Synchronous motor torque ripple suppression control device and control method thereof
By adopting a mixed injection control method of compensation current and compensation voltage in a synchronous motor, the problem of poor torque pulsation suppression effect at high and low speeds is solved, and the effect of effectively suppressing torque pulsation at any speed is achieved.
Patent Information
- Application Number
- CN202510107092.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-06-17
AI Technical Summary
The prior art has the effect of torque pulsation suppression deteriorates when the motor is at a high speed, or the effect deteriorates when the motor is at a low speed, so it is impossible to maintain a good torque pulsation suppression effect at both high and low speeds.
The mixed injection control method of compensation current and compensation voltage is adopted. The compensation current data table, proportional setting unit and voltage conversion unit are used to adjust the magnitude of compensation current and compensation voltage to ensure that the torque pulsation can be effectively suppressed at low or high speed of the motor.
It realizes that the torque pulsation suppression effect can be maintained at both low speed and high speed of the motor, avoiding the problem of deterioration of the effect at high speed or deterioration of the effect at low speed.
Smart Images
Figure CN120165614A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a synchronous motor, and in particular to a synchronous motor torque ripple suppression control device and a control method for torque control of a synchronous motor. Background Art
[0002] A synchronous motor is the heart of electromechanical products, a device for realizing the conversion between electrical energy and mechanical energy, and generates torque through the interaction between the rotating magnetic field generated by the stator coil and the rotor permanent magnet magnetic field. If there is a torque ripple component during the operation of the synchronous motor, it will cause resonance and noise generation of the components connected to the motor, or reduce the position accuracy and speed accuracy of the servo motor, or damage other components; the representative reasons for generating torque ripple include the existence of harmonic components of the magnetic flux of the motor rotor magnet. Figure 9 is the harmonic order of the typical magnet magnetic flux that generates torque ripple.
[0003] The existing technical principle for realizing motor torque ripple suppression through motor control technology is as follows: such as Figure 10 、 Figure 11 , for an interior permanent magnet motor (IPM), its torque and torque ripple in the dq rotating coordinate can be expressed as: Where, represents the part that generates torque ripple; if a compensation current is injected into the q-axis current , and a compensation current is injected into the d-axis current : Then formula 10 can be rewritten as: Where, is the torque, and ( are the torque ripple parts, and have small values and can be ignored.
[0004] By injecting the compensation current and the compensation current , the torque ripple part becomes 0, and the original torque ripple is cancelled out. After cancellation, it is obtained as Figure 11The ideal torque shown above. The method for suppressing torque ripple based on motor control technology compensates the current and can adopt the feedforward control method - that is, the data table method (see Figure 7 ), or the negative feedback control method for compensating the current of the synchronous motor torque ripple and (see Figure 8 ) to achieve.
[0005] For the control device and method of a permanent magnet synchronous motor with Japanese Patent Publication No. 2002 - 223582, the existing problem is that the current controller generally adopts a PI (Proportional Integral) controller, and the PI controller can only control DC or low - frequency signals. Therefore, this form of current compensation will deteriorate the torque ripple suppression effect at high motor speeds. For the motor control device with Japanese Patent Publication No. 7218700, the existing problem is that the compensation voltage will correspondingly generate a compensation current with the same frequency. At low frequencies, after this current passes through the PI controller, a voltage will be generated, and this voltage will be superimposed on the compensation voltage, changing the compensation voltage. Therefore, this form of compensation voltage will deteriorate the torque ripple suppression effect at low motor speeds. Summary of the Invention
[0006] By solving the problem that the torque ripple suppression effect deteriorates at high motor speeds or at low motor speeds, that is, the problem that good torque ripple suppression effects cannot be maintained at both high and low motor speeds, the present invention provides a new control method for suppressing the torque ripple of a synchronous motor, that is, a control device and its control method for suppressing the torque ripple of a synchronous motor that can maintain good torque ripple suppression effects at both low and high motor speeds.
[0007] The specific technical solution adopted by the present invention to solve the above - mentioned technical problems is as follows: A control device for suppressing the torque ripple of a synchronous motor, which comprises a speed controller, a current controller, a current command conversion unit, a dq / uvw conversion unit, an inverter, a uvw / dq conversion unit, a motor, a speed sensor, and a position - speed calculation unit. Before the current command conversion unit is the speed controller, and after the current command conversion unit, a dq - axis current controller, a dq / uvw conversion unit, and an inverter are arranged in sequence. The inverter receives the input of the dq / uvw conversion unit and outputs the voltage and current required by the motor. The uvw / dq conversion unit converts the sampled current flowing into the motor into the q - axis and d - axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller. The speed sensor obtains the mechanical rotation angle of the motor and outputs it to the position - speed calculation unit, and the position - speed calculation unit calculates the electrical rotation angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit, and outputs the electrical speed A speed controller, characterized in that it further includes a compensation current data table, a proportional setting unit, and a voltage conversion unit. The compensation current data table, the proportional setting unit, and the voltage conversion unit are used to provide a hybrid injection control of compensation current and compensation voltage for suppressing the torque ripple of a synchronous motor. The compensation current and (where n is the number corresponding to the torque ripple to be suppressed, for example, n = 6) are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit, and after the two are combined, they are respectively used as the current command of the q-axis current controller and the current command of the d-axis current controller. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input terminals of the dq / uvw conversion unit and are respectively combined with the d-axis output voltage and the q-axis output voltage of the d-axis and q-axis current controllers. The electrical speed output by the position and speed calculation unit is respectively input to the compensation current data table, the proportional setting unit, and the voltage conversion unit. Through the hybrid injection method of compensation current and compensation voltage, a compensation current for eliminating a certain component of torque ripple is set for a given motor load. When the motor rotates at low speed or high speed, the actual compensation current in the motor current can be made unchanged, so that torque ripple suppression can be achieved at any speed of the motor.
