Single-phase Line-start Permanent Magnet Research Articles

Steady State Analysis Of Single Phase IPM Motors By D-Q Harmonic Balance Method

A concise steady-state analysis of a single-phase line-start permanent magnet (SPLSPM) machine is conducted from a developed d-q model using the d-q harmonic balance technique. The d-q model was developed in rotor reference frame from a phase variable model of the machine. SPLSPM whose performance indices were characterized by high torque ripples has detailed analysis docile mostly in computer simulations quite unlike the three-phase types. The main cause is not far-fetched, it was due to nonexistence of precise mathematical model in d-q rotor frame of the motor due to the unbalanced field winding, the rotor saliency and the presence of the capacitor in the auxiliary windings. Even after model has been developed, the simple traditional procedure of setting all time varying component to zero for steady-state analysis fails because the rotor position dependence on the inductance expressions could not be eliminated. The d-q harmonic-balance technique was then applied. An important feature of the harmonic balance technique was that it decoupled all equations to simple sine waveforms in a style that resembled Fourier series. Results yield torque pulsation, current and load characteristics in the steady state.

단상 유도형 동기전동기의 회전자 설계에 관한 연구

The purpose of this paper is the rotor design of a single-phase LSPM(Line-start permanent magnet) motor. A single-phase LSPM motor has a permanent magnet in the rotor that is same as induction motor. For that reason, magnet is operated by breaking torque in starting region and alignment torque in driving region. Therefore, we need the design process considering the trade-off relationship.<BR> In this paper, we propose the design process of a single-phase LSPM motor for a high starting torque and efficiency with FEM. And we use Taguchi Method for considering tolerance in manufacture. Finally, we compared the LSPM motor that is designed in this paper and conventional induction motor.

Single-phase line start permanent magnet synchronous motor. Rotor construction and stator winding optimization

Abstract The paper deals with construction of single-phase line start permanent magnet synchronous motor. Circuit-field single-phase line start permanent magnet synchronous motor model based on the mass production single-phase induction motor was applied in Maxwell program. Various rotor constructions were taken into account. Influence of the rotor construction on the motor properties was examined. Running motor performances were examined.

Optimum Design of a Single-Phase Line-Start PM Motor Considering Efficiency, Maximum Torque, and Starting Torque

In this paper, an optimum design for a single-phase line start permanent magnet (LSPM) motor with respect to efficiency, maximum torque, and starting torque is proposed. The design variables, objective functions, and constraints are selected for this optimum design, which is divided into three steps. Step I maximizes the rated efficiency while maintaining a balanced operation and minimizing the stator copper loss. Step II utilizes equivalent circuit analysis to consider the efficiency and the maximum torque, while Step III calculates the precise starting torque using finite element (FE) analysis. The validity of the optimum design is verified by comparing the efficiency, maximum torque, and starting torque characteristics of the time-step FE analysis with experimental results.

Investigation on the performance of the single-phase LSPM motor for variable capacity type compressor

This paper investigates the performance of the line start permanent magnet (LSPM) motor which needs a high efficiency characteristic in a wide operation region. LSPM motor's performance indexes, such as efficiency, motor current, load angle and synchronous torque, have complex relationship with each other according to the main and auxiliary windings distribution, and the selection of running capacitor. The output characteristics can be defined by the winding structure which is calculated by d-q equivalent circuit and finite element method. The efficiency characteristic is verified by simulation as well as by experiment on the designed LSPM motor. From the results, we show that the redesigned model considering the winding structure and capacitor matching has a wide operating region.

Practical Optimum Design Based on Magnetic Balance and Copper Loss Minimization for a Single-Phase Line Start PM Motor

This paper introduces the condition of balanced operation to solve problems caused by an unbalanced magnetic field when a single-phase line start permanent magnet motor operates in steady-state. Using an equivalent circuit on the basis of symmetric field theory, conditions are found for balanced operation at rated conditions and for copper loss minimization in the stator. The initial model is modified applying these two conditions from commercial model. In addition, an optimum design is implemented in order to improve starting characteristic. In an optimum design process, the sampling points are chosen by latin hypercube sampling and from the results, an approximation model is made by the radial basis function. Then the optimization results are obtained by a genetic algorithm. The validity of the proposed design is verified by confirming the efficiency, torque ripple, ohmic loss of the rotor, and starting characteristic through time step FE-analysis and experimental results.

Analysis of non-linear effects on starting characteristics of a single-phase line start permanent magnet motor

Analysis of non-linear effects on starting characteristics of a single-phase line start permanent magnet motor

A Study on the Optimal Rotor Design of LSPM Considering the Starting Torque and Efficiency

This paper presents the optimal rotor design method in a single-phase line-start permanent magnet motor (LSPM) considering the starting torque and efficiency. To consider nonlinear characteristics, the design process is comprised of the FEM and analytical method. During this study, permanent-magnets and cage bars were designed using the magnetic equivalent circuit method and the barriers that control all magnetic flux were designed using the FEM, and the tradeoff of starting torque and efficiency is controlled by weight function in Taguchi method simulation. Finally, the performance of the optimal model is compared with those of conventional models.

