Mobile website
Volume 49,Issue 8,2022 Table of Contents
2022, 49(8):1-6.
DOI: 10.12177/emca.2022.071
Abstract:
Brushless DC motor (BLDCM) drive system is applied in multi-electric/all-electric aircrafts to provide power output for electric fuel pump, cooling pump and electric brake. In order to meet the special working environments such as complex electromagnetic interference and extreme temperature, a sliding mode back electromotive force (EMF) observer based on variable structure control strategy is proposed to realize the position sensorless control of motor. The variable reaching law is used to replace the fixed gain of the traditional sliding mode back EMF observer, and the rotor position and speed information of the motor are obtained through the phase-locked loop (PLL). The simulation results show that the method can effectively suppress the chattering of the observed value of back EMF, realize the stable operation of the motor in the middle and high speed stage, and meet the requirements of rapidity and robustness of the system.
Brushless DC motor (BLDCM) drive system is applied in multi-electric/all-electric aircrafts to provide power output for electric fuel pump, cooling pump and electric brake. In order to meet the special working environments such as complex electromagnetic interference and extreme temperature, a sliding mode back electromotive force (EMF) observer based on variable structure control strategy is proposed to realize the position sensorless control of motor. The variable reaching law is used to replace the fixed gain of the traditional sliding mode back EMF observer, and the rotor position and speed information of the motor are obtained through the phase-locked loop (PLL). The simulation results show that the method can effectively suppress the chattering of the observed value of back EMF, realize the stable operation of the motor in the middle and high speed stage, and meet the requirements of rapidity and robustness of the system.
2022, 49(8):7-13.
DOI: 10.12177/emca.2022.079
Abstract:
To overcome the problem of using low-efficiency and high-precision 3D finite element simulation in axial topology simulation of double skewed induction motor, an equivalent circuit is proposed for the staggered double skewed rotor induction motor (DSRIM) and then the axially layered equivalent circuit of DSRIM is established based on the multi-layer finite element model. Based on the coupling analysis of the equivalent circuit and the magnetic field, the air-gap magnetic field distribution and steady-state performance index are obtained by using the distributed magnetic circuit method. The calculation results are compared with the experimental results, and it is shown that the calculation results of this method have guiding significance.
To overcome the problem of using low-efficiency and high-precision 3D finite element simulation in axial topology simulation of double skewed induction motor, an equivalent circuit is proposed for the staggered double skewed rotor induction motor (DSRIM) and then the axially layered equivalent circuit of DSRIM is established based on the multi-layer finite element model. Based on the coupling analysis of the equivalent circuit and the magnetic field, the air-gap magnetic field distribution and steady-state performance index are obtained by using the distributed magnetic circuit method. The calculation results are compared with the experimental results, and it is shown that the calculation results of this method have guiding significance.
2022, 49(8):14-20.
DOI: 10.12177/emca.2022.069
Abstract:
In order to improve the dynamic response performance of direct-drive permanent magnet synchronous motor (DD-PMSM), an improved deadbeat direct torque control (DB-DTC) strategy is proposed. On the basis of retaining the dynamic response performance of traditional DB-DTC, the improved DB-DTC simplifies the control process and reduces the amount of real-time calculation. The control effects of traditional DB-DTC and improved DB-DTC are compared by building a simulation model in MATLAB/Simulink, and the advantages of the proposed control strategy are verified by combining the improved DB-DTC with the position type impedance control strategy. The simulation results show that in the position control mode, compared with the traditional DB-DTC, the time required for the motor to rotate to a given angle and decelerate to zero speed is reduced by 0.002 s, and the steady-state operation angle error is reduced by 0.02°. In the speed control mode, compared with the traditional DB-DTC, the time to reach the given speed is reduced by 0.004 s, the steady-state speed error is reduced by 0.03 r/min, and the steady-state speed fluctuation is reduced by 0.06 r/min. After the motor enters steady-state operation, the q axis peak current is reduced by 0.193 A, and the pulsation of q axis current is reduced by 0.204 A. The motor control system has better dynamic performance and stronger anti-interference ability.
