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Volume 47,Issue 10,2020 Table of Contents
2020, 47(10):1-6.
DOI: 10.12177/emca.2020.114
Abstract:
When the switched reluctance motor (SRM) is running, the increased current caused by the increased load will lead the SRM to the magnetic saturation status. The traditional sensorless control method to solve the problem of magnetic saturation for SRM requires a lot of off-line measurements. So, a sensorless control strategy of SRM based on special position judgment is proposed, which obtains the full cycle inductance by injecting high frequency pulse voltage into the non-conducting phase. The unsaturated phase inductance values corresponding to four special positions at 15°, 30°, 45° and 60° are obtained on-line through the linear variation relationship of the unsaturated section of the inductance curve. According to the inductance-angle function, four special positions are obtained in one cycle. The motor speed and the full cycle rotor position are estimated by two adjacent positions. On this basis, a simulation model based on Simulink and an experimental platform with DSP are built, with which the correctness of the proposed method is verified.
When the switched reluctance motor (SRM) is running, the increased current caused by the increased load will lead the SRM to the magnetic saturation status. The traditional sensorless control method to solve the problem of magnetic saturation for SRM requires a lot of off-line measurements. So, a sensorless control strategy of SRM based on special position judgment is proposed, which obtains the full cycle inductance by injecting high frequency pulse voltage into the non-conducting phase. The unsaturated phase inductance values corresponding to four special positions at 15°, 30°, 45° and 60° are obtained on-line through the linear variation relationship of the unsaturated section of the inductance curve. According to the inductance-angle function, four special positions are obtained in one cycle. The motor speed and the full cycle rotor position are estimated by two adjacent positions. On this basis, a simulation model based on Simulink and an experimental platform with DSP are built, with which the correctness of the proposed method is verified.
2020, 47(10):7-16.
DOI: 10.12177/emca.2020.099
Abstract:
Simplified models to calculate the change of torque and flux of surface permanent magnet synchronous motor (PMSM) on stator flux coordinate system are proposed. In order to solve the problem of high torque ripple in direct torque control (DTC) system, dead-beat (DB) control of flux and torque is proposed. The calculation of ideal voltage vector for the DB control of flux and torque using simplified models is given and model predictive control (MPC) is used to implement the DB control. In order to improve the control performance of the system, the method to extend voltage vectors set is proposed, which can increase the number of candidate voltage vectors from 7 to 37. According to the angle of ideal voltage vectors, extended voltage vectors set does not add calculation burden. Look-up table is used to output voltage vector instead of space vector modulation (SVM) to improve the real-time performance. Simulation results show that extended voltage vectors set can decrease torque ripple. In order to further suppress flux and torque ripple, a novel method to expand voltage vectors is proposed. The angle and amplitude of ideal voltage vector are used to evaluate the angle and amplitude of the output voltage vector and look-up table is still used to output voltage vector with arbitrary value. Simulation results show that the novel method can effectively decrease flux and torque ripple.
Simplified models to calculate the change of torque and flux of surface permanent magnet synchronous motor (PMSM) on stator flux coordinate system are proposed. In order to solve the problem of high torque ripple in direct torque control (DTC) system, dead-beat (DB) control of flux and torque is proposed. The calculation of ideal voltage vector for the DB control of flux and torque using simplified models is given and model predictive control (MPC) is used to implement the DB control. In order to improve the control performance of the system, the method to extend voltage vectors set is proposed, which can increase the number of candidate voltage vectors from 7 to 37. According to the angle of ideal voltage vectors, extended voltage vectors set does not add calculation burden. Look-up table is used to output voltage vector instead of space vector modulation (SVM) to improve the real-time performance. Simulation results show that extended voltage vectors set can decrease torque ripple. In order to further suppress flux and torque ripple, a novel method to expand voltage vectors is proposed. The angle and amplitude of ideal voltage vector are used to evaluate the angle and amplitude of the output voltage vector and look-up table is still used to output voltage vector with arbitrary value. Simulation results show that the novel method can effectively decrease flux and torque ripple.
2020, 47(10):17-23.
