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Volume 46,Issue 7,2019 Table of Contents
2019, 46(7):1-6.
Abstract:
To solve the problem of the base speed change of the permanent magnet synchronous motor (PMSM) caused by the DC bus voltage drop during operation, a fluxweakening control method by adjusting the daxis current of the PMSM based on the DC bus voltage was proposed. When the bus voltage of the motor was lower than the bus voltage required for a given speed as well as the voltage limit ellipse intersected the current limit circle, the daxis current of the motor was adjusted by judging the voltage vector from the current regulator output value and the realtime DC bus voltage, so as to maintain the constant speed. The simulation model was built on MATLAB/Simulink according to the proposed control method. The simulation results verified that the proposed control method could solve the problem of sudden speed change caused by the DC bus voltage drop. Finally, an experimental platform was constructed to validate the effectiveness of the fluxweakening control method.
To solve the problem of the base speed change of the permanent magnet synchronous motor (PMSM) caused by the DC bus voltage drop during operation, a fluxweakening control method by adjusting the daxis current of the PMSM based on the DC bus voltage was proposed. When the bus voltage of the motor was lower than the bus voltage required for a given speed as well as the voltage limit ellipse intersected the current limit circle, the daxis current of the motor was adjusted by judging the voltage vector from the current regulator output value and the realtime DC bus voltage, so as to maintain the constant speed. The simulation model was built on MATLAB/Simulink according to the proposed control method. The simulation results verified that the proposed control method could solve the problem of sudden speed change caused by the DC bus voltage drop. Finally, an experimental platform was constructed to validate the effectiveness of the fluxweakening control method.
2019, 46(7):7-13, 19.
Abstract:
Underwater propeller was an important part of underwater robot. In order to improve its torque response performance, a method of direct torque control of underwater propeller based on sliding mode observer position detection was proposed. The method introduced a hyperbolic tangent function into the line back electromotive force (EMF) sliding mode observer, and this observer was used in underwater propeller direct torque control systems. Therefore, the drive control system performed sector discrimination and torque estimation through the underwater thruster line back EMF observation. Then 6 discrete commutation signals were detained. Finally, the underwater thruster direct torque control without position detection was realized. The simulation implementation showed that the proposed control method could observe the line back EMF value well and improve the torque dynamic response. The system jitter amplitude was small.
Underwater propeller was an important part of underwater robot. In order to improve its torque response performance, a method of direct torque control of underwater propeller based on sliding mode observer position detection was proposed. The method introduced a hyperbolic tangent function into the line back electromotive force (EMF) sliding mode observer, and this observer was used in underwater propeller direct torque control systems. Therefore, the drive control system performed sector discrimination and torque estimation through the underwater thruster line back EMF observation. Then 6 discrete commutation signals were detained. Finally, the underwater thruster direct torque control without position detection was realized. The simulation implementation showed that the proposed control method could observe the line back EMF value well and improve the torque dynamic response. The system jitter amplitude was small.
2019, 46(7):14-19.
Abstract:
Aiming at the problems of integral saturation and DC drift in traditional flux observer, an improved voltagecurrent hybrid model flux observer was proposed. Through the theoretical analysis of the stator flux observer, the traditional voltage model integration method was improved. Combined with the current model flux observer, a voltagecurrent hybrid model flux observer was proposed, which could observe the accurate stator flux in the full speed range. The flux linkage solved the problems of DC offset, amplitude attenuation and phase shift at different speeds. The hybrid flux observer had phase error at the medium speed. To solve this problem, the compensation link was introduced to compensate the output of the hybrid model, which reduced the error caused by the saturation effect, and the dynamic performance of the flux observer was improved. The feasibility and superiority of the improved hybrid model flux observer in the direct torque control of permanent magnet synchronous motor were verified by simulation.
Aiming at the problems of integral saturation and DC drift in traditional flux observer, an improved voltagecurrent hybrid model flux observer was proposed. Through the theoretical analysis of the stator flux observer, the traditional voltage model integration method was improved. Combined with the current model flux observer, a voltagecurrent hybrid model flux observer was proposed, which could observe the accurate stator flux in the full speed range. The flux linkage solved the problems of DC offset, amplitude attenuation and phase shift at different speeds. The hybrid flux observer had phase error at the medium speed. To solve this problem, the compensation link was introduced to compensate the output of the hybrid model, which reduced the error caused by the saturation effect, and the dynamic performance of the flux observer was improved. The feasibility and superiority of the improved hybrid model flux observer in the direct torque control of permanent magnet synchronous motor were verified by simulation.