In order to improve the dynamic response performance of direct-drive permanent magnet synchronous motor (DD-PMSM), an improved deadbeat direct torque control (DB-DTC) strategy is proposed. On the basis of retaining the dynamic response performance of traditional DB-DTC, the improved DB-DTC simplifies the control process and reduces the amount of real-time calculation. The control effects of traditional DB-DTC and improved DB-DTC are compared by building a simulation model in MATLAB/Simulink, and the advantages of the proposed control strategy are verified by combining the improved DB-DTC with the position type impedance control strategy. The simulation results show that in the position control mode, compared with the traditional DB-DTC, the time required for the motor to rotate to a given angle and decelerate to zero speed is reduced by 0.002 s, and the steady-state operation angle error is reduced by 0.02°. In the speed control mode, compared with the traditional DB-DTC, the time to reach the given speed is reduced by 0.004 s, the steady-state speed error is reduced by 0.03 r/min, and the steady-state speed fluctuation is reduced by 0.06 r/min. After the motor enters steady-state operation, the q axis peak current is reduced by 0.193 A, and the pulsation of q axis current is reduced by 0.204 A. The motor control system has better dynamic performance and stronger anti-interference ability.
2022, 49(8):21-27.
DOI: 10.12177/emca.2022.064
Abstract:
With the development of more-electric and all-electric, aircraft electrical and electronic equipment has increased greatly, and the constant frequency system can no longer meet the demand of aircraft power. The aircraft power supply system needs to transform from constant frequency system to variable frequency system, and variable frequency generator is the most important equipment in variable frequency system. The traditional PID control adopts fixed parameters and cannot work well in the wide variable frequency power generation system, so a control parameter modification method based on fuzzy backstepping adaptive control algorithm is proposed to improve the adaptability of the voltage regulating system. Combined with the mathematical model of three-stage power generation system, an adaptive law analysis method for uncertain parameters in the voltage regulating system is designed, and a simulation model of the voltage regulating system based on the algorithm is established. The simulation results showed that the fuzzy backstepping adaptive control could effectively suppress the influence of working condition changes on the voltage regulating system, enhance the stability and regulation performance of the voltage regulating system, and this algorithm provides theoretical support for the design of aircraft generator controller.
With the development of more-electric and all-electric, aircraft electrical and electronic equipment has increased greatly, and the constant frequency system can no longer meet the demand of aircraft power. The aircraft power supply system needs to transform from constant frequency system to variable frequency system, and variable frequency generator is the most important equipment in variable frequency system. The traditional PID control adopts fixed parameters and cannot work well in the wide variable frequency power generation system, so a control parameter modification method based on fuzzy backstepping adaptive control algorithm is proposed to improve the adaptability of the voltage regulating system. Combined with the mathematical model of three-stage power generation system, an adaptive law analysis method for uncertain parameters in the voltage regulating system is designed, and a simulation model of the voltage regulating system based on the algorithm is established. The simulation results showed that the fuzzy backstepping adaptive control could effectively suppress the influence of working condition changes on the voltage regulating system, enhance the stability and regulation performance of the voltage regulating system, and this algorithm provides theoretical support for the design of aircraft generator controller.
2022, 49(8):28-33.
DOI: 10.12177/emca.2022.078
Abstract:
The traditional PI optimization method is difficult to meet the application of permanent magnet synchronous motor (PMSM) in highspeed, highprecision and load change. Therefore, based on the honey badger algorithm (HBA), combined with the tent map and normal cloud, an improved HBA is designed to optimize the PI parameters, so as to improve the control accuracy and speed of the PMSM speed loop and current loop control. The tent map is used to improve the distribution uniformity in the initialization stage of the algorithm and strengthen the global development ability in the early stage of the algorithm; The second group of honey badgers is generated by using the normal cloud to update the best position in the same generation, and strengthen the ability of jumping out of the local optimization. During the optimization process, the normal cloud model is dynamically changed to improve the local search ability. Using MATLAB/Simulink for simulation comparison, the improved HBA has certain advantages in adjustment time, stability and so on. It is a new algorithm that can be used in PMSM speed control system.