[0008] The proportional setting unit is placed immediately after the compensation current data table. The proportional setting unit performs proportional conversion on the q-axis compensation current and the d-axis compensation current and then inputs them to the voltage conversion unit. At the same time, they are respectively input to the q-axis current command and the d-axis current command output by the current command conversion unit. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input to the corresponding input terminals of the dq / uvw conversion unit. The electrical speed of the position and speed calculation unit is respectively input to the compensation current data table, the proportional setting unit, and the voltage conversion unit. By adopting the hybrid injection method of compensation current and compensation voltage, a compensation current for eliminating a certain component of torque ripple is set for a given motor load. The proportional setting unit adjusts the magnitude of the compensation current according to the speed, so that the actual compensation current in the motor current can be made unchanged, so that torque ripple suppression can be achieved at any speed of the motor.
[0009] The compensation current of the compensation current data table and the compensation current are directly input into the q-axis current command output by the current command conversion unit without passing through the ratio setting unit and the d-axis current command simultaneously, and the compensation current in the compensation current data table and the compensation current are input into the ratio setting unit. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input into the corresponding input terminals of the dq / uvw conversion unit. The electrical rotational speed of the position and speed calculation unit is respectively input into the compensation current data table, the ratio setting unit, and the voltage conversion unit. The ratio setting unit is placed after the compensation current data table. The ratio setting unit adjusts the magnitude of the compensation current according to the magnitude of the speed, so that when the load remains unchanged and only the speed changes, the actually existing compensation current in the motor current remains unchanged.
[0010] The compensation current in the compensation current data table and the compensation current are directly injected into the voltage conversion unit. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input terminals of the dq / uvw conversion unit. At the same time, the compensation current in the compensation current data table and the compensation current after passing through ratio conversion are injected into the q-axis current command output by the current command conversion unit and the d-axis current command , and the electrical rotational speed of the position and speed calculation unit is respectively input into the compensation current data table, the ratio setting unit, and the voltage conversion unit. The ratio setting unit is placed before the compensation current superposition. The ratio setting unit adjusts the magnitude of the compensation current according to the magnitude of the speed, so that when the load remains unchanged and only the speed changes, the actually existing compensation current in the motor current remains unchanged.
[0011] Multiple groups of the compensation current data table, the ratio setting unit, and the voltage conversion unit are provided to achieve suppression of multiple components of torque ripple. The compensation current in the compensation current data table in each group and the compensation current are respectively injected into the q-axis current command output by the current command conversion unit in any one of the above technical solutions and the d-axis current command , and at the same time, the d-axis compensation voltage and the q-axis compensation voltage in each group are respectively input into the corresponding input terminals of the dq / uvw conversion unit, where k is a natural number 1, 2, ……, and the electrical rotational speed of the position and speed calculation unit The compensation current data table, the ratio setting unit, and the voltage conversion unit are respectively input. By injecting a mixture of multiple groups of compensation currents and compensation voltages, the effectiveness of suppressing multiple torque ripples is improved.
[0012] One or more groups of the compensation current data table, the ratio setting unit, and the voltage conversion unit are provided, and the compensation current in the compensation current data table and the compensation current are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit in the manner of any of the above technical solutions. At the same time, the d-axis compensation voltage and the q-axis compensation voltage are respectively injected into the corresponding input ends of the dq / uvw conversion unit; in a sensorless manner, the d-axis voltage and the q-axis voltage of the controller and the q-axis current and the d-axis current converted by the uvw / dq conversion unit are output to the position and speed calculation unit to calculate the electrical speed and the electrical angle ; the motor speed of the position and speed calculation unit is respectively input to the compensation current data table, the ratio setting unit, and the voltage conversion unit. In sensorless control, the speed signal is obtained by the position and speed calculation unit, and the principle of torque ripple suppression remains unchanged. Without setting the ratio setting unit and the voltage conversion unit, the compensation current and the compensation current generated by the compensation current generation unit in the compensation current data table are directly input to the q-axis current command and the d-axis current command output by the current command conversion unit respectively. The d-axis output voltage and the q-axis output voltage of the d-axis and q-axis current controllers are feedback input to the compensation current generation unit and input to the position and speed calculation unit at the same time; the uvw / dq conversion unit converts the sampled current flowing into the motor into the q-axis and d-axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller, and at the same time, inputs them to the compensation current generation unit and the position and speed calculation unit respectively. The position and speed calculation unit calculates the electrical angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit, and at the same time, outputs the electrical angle .