DOI: 10.12177/emca.2020.113
Abstract:
Traditional PI speed control and traditional sliding mode control (SMC) lead to poor speed regulation during the surface permanent magnet synchronous motor (SPMSM) operation. When the load changes and the speed changes suddenly, traditional controllers cannot well control the system and the chattering is large. To solve these problems, a new non-singular fast terminal (NSFT) sliding mode surface combined with fuzzy control is proposed to design the speed controller, which can realize SPMSM speed sensorless control. Using the continuous function υ(s) to replace the switching function in the approaching law can effectively suppress chattering. The newly designed fuzzy control rules and fuzzy parameter adaptation law can adaptively adjust the parameters in the approaching law. Meanwhile, a Lyapunov function is designed to prove the stability of the new SMC controller. The simulation results of MATLAB show that the designed NSFT-fuzzy-SMC controller has faster adjustment speed and better adjustment effect when the system state changes, the system is more robust, and the chattering is smaller during stable operation. Compared with the general SMC, it has better control performance and anti-disturbance ability.
Traditional PI speed control and traditional sliding mode control (SMC) lead to poor speed regulation during the surface permanent magnet synchronous motor (SPMSM) operation. When the load changes and the speed changes suddenly, traditional controllers cannot well control the system and the chattering is large. To solve these problems, a new non-singular fast terminal (NSFT) sliding mode surface combined with fuzzy control is proposed to design the speed controller, which can realize SPMSM speed sensorless control. Using the continuous function υ(s) to replace the switching function in the approaching law can effectively suppress chattering. The newly designed fuzzy control rules and fuzzy parameter adaptation law can adaptively adjust the parameters in the approaching law. Meanwhile, a Lyapunov function is designed to prove the stability of the new SMC controller. The simulation results of MATLAB show that the designed NSFT-fuzzy-SMC controller has faster adjustment speed and better adjustment effect when the system state changes, the system is more robust, and the chattering is smaller during stable operation. Compared with the general SMC, it has better control performance and anti-disturbance ability.
2020, 47(10):24-32.
DOI: 10.12177/emca.2020.117
Abstract:
Position sensorless control is an important guarantee for the reliability of marine electric propulsion system. There is no single algorithm that can realize sensorless control in the whole speed range at present. In view of this fact， a novel position sensorless hybrid control strategy based on active disturbance rejection control (ADRC) is proposed. High frequency current injection method is used to estimate the rotor position in zero and low speed regions. In medium and high speed regions, the extended back electromotive force (EMF) method is used to estimate the rotor position. The two estimation schemes are integrated into the control structure, the ADRC controllers for the inner current loop are designed respectively, and the extended state observer is used to achieve high performance position estimation. Finally, a fusion-transition scheme is proposed to solve the problem of switching between the two algorithms. The physical platform experiment verifies the accuracy and strong robustness of the algorithm, which provides a basis for the realization of position sensorless control of interior permanent magnet synchronous motor (IPMSM) in the whole speed range.
Position sensorless control is an important guarantee for the reliability of marine electric propulsion system. There is no single algorithm that can realize sensorless control in the whole speed range at present. In view of this fact， a novel position sensorless hybrid control strategy based on active disturbance rejection control (ADRC) is proposed. High frequency current injection method is used to estimate the rotor position in zero and low speed regions. In medium and high speed regions, the extended back electromotive force (EMF) method is used to estimate the rotor position. The two estimation schemes are integrated into the control structure, the ADRC controllers for the inner current loop are designed respectively, and the extended state observer is used to achieve high performance position estimation. Finally, a fusion-transition scheme is proposed to solve the problem of switching between the two algorithms. The physical platform experiment verifies the accuracy and strong robustness of the algorithm, which provides a basis for the realization of position sensorless control of interior permanent magnet synchronous motor (IPMSM) in the whole speed range.
2020, 47(10):33-39.
DOI: 10.12177/emca.2020.111
Abstract:
In order to improve the system′s robustness to unknown disturbances and parameter changes, the active disturbance rejection control (ADRC) strategy is introduced into the permanent magnet synchronous motor (PMSM) position servo system, and the ADRC strategy is improved to make the system meet the requirements of high servo control performance. By improving the structure of the extended state observer (ESO) in ADRC, the observation speed of observer is increased. At the same time, in view of the error between the actual moment of inertia and the inertia used in ADRC, which affects the selection of the control gain in the speed ADRC controller, an online inertia identification method is adopted to adjust the controller parameter in real time. Based on the above two improvement measures, the improved ADRC controllers for the speed and position loops are designed, fundamentally improving the dynamic performance and antidisturbance capability of the system. Finally, the effectiveness of the improved ADRC strategy in the PMSM position servo system is verified by simulation.