2019, 46(7):20-25.
Abstract:
The cogging torque of the interior permanent magnet synchronous motor brought a series of problems such as torque ripple, motor control accuracy deterioration, vibration and noise, so it was important to take effective measures to weaken the cogging torque. The influence of radial segmenting of permanent magnet on cogging torque was analyzed by analytic calculation. Based on this, an improved segmenting method of permanent magnet was proposed, which could effectively reduce the influence of permanent magnet segmentation on the back electromotive force and output average torque of motor. In addition, based on the improved nonuniform permanent magnet segmentation, a new method of unequal thickness and nonuniform permanent magnet segmentation was proposed. Three methods of uniform permanent magnet segmentation, nonuniform permanent magnet segmentation and unequal thickness and nonuniform permanent magnet segmentation were verified and compared by the finite element method. The simulation results showed that the cogging torque attenuation effect of the new method of unequal thickness and nonuniform permanent magnet segmentation was the best.
The cogging torque of the interior permanent magnet synchronous motor brought a series of problems such as torque ripple, motor control accuracy deterioration, vibration and noise, so it was important to take effective measures to weaken the cogging torque. The influence of radial segmenting of permanent magnet on cogging torque was analyzed by analytic calculation. Based on this, an improved segmenting method of permanent magnet was proposed, which could effectively reduce the influence of permanent magnet segmentation on the back electromotive force and output average torque of motor. In addition, based on the improved nonuniform permanent magnet segmentation, a new method of unequal thickness and nonuniform permanent magnet segmentation was proposed. Three methods of uniform permanent magnet segmentation, nonuniform permanent magnet segmentation and unequal thickness and nonuniform permanent magnet segmentation were verified and compared by the finite element method. The simulation results showed that the cogging torque attenuation effect of the new method of unequal thickness and nonuniform permanent magnet segmentation was the best.
2019, 46(7):26-30.
Abstract:
A speed identification approach based on the back electromotive force (EMF) was proposed for the induction motor vector control system using cascaded inverter. The method used the backEMF as the system model output to construct the model reference adaptive system (MRAS). MRAS used a reference model and adjustable model parallel structure to achieve speed identification. The problems caused by pure integral part were eliminated. The proposed method was applied to the induction motor vector control system. The simulation and experiment systems were implemented. Simulation and experiment results showed that the method was easy to implement and could accurately estimate the motor speed.
A speed identification approach based on the back electromotive force (EMF) was proposed for the induction motor vector control system using cascaded inverter. The method used the backEMF as the system model output to construct the model reference adaptive system (MRAS). MRAS used a reference model and adjustable model parallel structure to achieve speed identification. The problems caused by pure integral part were eliminated. The proposed method was applied to the induction motor vector control system. The simulation and experiment systems were implemented. Simulation and experiment results showed that the method was easy to implement and could accurately estimate the motor speed.
2019, 46(7):31-38.
Abstract:
Aiming at the poor operation of doubly fed induction generator under unbalanced grid voltage, neural network sliding mode controller, which combined neural network control with secondorder sliding mode control, was applied to direct power control of doubly fed wind generator. A secondorder sliding mode controller was designed. The secondorder sliding mode could effectively weaken the chattering of traditional sliding mode control. At the same time, a radial basis function neural network was designed to approximate the uncertain part of the system. Finally, based on Lyapunov stability theory, the adaptive law of the neural network weight was deduced, and the stability of the control system was proved. The simulation results showed that the proposed control strategy could effectively control the active power, reactive power and stator current, and weaken the chattering in traditional sliding mode control.
