acquisition device, by setting a control module and an IO module including multiple IO ports in the device, during the dead time of the motor controller, the multiple IO ports can obtain the level signal corresponding to the dead voltage of the corresponding phase bridge arm, and then the control module can determine the motor rotor position based on the obtained level signal, thereby realizing the function of obtaining the motor rotor position without the need for a sensor, and at the same time, the determination logic of the rotor position is simple, and there is no need to measure the inductance, magnetic flux and other parameters of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of obtaining the motor rotor position.

[0005] The second objective of the present invention is to provide a chip.

[0006] The third objective of the present invention is to provide a motor controller.

[0007] A fourth objective of the present invention is to provide an electrical device.

[0008] A fifth objective of the present invention is to provide a method for acquiring the position of a motor rotor.

[0009] A sixth object of the present invention is to provide a computer-readable storage medium.

[0010] To achieve the above-mentioned purpose, the first aspect of the present invention proposes a motor rotor position acquisition device, which is applied to a motor controller. The motor controller includes a multi-phase bridge arm, and the multi-phase bridge arm includes an upper bridge arm and a lower bridge arm respectively. The upper bridge arm includes an upper bridge arm switch tube connected in parallel with a freewheeling diode, and the lower bridge arm includes a lower bridge arm switch tube connected in parallel with a freewheeling diode. The device includes: an IO module, the IO module includes multiple IO ports, and the multiple IO ports correspond one-to-one to the multi-phase bridge arms. The multiple IO ports are respectively used to obtain the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm during the dead zone time, wherein, during the dead zone time, the upper bridge arm switch tube and the lower bridge arm switch tube of the corresponding phase bridge arm are respectively disconnected, and the voltage generated on the corresponding phase bridge arm by the current flowing through the freewheeling diode is the dead zone voltage; a control module, the control module is connected to the multiple IO ports, and the control module is used to determine the motor rotor position based on the level signal.

[0011] According to the motor rotor position acquisition device of the embodiment of the present invention, a control module and an IO module including multiple IO ports are set in the device. During different dead time periods of the motor controller, the multiple IO ports can acquire level signals corresponding to the dead voltages of the corresponding phase bridge arms. Subsequently, the control module can determine the motor rotor position based on the acquired level signals, thereby realizing the function of acquiring the motor rotor position without the need for sensors. Meanwhile, the determination logic of the rotor position is simple, and there is no need to measure parameters such as the inductance and magnetic flux of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0012] According to one embodiment of the present invention, the control module is also used to switch the working mode of the corresponding IO port from the analog input mode to the IO input mode at the beginning of the dead zone of each phase bridge arm, and to switch the working mode of the corresponding IO port from the IO input mode to the analog input mode at the end of the dead zone of each phase bridge arm, so that the IO port obtains the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm within the dead zone time.

[0013] According to an embodiment of the present invention, the control module is specifically used to determine the motor rotor position at the rising edge or the falling edge of the level signal.

[0014] According to an embodiment of the present invention, the control module is specifically configured to determine the motor rotor position when the level signal switches from a high level signal to a low level signal, or switches from a low level signal to a high level signal.

[0015] According to an embodiment of the present invention, the control module is further configured to generate and output an interrupt signal when the motor rotor position is determined, so as to control the motor based on the interrupt signal.

[0016] According to an embodiment of the present invention, the control module is further configured to generate a position signal and store it in a register when the position of the motor rotor is determined, so as to control the motor based on the position signal in the register.

[0017] According to an embodiment of the present invention, the control module is further configured to perform open-loop control on the motor using a constant voltage-frequency ratio or a constant current-frequency ratio.

[0018] To achieve the above-mentioned purpose, a second embodiment of the present invention provides a chip, including the aforementioned motor rotor position acquisition device.

[0019] According to the chip of the embodiment of the present invention, through the aforementioned motor rotor position acquisition device, the function of acquiring the motor rotor position can be realized without a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's inductance, magnetic flux and other parameters, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0020] To achieve the above-mentioned purpose, a third aspect of the present invention provides a motor controller, including the aforementioned motor rotor position acquisition device.

[0021] According to the motor controller of the embodiment of the present invention, through the aforementioned electronic rotor position acquisition device, the function of acquiring the motor rotor position can be realized without sensors, and there is no need to measure the motor's inductance, magnetic flux and other parameters, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0022] To achieve the above-mentioned purpose, a fourth aspect of the present invention provides an electrical device, including the aforementioned motor rotor position acquisition device, or the aforementioned chip, or the aforementioned motor controller.

