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Volume 50,Issue 3,2023 Table of Contents
2023, 50(3):1-7.
DOI: 10.12177/emca.2023.010
Abstract:
In the sensorless control of brushless direct current motor (BLDCM), according to the chattering problems of traditional sliding mode observers, a novel non-singular terminal sliding mode observer (NTSMO) is proposed to estimate line back electromotive force. The designed non-singular terminal sliding mode surface can realize fast convergence in finite-time, and a novel sliding mode reaching law is introduced to weaken chattering. The estimation accuracy of back electromotive force is improved, the fast speed observation and control are realized. Finally, the stability of the observer is proved based on the Lyapunov function. The simulation results show that, compared with the traditional method, the proposed NTSMO can effectively suppress chattering and has a good speed estimation accuracy.
In the sensorless control of brushless direct current motor (BLDCM), according to the chattering problems of traditional sliding mode observers, a novel non-singular terminal sliding mode observer (NTSMO) is proposed to estimate line back electromotive force. The designed non-singular terminal sliding mode surface can realize fast convergence in finite-time, and a novel sliding mode reaching law is introduced to weaken chattering. The estimation accuracy of back electromotive force is improved, the fast speed observation and control are realized. Finally, the stability of the observer is proved based on the Lyapunov function. The simulation results show that, compared with the traditional method, the proposed NTSMO can effectively suppress chattering and has a good speed estimation accuracy.
2023, 50(3):8-13.
DOI: 10.12177/emca.2023.001
Abstract:
A nonlinear neural network adaptive backstepping control method is proposed to improve the performance of the magnetic levitation control system of the electrically excited linear synchronous motor (EELSM). The structure and operation mechanism of EELSM are studied. The state equation and mathematical model of EELSM magnetic levitation system are established. In order to overcome the uncertain disturbance existing in the operation of EELSM magnetic levitation platform, a nonlinear neural network adaptive backstepping controller is designed to estimate the disturbance. The stability of the system is proved by constructing the Lyapunov function. The MATLAB software is used to perform computer simulation on the control system, and the simulation results verify the effectiveness of the proposed method.
A nonlinear neural network adaptive backstepping control method is proposed to improve the performance of the magnetic levitation control system of the electrically excited linear synchronous motor (EELSM). The structure and operation mechanism of EELSM are studied. The state equation and mathematical model of EELSM magnetic levitation system are established. In order to overcome the uncertain disturbance existing in the operation of EELSM magnetic levitation platform, a nonlinear neural network adaptive backstepping controller is designed to estimate the disturbance. The stability of the system is proved by constructing the Lyapunov function. The MATLAB software is used to perform computer simulation on the control system, and the simulation results verify the effectiveness of the proposed method.
3 Nonlinear Observer Based Control Design Method for a Class of Dual-Axis Servo System with Rigid Load
2023, 50(3):14-21.
DOI: 10.12177/emca.2022.177
Abstract:
The dual-axis servo system with the LuGre friction model has problems of the position tracking and the speed synchronization. To solve these problems, a nonlinear observer-based command filtered adaptive backstepping control (OCFABC) method is proposed. The observer is used for system friction compensation. The command filter acts on the virtual control signal to solve the computational explosion problem in the backstepping method, and the error compensation equation is established to improve the tracking accuracy. In addition, the speed synchronization signals are designed to achieve the better system synchronization effect. The stability of the closedloop system is analyzed by using Lyapunov theory. Finally, the availability and the superiority of the designed method are demonstrated by simulation and experiment results.
The dual-axis servo system with the LuGre friction model has problems of the position tracking and the speed synchronization. To solve these problems, a nonlinear observer-based command filtered adaptive backstepping control (OCFABC) method is proposed. The observer is used for system friction compensation. The command filter acts on the virtual control signal to solve the computational explosion problem in the backstepping method, and the error compensation equation is established to improve the tracking accuracy. In addition, the speed synchronization signals are designed to achieve the better system synchronization effect. The stability of the closedloop system is analyzed by using Lyapunov theory. Finally, the availability and the superiority of the designed method are demonstrated by simulation and experiment results.
4 Optimization Design of Less-Rare-Earth Halbach Permanent Magnet Synchronous Motor with Module Poles
2023, 50(3):22-28.