Aiming at the poor operation of doubly fed induction generator under unbalanced grid voltage, neural network sliding mode controller, which combined neural network control with secondorder sliding mode control, was applied to direct power control of doubly fed wind generator. A secondorder sliding mode controller was designed. The secondorder sliding mode could effectively weaken the chattering of traditional sliding mode control. At the same time, a radial basis function neural network was designed to approximate the uncertain part of the system. Finally, based on Lyapunov stability theory, the adaptive law of the neural network weight was deduced, and the stability of the control system was proved. The simulation results showed that the proposed control strategy could effectively control the active power, reactive power and stator current, and weaken the chattering in traditional sliding mode control.
2019, 46(7):39-44.
Abstract:
The use of mechanical sensors would increase the cost and failure rate of the speed control system. The permanent magnet synchronous motor (PMSM) position sensorless vector control system was designed based on model reference adaptive system (MRAS). The MRAS algorithm was used to obtain the speed and position of the PMSM vector speed control system. Appropriate adaptive law was selected for the system. The system was proved to satisfy the Popov hyperstability condition, ensuring the asymptotic stability of the system. Finally, simulation model was built by using MATLAB/Simulink. The simulation results showed that the designed position sensorless speed control system had good control performance under the conditions of sudden load change and dynamic speed change.
The use of mechanical sensors would increase the cost and failure rate of the speed control system. The permanent magnet synchronous motor (PMSM) position sensorless vector control system was designed based on model reference adaptive system (MRAS). The MRAS algorithm was used to obtain the speed and position of the PMSM vector speed control system. Appropriate adaptive law was selected for the system. The system was proved to satisfy the Popov hyperstability condition, ensuring the asymptotic stability of the system. Finally, simulation model was built by using MATLAB/Simulink. The simulation results showed that the designed position sensorless speed control system had good control performance under the conditions of sudden load change and dynamic speed change.
2019, 46(7):45-50.
Abstract:
The brushless doublyfed motor (BDFM), without a brush gear, provided the benefits of low maintenance cost and high reliability, so it had broad application prospects in the field of variablespeed constantfrequency (VSCF) wind power generation. Because of its special structure and principle of operation, the mathematical models of BDFM were very complicated. Based on multiloop space vector model of BDFM, a new method to derive static reference frame models of the power winding and the control winding was proposed, and the coordinate conversion between them was given. The derivation was simple and clear. The conclusions provided a theoretical basis for the theoretical analysis and control strategy of BDFM. The simulation results in MATLAB/Simulink showed that the static reference frame models and coordinate transformation were correct.
The brushless doublyfed motor (BDFM), without a brush gear, provided the benefits of low maintenance cost and high reliability, so it had broad application prospects in the field of variablespeed constantfrequency (VSCF) wind power generation. Because of its special structure and principle of operation, the mathematical models of BDFM were very complicated. Based on multiloop space vector model of BDFM, a new method to derive static reference frame models of the power winding and the control winding was proposed, and the coordinate conversion between them was given. The derivation was simple and clear. The conclusions provided a theoretical basis for the theoretical analysis and control strategy of BDFM. The simulation results in MATLAB/Simulink showed that the static reference frame models and coordinate transformation were correct.
2019, 46(7):51-55.
Abstract:
For the high power density brushless DC motor of aircraft, a threedimensional thermal simulation model of motor and controller was established. According to the theory of heat exchange and heat transfer in the motor system, the internal heat transfer coefficient and boundary conditions were determined. Using ANSYS Workbench software, simulation and analysis were carried out for the temperature field of the established thermal model. The temperature field distribution and temperature curves of the motor and controller were obtained under different operating conditions. The results were compared with the experimental data. The accuracy of simulation was verified, which provided the basis for the design of the motor and controller as well as the calculation of the temperature field.
For the high power density brushless DC motor of aircraft, a threedimensional thermal simulation model of motor and controller was established. According to the theory of heat exchange and heat transfer in the motor system, the internal heat transfer coefficient and boundary conditions were determined. Using ANSYS Workbench software, simulation and analysis were carried out for the temperature field of the established thermal model. The temperature field distribution and temperature curves of the motor and controller were obtained under different operating conditions. The results were compared with the experimental data. The accuracy of simulation was verified, which provided the basis for the design of the motor and controller as well as the calculation of the temperature field.
2019, 46(7):56-61, 88.