[0023] According to the electrical equipment of the embodiment of the present invention, through the aforementioned motor rotor position acquisition device, or the aforementioned chip, or the aforementioned motor controller, the function of acquiring the motor rotor position can be realized without the need for a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's inductance, magnetic flux and other parameters, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0024] To achieve the above-mentioned purpose, the fifth aspect of the present invention proposes a method for obtaining the position of a motor rotor, which is applied to a motor controller. The motor controller includes a multi-phase bridge arm, and the multi-phase bridge arm includes an upper bridge arm and a lower bridge arm respectively. The upper bridge arm includes an upper bridge arm switch tube connected in parallel with a freewheeling diode, and the lower bridge arm includes a lower bridge arm switch tube connected in parallel with a freewheeling diode. The method includes: obtaining a level signal corresponding to a dead zone voltage of a target bridge arm within a dead zone time, wherein, within the dead zone time, the upper bridge arm switch tube and the lower bridge arm switch tube of the target bridge arm are respectively disconnected, and the voltage generated on the target bridge arm by the current flowing through the freewheeling diode is the dead zone voltage; based on the level signal, determining the position of the motor rotor.

[0025] According to the motor rotor position acquisition method of an embodiment of the present invention, a level signal corresponding to the dead zone voltage of the target bridge arm within the dead zone time of the motor controller is obtained, and then the motor rotor position is determined based on the obtained multiple level signals, thereby realizing the function of acquiring the motor rotor position without the need for a sensor. At the same time, the determination logic of the rotor position is simple, and there is no need to measure the inductance, magnetic flux and other parameters of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0026] To achieve the above-mentioned purpose, a sixth aspect of the present invention proposes a computer-readable storage medium having a program stored thereon, which implements the aforementioned method for obtaining the motor rotor position when executed by a processor.

[0027] According to the computer-readable storage medium of an embodiment of the present invention, through the aforementioned motor rotor position acquisition method, the function of acquiring the motor rotor position can be realized when the motor is working without the need for a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's inductance, magnetic flux and other parameters, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0028] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic structural diagram of a motor controller according to an embodiment of the present invention;

[0030] Figure 2 2 is a schematic diagram of the structure of a device for acquiring the position of a motor rotor according to an embodiment of the present invention;

[0031] Figure 3 is a control timing diagram of corresponding phase bridge arms according to an embodiment of the present invention;

[0032] Figure 4a to Figure 4bA schematic diagram of current direction of a motor controller according to an embodiment of the present invention;

[0033] Figure 5 is a structural schematic diagram of a single-ended voltage sampling circuit according to an embodiment of the present invention;

[0034] Figure 6a to Figure 6b A schematic diagram of current direction of a single-ended voltage sampling circuit according to an embodiment of the present invention;

[0035] Figure 7 Schematic diagram of a dead zone voltage waveform of a U-phase bridge arm according to an embodiment of the present invention;

[0036] Figure 8 is a schematic diagram of a dead zone voltage and a phase current of a motor controller according to an embodiment of the present invention;

[0037] Fig. 9 is a waveform diagram of an interrupt signal according to an embodiment of the present invention;

[0038] Fig.10 is a schematic structural diagram of a chip according to an embodiment of the present invention;

[0039] Fig.11 is a schematic structural diagram of a motor controller according to an embodiment of the present invention;

[0040] Figure 12a to Figure 12c A schematic diagram of the structure of an electrical device according to an embodiment of the present invention;

[0041] Fig.13 The figure is a flow chart of a method for acquiring the motor rotor position according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0043] The following describes a motor rotor position acquisition device and method, a chip, a motor controller, an electrical device, and a computer-readable storage medium proposed in an embodiment of the present invention with reference to the accompanying drawings.

[0044] It should be noted that the motor rotor position acquisition device of the embodiment of the present invention can be applied to a motor controller with a multi-phase bridge arm. Figure 1 As an example, refer to the motor controller shown in Figure 1As shown, the motor controller 100 includes three-phase bridge arms, namely, a U-phase bridge arm, a W-phase bridge arm and a V-phase bridge arm, which are connected to the U-phase, W-phase and V-phase of the motor M. Each phase bridge arm includes an upper bridge arm and a lower bridge arm, and the upper bridge arms of the three-phase bridge arms are all connected to the DC bus power supply VBUS, and the lower bridge arms of the three-phase bridge arms are all grounded GND. The upper bridge arm also includes an upper bridge arm switch tube QU with a freewheeling diode in parallel, and the lower bridge arm also includes a lower bridge arm switch tube QD with a freewheeling diode in parallel.

[0045] Specifically, refer to Figure 1 As shown, the motor controller 100 constitutes a typical three-phase inverter circuit. By controlling the on-off of the six switching tubes in the three-phase bridge arm, the motor controller 100 can convert the DC power provided by the DC bus power supply VBUS into three-phase AC power, and then control the rotation of the motor M to realize the control function of the motor. The control logic can be a variety of control logics such as two-by-two conduction, three-by-three conduction, etc. The specific control logic is not expanded here.

[0046] Figure 2 FIG. 1 is a schematic diagram of a motor rotor position acquisition device according to an embodiment of the present invention. Figure 2 As shown, the device 200 includes: an IO module 210 and a control module 220 .