The traditional PI optimization method is difficult to meet the application of permanent magnet synchronous motor (PMSM) in highspeed, highprecision and load change. Therefore, based on the honey badger algorithm (HBA), combined with the tent map and normal cloud, an improved HBA is designed to optimize the PI parameters, so as to improve the control accuracy and speed of the PMSM speed loop and current loop control. The tent map is used to improve the distribution uniformity in the initialization stage of the algorithm and strengthen the global development ability in the early stage of the algorithm; The second group of honey badgers is generated by using the normal cloud to update the best position in the same generation, and strengthen the ability of jumping out of the local optimization. During the optimization process, the normal cloud model is dynamically changed to improve the local search ability. Using MATLAB/Simulink for simulation comparison, the improved HBA has certain advantages in adjustment time, stability and so on. It is a new algorithm that can be used in PMSM speed control system.
2022, 49(8):34-40.
DOI: 10.12177/emca.2022.063
Abstract:
For the purpose of optimizing the parameters of electric locomotive traction electric drive system for more reasonable matching relationship, an automatic optimization method for the key parameters of electric locomotive traction electric drive system is studied. Firstly, the traction electric drive system simulation model of a certain electric locomotive is established, and the simulation results prove the accuracy and rationality of the modeling method. Secondly, simulation based on design of experiment (DOE) of the model is carried out, and a cluster of simulation results reflecting the system operation law is obtained. Based on the simulation results, an approximate model mapping the input parameters and output characteristics of the system is established. Thirdly, the optimized design parameters are obtained by the multi-objective particle swarm optimization algorithm. Finally, the results of simulation optimization of several models are compared and analyzed, which verifies the effect of the global optimization method based on the approximate model, and high simulation efficiency is achieved as well as high simulation accuracy. The research has certain reference value for the high-efficiency simulation of electric locomotive traction electric drive system.
For the purpose of optimizing the parameters of electric locomotive traction electric drive system for more reasonable matching relationship, an automatic optimization method for the key parameters of electric locomotive traction electric drive system is studied. Firstly, the traction electric drive system simulation model of a certain electric locomotive is established, and the simulation results prove the accuracy and rationality of the modeling method. Secondly, simulation based on design of experiment (DOE) of the model is carried out, and a cluster of simulation results reflecting the system operation law is obtained. Based on the simulation results, an approximate model mapping the input parameters and output characteristics of the system is established. Thirdly, the optimized design parameters are obtained by the multi-objective particle swarm optimization algorithm. Finally, the results of simulation optimization of several models are compared and analyzed, which verifies the effect of the global optimization method based on the approximate model, and high simulation efficiency is achieved as well as high simulation accuracy. The research has certain reference value for the high-efficiency simulation of electric locomotive traction electric drive system.
2022, 49(8):41-46.
DOI: 10.12177/emca.2022.080
Abstract:
With the rapid development of smart grid, the problem of nonintrusive load monitoring (NILM) and disaggregation has been widely concerned in order to effectively improve the utilization of power, rationally plan the power resources, and establish the nationwide smart power and load monitoring system. To improve the performance of nonintrusive load disaggregation, a nonintrusive load disaggregation method based on coupled neural network is presented. Firstly, the dataset is normalized and preprocessed. Secondly, a hybrid deep learning model is constructed, which combines convolution neural network (CNN) with bidirectional gated recurrent unit (BiGRU). The spatial and temporal characteristics of data are fully explored, and attention mechanism is added to focus on important information and eliminate redundant features. Finally, the domestic selftest data set is used for the experiment, and the coupled neural network is evaluated with different evaluation indexes, and compared with other commonly used disaggregation models. The experimental results show that the mean absolute error and sum of absolute error of the proposed method are reduced compared with other disaggregation methods, the mean absolute error is reduced by 35.9% and the sum of absolute error is reduced by 39.9% on average.