Abstract:
The high precision slotless disctype permanent magnet motor was studied. A threedimensional electromagnetic model of the machine was established. The back electromotive force and torque were analyzed. The eddy current losses of stator, rotor and permanent magnet caused by high order harmonics could be avoided. The thermal performance was improved and the foundation for further study could be provided. Then, the threedimensional temperature field model was built. The heat source distribution and heat transfer process were analyzed. The steady state temperature field distribution of the machine under natural heat dissipation condition was calculated. Finally, the validity and reasonability of the theoretical analysis were verified by the temperature rise experiment.
The high precision slotless disctype permanent magnet motor was studied. A threedimensional electromagnetic model of the machine was established. The back electromotive force and torque were analyzed. The eddy current losses of stator, rotor and permanent magnet caused by high order harmonics could be avoided. The thermal performance was improved and the foundation for further study could be provided. Then, the threedimensional temperature field model was built. The heat source distribution and heat transfer process were analyzed. The steady state temperature field distribution of the machine under natural heat dissipation condition was calculated. Finally, the validity and reasonability of the theoretical analysis were verified by the temperature rise experiment.
2019, 46(7):62-66.
Abstract:
Using a 10 kV3 000 kW2 pole highvoltage highspeed motor as an example, the statics of the shaft were analyzed under the rotor eccentricity. An analysis method and a finite element method were proposed for the unilateral magnetic force, and the deflection of the shaft with axial ventilation slots was calculated. Then, the statics of the shaft were analyzed by ANSYS Workbench finite element simulation software. The analysis method could be used on the basis of ensuring the calculation accuracy. A reference for the unilateral magnetic force and the static analysis on the shaft of the highvoltage highspeed motor was provided.
Using a 10 kV3 000 kW2 pole highvoltage highspeed motor as an example, the statics of the shaft were analyzed under the rotor eccentricity. An analysis method and a finite element method were proposed for the unilateral magnetic force, and the deflection of the shaft with axial ventilation slots was calculated. Then, the statics of the shaft were analyzed by ANSYS Workbench finite element simulation software. The analysis method could be used on the basis of ensuring the calculation accuracy. A reference for the unilateral magnetic force and the static analysis on the shaft of the highvoltage highspeed motor was provided.
2019, 46(7):67-71, 81.
Abstract:
As a wind power generation method, directdrive permanent synchronous windpower generator had the advantages of simple structure, low cost, and reliable operation, so it had potential application value in the wind power generation field. Taking a 1 200 kW directdrive permanent magnet synchronous windpower generator as the research object, the coupling analysis of electromagnetic field, temperature field and thermal stress field was carried out, and the influences of temperature change and thermal deformation on the properties of permanent magnet, copper wire and other electromagnetic materials were considered, achieving the convergence of electromagnetic performances, temperature and deformation, so that the performances of the generator could be more accurately analyzed. The stator winding optimum design of the generator was carried out through the multiphysicalfield coupling analysis method, which made the winding design more reasonable. The conclusions had certain reference value for the design of directdrive permanent magnet synchronous windpower generator.
As a wind power generation method, directdrive permanent synchronous windpower generator had the advantages of simple structure, low cost, and reliable operation, so it had potential application value in the wind power generation field. Taking a 1 200 kW directdrive permanent magnet synchronous windpower generator as the research object, the coupling analysis of electromagnetic field, temperature field and thermal stress field was carried out, and the influences of temperature change and thermal deformation on the properties of permanent magnet, copper wire and other electromagnetic materials were considered, achieving the convergence of electromagnetic performances, temperature and deformation, so that the performances of the generator could be more accurately analyzed. The stator winding optimum design of the generator was carried out through the multiphysicalfield coupling analysis method, which made the winding design more reasonable. The conclusions had certain reference value for the design of directdrive permanent magnet synchronous windpower generator.
2019, 46(7):72-75, 93.
Abstract:
For the product standardization and generic design of slip ring of traction generator, five types of slip ring insulation structures for AC drive diesel locomotive traction generator were introduced. An optimization scheme for the insulation structure of slip ring was proposed. The results of tests, experiments and finite element analysis showed that the optimized structure could meet the requirements of traction generator with rated voltage less than 1 346 V. The reference was provided for the later design of insulation structure of slip ring with different requirements.