In order to improve the system′s robustness to unknown disturbances and parameter changes, the active disturbance rejection control (ADRC) strategy is introduced into the permanent magnet synchronous motor (PMSM) position servo system, and the ADRC strategy is improved to make the system meet the requirements of high servo control performance. By improving the structure of the extended state observer (ESO) in ADRC, the observation speed of observer is increased. At the same time, in view of the error between the actual moment of inertia and the inertia used in ADRC, which affects the selection of the control gain in the speed ADRC controller, an online inertia identification method is adopted to adjust the controller parameter in real time. Based on the above two improvement measures, the improved ADRC controllers for the speed and position loops are designed, fundamentally improving the dynamic performance and antidisturbance capability of the system. Finally, the effectiveness of the improved ADRC strategy in the PMSM position servo system is verified by simulation.
2020, 47(10):40-45.
DOI: 10.12177/emca.2020.126
Abstract:
With the change of servo system parameters, the performance of the speed controller in the servo motor drive decreases. Aiming at this problem, a speed adaptive control method based on parameter identification is proposed. For the change of inertia, the model reference adaptive system (MRAS) is established in the continuous domain, and a proportional integral (PI) adaptive law is designed based on Popov hyperstability theory, which improves the convergence speed and steady-state accuracy of inertia identification. For load torque, a disturbance observer based on intermediate variable design is proposed. The identified values are fed back to the speed controller to realize on-line self-tuning of controller parameters. The experimental results show that the proposed method can accurately identify the moment of inertia and load torque for parameter adjustment of the controller and improve the controller′s robustness to parameter change.
With the change of servo system parameters, the performance of the speed controller in the servo motor drive decreases. Aiming at this problem, a speed adaptive control method based on parameter identification is proposed. For the change of inertia, the model reference adaptive system (MRAS) is established in the continuous domain, and a proportional integral (PI) adaptive law is designed based on Popov hyperstability theory, which improves the convergence speed and steady-state accuracy of inertia identification. For load torque, a disturbance observer based on intermediate variable design is proposed. The identified values are fed back to the speed controller to realize on-line self-tuning of controller parameters. The experimental results show that the proposed method can accurately identify the moment of inertia and load torque for parameter adjustment of the controller and improve the controller′s robustness to parameter change.
2020, 47(10):46-50.
DOI: 10.12177/emca.2020.108
Abstract:
The highfrequency AC current in the winding of intelligent stator cage multiphase motor leads to the eddy current, proximity effect and skin effect. The influence of different factors on the AC loss is investigated. A finite element software is used to establish the model of the motor and analyze the proximity effect and skin effect of the winding. The influences of the slot size, conductor position and crosssectional area on the AC loss are investigated. The AC loss of different pole pairs and materials is studied. The obtained results show that the AC loss can be reduced by changing the slot size, conductor crosssectional area and winding material.
The highfrequency AC current in the winding of intelligent stator cage multiphase motor leads to the eddy current, proximity effect and skin effect. The influence of different factors on the AC loss is investigated. A finite element software is used to establish the model of the motor and analyze the proximity effect and skin effect of the winding. The influences of the slot size, conductor position and crosssectional area on the AC loss are investigated. The AC loss of different pole pairs and materials is studied. The obtained results show that the AC loss can be reduced by changing the slot size, conductor crosssectional area and winding material.
2020, 47(10):51-55.
DOI: 10.12177/emca.2020.127
Abstract:
Taking a 72-slot 6-pole interior variable frequency adjustable speed permanent magnet synchronous motor (VFAS-PMSM) as an example，the numerical method and finite element simulation analysis are used to compare the influence of different rotor topologies on the electromagnetic performance of the motor from the aspects of no-load back electromotive force, harmonic content, cogging torque fluctuation and loss. In addition, the influence of radial electromagnetic force on the stress of the rotor is considered. The stress and deformation of the rotor core are simulated by numerical analysis and electromagnetic-structural statics coupling. Through the prototype test, the comparison and analysis method of the rotor topological structure of the interior VFAS-PMSM is proved to be of certain guiding significance.
Taking a 72-slot 6-pole interior variable frequency adjustable speed permanent magnet synchronous motor (VFAS-PMSM) as an example，the numerical method and finite element simulation analysis are used to compare the influence of different rotor topologies on the electromagnetic performance of the motor from the aspects of no-load back electromotive force, harmonic content, cogging torque fluctuation and loss. In addition, the influence of radial electromagnetic force on the stress of the rotor is considered. The stress and deformation of the rotor core are simulated by numerical analysis and electromagnetic-structural statics coupling. Through the prototype test, the comparison and analysis method of the rotor topological structure of the interior VFAS-PMSM is proved to be of certain guiding significance.