[0047] Among them, the IO module 210 includes multiple IO ports 211, and the multiple IO ports 211 correspond one-to-one to the multi-phase bridge arms. The multiple IO ports 211 are respectively used to obtain the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm during the dead zone time, wherein, during the dead zone time, the upper bridge arm switch tube QU and the lower bridge arm switch tube QD of the corresponding phase bridge arm are respectively disconnected, and the voltage generated by the current flowing through the freewheeling diode on the corresponding phase bridge arm is the dead zone voltage; the control module 220 is connected to the multiple IO ports 211, and the control module 220 is used to determine the motor rotor position based on the level signal.

[0048] Specifically, Figure 2 The one-phase bridge arm shown can be Figure 1 One phase of the U-phase bridge arm, W-phase bridge arm and V-phase bridge arm shown. In the control process of the motor controller 100 on the motor M, in order to realize the phase change function of the motor M, a phase in the three-phase bridge arm needs to switch the upper bridge arm switch tube QU and the lower bridge arm switch tube QD. At this time, the phase bridge arm is the corresponding phase bridge arm. In order to avoid the upper and lower bridge arm switches of the corresponding phase bridge arm being turned on at the same time, causing damage to the motor controller 100, it is necessary to set a period of time as a dead time before switching on, such as Figure 3The t0-t1 period and the t2-t3 period are shown. Ensure that the upper bridge arm switch tube QU and the lower bridge arm switch tube QD in the phase bridge arm are disconnected respectively before the conduction switching function is performed to protect the safety of the motor controller 100. From the above analysis, it can be seen that during the dead time of the motor controller 100, the bridge arm where the upper bridge arm switch tube QU and the lower bridge arm switch tube QD are both disconnected is the corresponding phase bridge arm.

[0049] In a single control cycle of the motor controller 100, each bridge arm needs to be switched, so the number of IO ports 211 in the IO module 210 should be the same as the number of phases in the motor controller 100, so that when each bridge arm serves as the corresponding phase bridge arm, the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm is collected. For example, when the device 200 is used in the motor controller 100, the number of IO ports 211 is 3. The following takes the U-phase bridge arm as the corresponding phase bridge arm as an example to illustrate the level signal collection function of the IO port 211. During the dead zone time of the U-phase bridge arm, although the upper bridge arm switch tube QU and the lower bridge arm switch tube QD are turned off respectively, since these two switch tubes have freewheeling diodes, different freewheeling circuits will be generated in the U-phase bridge arm according to the size of the phase voltage of the U phase. The voltage generated on the upper bridge arm or the lower bridge arm by the current flowing through the freewheeling diode at this time can be obtained in a variety of ways. This voltage is the dead zone voltage. Among them, reference Figure 4a As shown, when the current of the freewheeling circuit flows through the upper bridge arm, the current direction at this time is from the U phase of the motor through the freewheeling diode of the upper bridge arm switch tube DU to the DC bus power supply VBUS. Therefore, the dead zone voltage at this time is higher than the DC bus voltage VBUS, and the corresponding level signal obtained by the IO port 211 can be a high level; or, refer to Figure 4b As shown, when the current of the freewheeling loop flows through the lower bridge arm, the current direction at this time is from the ground terminal GND through the freewheeling diode of the lower bridge arm switch tube QD into the U phase of the motor. At this time, the dead zone voltage is lower than zero, and the corresponding level signal obtained through the IO port 211 may be a low level. It can be seen that during the dead zone time, different freewheeling loops will be generated in the corresponding phase bridge arm according to the phase voltage of the corresponding phase of the corresponding phase bridge arm. At this time, the level signal obtained by the corresponding IO port 211 will also be divided into high level and low level. Subsequently, the control module 220 can determine whether the freewheeling loop in the motor controller 100 is based on the corresponding level signal detected by the IO port. Figure 4a and Figure 4b One of the freewheeling circuits shown is used to determine the commutation moment of the motor M at this time. In the control logic of the motor M, the motor rotor position corresponding to the fixed commutation moment is also fixed. Therefore, the control module 220 can determine the corresponding motor rotor position according to the level signal obtained by the IO port 211.

[0050] As can be seen from the above, the acquisition device 200 of the embodiment of the present invention can detect the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm in the motor controller 100 within the dead zone time of the motor controller 100 to determine the rotor position of the motor M. Compared with the method of using the sliding film and the Lomborg sensorless observer to determine the motor rotor position in the related art, the acquisition device 200 of the embodiment of the present invention only needs to obtain the level signal corresponding to the dead zone voltage as a measurement parameter, and does not need to measure the inductance and resistance and flux linkage parameters of the motor M. Therefore, the acquisition device 200 can be applied to surface-mounted motors and salient pole motors, and is not sensitive to temperature parameters. It can work normally in an ambient temperature of -40° to 130°, and has high reliability and applicability; at the same time, the logic of the acquisition process of the motor rotor position by the acquisition device 100 is relatively simple, and neither complex arctan, sin and cos operations nor floating-point data are required. Therefore, the acquisition device 200 has low requirements on the computing power and performance of the chip, and the error probability is also low. Therefore, the acquisition device of the embodiment of the present invention has the advantages of simple logic, high reliability and low error rate. In addition, compared with the method of using a sensor to obtain the motor rotor position, the acquisition device in the embodiment of the present invention also has the advantage of low cost.