For the product standardization and generic design of slip ring of traction generator, five types of slip ring insulation structures for AC drive diesel locomotive traction generator were introduced. An optimization scheme for the insulation structure of slip ring was proposed. The results of tests, experiments and finite element analysis showed that the optimized structure could meet the requirements of traction generator with rated voltage less than 1 346 V. The reference was provided for the later design of insulation structure of slip ring with different requirements.
2019, 46(7):76-81.
Abstract:
In order to detect the phase current in real time, the traditional power inverter circuit for brushless DC motor (BLDCM) controller of electric vehicle sampled the phase current through the resistor and fed it back to the microcontroller unit (MCU) for current loop closedloop control. However, when the controller was used in high power levels, the heavy current would cause some power loss. In order to solve the problem, a set of electric vehicle controller circuits with STM32 series microchip as the core was designed. The hardware controller of BLDCM was described in detail. To improve the shortcircuit protection circuit of power supply, a new method for sampling internal resistance of MOS tube was especially proposed, and a PCB based on aluminum substrate was made. The test results showed that the designed circuits performed reliably and could be applied to industrial production.
In order to detect the phase current in real time, the traditional power inverter circuit for brushless DC motor (BLDCM) controller of electric vehicle sampled the phase current through the resistor and fed it back to the microcontroller unit (MCU) for current loop closedloop control. However, when the controller was used in high power levels, the heavy current would cause some power loss. In order to solve the problem, a set of electric vehicle controller circuits with STM32 series microchip as the core was designed. The hardware controller of BLDCM was described in detail. To improve the shortcircuit protection circuit of power supply, a new method for sampling internal resistance of MOS tube was especially proposed, and a PCB based on aluminum substrate was made. The test results showed that the designed circuits performed reliably and could be applied to industrial production.
2019, 46(7):82-88.
Abstract:
The great progress in the development of brushless DC motor (BLDCM) from the traditional brush DC motor to the widely used BLDCM was described. Based on the TI C2000 series digital signal processing (DSP) chip and DRV8301 frontdrive chip, a set of BLDCM sensorless drive control system to solve these problems and deficiencies was designed, and the main circuit design and main program flow were given. This control system scheme had many advantages such as good operation stability, superior control performance, low cost, small volume, and easy to use compared with the traditional control system scheme.
The great progress in the development of brushless DC motor (BLDCM) from the traditional brush DC motor to the widely used BLDCM was described. Based on the TI C2000 series digital signal processing (DSP) chip and DRV8301 frontdrive chip, a set of BLDCM sensorless drive control system to solve these problems and deficiencies was designed, and the main circuit design and main program flow were given. This control system scheme had many advantages such as good operation stability, superior control performance, low cost, small volume, and easy to use compared with the traditional control system scheme.
2019, 46(7):89-93.
Abstract:
The scheme of elevator drive system test rig was introduced when fourquadrant variable frequency static power supply and ACS880 frequency converter were used as test power supply and loading system power supply, respectively. The highprecision and lowuncertainty test rig was realized by using Yokogawa WT1800E sixchannel electrical parameter measuring instrument, the CT series wideband current sensor and the Kistler dualrange torquespeed sensor. The test rig used the energy closed loop feedback method to carry out the drag loading test, which could meet the requirement of comprehensive performance test of the elevator drive systems with the rated power of 30 kW or lower. The field testing showed that the equipment ran stably and reliably, the test was flexible, and the operation was simple and convenient. This method possessed high design reference value.
The scheme of elevator drive system test rig was introduced when fourquadrant variable frequency static power supply and ACS880 frequency converter were used as test power supply and loading system power supply, respectively. The highprecision and lowuncertainty test rig was realized by using Yokogawa WT1800E sixchannel electrical parameter measuring instrument, the CT series wideband current sensor and the Kistler dualrange torquespeed sensor. The test rig used the energy closed loop feedback method to carry out the drag loading test, which could meet the requirement of comprehensive performance test of the elevator drive systems with the rated power of 30 kW or lower. The field testing showed that the equipment ran stably and reliably, the test was flexible, and the operation was simple and convenient. This method possessed high design reference value.
2019, 46(7):94-99.