[0013] In the above-mentioned compensation current injection situation, for the IPM motor, the q-axis compensation current and the d-axis compensation current ; For surface-mounted permanent magnet motors, since there is only flux torque and flux torque ripple, and no reluctance torque ( ), and the d-axis current command = 0; Therefore, only the q-axis compensation current needs to be injected.
[0014] Another object of the present invention is to provide a method for suppressing torque ripple of a synchronous motor, which is characterized in that: the torque ripple suppression control device described in one of the above technical solutions is adopted, and the following torque ripple suppression control means are adopted: A1. By introducing a compensation current data table, a proportional setting unit, and a voltage conversion unit, a hybrid injection method of compensation current and compensation voltage is adopted, and the compensation current actually flowing into the motor remains unchanged when only the speed changes while the load remains unchanged, so as to achieve torque ripple suppression in the full speed and full load range; A2. The proportional setting unit adjusts the magnitude of the compensation current output by the compensation current data table according to the magnitude of the speed, so that the compensation current actually flowing into the motor remains unchanged when only the speed changes while the load remains unchanged; A3. For the phenomenon that there are multiple components of torque ripple in the synchronous motor, a hybrid injection method of multiple groups of compensation current and compensation voltage is adopted to achieve the suppression control of multiple torque ripple components; A4. When there is no speed sensor control, the speed signal is obtained by speculation of the position speed calculation unit, and the principle of the torque ripple suppression means remains unchanged; A5. In the above steps A1 to A5, at a certain load, let the synchronous motor rotate at a certain high speed, for example, 500 rpm, and according to the compensation current of the compensation current data table, the proportional setting unit, and the formula of the voltage equation, measure the amplitude and phase of the compensation current required to suppress the torque ripple component to be suppressed, and use it as the target compensation current, and execute the following steps A6 to A9 or steps A10 to A14; A6. The compensation current and the compensation voltage are implemented simultaneously, and the motor speed is changed to obtain the actual q-axis compensation current and d-axis compensation current; A7. According to the compensation current of the compensation current data table, the proportional setting unit, and the formula of the voltage equation, calculate the multiple relationship between the actual q-axis compensation current, d-axis compensation current, and the target compensation current, and find the approximate function of the reciprocal of the multiple relationship; A8. Change the load and repeat the above steps A5 to A7 to obtain the compensation current data table; A9. Implement torque ripple suppression in which the compensation current and the compensation voltage are both effective; A10. The compensation current and the compensation voltage are both effective, and the motor speed is changed from high speed to low speed; A11. Calculate the actual q-axis compensation current and d-axis compensation current according to the compensation current in the compensation current data table, the proportional setting unit, and the formula of the voltage equation. If they are inconsistent with the target compensation current, adjust the proportional coefficient. When they are consistent, record the proportional coefficient; A12. Find the approximate function of the proportional coefficient in step A11, or save the proportional coefficient in step A11 as a data table; A13. Change the load, repeat the above steps A5 and A11 - A12 to obtain the compensation current data table; A14. Implement torque ripple suppression with both the compensation current and the compensation voltage being effective.
[0015] Adopting the hybrid compensation method of current and voltage can achieve good effects both at low and high speeds of the synchronous motor.
[0016] The beneficial effects of the present invention are as follows: It can not only effectively suppress the torque ripple of the synchronous motor, but also avoid the deterioration of the effect at high motor speeds or low motor speeds, and maintain good effects both at low and high speeds of the motor. Description of the Drawings
[0017] The following further elaborates on the present invention in detail in conjunction with the drawings and specific embodiments.
[0018] Figure 1 It is a schematic structural block diagram of Embodiment 1 of the torque ripple suppression control device and its control method for a synchronous motor of the present invention based on the hybrid injection control of compensation current and compensation voltage.
[0019] Figure 2 It is a schematic structural block diagram of Embodiment 2 of the torque ripple suppression control device and its control method for a synchronous motor of the present invention based on the hybrid injection control of compensation current and compensation voltage.
[0020] Figure 3 It is a schematic structural block diagram of Embodiment 3 of the torque ripple suppression control device and its control method for a synchronous motor of the present invention based on the hybrid injection control of compensation current and compensation voltage.
[0021] Figure 4 It is a schematic structural block diagram of Embodiment 4 of the torque ripple suppression control device and its control method for a synchronous motor of the present invention based on the hybrid injection control of compensation current and compensation voltage.
[0022] Figure 5 It is a schematic structural block diagram of Embodiment 5 of the torque ripple suppression control device and its control method for a synchronous motor of the present invention based on the hybrid injection control of compensation current and compensation voltage.
[0023] Figure 6It is a schematic structural diagram of Embodiment 6 of the synchronous motor torque ripple suppression control device and its control method of the present invention based on hybrid injection control of compensation current and compensation voltage.