[0051] In the above embodiment, by setting a control module and an IO module including multiple IO ports in the device, within different dead time periods of the motor controller, the multiple IO ports can obtain level signals corresponding to the dead voltages of the corresponding phase bridge arms. Subsequently, the control module can determine the motor rotor position based on the obtained level signals, thereby realizing the function of obtaining the motor rotor position without the need for sensors. At the same time, the logic for determining the rotor position is simple, and there is no need to measure parameters such as the inductance and magnetic flux of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of obtaining the motor rotor position.

[0052] In some embodiments, the control module 220 is also used to switch the working mode of the corresponding IO port 211 from the analog input mode to the IO input mode at the beginning of the dead zone of each phase bridge arm, and to switch the working mode of the corresponding IO port from the IO input mode to the analog input mode at the end of the dead zone of each phase bridge arm, so that the IO port 211 obtains the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm within the dead zone time.

[0053] Specifically, the IO port 211 may have two working modes, namely, analog input mode and IO input mode. Among them, when the dead time of each phase bridge arm of the motor controller 100 begins, the control module 220 may control the IO port 211 corresponding to the corresponding phase bridge arm to enter the IO input mode. At this time, the IO port 211 may convert the voltage with a higher input voltage into a high-level signal, and convert the voltage with a lower input voltage into a low-level signal, and output the level signal to the control module 220. When the dead time of each phase bridge arm of the motor controller 100 ends, the control module 220 may control multiple IO ports 211 to switch to the analog input mode. At this time, the IO port 211 may realize other functions, such as collecting the phase voltage of each phase, so as to monitor the motor operating parameters in real time. In this way, the multiplexing of the IO port is realized, and the hardware cost of the motor rotor position acquisition device is reduced.

[0054] Optional, reference Figure 5 As shown, the IO port 211 can obtain the dead zone voltage of the corresponding phase bridge arm during the dead zone time through the single-ended sampling circuit 300, and convert it into a corresponding level signal and output it to the control module 220. Among them, the single-ended voltage sampling circuit 300 may include three identical single-ended sampling sub-circuits 310, and the three sampling ends of the single-ended sampling sub-circuit 310 are respectively connected to the JU, JW, and JV nodes of the motor controller 100, wherein the JU, JW, and JV nodes are the output ends of the corresponding phase alternating current of the motor controller 100, and the three sampling points (Vbemf_U, Vbemf_V, and Vbemf_W) of the single-ended sampling sub-circuit 310 are respectively connected to the corresponding IO port 211. The circuit structures of the three single-ended sampling sub-circuits 310 are the same. Taking the single-ended sampling sub-circuit 310 of the U-phase bridge arm as an example, the circuit 310 includes a first resistor to a third resistor R1~R3 ​​and a capacitor C, wherein one end of the first resistor R1 is grounded GND, and the other end of the first resistor R1 is respectively connected to one end of the second resistor R2 and one end of the third resistor R3; the other end of the second resistor R2 is connected to the node JU as a sampling end; the other end of the third resistor R3 is connected to one end of the capacitor C and serves as the voltage sampling point Vbemf_U of the single-ended voltage sampling circuit 300, and the other end of the capacitor C is grounded GND. The circuit mainly collects the upper bridge arm or lower bridge arm voltage of the U-phase bridge arm as the dead zone voltage according to the voltage division principle of the first resistor R1 and the second resistor R2. At the same time, the capacitor C has a voltage stabilizing effect, and the third resistor R3 has a current limiting effect to avoid excessive current in the single-ended voltage sampling circuit 300.

[0055] When the single-ended voltage sampling circuit 300 is Figure 5As shown, the process of obtaining the dead zone voltage of the corresponding phase bridge arm of the motor controller 100 is as follows: when the U-phase bridge arm is the corresponding phase bridge arm, according to the high or low phase voltage of the U-phase of the motor M, there are two situations in the freewheeling circuit on the U-phase bridge arm. In the first situation, the U-phase voltage is high, and there is current in the upper bridge arm of the U-phase bridge arm. At this time, the current path in the single-ended voltage sampling circuit 300 is as follows: Figure 6a As shown, one current path starts from the JU node, passes through the second resistor R2 and the first resistor R1 to the ground terminal GND, and the other current path starts from the JU node, passes through the second resistor R2 and the third resistor R3 to the corresponding IO port 211. At this time, according to the voltage division principle, the following formula (1) can be obtained:

[0056] Vbemf_U=VU*R1 / (R2+R2) (1)

[0057] Wherein, Vbemf_U is the sampled voltage collected by the single-ended voltage sampling circuit 300; VU is the voltage generated in the upper bridge arm by the current flowing through the freewheeling diode, i.e., the dead zone voltage; R1 is the resistance value of the first resistor R1, and R2 is the resistance value of the second resistor R2. The dead zone voltage VU of the U-phase bridge arm at this time can be obtained by the above formula (1).