With the rapid development of smart grid, the problem of nonintrusive load monitoring (NILM) and disaggregation has been widely concerned in order to effectively improve the utilization of power, rationally plan the power resources, and establish the nationwide smart power and load monitoring system. To improve the performance of nonintrusive load disaggregation, a nonintrusive load disaggregation method based on coupled neural network is presented. Firstly, the dataset is normalized and preprocessed. Secondly, a hybrid deep learning model is constructed, which combines convolution neural network (CNN) with bidirectional gated recurrent unit (BiGRU). The spatial and temporal characteristics of data are fully explored, and attention mechanism is added to focus on important information and eliminate redundant features. Finally, the domestic selftest data set is used for the experiment, and the coupled neural network is evaluated with different evaluation indexes, and compared with other commonly used disaggregation models. The experimental results show that the mean absolute error and sum of absolute error of the proposed method are reduced compared with other disaggregation methods, the mean absolute error is reduced by 35.9% and the sum of absolute error is reduced by 39.9% on average.
2022, 49(8):47-52.
DOI: 10.12177/emca.2022.072
Abstract:
Aiming at the problem of end force minimization of permanent magnet linear synchronous motor（PMLSM），an effectively method to weaken the end force by adding auxiliary iron core at the both ends of the primary iron core is proposed. Firstly, the mechanism of the end force and the electromagnetic force on the tooth wall are analyzed. When the height of the auxiliary iron core at both ends of the primary iron core is an air gap length, and the length is 1/4 permanent magnet pole distance, the end force has the minimum value. Taking a 36-slot/12-pole axial-magnetized tubular permanent magnet linear synchronous motor (TPMLSM) as an example, the finite element simulation analysis and experimental test are carried out. The finite element analysis value is in good agreement with the experimental value, which proves that the proposed method can effectively weaken the end force of PMLSM, and also provides a simple and effective method of the end force minimization for PMLSM.
Aiming at the problem of end force minimization of permanent magnet linear synchronous motor（PMLSM），an effectively method to weaken the end force by adding auxiliary iron core at the both ends of the primary iron core is proposed. Firstly, the mechanism of the end force and the electromagnetic force on the tooth wall are analyzed. When the height of the auxiliary iron core at both ends of the primary iron core is an air gap length, and the length is 1/4 permanent magnet pole distance, the end force has the minimum value. Taking a 36-slot/12-pole axial-magnetized tubular permanent magnet linear synchronous motor (TPMLSM) as an example, the finite element simulation analysis and experimental test are carried out. The finite element analysis value is in good agreement with the experimental value, which proves that the proposed method can effectively weaken the end force of PMLSM, and also provides a simple and effective method of the end force minimization for PMLSM.
2022, 49(8):53-58.
DOI: 10.12177/emca.2022.068
Abstract:
Aiming at the problem of increasing the output torque of the dual three-phase permanent magnet synchronous motor (PMSM), the control principle of the 3rd harmonic current injection into the motor phase current and back electromotive force (EMF) is analyzed. The motor drive system is optimized, and the 3rd harmonic current is adjusted to solve current interference problem of two sets of windings. On the basis of the optimal phase current, a permanent magnet shaping method is proposed, which comprehensively considers the stator cogging effect, iron core saturation and magnetic leakage between tooth tips and poles, and the optimal quasi-sinusoidal back EMF is obtained. The output torque of the motor is increased by 18.1% due to the interaction of quasi-sinusoidal current and quasi-sinusoidal back EMF. Finally, the correctness of the theoretical derivation is verified through finite element analysis and experiments, which provides technical support for the large-scale application of high reliability dual three-phase PMSM.
Aiming at the problem of increasing the output torque of the dual three-phase permanent magnet synchronous motor (PMSM), the control principle of the 3rd harmonic current injection into the motor phase current and back electromotive force (EMF) is analyzed. The motor drive system is optimized, and the 3rd harmonic current is adjusted to solve current interference problem of two sets of windings. On the basis of the optimal phase current, a permanent magnet shaping method is proposed, which comprehensively considers the stator cogging effect, iron core saturation and magnetic leakage between tooth tips and poles, and the optimal quasi-sinusoidal back EMF is obtained. The output torque of the motor is increased by 18.1% due to the interaction of quasi-sinusoidal current and quasi-sinusoidal back EMF. Finally, the correctness of the theoretical derivation is verified through finite element analysis and experiments, which provides technical support for the large-scale application of high reliability dual three-phase PMSM.
2022, 49(8):59-65.