[0024] Figure 7 It is the compensation principle block diagram of the feedforward control method - data table method for compensating the torque ripple of the synchronous motor in the prior art for compensating current.
[0025] Figure 8 It is the compensation principle block diagram of the negative feedback control method for compensating the torque ripple of the synchronous motor in the prior art for compensating current.
[0026] Figure 9 It is a schematic diagram of the typical harmonic orders of the torque ripple generated by the magnetic flux harmonics of the motor rotor magnet in the torque ripple of the synchronous motor in the prior art. Figure 10 It is a schematic diagram of the torque ripple compensation principle of the method for suppressing torque ripple by using motor control technology for the torque ripple of the synchronous motor in the prior art.
[0027] Figure 11 It is by using Figure 10 compensation technology method to inject compensation current and the schematic diagram of the ideal compensation effect of the torque ripple obtained. Specific implementation manner
[0028] Embodiment 1 Figure 1 In the shown embodiment, a torque ripple suppression control device for an interior permanent magnet synchronous motor (IPM) includes a speed controller, a current controller, a current command conversion unit, a dq / uvw conversion unit, an inverter, a uvw / dq conversion unit, a motor, a speed sensor, and a position and speed calculation unit. Before the current command conversion unit is the speed controller. After the current command conversion unit, a dq-axis current controller, a dq / uvw conversion unit, and an inverter are sequentially arranged. The inverter receives the input of the dq / uvw conversion unit and outputs the voltage and current required by the motor. The uvw / dq conversion unit converts the sampled current flowing into the motor into the q-axis and d-axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller. The speed sensor obtains the mechanical rotation angle of the motor and outputs it to the position and speed calculation unit. The position and speed calculation unit calculates the electrical rotation angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit, and outputs the electrical rotational speed to the speed controller. It also includes a compensation current data table, a proportional setting unit, and a voltage conversion unit. The compensation current data table, the proportional setting unit, and the voltage conversion unit are used to provide hybrid injection control of compensation current and compensation voltage for suppressing the torque ripple of the synchronous motor. The compensation current and are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit. After the two are combined, they are respectively used as the current commands of the q-axis current controller and the d-axis current controller. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input terminals of the dq / uvw conversion unit and are respectively combined with the d-axis output voltage and the q-axis output voltage of the d-axis and q-axis current controllers. The electrical rotational speed output by the position and speed calculation unit is respectively input to the compensation current data table, the proportional setting unit, and the voltage conversion unit. The proportional setting unit is placed immediately after the compensation current data table. The proportional setting unit performs proportional conversion on the q-axis compensation current and the d-axis compensation current and then inputs them to the voltage conversion unit. At the same time, they are respectively input to the q-axis current command output by the current command conversion unit and the current command of the d-axis current controller. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input to the corresponding input terminals of the dq / uvw conversion unit. The electrical rotational speed of the position and speed calculation unit is respectively input to the compensation current data table, the proportional setting unit, and the voltage conversion unit.
[0029] First, the compensation current will be described. The compensation current and in the compensation current data table are expressed as: Where: and are the amplitudes, h represents the harmonic, n is the order, is the electrical rotational speed, and are the phases.
[0030] The compensation current and can be obtained by two methods. The first method is theoretical calculation, and the second method is as described in Embodiment 7. For the first method, for example, for the suppression of the 6th torque ripple, the torque formula of the IPM motor can be expressed as follows: Wherein: is the magnet torque, is the reluctance torque; is the flux torque ripple ①; is the injected torque ripple ②; is the injected torque ripple ③; : the number of rotor magnetic poles, and : the q-axis fundamental current and d-axis fundamental current that generate torque, : the fundamental component of the rotor magnet flux, : the amplitude of the 6th harmonic component of the rotor magnet flux, : the phase of the 6th harmonic component of the rotor magnet flux, and : the phases of the 6th harmonic components of the q-axis compensation current and d-axis compensation current. The flux torque ripple ① in Formula 2 is caused by the harmonic components of the magnet flux, and the injected torque ripples ② and ③ are generated by the compensation current generates, and the injected torque ripple ④ is generated by the compensation current generates. By making the sum of the flux torque ripple ① and the injected torque ripple ② equal to 0, the compensation current is as follows: Then, by making the sum of the injected torque ripples ③ and ④ equal to 0, the compensation current is as follows: However, this method requires prior knowledge of the amplitude and phase of the harmonic components of the magnet flux.
[0031] Secondly, the formula adopted by the ratio setting unit is: Wherein: , , are binomial coefficients, , , are binomial coefficients, and K is a proportionality coefficient.
[0032] The speed ω1 represents a low speed, such as 50 rpm. Below this speed, the current compensation at the input of the current controller injecting into the q-axis current and d-axis current plays a major role in suppressing torque ripple; the speed represents a high speed, such as 300 rpm. Above this speed, the compensation voltage and plays a major role in suppressing torque ripple; between the speeds and simultaneously, current compensation at the input of the current controller and voltage compensation at the input of the dq / uvw conversion section are in effect, so a polynomial with coefficients , , is required to give a proportionality factor less than 1.