DOI: 10.12177/emca.2023.002
Abstract:
The rare earth permanent magnet synchronous motor (PMSM) depends much on the rare earth permanent magnet materials. In order to solve this problem, a lessrareearth PMSM with Halbach array and module poles is proposed. The new structure of the rotor magnetic steel of the motor is described. The main pole of the rotor magnet is composed of two layers of permanent magnets, the outer magnet is made of NdFeB permanent magnet material, the inner magnet is made of ferrite permanent magnet material, and the auxiliary pole magnet is also ferrite permanent magnet material. The electromagnetic torque, the torque ripple and the cogging torque are regarded as optimization criteria. The motor parameters are optimized by using the number of permanent magnets per pole, magnetization angle, permanent magnet material and permanent magnet thickness. A chutetype stator structure is used to reduce cogging torque. The optimized lessrareearth PMSM with module poles reduces the amounts of permanent magnets and reduces the cost of motor while ensuring the torque performance. Finally, the finite element method is used to analyze the performances under the conditions of noload and rated load operation, and to verify the validity and reasonableness of the proposed motor.
The rare earth permanent magnet synchronous motor (PMSM) depends much on the rare earth permanent magnet materials. In order to solve this problem, a lessrareearth PMSM with Halbach array and module poles is proposed. The new structure of the rotor magnetic steel of the motor is described. The main pole of the rotor magnet is composed of two layers of permanent magnets, the outer magnet is made of NdFeB permanent magnet material, the inner magnet is made of ferrite permanent magnet material, and the auxiliary pole magnet is also ferrite permanent magnet material. The electromagnetic torque, the torque ripple and the cogging torque are regarded as optimization criteria. The motor parameters are optimized by using the number of permanent magnets per pole, magnetization angle, permanent magnet material and permanent magnet thickness. A chutetype stator structure is used to reduce cogging torque. The optimized lessrareearth PMSM with module poles reduces the amounts of permanent magnets and reduces the cost of motor while ensuring the torque performance. Finally, the finite element method is used to analyze the performances under the conditions of noload and rated load operation, and to verify the validity and reasonableness of the proposed motor.
2023, 50(3):29-38.
DOI: 10.12177/emca.2023.003
Abstract:
The PI control strategy of motor used for road active ice melting and snow removal spray system is low efficiency and low accuracy. To solve this problem, a speed and current cascade control strategy is presented based on the second-order sliding mode control and active disturbance rejection control (ADRC) technology. The uncertainty mathematical model of three-phase permanent magnet synchronous motor (PMSM) for sprinkler system is established. According to the dynamic model of motor speed, a disturbance observer is designed to estimate the load torque and system uncertainty, and its convergence is proved. At the same time, combined with the super spiral sliding mode control algorithm, a compound speed controller is designed to adjust the motor speed. The results show that the proposed secondorder sliding mode ADRC strategy has a shorter response time, and the regulation time of the motor returning to the rated speed is 60% shorter than that of the PI control strategy, and the speed overshoot is only 48% of that of the PI control strategy. The proposed strategy has better robustness, can realize the full speed domain operation of the motor under the disturbance, and can improve the control accuracy and speed of the spray system.
The PI control strategy of motor used for road active ice melting and snow removal spray system is low efficiency and low accuracy. To solve this problem, a speed and current cascade control strategy is presented based on the second-order sliding mode control and active disturbance rejection control (ADRC) technology. The uncertainty mathematical model of three-phase permanent magnet synchronous motor (PMSM) for sprinkler system is established. According to the dynamic model of motor speed, a disturbance observer is designed to estimate the load torque and system uncertainty, and its convergence is proved. At the same time, combined with the super spiral sliding mode control algorithm, a compound speed controller is designed to adjust the motor speed. The results show that the proposed secondorder sliding mode ADRC strategy has a shorter response time, and the regulation time of the motor returning to the rated speed is 60% shorter than that of the PI control strategy, and the speed overshoot is only 48% of that of the PI control strategy. The proposed strategy has better robustness, can realize the full speed domain operation of the motor under the disturbance, and can improve the control accuracy and speed of the spray system.
2023, 50(3):39-46,64.