DOI: 10.12177/emca.2022.073
Abstract:
The micro-motion positioning stage structure driven by high frequency response and short stroke voice coil motor is adopted, and the flexible spring is designed to provide sufficient stiffness for the system, and the straightness error compensation system of inkjet printing scanning axis is established. The mathematical model of voice coil motor direct-drive micro-motion positioning stage is analyzed, and the servo control method of this kind of motor is studied, and a position closed-loop controller based on PD control is proposed, which enhance the anti-interference ability of the system. The test results show that this method can meet the requirements of the straightness accuracy of the scanning axis of inkjet printing and has strong robustness.
The micro-motion positioning stage structure driven by high frequency response and short stroke voice coil motor is adopted, and the flexible spring is designed to provide sufficient stiffness for the system, and the straightness error compensation system of inkjet printing scanning axis is established. The mathematical model of voice coil motor direct-drive micro-motion positioning stage is analyzed, and the servo control method of this kind of motor is studied, and a position closed-loop controller based on PD control is proposed, which enhance the anti-interference ability of the system. The test results show that this method can meet the requirements of the straightness accuracy of the scanning axis of inkjet printing and has strong robustness.
11 Research on Reactive Power V-Curve of Doubly-Fed Generator Motor for Variable Speed Pumped Storage
2022, 49(8):66-72.
DOI: 10.12177/emca.2022.075
Abstract:
The doubly-fed generator motor for variable speed pumped storage can maintain the active power output and then make full use of the power margin to become a stable reactive power source, so that it can flexibly participate in system voltage and phase regulation. In order to study the reactive power characteristics of the doubly-fed generator motor, based on the analysis of the relationship among the electrical quantities of doubly-fed generator motor, the V-curve of the doubly-fed generator motor for variable speed pumped storage is established on the basis of the stator current-rotor current, which can simply reflect the reactive power characteristics of the doubly-fed generator motor. Then, the variation law of V-curve of doubly-fed generator motor under different working conditions is studied. Finally, the hardware-in-loop test based on RTLAB platform shows that the doubly-fed variable speed pumped storage unit has the reactive power characteristics similar to synchronous motors, and also proves the correctness and effectiveness of the proposed analysis method.
The doubly-fed generator motor for variable speed pumped storage can maintain the active power output and then make full use of the power margin to become a stable reactive power source, so that it can flexibly participate in system voltage and phase regulation. In order to study the reactive power characteristics of the doubly-fed generator motor, based on the analysis of the relationship among the electrical quantities of doubly-fed generator motor, the V-curve of the doubly-fed generator motor for variable speed pumped storage is established on the basis of the stator current-rotor current, which can simply reflect the reactive power characteristics of the doubly-fed generator motor. Then, the variation law of V-curve of doubly-fed generator motor under different working conditions is studied. Finally, the hardware-in-loop test based on RTLAB platform shows that the doubly-fed variable speed pumped storage unit has the reactive power characteristics similar to synchronous motors, and also proves the correctness and effectiveness of the proposed analysis method.
2022, 49(8):73-78.
DOI: 10.12177/emca.2022.065
Abstract:
According to the attenuation effect of the traction network line boundary on high-frequency transient, a single-ended power direction protection method for the traction network of the through-type auto transformer (AT) in-phase traction power supply system based on fast ensemble empirical mode decomposition (FEEMD) and Teager energy operator (TEO) is proposed. Obtain the instantaneous power of the collected voltage and current signals when the fault occurs, and perform Teager transformation on the transient power to obtain the polarity of the TEO waveform mutation point as the direction criterion to determine whether it is a forward fault or a reverse fault. If it is a forward fault (inside or outside the opposite side), the fault transient current signal is decomposed by FEEMD, the intrinsic mode function 1 (IMF1) component of the fault signal is extracted, and then TEO is performed on the IMF1 component to obtain the instantaneous value of the TEO spectrum of the high-frequency transient current signal. The absolute pair value is obtained and summed, so as to judge whether the fault is inside or outside the opposite. Finally, the through-type AT in-phase traction power supply system model is built through PSCAD/EMTDC simulation software, and a large number of simulation data are extracted under different fault conditions. The simulation results show that this scheme can effectively partition internal and external faults and protect the full length of the traction network line.