[0058] Alternatively, in the second case, the U phase voltage is low, and there is current in the lower bridge arm of the U phase bridge arm. At this time, the current path in the motor controller 100 is as follows: Figure 6b As shown, one current path starts from the ground terminal GND, passes through the first resistor R1 and the second resistor R2 to the JU node; the other current path starts from the ground terminal GND, passes through the first resistor R1 and the third resistor R3 to the corresponding IO port 211. At this time, the dead zone voltage VU can also be obtained according to the above formula (1).

[0059] It should be noted that the motor rotor position acquisition device 200 of the embodiment of the present invention may also adopt other methods to acquire the dead zone voltage of the corresponding phase bridge arm. Figure 5 The single-ended voltage sampling circuit 300 shown is exemplary and is not intended to limit the present application.

[0060] Furthermore, the level signal conversion logic of the IO port 211 can be set as follows: when the input voltage of the IO port is higher than the DC bus voltage VBUS, the IO port outputs a high level signal; when the input voltage of the IO port is less than or equal to 0, the IO port outputs a low level signal.

[0061] Specifically, assuming that the U-phase bridge arm is the corresponding phase bridge arm, during the dead time of the motor controller 100, when the freewheeling circuit of the U-phase bridge arm is as follows: Figure 4a When shown, the following formula (2) can be obtained based on the voltage division principle:

[0062] VU=VBUS+Vd (2)

[0063] Among them, VU is the dead zone voltage of the U-phase bridge arm, VBUS is the DC bus voltage of the motor controller 100, which can be obtained through real-time detection; Vd is the diode conduction voltage, which can be obtained by obtaining the diode parameters.

[0064] When the freewheeling circuit in the motor controller 100 is Figure 4b When shown, the following formula (3) can be obtained based on the voltage division principle:

[0065] VU=0-Vd (3)

[0066] Among them, VU is the dead zone voltage of the U-phase bridge arm, and Vd is the diode conduction voltage, which can be obtained by obtaining the diode parameters.

[0067] It can be seen that in the motor controller 100, the dead zone voltage of the corresponding phase bridge arm fluctuates between -Vd and VBUS+Vd. Therefore, the conversion logic of the level signal of the IO port 211 can be set to: when the input voltage of the IO port 211 is higher than the DC bus voltage VBUS, the IO port 211 outputs a high level signal, and when the input voltage of the IO port 211 is less than or equal to 0, the IO port 211 outputs a low level signal. In this way, the IO port realizes the function of obtaining the level signal corresponding to the dead zone voltage.

[0068] As a specific example, in the motor controller 100, the dead zone voltage waveform of the U-phase bridge arm collected by the single-ended voltage sampling circuit 300 during the dead zone time is as follows: Figure 7 Reference Figure 7 As shown, the waveform is composed of high voltage and low voltage that switch periodically, and the waveform is neat and the switching moments of high and low level signals are obvious. Therefore, the high voltage in the waveform can be converted into a high level and the low voltage can be converted into a low level through the IO port 211 to serve as a Hall signal to determine the rotor position of the motor.

[0069] In some embodiments, the control module 220 is specifically configured to determine the motor rotor position at a rising edge or a falling edge of the level signal.

[0070] Specifically, refer to Figure 7 As shown, during the control cycle of the motor controller 100, the dead zone voltage of the corresponding phase bridge arm will jump between high voltage and low voltage, and the level signal output by the corresponding IO port 211 will jump between high level and low level. At this time, the change curve of the level signal corresponding to the three-phase bridge arm can be determined in combination with the control logic of the motor M. For example, when the motor is controlled in a three-three conduction mode, the level signal changes corresponding to the three-phase current of the motor M and the dead zone voltage of the corresponding phase bridge arm can be as follows: Figure 8 As shown. Figure 8Taking the U-phase bridge arm shown in the figure as an example, when the dead zone voltage of the U-phase bridge arm switches between a high level signal and a low level signal, it means that the upper and lower bridge arm switches of the bridge arm are switched, so that the motor M is switched. In one control cycle, that is, Figure 8 In the range of 0° to 360° shown in the figure, the U-phase bridge arm has undergone two high-low level switchings, and the falling edge or rising edge of the switching is the dead time. During the dead time, the U-phase current passes through the zero point, and in different motor control logics, the zero point corresponds to the phase change, so the motor rotor position corresponding to the zero point is fixed. Figure 8 As shown, the U-phase current passes through the zero point twice, and in a single control cycle of the motor controller 100, each phase needs to undergo two phase changes, a total of six phase changes, that is, one phase change every 60°, refer to Figure 8 As shown, the two zero crossing points of the U-phase current are the second and fifth times, and the corresponding motor rotor positions should be 60° and 240°, wherein the motor rotor position corresponding to the falling edge of the U-phase dead zone voltage is 60°, and the motor rotor position corresponding to the rising edge of the U-phase dead zone voltage is 240°, and the motor rotor positions of the remaining phases are analogous. Therefore, when the control module 220 determines that the level signal corresponding to the dead zone voltage of the U-phase bridge arm during the dead zone time is a rising edge or a falling edge, the motor rotor position at this time can be determined.