[0033] Secondly, the voltage conversion section is described. The voltage equation of the motor can be expressed as: During steady-state operation, if by applying compensation voltages and , a compensation current and are generated on the q-axis, then the voltage equation formula of the IPM motor is written as: + From this, we can obtain: Where: is the d-axis voltage; is the q-axis voltage; is the d-axis compensation voltage; is the q-axis compensation voltage; R is the single-phase resistance of the motor; is the base value of the magnet flux; is the d-axis current; is the q-axis current; is the electrical speed of the motor; is the d-axis inductance; is the q-axis inductance.
[0034] Figure 1 For the implementation example of , the control part other than the motor, inverter, and speed sensor can be implemented in a digital processor (such as an MCU microcontroller) or in the form of a circuit.
[0035] The above description is for the interior permanent magnet synchronous motor (IPM motor). For the surface permanent magnet motor (SPM), since there is only flux torque and flux torque ripple, and no reluctance torque ( ), and the d-axis current command = 0. Therefore, for the torque formula (3), only the compensation current , the suppression of the torque ripple of the SPM motor can be achieved by making the sum of the flux torque ripple ① and the injected torque ripple ② equal to 0. That is, for Figure 1 , remove the compensation current from the injection of the d-axis current command output by the current command conversion unit, and at the same time make the compensation current in formula (5) equal to 0.
[0036] Embodiment 2 Figure 2 In the embodiment shown, the compensation current and the compensation current in the compensation current data table are directly input into the q-axis current command and the d-axis current command output by the current command conversion unit respectively without passing through the proportional setting unit. At the same time, the compensation current and the compensation current in the compensation current data table are input into the proportional setting unit, and the voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input terminals of the dq / uvw conversion unit. The electrical speed of the position and speed calculation unit is respectively input into the compensation current data table, the proportional setting unit and the voltage conversion unit. The others are the same as those in Embodiment 1.
[0037] Embodiment 3 Figure 3 In the embodiment shown, the compensation current and the compensation current in the compensation current data table are directly input into the voltage conversion unit, and the voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input into the corresponding input terminals of the dq / uvw conversion unit. At the same time, the compensation current and the compensation current in the compensation current data table are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit after proportional conversion. The electrical speed of the position and speed calculation unit is respectively input into the compensation current data table, the proportional setting unit and the voltage conversion unit. The others are the same as those in Embodiment 1.
[0038] Embodiment 4 Figure 4 In the embodiment shown, multiple sets of compensation current data tables, proportional setting units and voltage conversion units are provided to achieve the suppression of multiple components of the torque ripple. In each set, the compensation current and the compensation current Inject into the q-axis current command output by the current command conversion unit in any of the above-described embodiments and the d-axis current command , and at the same time input the d-axis compensation voltage and the q-axis compensation voltage into the corresponding input terminals of the dq / uvw conversion unit respectively, where k is a natural number among 1, 2, ……, and the electrical rotational speed of the position speed calculation unit is input into the compensation current data table, the ratio setting unit, and the voltage conversion unit respectively. The rest is the same as that of Embodiment 1.
[0039] Embodiment 5: Figure 5 In the embodiment shown, one or more groups of the compensation current data table, the ratio setting unit, and the voltage conversion unit are provided, and the compensation current and the compensation current in the compensation current data table are injected into the q-axis current command and the d-axis current command output by the current command conversion unit in any of the above embodiments respectively, and at the same time inject the d-axis compensation voltage and the q-axis compensation voltage into the corresponding input terminals of the dq / uvw conversion unit respectively; the d-axis voltage , q-axis voltage of the controller, the q-axis current and d-axis current converted by the uvw / dq conversion unit are output to the position speed calculation unit to calculate the electrical rotational speed and the electrical rotation angle ; the motor rotational speed of the position speed calculation unit is input into the compensation current data table, the ratio setting unit, and the voltage conversion unit respectively. The rest is the same as that of Embodiment 1.
[0040] Embodiment 6: Figure 6 In the embodiment shown, the ratio setting unit and the voltage conversion unit are not provided, and the compensation current and the compensation current generated by the compensation current generation unit of the compensation current data table are directly input into the q-axis current command and the d-axis current command output by the current command conversion unit respectively, and the d-axis output voltage and the q-axis output voltage The feedback is input to the compensation current generation unit and simultaneously input to the position and speed calculation unit; while the uvw / dq conversion unit converts the sampled current flowing into the motor into the q-axis and d-axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller, it is respectively input to the compensation current generation unit and the position and speed calculation unit, and the position and speed calculation unit calculates the electrical rotation angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit, and simultaneously outputs the electrical rotation angle . Others are the same as those in Embodiment 1.