A study on the irreversible magnet demagnetization in single-phase line-start permanent magnet motor

The large demagnetizing currents in a single-phase line-start permanent magnet motor are generated by a starting and locked rotor condition. Thus, irreversible magnet demagnetization occurs due to the external demagnetizing field by these currents. In this paper, we present the phenomenon of the irreversible magnet demagnetization using two-dimensional finite-element method (2-D FEM). The nonlinear analysis of a permanent magnet is added to 2-D FEM to consider irreversible demagnetization. As a result, design techniques which are effective in avoiding irreversible demagnetization are proposed.

단상 유도형 동기 전동기(LSPM)의 특성해석에 관한 연구

Electric motor efficient improvement from home appliance field is important to the effect reducing the energy consumption. But the electric motor design/analysis technology is still insufficient. Specially the electric motor design/analysis technology of satisfying characteristic of both the induction motor and the synchronous motor such as Line start permanent motor. Therefore the electric motor design/analysis technology is urgently demanded reliability. This paper proposes the sing1e-phase line-start permanent magnet motor to develop the motor it with be able to alternate the sing-phase induction motor it is a refrigerator compressor motor. The sing-phase induction motor is analyzed in the steady state. And we have a certification test to compare our single-phase line-start permanent magnet motor with the sing-phase induction motor. In order to improve the performance, the stator of the single-phase line-start permanent magnet motor is same as the stator of the sing-phase induction motor and changes the rotor form and has the permanent magnet. It used the Finite Element Method(FEM) which is widely used with electronic-magnetic field numerical analysis method.

Design of Single-Phase Line-Start Permanent Magnet Motor Using Equivalent Circuit Method

In this research, the design procedure and the design method of a single-phase line-start permanent magnet motor (LSPM) are proposed. In the design procedure, the permanent magnet is designed first and the windings and capacitors are designed later. As well, the points of design of each design parameter are explained. In the design of the single-phase LSPM, the equivalent circuit method is combined with the finite element method (FEM) because it has a shorter analysis time than FEM. The 400 watts single-phase LSPM is designed and manufactured. The characteristics of the manufactured single-phase LSPM are analyzed and experimented. From the analysis result and the experiment result, it is verified that the design procedure and the design method of the single-phase LSPM is valid.

A study on iron loss analysis method considering the harmonics of the flux density waveform using iron loss curves tested on epstein samples

This paper deals with a study on an iron loss analysis method in the single-phase line-start permanent magnet synchronous motor. The iron loss is affected by the time rate of the change of magnetic flux density at the motor cores. The distribution and changes in magnetic flux densities of the motor are computed by using a two-dimensional finite element method. Discrete Fourier Transform (DFT) is used to analyze the magnetic flux density waveforms in each element of the analysis model. Iron losses in each element are evaluated using iron loss curves tested by an Epstein test apparatus. The total iron loss can be obtained by the summation of the iron losses in all the elements.

Performance analysis of single-phase line-start permanent-magnet synchronous motor

Single-phase line-start permanent magnet (LSPM) synchronous motors have always been far less amenable to detailed computer-aided performance analysis compared with three-phase LSPM synchronous motors. The main reason is the lack of an accurate mathematical model of the motor characteristics arising from the unbalanced stator field and the rotor saliency. However, there is great potential for these types of motors to replace conventional single-phase induction motors in many domestic applications on account of their higher efficiencies when properly designed. In this paper, a new model that is applicable to both synchronous and asynchronous operation of the motor is proposed in which the parameters can be readily obtained by the two-dimensional (2-D) static finite-element method (FEM). It includes both the forward and backward rotating magnetic fields. It can be used to analyze the torque versus slip characteristics and predict the steady-state performances of the motor quickly with reasonable accuracy. The model has also been extended to simulate the transient start-up process and other dynamic performances. The models are suitable for the initial design and optimization of the motor geometry because of its low run-time overheads. Experimental results have verified the practicability of the models.

Performance Analysis of Single-Phase Line-Start Permanent Magnet Synchronous Motors

Single-phase line-start permanent magnet (LSPM) synchronous motors have always been far less amenable to detailed computer-aided performance analysis compared with three-phase LSPM synchronous motors. The main reason is the lack of an accurate mathematical model of the motor characteristics arising from the unbalanced stator field and the rotor saliency. However, there is great potential for these types of motors to replace conventional single-phase induction motors in many domestic applications on account of their higher efficiencies when properly designed. In this paper, a new model that is applicable to both synchronous and asynchronous operation of the motor is proposed in which the parameters can be readily obtained by the two-dimensional (2-D) static finite-element method (FEM). It includes both the forward and backward rotating magnetic fields. It can be used to analyze the torque versus slip characteristics and predict the steady-state performances of the motor quickly with reasonable accuracy. The model has also been extended to simulate the transient start-up process and other dynamic performances. The models are suitable for the initial design and optimization of the motor geometry because of its low run-time overheads. Experimental results have verified the practicability of the models.

Performance of skewed single-phase line-start permanent magnet motors

In this paper, the authors investigate the modeling of single-phase line-start permanent magnet motors using finite-element (FE) analysis. It is shown that FE modeling is capable of giving very accurate predictions when compared with test results, for both skewed and unskewed motors. The skewed motor is also modeled using an analytical method. The accuracy of the FE method is contrasted with that obtained using the analytical method.