2020, 47(10):56-60.
DOI: 10.12177/emca.2020.120
Abstract:
The development of asynchronous traction motor for FXD1 power concentrated electric multiple unit（EMU） is introduced. The overall technical requirements of locomotive, motor structure design, motor electromagnetic design, motor characteristics, key technologies, and motor test are discussed. According to the technical characteristics of asynchronous traction motor, a prototype asynchronous traction motor is developed based on the research of key technical problems such as electromagnetic design, structure design and cooling design. The test results show that the asynchronous traction motor meets the technical requirements of locomotive，and verify the feasibility of the design scheme.
The development of asynchronous traction motor for FXD1 power concentrated electric multiple unit（EMU） is introduced. The overall technical requirements of locomotive, motor structure design, motor electromagnetic design, motor characteristics, key technologies, and motor test are discussed. According to the technical characteristics of asynchronous traction motor, a prototype asynchronous traction motor is developed based on the research of key technical problems such as electromagnetic design, structure design and cooling design. The test results show that the asynchronous traction motor meets the technical requirements of locomotive，and verify the feasibility of the design scheme.
2020, 47(10):61-67.
DOI: 10.12177/emca.2020.118
Abstract:
High-speed motors have the features of high current frequency, large stator core loss and large rotor eddy loss. The influential factors of core loss and rotor eddy loss are analyzed for the 10 kW, 100 000 r/min high-speed permanent magnet (PM) motor used in air compressor by comparing the effects of different magnetization methods (parallel and radial) and drive modes [driving by pulse amplitude modulation (PAM) square wave and SiC based pulse width modulation (PWM) sine wave]. Finite element analysis results indicate that the air gap flux harmonics of parallel magnetization are smaller, resulting in 40% smaller stator core loss compared with radial magnetization. Drive mode has a significant effect on motor losses especially on rotor loss. The rotor loss driving by sine wave is almost negligible, while it reaches 20% of the total losses when PM moter is driven by square wave because of the current harmonics. For the high rotor loss caused by square wave drive, further analysis is done by adding a copper shield on the rotor surface which can effectively reduce the eddy current loss. A high-speed motor with compressor load is tested under the control by two kinds of drivers to test the input active power on the DC bus. The results verify the influence of drive mode on motor losses.
High-speed motors have the features of high current frequency, large stator core loss and large rotor eddy loss. The influential factors of core loss and rotor eddy loss are analyzed for the 10 kW, 100 000 r/min high-speed permanent magnet (PM) motor used in air compressor by comparing the effects of different magnetization methods (parallel and radial) and drive modes [driving by pulse amplitude modulation (PAM) square wave and SiC based pulse width modulation (PWM) sine wave]. Finite element analysis results indicate that the air gap flux harmonics of parallel magnetization are smaller, resulting in 40% smaller stator core loss compared with radial magnetization. Drive mode has a significant effect on motor losses especially on rotor loss. The rotor loss driving by sine wave is almost negligible, while it reaches 20% of the total losses when PM moter is driven by square wave because of the current harmonics. For the high rotor loss caused by square wave drive, further analysis is done by adding a copper shield on the rotor surface which can effectively reduce the eddy current loss. A high-speed motor with compressor load is tested under the control by two kinds of drivers to test the input active power on the DC bus. The results verify the influence of drive mode on motor losses.
2020, 47(10):68-73，84.
DOI: 10.12177/emca.2020.116
Abstract:
Application of Copper-Aluminum Hybrid Rotor in Ultra-High Efficiency Motor
Application of Copper-Aluminum Hybrid Rotor in Ultra-High Efficiency Motor
2020, 47(10):74-79，109.
DOI: 10.12177/emca.2020.119
Abstract:
The principles, schemes and production balance of motor shaft production line design during the implementation of intelligent motor manufacturing are introduced. The advantages and disadvantages of U-shaped and linear arrangements of motor shaft production line are analyzed. The data collection and information interaction in the workshop where the production line is located in are introduced. These can provide a reference for the planning of shaft processing production lines in the motor industry. After the renovation of the project, the required production equipment is decreased by 29%, the number of employees is decreased by 77%, the production efficiency is increased by 35%, and the defective rate is decreased from 2.5% to 0.25%, improving the quality conformance of products.