[0041] Embodiment 7 Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 In the embodiments shown in Figure 3 , Figure 4 , Figure 5 , Figure 6 , a synchronous motor torque ripple suppression control method adopts the synchronous motor torque ripple suppression control device described in one of the above embodiments, and adopts the following torque ripple suppression control means A1. By introducing a compensation current data table, a proportional setting unit and a voltage conversion unit, adopting a hybrid injection method of compensation current and compensation voltage, and making the compensation current actually flowing into the motor unchanged when only the speed changes while the load remains unchanged, to achieve torque ripple suppression in the full speed and full load range; A2. The proportional setting unit adjusts the magnitude of the compensation current output by the compensation current data table according to the magnitude of the speed, so that the compensation current actually flowing into the motor remains unchanged when only the speed changes while the load remains unchanged; A3. For the phenomenon that there are multiple components in the synchronous motor torque ripple, adopt a hybrid injection method of multiple groups of compensation current and compensation voltage to achieve the suppression control of multiple torque ripple components; A4. When there is no speed sensor control, the speed signal is obtained by estimation by the position and speed calculation unit, and the principle of the torque ripple suppression means remains unchanged; A5. In the above steps A1 to A5, at a certain load, let the synchronous motor rotate at a certain high speed, for example, 500 rpm. According to the compensation current of the compensation current data table, the proportional setting unit and the formula of the voltage equation, measure the amplitude and phase of the compensation current required to suppress the torque ripple component to be suppressed, and use it as the target compensation current, and execute the following steps A6 to A9 or steps A10 to A14; A6. The compensation current and the compensation voltage are implemented simultaneously, and the motor speed is changed to obtain the actual q-axis compensation current and d-axis compensation current; A7. According to the compensation current of the compensation current data table, the proportional setting unit and the formula of the voltage equation, calculate the multiple relationship between the actual q-axis compensation current and d-axis compensation current and the target compensation current, and find the approximate function of the reciprocal of the multiple relationship; A8. Change the load and repeat the above steps A5 to A7 to obtain a compensation current data table; A9. Implement torque ripple suppression with both the compensation current and the compensation voltage being effective; A10. With both the compensation current and the compensation voltage being effective, change the motor speed from high speed to low speed; A11. Calculate the actual q-axis compensation current and d-axis compensation current according to the compensation current in the compensation current data table, the ratio setting unit, and the formulas of the voltage equation. If they are inconsistent with the target compensation current, adjust the proportionality coefficient. When they are consistent, record the proportionality coefficient; A12. Find the approximate function of the proportionality coefficient in step A11, or save the proportionality coefficient in step A11 as a data table; A13. Change the load and repeat the above steps A5 and A11 to A12 to obtain a compensation current data table; A14. Implement torque ripple suppression with both the compensation current and the compensation voltage being effective.
[0042] The others are the same as in Embodiment 1, Embodiment 2, Embodiment 3, Embodiment 4, Embodiment 5, or Embodiment 6.
[0043] Embodiment 8 Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 In the embodiments shown, the following specific implementation steps are obtained from experiments for the above embodiments: Step 1: Disconnect Figure 1 the injection of the compensation current from the output of the ratio setting unit to the q-axis current command and d-axis current command outputs of the current conversion unit, and set the output of the ratio setting unit to 1, that is, only make the voltage compensation alone effective; the calculation of the voltage conversion unit is as shown in the above formulas 9a and 9b. For a given load, let the motor rotate at a certain high speed, for example, 500 rpm. Debug the amplitude and phase in formula 1 and the amplitude and phase , and at the same time test the torque ripple component of the motor. When the torque ripple component to be suppressed is reduced to the target value, the amplitude and phase and and phase at this time are the amplitude and phase of the required compensation current, and take them as the target compensation current.
[0044] Step 2: Connect Figure 1Inject the compensation current from the output of the proportional setting unit to the q-axis current command and d-axis current command outputs of the current conversion unit, and set the output of the proportional setting unit to 1, even if the compensation current and voltage compensation are both effective; the calculation of the voltage conversion unit is as shown in the above formulas 9a and 9b. Use the compensation current obtained in Step 1 and , but change the motor speed, for example, sequentially rotate the motor at speeds of 10 rpm, 50 rpm, 80 rpm, 120 rpm, and 160 rpm, and record the amplitudes of the harmonic currents in the actual q-axis current Iq and d-axis current Id at each speed, such as the amplitudes of the 6th-order q-axis harmonic current and d-axis harmonic current.
[0045] Step 3: Divide the amplitudes of the harmonic currents in the actual q-axis current Iq and d-axis harmonic current Id obtained in Step 2 by the amplitude of the target compensation current obtained in Step 1 to obtain the multiple relationships between the amplitudes of the actual q-axis harmonic current and the target harmonic current, and between the amplitudes of the actual d-axis harmonic current and the target harmonic current.
[0046] Step 4: Calculate the reciprocals of the multiple relationships obtained in Step 3 and fit the approximate function of this reciprocal. For example, the piecewise binomial function shown in the above formula 6 can be used as the approximate function and its coefficients can be fitted. This approximate function is the Figure 1 formula required for the calculation between the input and output of the proportional setting unit.
[0047] Step 5: For the case of variable load, change the load and repeat Steps 1 to 4. For each load, record the amplitude and phase of the target compensation current obtained in Step 1 as the Figure 1 data in the compensation current data table; at the same time, record the approximate function obtained in Step 4 for calculating the calculation between the input and output at each load.