[0071] Furthermore, the control module 220 is specifically configured to determine the motor rotor position when the level signal switches from a high level signal to a low level signal, or switches from a low level signal to a high level signal.

[0072] Specifically, refer to Figure 8 As shown, during the dead time, when the control module 220 detects that the level signal corresponding to the dead zone voltage of the U-phase bridge arm switches from a high level signal to a low level signal, the freewheeling current in the U-phase of the motor will be Figure 4a The direction shown becomes Figure 4b The direction shown indicates that the commutation time of motor M has arrived. Figure 8 The falling edge position of the U-phase dead zone voltage shown in FIG. 1 can determine that the motor rotor position at this time is 60°; when the control module 220 detects that the level signal corresponding to the dead zone voltage of the U-phase bridge arm switches from a low level signal to a high level signal, it indicates that the commutation time of the motor M has arrived. Figure 8 The rising edge position of the U-phase dead zone voltage shown can determine that the motor rotor position at this time is 240°.

[0073] As a result, the control module realizes the function of determining the motor rotor position based on the level signal output by the IO module.

[0074] It should be noted that when the V-phase bridge arm and the W-phase bridge arm are corresponding phase bridge arms, the method for determining the motor rotor position is similar to the method for determining the U-phase bridge arm described above, and will not be described in detail here. In addition, since the acquisition device 200 of the embodiment of the present invention only works within the dead time of the motor controller 100, the sampling frequency of the acquisition device 200 can be set based on the dead time of the motor controller 100. For example, when the motor controller 100 works in a three-three conduction mode, each phase bridge arm performs two phase changes in a single control cycle. Therefore, the sampling frequency of the acquisition device 200 can be set to twice the control frequency. For example, when the control frequency of the motor controller 100 is 16KHZ, the sampling frequency of the acquisition device 200 can be 32KHZ, which can achieve the effect of determining the motor rotor position within the dead time.

[0075] In some embodiments, the control module 220 is further configured to generate and output an interrupt signal when the motor rotor position is determined, so as to control the motor based on the interrupt signal.

[0076] Specifically, when the motor rotor position is determined, the control module 220 may assume part of the control function of the motor M, that is, provide an interrupt signal to the external controller of the motor. The generated interrupt signal may be as follows: Fig. 9 As shown, reference Fig. 9 As shown, within one cycle, the control module 220 can generate 6 interrupt signals according to the motor rotor position, and output them in the form of increasing square waves, corresponding to Fig. 9 As shown in 0 to 5, the external controller of the motor M can determine the current motor rotor position based on the interrupt signal and perform 6 phase changes, which is equivalent to a phase change every 60°, to achieve the control function of the motor, so that

[0077] The position signal is stored in the register so that the motor can be controlled based on the position signal in the register.

[0078] Specifically, when determining the motor rotor position, the control module 220 can also generate a position signal based on the determined rotor position and store it in a register. The register has the characteristics of easy storage and reading. Therefore, the external controller of the motor M can easily read the position signal from the register to control the motor M based on the position signal in the register, thereby further reducing the control cost of the motor.

[0079] In some embodiments, the control module 220 is further configured to perform open-loop control on the motor using a constant voltage-frequency ratio or a constant current-frequency ratio.

[0080] Specifically, the constant voltage-frequency ratio and the constant current-frequency ratio are both VF open-loop control modes. When the motor is started through the VF open-loop control method and runs smoothly to the target speed, the voltage, current and back electromotive force of the motor are in a balanced state, and the current phase difference of the motor controller 100 has a stable relationship with the phase difference of the rotor position. At this time, determining the rotor position by detecting the current zero crossing point can make the determined rotor position more accurate. Therefore, when the motor is open-loop controlled using a constant voltage-frequency ratio or a constant current-frequency ratio, the motor rotor position determined by the acquisition device of the embodiment of the present invention is more accurate, thereby improving the accuracy of the acquisition device.

[0081] Optionally, when the VF open-loop control mode is used to control the motor M, the control module 220 can also calculate the phase difference between the motor's back electromotive force and the current in the steady state based on the motor's voltage equation, so as to correct the determined motor rotor position, thereby making the electronic rotor position determination more accurate, thereby improving the motor's operating efficiency.

[0082] Optionally, the control module 220 is further configured to perform interpolation processing on the motor rotor position to obtain the interpolated motor rotor position.

[0083] Specifically, interpolation processing refers to processing multiple sets of motor rotor position data using an interpolation method. The motor rotor position processed by the interpolation method can correct the error in the process of determining the motor rotor position, thereby improving the accuracy of the determined motor rotor position.