The principles, schemes and production balance of motor shaft production line design during the implementation of intelligent motor manufacturing are introduced. The advantages and disadvantages of U-shaped and linear arrangements of motor shaft production line are analyzed. The data collection and information interaction in the workshop where the production line is located in are introduced. These can provide a reference for the planning of shaft processing production lines in the motor industry. After the renovation of the project, the required production equipment is decreased by 29%, the number of employees is decreased by 77%, the production efficiency is increased by 35%, and the defective rate is decreased from 2.5% to 0.25%, improving the quality conformance of products.
13 Structural Optimization of Motor Controller in Electric Vehicle Aiming at High-Power Chips Cooling
2020, 47(10):80-84.
DOI: 10.12177/emca.2020.100
Abstract:
Due to the compact layout, the design space for motor controller in electric vehicle is limited. Besides, fan cooling is forbidden in some cases to ensure the reliability of the motor controller and the highpower chips. In order to decrease the temperature of highpower chips in motor controller, structural optimizations are carried out. Firstly, layout of the chips is rearranged to change the surrounding flow field. Secondly, structure of the printed circuit board (PCB) is changed to alter the flow field. Finally, the cold end heat conduction structure is used to cool the chips. The optimization measures are verified by simulation. The optimization results can provide theoretical guidance for the heat dissipation design of the motor controller.
Due to the compact layout, the design space for motor controller in electric vehicle is limited. Besides, fan cooling is forbidden in some cases to ensure the reliability of the motor controller and the highpower chips. In order to decrease the temperature of highpower chips in motor controller, structural optimizations are carried out. Firstly, layout of the chips is rearranged to change the surrounding flow field. Secondly, structure of the printed circuit board (PCB) is changed to alter the flow field. Finally, the cold end heat conduction structure is used to cool the chips. The optimization measures are verified by simulation. The optimization results can provide theoretical guidance for the heat dissipation design of the motor controller.
2020, 47(10):85-91.
DOI: 10.12177/emca.2020.112
Abstract:
A high power density dual-drive controller is developed to meet the requirements of electromechanical coupling system of novel hybrid electric vehicles. The structure design scheme of the controller is described in detail, and the hardware electrical principle and software control strategy are briefly introduced. The cascaded seven-channel cooling design scheme is proposed, and the heat dissipation effect of dual-drive controller is studied by finite element simulation. Finally, the bench test of the dual-drive motor controller is carried out with a prototype controller. The test results show that the dual-drive motor controller has a high-efficiency cooling effect and stable control performances.
A high power density dual-drive controller is developed to meet the requirements of electromechanical coupling system of novel hybrid electric vehicles. The structure design scheme of the controller is described in detail, and the hardware electrical principle and software control strategy are briefly introduced. The cascaded seven-channel cooling design scheme is proposed, and the heat dissipation effect of dual-drive controller is studied by finite element simulation. Finally, the bench test of the dual-drive motor controller is carried out with a prototype controller. The test results show that the dual-drive motor controller has a high-efficiency cooling effect and stable control performances.
15 Emulator for Dual Three-Phase Permanent Magnet Synchronous Motor Based on Power Electronic Converter
2020, 47(10):92-96.
DOI: 10.12177/emca.2020.104
Abstract:
The electric power steering (EPS) system is the core component of the car. The use of power hardware-in-the-loop simulation test technology can shorten the system development time, reduce the development cost, and reduce the development risk, so it has become a very important part of the development process. A dual three-phase permanent magnet synchronous motor (PMSM) with a phase shift of 30° is used as the research object, and a motor emulator scheme based on a power electronic converter is proposed to simulate the dynamic and static electrical behaviors of the motor under different load conditions. It provides an efficient platform for the control algorithm development and fault simulation tests of EPS system. Simulation results verify the effectiveness and feasibility of the proposed scheme.
The electric power steering (EPS) system is the core component of the car. The use of power hardware-in-the-loop simulation test technology can shorten the system development time, reduce the development cost, and reduce the development risk, so it has become a very important part of the development process. A dual three-phase permanent magnet synchronous motor (PMSM) with a phase shift of 30° is used as the research object, and a motor emulator scheme based on a power electronic converter is proposed to simulate the dynamic and static electrical behaviors of the motor under different load conditions. It provides an efficient platform for the control algorithm development and fault simulation tests of EPS system. Simulation results verify the effectiveness and feasibility of the proposed scheme.