DOI: 10.12177/emca.2022.179
Abstract:
In order to improve the global convergence of sliding mode control (SMC) in speed loop control of permanent magnet synchronous motor (PMSM), a compound sliding mode control strategy is proposed, which combines the characteristics of linear sliding mode surface and non-singular terminal sliding mode surface to form a new sliding mode surface and improve the convergence of SMC in different motion stages. On this basis, the traditional power reaching law is improved to reduce the convergence speed in steady state. At the same time, the disturbance observer based on SMC law is used to observe unmodeled dynamics and unknown disturbance of system, the designed SMC is compensated, the dependence of SMC for high gain controller is reduced. Thus, the chattering of controller in the steady state time due to sliding mode highgain effectively is improved, the control performance of SMC is also improved. Finally, the effectiveness and feasibility of the control method are proved by the simulation and the experiment.
In order to improve the global convergence of sliding mode control (SMC) in speed loop control of permanent magnet synchronous motor (PMSM), a compound sliding mode control strategy is proposed, which combines the characteristics of linear sliding mode surface and non-singular terminal sliding mode surface to form a new sliding mode surface and improve the convergence of SMC in different motion stages. On this basis, the traditional power reaching law is improved to reduce the convergence speed in steady state. At the same time, the disturbance observer based on SMC law is used to observe unmodeled dynamics and unknown disturbance of system, the designed SMC is compensated, the dependence of SMC for high gain controller is reduced. Thus, the chattering of controller in the steady state time due to sliding mode highgain effectively is improved, the control performance of SMC is also improved. Finally, the effectiveness and feasibility of the control method are proved by the simulation and the experiment.
2023, 50(3):47-55.
DOI: 10.12177/emca.2023.009
Abstract:
Each phase winding of the open winding brushless direct current motor (BLDCM) is connected to an H-bridge inverter, and its phase voltage and phase current could be controlled independently, which has a certain fault tolerance. The mathematical equations of the openwinding BLDCM are introduced, and the MATLAB simulation model is established. The operation characteristics of the open winding BLDCM under the fault of the power components are analyzed, and the characteristics of two faulttolerant control methods, compensation and reconstruction, are discussed. Finally, the open winding BLDCM and the corresponding controller are processed, and the experimental platform is built. The operation characteristics of the open winding BLDCM under normal operation and fault tolerance compensation operation are verified.
Each phase winding of the open winding brushless direct current motor (BLDCM) is connected to an H-bridge inverter, and its phase voltage and phase current could be controlled independently, which has a certain fault tolerance. The mathematical equations of the openwinding BLDCM are introduced, and the MATLAB simulation model is established. The operation characteristics of the open winding BLDCM under the fault of the power components are analyzed, and the characteristics of two faulttolerant control methods, compensation and reconstruction, are discussed. Finally, the open winding BLDCM and the corresponding controller are processed, and the experimental platform is built. The operation characteristics of the open winding BLDCM under normal operation and fault tolerance compensation operation are verified.
2023, 50(3):56-64.
DOI: 10.12177/emca.2022.180
Abstract:
The oblate spherical powder is an important power source of sniper ammunition, the consistency ofthickness is directly related to the ballistic performance of the projectile. At present, the extrusion molding process of the oblate spherical powder is all applied in rubber industry. Although the functional extrusion can be achieved, there are some problems such as low extrusion accuracy and poor molding consistency. Aiming at the above problems, a set of extruding machine roll distance accurate adjustment system based on particle swarm optimization terminal sliding mode （PSO-TSM） is developed. In this system, particle swarm optimization (PSO) algorithm is used to optimize multiple parameters in terminal sliding mode (TSM) controller iteratively, so as to achieve accurate adjustment of roll distance and improve the consistency of arc thickness. It is verified by extrusion test that the thickness error of the oblate spherical powder is controlled within ±0.02 mm, and the pass rate of extrusion reaches more than 95%.
The oblate spherical powder is an important power source of sniper ammunition, the consistency ofthickness is directly related to the ballistic performance of the projectile. At present, the extrusion molding process of the oblate spherical powder is all applied in rubber industry. Although the functional extrusion can be achieved, there are some problems such as low extrusion accuracy and poor molding consistency. Aiming at the above problems, a set of extruding machine roll distance accurate adjustment system based on particle swarm optimization terminal sliding mode （PSO-TSM） is developed. In this system, particle swarm optimization (PSO) algorithm is used to optimize multiple parameters in terminal sliding mode (TSM) controller iteratively, so as to achieve accurate adjustment of roll distance and improve the consistency of arc thickness. It is verified by extrusion test that the thickness error of the oblate spherical powder is controlled within ±0.02 mm, and the pass rate of extrusion reaches more than 95%.