[0084] In summary, according to the electronic rotor acquisition device of the embodiment of the present invention, by using multiple IO ports to obtain the level signal corresponding to the dead-zone voltage of the corresponding phase bridge arm during the dead-zone time of the motor controller, and then determining the motor rotor position based on the obtained level signal through the control module, the function of obtaining the motor rotor position is realized without the need for a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the inductance, magnetic flux and other parameters of the motor. In addition, the control module can also send an interrupt signal or generate a position signal and write it into a register when determining the motor rotor position, so that the external controller of the motor can obtain the rotor position of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of obtaining the motor rotor position.

[0085] Corresponding to the above embodiment, the embodiment of the present invention further provides a chip, referring to Fig.10 As shown, the chip 1000 includes the aforementioned motor rotor position acquisition device 200 .

[0086] According to the chip of the embodiment of the present invention, through the aforementioned motor rotor position acquisition device, it is possible to realize the function of acquiring the motor rotor position when the motor is working without the need for a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's parameters such as inductance and magnetic flux. In addition, when determining the motor rotor position, an interrupt signal can be sent or a position signal can be generated and written into a register to control the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0087] Corresponding to the above embodiment, the embodiment of the present invention further provides a motor controller, referring to Fig.11 As shown, the motor controller 2000 includes the aforementioned motor rotor position acquisition device 200 .

[0088] According to the motor controller of the embodiment of the present invention, through the aforementioned motor rotor position acquisition device, it is possible to realize the function of acquiring the motor rotor position when the motor is working without the need for a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's parameters such as inductance and magnetic flux. In addition, when determining the motor rotor position, an interrupt signal can be sent or a position signal can be generated and written into a register to control the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0089] Corresponding to the above embodiment, the embodiment of the present invention further provides an electrical device, referring to Fig.12a As shown, the electrical equipment 10000 includes the aforementioned motor rotor position acquisition device 200; or, referring to Figure 12b As shown, the electrical device 10000 includes the aforementioned chip 1000; or, referring to Fig.12c As shown, the electrical device 10000 includes the aforementioned motor controller 2000 .

[0090] The electrical equipment according to the embodiment of the present invention includes the motor rotor position acquisition device or chip and the motor controller in any of the above embodiments, wherein the electrical equipment can be various equipment such as air conditioners, refrigerators, compressors, etc. These electrical appliances can realize the function of acquiring the motor rotor position without a sensor when the motor is working through the aforementioned motor rotor position acquisition device, or the aforementioned chip, or the aforementioned motor controller, and send an interrupt signal or generate a position signal to write into a register when the motor rotor position is determined, so as to control the motor. At the same time, the determination logic of the rotor position is simple, and there is no need to measure the inductance, flux linkage and other parameters of the motor; in addition, when the motor rotor position is determined, an interrupt signal can be sent or a position signal can be generated to write into a register, so as to control the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0091] Corresponding to the above embodiment, the embodiment of the present invention further provides a method for obtaining the position of a motor rotor, which can be applied to Figure 1 In the motor controller 100 shown in FIG. Fig.13 As shown, the method includes:

[0092] S11, obtaining a level signal corresponding to the dead zone voltage of the target bridge arm during the dead zone time, wherein during the dead zone time, the upper bridge arm switch tube and the lower bridge arm switch tube of the target bridge arm are respectively disconnected, and the voltage generated on the target bridge arm by the current flowing through the freewheeling diode is the dead zone voltage.

[0093] S12, determining the motor rotor position based on the level signal.

[0094] It should be noted that the target bridge arm described in the motor rotor position acquisition method of the embodiment of the present invention is the corresponding phase bridge arm described in the electronic rotor position acquisition device of the aforementioned embodiment.

[0095] According to one embodiment of the present invention, the method also includes: switching the working mode of the corresponding IO port from the analog input mode to the IO input mode at the start of the dead zone of each phase bridge arm, and switching the working mode of the corresponding IO port from the IO input mode to the analog input mode at the end of the dead zone of each phase bridge arm, so that the IO port obtains the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm within the dead zone time.

[0096] According to an embodiment of the present invention, the method further includes: determining the motor rotor position at a rising edge or a falling edge of the level signal.

[0097] According to an embodiment of the present invention, the method further includes: determining the motor rotor position when the level signal switches from a high level signal to a low level signal, or from a low level signal to a high level signal.

[0098] According to an embodiment of the present invention, the method further includes: when the motor rotor position is determined, generating an interrupt signal and outputting the interrupt signal to the outside, so as to control the motor based on the interrupt signal.

[0099] According to an embodiment of the present invention, the method further comprises: when the position of the motor rotor is determined, generating a position signal and storing it in a register, so as to control the motor based on the position signal in the register.

[0100] According to an embodiment of the present invention, the method further comprises: performing open-loop control on the motor by adopting a constant voltage-frequency ratio or a constant current-frequency ratio.

[0101] It should be noted that, for the description of the motor rotor position acquisition method in the present application, please refer to the description of the motor rotor position acquisition device in the present application, and the details will not be repeated here.