According to the attenuation effect of the traction network line boundary on high-frequency transient, a single-ended power direction protection method for the traction network of the through-type auto transformer (AT) in-phase traction power supply system based on fast ensemble empirical mode decomposition (FEEMD) and Teager energy operator (TEO) is proposed. Obtain the instantaneous power of the collected voltage and current signals when the fault occurs, and perform Teager transformation on the transient power to obtain the polarity of the TEO waveform mutation point as the direction criterion to determine whether it is a forward fault or a reverse fault. If it is a forward fault (inside or outside the opposite side), the fault transient current signal is decomposed by FEEMD, the intrinsic mode function 1 (IMF1) component of the fault signal is extracted, and then TEO is performed on the IMF1 component to obtain the instantaneous value of the TEO spectrum of the high-frequency transient current signal. The absolute pair value is obtained and summed, so as to judge whether the fault is inside or outside the opposite. Finally, the through-type AT in-phase traction power supply system model is built through PSCAD/EMTDC simulation software, and a large number of simulation data are extracted under different fault conditions. The simulation results show that this scheme can effectively partition internal and external faults and protect the full length of the traction network line.
2022, 49(8):79-86.
DOI: 10.12177/emca.2022.076
Abstract:
Efficient and accurate shortterm power load forecasting plays an important role in the reliable operation and sustainable development of the power grid. In view of the complexity and timing characteristics of the factors that affect the changes in power grid load, and the shortcomings of the existing machine learning prediction methods in selecting key parameters based on experience, the convolutional neural network (CNN) is used to extract the multidimensional feature vector representing the load change, which is constructed as a time series and input to the gated recurrent unit (GRU), and the improved sparrow search algorithm (ISSA) is used to iteratively optimize the hyperparameters in the GRU network. The prediction experimental sample comes from the load data of a certain area in Yunnan, and the prediction accuracy of the proposed method reaches 98.624%. Compared with the neural network prediction methods of RNN, GRU and LSTM, the calculation example shows that the proposed method overcomes the difficulty of selecting key parameters based on experience and has higher prediction accuracy.
Efficient and accurate shortterm power load forecasting plays an important role in the reliable operation and sustainable development of the power grid. In view of the complexity and timing characteristics of the factors that affect the changes in power grid load, and the shortcomings of the existing machine learning prediction methods in selecting key parameters based on experience, the convolutional neural network (CNN) is used to extract the multidimensional feature vector representing the load change, which is constructed as a time series and input to the gated recurrent unit (GRU), and the improved sparrow search algorithm (ISSA) is used to iteratively optimize the hyperparameters in the GRU network. The prediction experimental sample comes from the load data of a certain area in Yunnan, and the prediction accuracy of the proposed method reaches 98.624%. Compared with the neural network prediction methods of RNN, GRU and LSTM, the calculation example shows that the proposed method overcomes the difficulty of selecting key parameters based on experience and has higher prediction accuracy.
2022, 49(8):87-92.
DOI: 10.12177/emca.2022.081
Abstract:
In view of the lack of research on the operation characteristics of large onshore doubly fed wind turbine during low voltage ride through (LVRT) and the lack of comparative verification of test and simulation, a GH Bladed simulation model is established for a MW-level onshore wind turbine to study the operation characteristics and load characteristics of key components during low voltage fault. At the same time, the actual type test data of the turbine are analyzed, and the specific LVRT conditions are simulated to compared and analyze the influence of the fault on the operation characteristics and the tower load. The simulation and test results show that the LVRT fault has an important impact on the tower load, and the impact is greater under strong wind conditions.
In view of the lack of research on the operation characteristics of large onshore doubly fed wind turbine during low voltage ride through (LVRT) and the lack of comparative verification of test and simulation, a GH Bladed simulation model is established for a MW-level onshore wind turbine to study the operation characteristics and load characteristics of key components during low voltage fault. At the same time, the actual type test data of the turbine are analyzed, and the specific LVRT conditions are simulated to compared and analyze the influence of the fault on the operation characteristics and the tower load. The simulation and test results show that the LVRT fault has an important impact on the tower load, and the impact is greater under strong wind conditions.
You are thevisitor
沪ICP备16038578号-3
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.