Abstract:
The existence of IGBT deadtime effect made the output current of threephase gridconnected inverters unable to track the reference current accurately, which led to poor control performance. However, the traditional deadtime compensation method had the problem of inaccurate current polarity judgment when the phase current was zero. Based on the above problems, a deadtime compensation method for threephase gridconnected inverter based on fuzzyadaptive PI strategy was proposed. The disturbance observer was applied to the current doubleloop fuzzyadaptive PI control system. The voltage error caused by deadtime effect was regarded as an external disturbance. After the estimation of the disturbance observer, the voltage error was fed back to the input to counteract the deadtime effect. Fuzzyadaptive PI current doubleloop control strategy could solve the problems of slow response and poor dynamic characteristics of the actual system. The simulation of MATLAB/Simulink and experiment showed that the method could effectively reduce the influence of deadtime effect and improve the dynamic response of the system.
The existence of IGBT deadtime effect made the output current of threephase gridconnected inverters unable to track the reference current accurately, which led to poor control performance. However, the traditional deadtime compensation method had the problem of inaccurate current polarity judgment when the phase current was zero. Based on the above problems, a deadtime compensation method for threephase gridconnected inverter based on fuzzyadaptive PI strategy was proposed. The disturbance observer was applied to the current doubleloop fuzzyadaptive PI control system. The voltage error caused by deadtime effect was regarded as an external disturbance. After the estimation of the disturbance observer, the voltage error was fed back to the input to counteract the deadtime effect. Fuzzyadaptive PI current doubleloop control strategy could solve the problems of slow response and poor dynamic characteristics of the actual system. The simulation of MATLAB/Simulink and experiment showed that the method could effectively reduce the influence of deadtime effect and improve the dynamic response of the system.
2019, 46(7):100-104.
Abstract:
In order to improve the control performance of the module of the inverting circuit, a control method of the inverting circuit based on integral separation and deadtime PID control was proposed. This control method could effectively solve the problem that the control quantity caused by the traditional PID control exceeded the controlled object, thus leading to the system oscillation. Integral separation and deadtime PID control algorithm introduced deadtime PID control algorithm into integral separation PID control algorithm. By combining the advantages of the two control algorithms, it could not only prolong the service life of the control system, but also limit the system deviation. Finally, the simulation model of high frequency power supply with inverting circuit module was established by MATLAB/Simulink, and the effectiveness and practicability of the proposed PID control method were verified.
In order to improve the control performance of the module of the inverting circuit, a control method of the inverting circuit based on integral separation and deadtime PID control was proposed. This control method could effectively solve the problem that the control quantity caused by the traditional PID control exceeded the controlled object, thus leading to the system oscillation. Integral separation and deadtime PID control algorithm introduced deadtime PID control algorithm into integral separation PID control algorithm. By combining the advantages of the two control algorithms, it could not only prolong the service life of the control system, but also limit the system deviation. Finally, the simulation model of high frequency power supply with inverting circuit module was established by MATLAB/Simulink, and the effectiveness and practicability of the proposed PID control method were verified.
2019, 46(7):105-110.
Abstract:
A high gain boost converter circuit topology was proposed. When the circuit operated at duty cycle D>0.5, the voltage gain was three times that of conventional boost converter. The voltage stress of active switch was equalized and reduced to 1/3 of the output voltage. The converter topology of twochannel compound branch of high gain threeterminal network was deduced. The principle and characteristics of the circuit were analyzed. Finally, a 140 W experimental prototype was built to verify the correctness of the theoretical study.
A high gain boost converter circuit topology was proposed. When the circuit operated at duty cycle D>0.5, the voltage gain was three times that of conventional boost converter. The voltage stress of active switch was equalized and reduced to 1/3 of the output voltage. The converter topology of twochannel compound branch of high gain threeterminal network was deduced. The principle and characteristics of the circuit were analyzed. Finally, a 140 W experimental prototype was built to verify the correctness of the theoretical study.
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Electric Machines & Control Application ® 2025
Supported by:Beijing E-Tiller Technology Development Co., Ltd.
沪ICP备16038578号-3
Electric Machines & Control Application ® 2025
Supported by:Beijing E-Tiller Technology Development Co., Ltd.