[0048] Step 6: Apply the compensation current data table and approximate function obtained in Step 5 to implement the control technology for suppressing torque ripple with both the actual compensation current and compensation voltage being effective.
[0049] The above-mentioned second method is only an example and is not limited to this method. For other methods, for example, in the second step, instead of setting the ratio setting unit to 1, the above formula 6 is directly used; the motor speed is changed (for example: the speed is successively set to 500 rpm, 450 rpm, 400 rpm, 350 rpm,...), and the amplitudes of the harmonic currents of the actual q-axis current Iq and d-axis current Id are measured. If they are inconsistent with the amplitude of the target compensation current obtained in the first step, the coefficients of formula 6 are adjusted until the amplitudes of the actual q-axis harmonic current and d-axis harmonic current are respectively consistent with the amplitude of the target compensation current. At this time, the proportional coefficient of the above formula 6 obtained is recorded.
[0050] The above two methods are described with IPM motors as the object. For surface-mounted permanent magnet motors (SPM), only the compensation current needs to be considered. That's all.
[0051] The rest is the same as in Embodiment 1, Embodiment 2, Embodiment 3, Embodiment 4, Embodiment 5, Embodiment 6, or Embodiment 7.
[0052] The above content and structure describe the basic principles, main features, and advantages of the product of the present invention, which should be understood by those skilled in the art. The above examples and descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.
Claims
1. A synchronous motor torque ripple suppression control device, which comprises a speed controller, a current controller, a current command conversion unit, a dq / uvw conversion unit, an inverter, a uvw / dq conversion unit, a motor, a speed sensor, and a position and speed calculation unit. Before the current command conversion unit is the speed controller. After the current command conversion unit, a dq-axis current controller, a dq / uvw conversion unit, and an inverter are sequentially provided. The inverter receives the input of the dq / uvw conversion unit and outputs the voltage and current required by the motor. The uvw / dq conversion unit converts the sampled current flowing into the motor into the q-axis and d-axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller. The speed sensor obtains the mechanical rotation angle of the motor and outputs it to the position and speed calculation unit, and the position and speed calculation unit calculates the electrical rotation angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit, and outputs the electrical speed to the speed controller. Its characteristics are as follows It further includes a compensation current data table, a ratio setting unit, and a voltage conversion unit. The compensation current data table, the ratio setting unit, and the voltage conversion unit are used to provide hybrid injection control of compensation current and compensation voltage for suppressing the torque ripple of the synchronous motor. The compensation current and are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit. After the two are combined, they are respectively used as the current commands of the q-axis current controller and the d-axis current controller. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input ends of the dq / uvw conversion unit and are respectively combined with the d-axis output voltage and the q-axis output voltage of the d-axis and q-axis current controllers. The electrical speed output by the position and speed calculation unit is respectively input into the compensation current data table, the ratio setting unit, and the voltage conversion unit.
2. The synchronous motor torque ripple suppression control device according to claim 1, characterized in that The proportional setting unit is placed immediately after the compensation current data table. The proportional setting unit performs proportional conversion on the q-axis compensation current and the d-axis compensation current respectively, and then inputs them into the voltage conversion unit. At the same time, they are respectively input into the q-axis current command and the d-axis current command output by the current command conversion unit. The voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input into the corresponding input terminals of the dq / uvw conversion unit. The electrical rotational speed of the position and speed calculation unit is respectively input into the compensation current data table, the proportional setting unit, and the voltage conversion unit.
3. The synchronous motor torque ripple suppression control device according to claim 1, characterized in that The compensation current in the compensation current data table and the compensation current are directly input into the q-axis current command and the d-axis current command output by the current command conversion unit without passing through the ratio setting unit. At the same time, the compensation current in the compensation current data table and the compensation current are input into the ratio setting unit, and the voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively input into the corresponding input terminals of the dq / uvw conversion unit. The electrical rotational speed of the position speed calculation unit is respectively input into the compensation current data table, the ratio setting unit and the voltage conversion unit.
4. The synchronous motor torque ripple suppression control device according to claim 1, characterized in that The compensation current in the compensation current data table and the compensation current are directly injected into the voltage conversion unit, and the voltage conversion unit outputs the d-axis compensation voltage and the q-axis compensation voltage which are respectively injected into the corresponding input terminals of the dq / uvw conversion unit. At the same time, the compensation current in the compensation current data table and the compensation current after proportional conversion are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit. The electrical rotational speed of the position and speed calculation unit is respectively injected into the compensation current data table, the proportional setting unit and the voltage conversion unit.
5. The synchronous motor torque ripple suppression control device according to claim 1, characterized in that The compensation current data table, the ratio setting unit, and the voltage conversion unit are provided in multiple sets to suppress multiple components of torque ripple. The compensation current in the compensation current data table in each set and the compensation current are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit. At the same time, the d-axis compensation voltage and the q-axis compensation voltage in each set are respectively input to the corresponding input terminals of the dq / uvw conversion unit, where k is a natural number 1, 2, ……, and the electrical rotational speed of the position speed calculation unit is respectively input to the compensation current data table, the ratio setting unit, and the voltage conversion unit.