2023, 50(3):65-71.
DOI: 10.12177/emca.2023.005
Abstract:
The large inertial impulse generator has the problem of excitation control. To solve this problem, a self-adaptive PID control method of whale optimization is proposed. According to the working characteristics of pulse generator and the basic requirements of excitation control, a simplified single-input single-output linear excitation control system of pulse generator is established based on the second-order name-value model of reaction generator parameters varying with speed. The PID control method based on classical control theory is adopted for the system. In order to improve the response time and control accuracy of the system, a parameter self-adaptive PID is designed which adjusts parameters automatically with the error. For the tuning of parameter adjustment coefficient, an optimization problem is constructed with the time weight error integral as the optimization objective and the parameter adjustment coefficient as the optimization variable, and the whale optimization algorithm (WOA) is used to solve the problem. Finally, the control method is simulated, and compared with the whale optimization PID, the rise time of the excitation response under no-load increases from 1.21 s to 0.88 s, and the steady-state error is similar. Under load, the rise time increases from 2.01 s to 1.60 s, and the steady-state error decreases from 4.04% to 1.96%. The effectiveness of the proposed method is verified.
The large inertial impulse generator has the problem of excitation control. To solve this problem, a self-adaptive PID control method of whale optimization is proposed. According to the working characteristics of pulse generator and the basic requirements of excitation control, a simplified single-input single-output linear excitation control system of pulse generator is established based on the second-order name-value model of reaction generator parameters varying with speed. The PID control method based on classical control theory is adopted for the system. In order to improve the response time and control accuracy of the system, a parameter self-adaptive PID is designed which adjusts parameters automatically with the error. For the tuning of parameter adjustment coefficient, an optimization problem is constructed with the time weight error integral as the optimization objective and the parameter adjustment coefficient as the optimization variable, and the whale optimization algorithm (WOA) is used to solve the problem. Finally, the control method is simulated, and compared with the whale optimization PID, the rise time of the excitation response under no-load increases from 1.21 s to 0.88 s, and the steady-state error is similar. Under load, the rise time increases from 2.01 s to 1.60 s, and the steady-state error decreases from 4.04% to 1.96%. The effectiveness of the proposed method is verified.
2023, 50(3):72-80.
DOI: 10.12177/emca.2023.011
Abstract:
The high-speed motor of underwater vehicle has the characteristics of high-speed, high-power and multi-gear adjustable, etc. In order to reduce the torque ripple of high-speed brushless direct current motor (BLDCM) in the limited space of underwater vehicle, the demand for high switching frequency of high-speed motor of underwater vehicle is analyzed. The torque ripple of BLDCM is analyzed mathematically, so the relationship between torque ripple and switching frequency and duty ratio of BLDCM is obtained. The high switching frequency of SiC MOSFET is used to improve the switching frequency of inverter and reduce the torque ripple of highspeed motor. At the same time, SiC MOSFET has the advantage of low switching loss. Therefore, compared with insulated gate bipolar transistor (IGBT), SiC MOSFET can reduce the system efficiency caused by switching loss while improving the switching frequency. Finally，the effect of SiC MOSFET on torque ripple suppression of highspeed BLDCM at higher switching frequency is verified by simulation and experiment, which provides a reference for the application of widebandgap semiconductor devices in highspeed BLDCM of underwater vehicles.
The high-speed motor of underwater vehicle has the characteristics of high-speed, high-power and multi-gear adjustable, etc. In order to reduce the torque ripple of high-speed brushless direct current motor (BLDCM) in the limited space of underwater vehicle, the demand for high switching frequency of high-speed motor of underwater vehicle is analyzed. The torque ripple of BLDCM is analyzed mathematically, so the relationship between torque ripple and switching frequency and duty ratio of BLDCM is obtained. The high switching frequency of SiC MOSFET is used to improve the switching frequency of inverter and reduce the torque ripple of highspeed motor. At the same time, SiC MOSFET has the advantage of low switching loss. Therefore, compared with insulated gate bipolar transistor (IGBT), SiC MOSFET can reduce the system efficiency caused by switching loss while improving the switching frequency. Finally，the effect of SiC MOSFET on torque ripple suppression of highspeed BLDCM at higher switching frequency is verified by simulation and experiment, which provides a reference for the application of widebandgap semiconductor devices in highspeed BLDCM of underwater vehicles.