2020, 47(10):97-102.
DOI: 10.12177/emca.2020.107
Abstract:
The new energy vehicle (NEV) motor has strict performance requirements for such parameters as torque density, power density, torque ripple, vibration noise and high efficiency section. Rotor topology and its structural parameters directly affect the magnetic flux density, magnetic field distribution and harmonic magnetic field contents, so they play an important role in the performance of NEV motor. For NEV motor, there are different operating conditions and various performance parameters. Finite element software is used to build the electromagnetic field calculation model for the main operating conditions and determine the structural parameters to be optimized. According to the main performance of vehicle motor, the optimization objective is defined with torque ripple, cogging torque, airgap induced voltage total harmonic distortion (THD) and output torque. The objective function is defined according to the performance requirements of different working conditions, and the genetic algorithm is selected as the multiobjective optimization design algorithm. According to the optimized calculation results, the scheme selection is outlined. Finally, the optimal structure and size parameters of the rotor are determined. The optimization design method can quickly determine the optimal electromagnetic design scheme of vehicle permanent magnet motor and enrich the efficient optimization design approaches of this kind of motor.
The new energy vehicle (NEV) motor has strict performance requirements for such parameters as torque density, power density, torque ripple, vibration noise and high efficiency section. Rotor topology and its structural parameters directly affect the magnetic flux density, magnetic field distribution and harmonic magnetic field contents, so they play an important role in the performance of NEV motor. For NEV motor, there are different operating conditions and various performance parameters. Finite element software is used to build the electromagnetic field calculation model for the main operating conditions and determine the structural parameters to be optimized. According to the main performance of vehicle motor, the optimization objective is defined with torque ripple, cogging torque, airgap induced voltage total harmonic distortion (THD) and output torque. The objective function is defined according to the performance requirements of different working conditions, and the genetic algorithm is selected as the multiobjective optimization design algorithm. According to the optimized calculation results, the scheme selection is outlined. Finally, the optimal structure and size parameters of the rotor are determined. The optimization design method can quickly determine the optimal electromagnetic design scheme of vehicle permanent magnet motor and enrich the efficient optimization design approaches of this kind of motor.
2020, 47(10):103-106，109.
DOI: 10.12177/emca.2020.122
Abstract:
An inverter control strategy based on current delay compensation is studied for the three-level inverter grid connection system. Firstly, according to the topology of the three-level inverter grid connection system, an improved space vector modulation strategy is studied, which can effectively reduce the common mode voltage. Then, the active damping control method based on capacitive current feedback and the current half-cycle control strategy based on compensation delay are studied. The analysis shows that the half-cycle control strategy can avoid impedance polarity jump and improve the stability of the system. Finally, the effectiveness of the method is verified by simulation and experiment.
An inverter control strategy based on current delay compensation is studied for the three-level inverter grid connection system. Firstly, according to the topology of the three-level inverter grid connection system, an improved space vector modulation strategy is studied, which can effectively reduce the common mode voltage. Then, the active damping control method based on capacitive current feedback and the current half-cycle control strategy based on compensation delay are studied. The analysis shows that the half-cycle control strategy can avoid impedance polarity jump and improve the stability of the system. Finally, the effectiveness of the method is verified by simulation and experiment.
2020, 47(10):107-109.
DOI: 10.12177/emca.2020.115
Abstract:
Rotor in squirrel-cage induction motor has direct effect on the motor performance. Vertical die casting process is one of the common techniques to produce industrial motors. The key to manufacture qualified industrial rotors smoothly depends on the casting cup and the precise temperature control in the process. A die casting melting cup without asbestos for vertical motor rotor production is designed. With this technology, no asbestos will be pressed and mixed into rotors. Meanwhile, using high pressure die casting equipment, the rotor quality can be improved effectively to satisfy the performance requirements of ultra high efficiency motor.
Rotor in squirrel-cage induction motor has direct effect on the motor performance. Vertical die casting process is one of the common techniques to produce industrial motors. The key to manufacture qualified industrial rotors smoothly depends on the casting cup and the precise temperature control in the process. A die casting melting cup without asbestos for vertical motor rotor production is designed. With this technology, no asbestos will be pressed and mixed into rotors. Meanwhile, using high pressure die casting equipment, the rotor quality can be improved effectively to satisfy the performance requirements of ultra high efficiency motor.
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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.