6. The synchronous motor torque ripple suppression control device according to claim 5, characterized in that The compensation current data table, the ratio setting unit, and the voltage conversion unit are provided in one or more sets, and the compensation current in the compensation current data table and the compensation current are respectively injected into the q-axis current command and the d-axis current command output by the current command conversion unit in any one of the manners of claims 2 to 5. At the same time, the d-axis compensation voltage and the q-axis compensation voltage are respectively injected into the corresponding input ends of the dq / uvw conversion unit; the d-axis voltage , the q-axis voltage of the controller, and the q-axis current and the d-axis current converted by the uvw / dq conversion unit are output to the position and speed calculation unit to calculate the electrical speed and the electrical rotation angle ; the motor speed of the position and speed calculation unit is respectively input into the compensation current data table, the ratio setting unit, and the voltage conversion unit.
7. The synchronous motor torque ripple suppression control device according to claim 1, characterized in that Without setting a ratio setting unit and a voltage conversion unit, the compensation current generated by the compensation current generation unit of the compensation current data table and the compensation current are directly input into the q-axis current command and the d-axis current command output by the current command conversion unit respectively. The d-axis output voltage and the q-axis output voltage of the d-axis and q-axis current controllers are feedback input to the compensation current generation unit and input to the position and speed calculation unit at the same time. The uvw / dq conversion unit converts the sampled current flowing into the motor into the q-axis and d-axis currents in the dq rotating coordinate system and inputs them to the input end of the current controller. At the same time, they are respectively input to the compensation current generation unit and the position and speed calculation unit. The position and speed calculation unit calculates the electrical rotation angle and outputs it to the dq / uvw conversion unit and the uvw / dq conversion unit. At the same time, the electrical rotation angle .
8. The synchronous motor torque ripple suppression control device according to any one of claims 1 to 7, characterized in that In each of the above compensation current injection cases, a q-axis compensation current is injected and a d-axis compensation current are applicable to surface-mounted permanent magnet synchronous motors; for interior permanent magnet motors, since there are only flux torque and flux torque ripple, and there is no reluctance torque( ), and the d-axis current command = 0; therefore, in each of the above compensation current injection cases, only a q-axis compensation current needs to be injected.
9. A synchronous motor torque ripple suppression control method, characterized in that The synchronous motor torque ripple suppression control device described in any one of claims 1 to 8 is adopted, and the following torque ripple suppression control means are adopted: A1. By introducing a compensation current data table, a proportional setting unit, and a voltage conversion unit, adopting a hybrid injection method of compensation current and compensation voltage, and keeping the actual compensation current flowing into the motor unchanged when only the speed changes while the load remains unchanged, to achieve torque ripple suppression in the full speed and full load range; A2. The proportional setting unit adjusts the magnitude of the compensation current output by the compensation current data table according to the magnitude of the speed, so that the actual compensation current flowing into the motor remains unchanged when only the speed changes while the load remains unchanged; A3. For the phenomenon that there are multiple components in the synchronous motor torque ripple, a hybrid injection method of multiple sets of compensation current and compensation voltage is adopted to achieve the suppression control of multiple torque ripple components; A4. When there is no speed sensor control, the speed signal is obtained by position-speed calculation and speculation, and the principle of the torque ripple suppression means remains unchanged; A5. In the above steps A1 to A5, at a certain load, let the synchronous motor rotate at a certain high speed, such as 500 rpm, and according to the compensation current in the compensation current data table, the proportional setting unit, and the formula of the voltage equation, measure the amplitude and phase of the compensation current required to suppress the torque ripple component to be suppressed, and use it as the target compensation current, and execute the following steps A6 to A9 or steps A10 to A14; A6. The compensation current and the compensation voltage are implemented simultaneously, and the motor speed is changed to obtain the actual q-axis compensation current and d-axis compensation current; A7. According to the compensation current in the compensation current data table, the proportional setting unit, and the formula of the voltage equation, calculate the multiple relationship between the actual q-axis compensation current and d-axis compensation current and the target compensation current, and find the approximate function of the reciprocal of the multiple relationship; A8. Change the load and repeat the above steps A5 to A7 to obtain the compensation current data table; A9. Implement torque ripple suppression in which the compensation current and the compensation voltage are both effective; A10. The compensation current and the compensation voltage are both effective, and the motor speed is changed from high speed to low speed; A11. According to the compensation current in the compensation current data table, the proportional setting unit, and the formula of the voltage equation, calculate the actual q-axis compensation current and d-axis compensation current. If they are inconsistent with the target compensation current, adjust the proportional coefficient, and record the proportional coefficient when they are consistent; A12. Find the approximate function of the proportional coefficient in step A11, or save the proportional coefficient in step A11 as a data table; A13. Change the load and repeat the above step A5 and steps A11 to A12 to obtain the compensation current data table; A14. Implement torque ripple suppression in which the compensation current and the compensation voltage are both effective.
Citation Information
Patent Citations
Apparatus and method for controlling permanent magnet type synchronous motor
JP2002223582A