2023, 50(3):81-87,94.
DOI: 10.12177/emca.2022.176
Abstract:
In order to reduce the permanent magnet cost and improve the performance of external rotor permanent magnet synchronous motor (ERPMSM) for belt conveyor, an optimization method based on response surface methodology (RSM) and improved multi-objective particle swarm optimization (IMOPSO) algorithm is proposed. Based on the establishment of the motor’s basic structure, the permanent magnet size, the air gap length and the slot width are taken as the optimization parameters, and the permanent magnet cost, the output torque, and the torque ripple are taken as the optimization objectives. The significant parameters are screened by sensitivity analysis. The sample space is established based on RSM and finite element simulation, the function relationship between optimization objectives and parameters is fitted. The scheme is optimized by IMOPSO. Finally, the results of comparison of the schemes before and after optimization show that the multi-objective optimization algorithm is accurate and reliable, it has better convergence and diversity, which can optimize the performance of the motor while reducing the cost of permanent magnet simultaneously.
In order to reduce the permanent magnet cost and improve the performance of external rotor permanent magnet synchronous motor (ERPMSM) for belt conveyor, an optimization method based on response surface methodology (RSM) and improved multi-objective particle swarm optimization (IMOPSO) algorithm is proposed. Based on the establishment of the motor’s basic structure, the permanent magnet size, the air gap length and the slot width are taken as the optimization parameters, and the permanent magnet cost, the output torque, and the torque ripple are taken as the optimization objectives. The significant parameters are screened by sensitivity analysis. The sample space is established based on RSM and finite element simulation, the function relationship between optimization objectives and parameters is fitted. The scheme is optimized by IMOPSO. Finally, the results of comparison of the schemes before and after optimization show that the multi-objective optimization algorithm is accurate and reliable, it has better convergence and diversity, which can optimize the performance of the motor while reducing the cost of permanent magnet simultaneously.
2023, 50(3):88-94.
DOI: 10.12177/emca.2022.175
Abstract:
In order to maximize the charging acceptance margin and minimize the fluctuation of wind and solar output, a dual uncertainty optimization model of hybrid AC/DC active distribution network acceptance margin is proposed when the connected power exceeds the distribution network acceptance margin. In order to obtain the dual uncertainty, take the maximization of electric vehicle charging acceptance margin and the minimization of wind and solar power output fluctuation as the goal, and take the node voltage, the wind and solar power output and acceptance margin as the constraints, the distribution network optimization model is built. The solution of optimization model through chaotic binary particle swarm optimization algorithm is introduced to obtain the optimal optimization results after iteration, so the dual uncertainty optimization of distribution network acceptance margin is achieved. The experimental results show that after optimization by this method, the average acceptance capacity of the distribution network increases from 1 200 kW to about 2 000 kW, and it is always within the highquality range of acceptance margin. After the uncertain power type is connected, the maximum voltage out of limit probability of all nodes is 2.7%, and the discarded energy generated by all nodes is kept below 6 MW·h. When all nodes are connected to wind and solar units at peak time, the maximum fluctuation value of wind and solar output is still lower than 3.5 kW·h. When the distribution network is in a harsh environment and the uncertain electric energy is connected daily, the active network loss of the distribution network is between 0.25 MW and 0.40 MW.
