Advances on Single-Phase Line-Start High Efficiency Interior Permanent Magnet Motors

Abstract

The past 25 years have been a significant period with advances in the development of interior permanent magnet (IPM) machines. Line-start small IPM synchronous motors have expanded their presence in the domestic marketplace from few specialized niche markets in high efficiency machine tools, household appliances, small utility motors, and servo drives to mass-produced applications. A closer examination reveals that several different knowledge-based technological advancements and market forces as well as consumer demand for high efficiency requirements have combined, sometimes in fortuitous ways, to accelerate the development of the improved new small energy efficient motors. This paper provides a broad explanation of the various factors that lead to the current state of the art of the single-phase interior permanent motor drive technology. A unified analysis of single-phase IPM motor that permits the determination of the steady-state, dynamic, and transient performances is presented. The mathematical model is based on both d-q axis theory and finite-element analysis. It leads to more accurate numerical results and meets the engineering requirements more satisfactorily than any other methods. Finally, some concluding comments and remarks are provided for efficiency improvement, manufacturing, and future research trends of line-start energy efficient permanent magnet synchronous motors. Index Terms-Dynamicoperation, fractional horsepower, high efficiency, improved performance, interior permanent magnet, line-start, small motors, steady state. NOMENCLATURE A Magnetic vector potential. A z Axial component of magnetic vector potential A. B o Friction coefficient. C r Running capacitor. C s Starting capacitor.

Losses Modeling of the Electric Vehicles Power Chain

“…The latter structure has the disadvantage of low switching frequency (Below 150 Hz) [5], But it is the cheapest and haven't the problem of the floating potential, since each inverter arm is controlled by a single electromagnet. As against the IGBT structure offers the possibility to achieve a switching frequency of 8000 Hz [6] which leads to a good quality of the dynamic characteristic of EVs, it raises a lot of disadvantages which can be made, as examples [9][10][11][12]:…”

“…This model relates both chain structures of power to the IGBT and the other electromagnetic switch (IE), in order to select the one with the lowest losses [9][10][11][12].…”

“…The structure of an IGBT inverter arm s is illustrated by the following figure [9][10][11][12]: The relationship of the conduction losses in the transistors is as follows: (1) Whereρ is the duty ratio of the control signals of the transistors, I m is the average current on a half period and V ce is the collector-emitter voltage.…”

“…The model of the power converter based on the comparison of the reference voltages (the voltage of the motor so that it can develop the necessary torque to the movement of EV), regulator outputs of the phase currents, to a triangular signal with f sw frequency less than the frequency of opening and closing of the electromagnetic switches relies [1][2][3][4][5][6][7][8][9][10][11][12]. (8) Where n q is the quality factor of supply voltages and f ie is the frequency of delay to the opening and closing of the electromagnetic switches:…”

Evaluation of the Efficiency of Line-Start Permanent-Magnet Machines as a Function of the Operating Temperature

“…As highefficiency line-start permanent-magnet motors (LSPMMs) have evolved from fractional horsepower single-phase motors [4] into commercial three-phase machines in a power range up to 7.5 kW [5]- [8], LSPMMs are being suggested as one of the possibilities to achieve IE4 efficiency. A state-of-the-art review of both practical advantages and limitations of these LSPMMs has been presented in [9].…”