[0102] According to the motor rotor position acquisition method of the embodiment of the present invention, a level signal corresponding to the dead zone voltage of the target bridge arm within the dead zone time of the motor controller is obtained, and then the motor rotor position is determined based on the obtained multiple level signals, thereby realizing the function of acquiring the motor rotor position without the need for a sensor. At the same time, the determination logic of the rotor position is simple, and there is no need to measure the inductance, magnetic flux and other parameters of the motor. In addition, an interrupt signal is issued or a position signal is generated and written into a register when determining the motor rotor position, so that the external controller of the motor can acquire the rotor position of the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0103] Corresponding to the above embodiment, an embodiment of the present invention further provides a computer-readable storage medium on which a program is stored. When the program is executed by a processor, the above-mentioned method for obtaining the motor rotor position is implemented.

[0104] According to the computer-readable storage medium of an embodiment of the present invention, through the aforementioned motor rotor position acquisition device, the function of acquiring the motor rotor position can be realized when the motor is working without a sensor. At the same time, the logic for determining the rotor position is simple, and there is no need to measure the motor's inductance, magnetic flux and other parameters; in addition, when determining the motor rotor position, an interrupt signal can be issued or a position signal can be generated and written into a register to control the motor, thereby effectively reducing the control cost of the motor and improving the reliability of the function of acquiring the motor rotor position.

[0105] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0106] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0107] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0108] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0109] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, 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 the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0110] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A motor rotor position acquisition device, characterized in that: Applied to a motor controller, the motor controller comprises a multi-phase bridge arm, the multi-phase bridge arm comprises an upper bridge arm and a lower bridge arm respectively, the upper bridge arm comprises an upper bridge arm switch tube connected in parallel with a freewheeling diode, the lower bridge arm comprises a lower bridge arm switch tube connected in parallel with a freewheeling diode, and the device comprises: An IO module, wherein the IO module comprises a plurality of IO ports, the plurality of IO ports correspond to the multi-phase bridge arms one by one, and the plurality of IO ports are respectively used to obtain a level signal corresponding to a dead zone voltage of a corresponding phase bridge arm within a dead zone time, wherein within the dead zone time, an upper bridge arm switch tube and a lower bridge arm switch tube of the corresponding phase bridge arm are respectively disconnected, and a voltage generated on the corresponding phase bridge arm by the current flowing through the freewheeling diode is the dead zone voltage; A control module is connected to the multiple IO ports, and the control module is used to determine the motor rotor position based on the level signal.

2. The device according to claim 1, characterized in that The control module is also used to switch the working mode of the corresponding IO port from the analog input mode to the IO input mode at the start of the dead zone of each phase bridge arm, and switch the working mode of the corresponding IO port from the IO input mode to the analog input mode at the end of the dead zone of each phase bridge arm, so that the IO port obtains the level signal corresponding to the dead zone voltage of the corresponding phase bridge arm within the dead zone time.

3. The device according to claim 1 or 2, characterized in that: The control module is specifically used to determine the motor rotor position at the rising edge or falling edge of the level signal.

4. The device according to claim 1 or 2, characterized in that: The control module is specifically used to determine the position of the motor rotor when the level signal is switched from a high level signal to a low level signal, or from the low level signal to the high level signal.

5. The device according to claim 1, characterized in that The control module is further configured to generate and output an interrupt signal when the motor rotor position is determined, so as to control the motor based on the interrupt signal.

6. The device according to claim 1, characterized in that The control module is further configured to generate a position signal and store the position signal in a register when the position of the motor rotor is determined, so as to control the motor based on the position signal in the register.

7. The device according to claim 1, characterized in that The control module is also used to perform open-loop control on the motor using a constant voltage-frequency ratio or a constant current-frequency ratio.

8. A chip, characterized in that: It comprises the motor rotor position acquisition device according to any one of claims 1-7.

9. A motor controller, characterized in that: It comprises the motor rotor position acquisition device according to any one of claims 1-7.

10. An electrical device, characterized in that: It comprises the motor rotor position acquisition device according to any one of claims 1 to 7, or the chip according to claim 8, or the motor controller according to claim 9.

11. A method for obtaining a motor rotor position, characterized in that: Applied to a motor controller, the motor controller includes a multi-phase bridge arm, the multi-phase bridge arm includes an upper bridge arm and a lower bridge arm respectively, the upper bridge arm includes an upper bridge arm switch tube connected in parallel with a freewheeling diode, the lower bridge arm includes a lower bridge arm switch tube connected in parallel with a freewheeling diode, and the method includes: Acquire a level signal corresponding to a dead zone voltage of a target bridge arm within a dead zone time, wherein, within the dead zone time, an upper bridge arm switch tube and a lower bridge arm switch tube of the target bridge arm are respectively disconnected, and a voltage generated on the target bridge arm by the current flowing through the freewheeling diode is the dead zone voltage; Based on the level signal, the motor rotor position is determined.

12. A computer-readable storage medium, characterized in that: A program is stored thereon, and when the program is executed by a processor, the method for obtaining the motor rotor position according to claim 11 is implemented.

Images