In order to maximize the charging acceptance margin and minimize the fluctuation of wind and solar output, a dual uncertainty optimization model of hybrid AC/DC active distribution network acceptance margin is proposed when the connected power exceeds the distribution network acceptance margin. In order to obtain the dual uncertainty, take the maximization of electric vehicle charging acceptance margin and the minimization of wind and solar power output fluctuation as the goal, and take the node voltage, the wind and solar power output and acceptance margin as the constraints, the distribution network optimization model is built. The solution of optimization model through chaotic binary particle swarm optimization algorithm is introduced to obtain the optimal optimization results after iteration, so the dual uncertainty optimization of distribution network acceptance margin is achieved. The experimental results show that after optimization by this method, the average acceptance capacity of the distribution network increases from 1 200 kW to about 2 000 kW, and it is always within the highquality range of acceptance margin. After the uncertain power type is connected, the maximum voltage out of limit probability of all nodes is 2.7%, and the discarded energy generated by all nodes is kept below 6 MW·h. When all nodes are connected to wind and solar units at peak time, the maximum fluctuation value of wind and solar output is still lower than 3.5 kW·h. When the distribution network is in a harsh environment and the uncertain electric energy is connected daily, the active network loss of the distribution network is between 0.25 MW and 0.40 MW.
13 Optimization Method of SOC Calibration for Lithium-Ion Battery in Wind-Solar Energy Storage System
2023, 50(3):95-99,107.
DOI: 10.12177/emca.2023.006
Abstract:
The ampere-hour integral method in industry to estimate the state of charge (SOC) of battery. However, it is impractical to use open circuit voltage (OCV) to calibrate the cumulative error of ampere-hour integral method for wind-solar energy storage systems. Because the OCV method requires the battery to be stationary for several hours. To address this problem, a new calibration method is proposed, which is similar to the OCV method, but its calibration conditions only require the current of battery constant or maintain 4 min fluctuation in a small range, which is more suitable for calibrating the error accumulation problem in wind-solar energy storage systems using the amperehour integral method. 4S6P soft pack lithium-ion batteries is used for experimental testings in 3.9 V, 3.6 V and 3.2 V about three different voltage platforms, the proposed strategy and the actual OCV error were less than 10 mV, and the conversion to SOC is less than 1%, which prove the feasibility of the proposed strategy.
The ampere-hour integral method in industry to estimate the state of charge (SOC) of battery. However, it is impractical to use open circuit voltage (OCV) to calibrate the cumulative error of ampere-hour integral method for wind-solar energy storage systems. Because the OCV method requires the battery to be stationary for several hours. To address this problem, a new calibration method is proposed, which is similar to the OCV method, but its calibration conditions only require the current of battery constant or maintain 4 min fluctuation in a small range, which is more suitable for calibrating the error accumulation problem in wind-solar energy storage systems using the amperehour integral method. 4S6P soft pack lithium-ion batteries is used for experimental testings in 3.9 V, 3.6 V and 3.2 V about three different voltage platforms, the proposed strategy and the actual OCV error were less than 10 mV, and the conversion to SOC is less than 1%, which prove the feasibility of the proposed strategy.
2023, 50(3):100-107.
DOI: 10.12177/emca.2023.007
Abstract:
The air-cooled universal motor used in the household high pressure washer has a problem of overheating in the stator winding. A three-dimensional fluid-solid coupling heat transfer model of the motor is built using an example of an HC8840F air-cooled single-phase series motor. On this foundation, the internal flow field and the temperature field of the series motor are simulated using the fluid-solid coupling heat transfer calculation method. To confirm the validity of the three-dimensional fluid-solid coupling heat transfer model of the universal motor, the stator winding of the motor is subjected to temperature rise test under various working conditions. On this basis, the guidelines for the design of structural optimization are provided. From the perspective of consumption reduction design, the impact of rear fan on the internal flow field and the temperature field of the motor is analysed. The findings demonstrate that the internal fan alters the airflow and make the average temperature of the stator winding decrease by 3.3 ℃.
The air-cooled universal motor used in the household high pressure washer has a problem of overheating in the stator winding. A three-dimensional fluid-solid coupling heat transfer model of the motor is built using an example of an HC8840F air-cooled single-phase series motor. On this foundation, the internal flow field and the temperature field of the series motor are simulated using the fluid-solid coupling heat transfer calculation method. To confirm the validity of the three-dimensional fluid-solid coupling heat transfer model of the universal motor, the stator winding of the motor is subjected to temperature rise test under various working conditions. On this basis, the guidelines for the design of structural optimization are provided. From the perspective of consumption reduction design, the impact of rear fan on the internal flow field and the temperature field of the motor is analysed. The findings demonstrate that the internal fan alters the airflow and make the average temperature of the stator winding decrease by 3.3 ℃.
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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.
