Jae-Woo Jung

Thermal Analysis of Water Cooled ISG Based on a Thermal Equivalent Circuit Network

Recently, the interior permanent synchronous motor (IPMSM) has been applied to an integrated starter and generator (ISG) for hybrid electric vehicles. In the design of such a motor, thermal analysis is necessary to maximize the power density because the loss is proportional to the power of a motor. Therefore, a cooling device as a heat sink is required internally. Generally, a cooling system designed with a water jacket structure is widely used for electric motors because it has advantages of simple structure and cooling effectiveness. An effective approach to analyze an electric machine with a water jacket is a thermal equivalent network. This network is composed of thermal resistance, a heat source, and thermal capacitance that consider the conduction, convection, and radiation. In particular, modeling of the cooling channel in a network is challenging owing to the flow of the coolant. In this paper, temperature prediction using a thermal equivalent network is performed in an ISG that has a water cooled system. Then, an experiment is conducted to verify the thermal equivalent network.

Inductance Measurement of Interior Permanent Magnet Synchronous Motor in Stationary Frame of Reference

An inductance measurement method for interior permanent magnet synchronous machine (IPMSM) is proposed in this paper. In this method, the motor is measured at standstill condition, and only a 3-phase voltage source, an oscilloscope and a DC voltage source are required. Depending on the deductive dq-axis voltage equations in the stationary frame of reference, the dq-axis inductances at different current magnitude and vector angle can be calculated by the measured 3-phase voltages and currents. And hence, the saturation and crossmagnetizing effect of the inductances are measurable. This paper introduces the principle equations, experiment setup, data processing, and results comparison on the concentrated-winding and distributed-winding IPMSMs.

Design Technique of Magnetic Suspension for Vibration Free Table

This paper proposes the design method of a magnetic suspension that is controlled actively on the exterior vibrations by low frequencies. The magnetic suspension is able to compensate the vibrations with individual controls unlike a mechanical suspension. In the magnetic suspension, two characteristics are required. That is, firstly, magnetic motive force (MMF) by armature winding must be increased linearly. Lastly, the other is same output force as direction of MMF. In this paper, response surface method combined with experimental design is applied to invested the characteristics and optimize the magnetic suspension for vibration free table

The Comparison Study of Distributed and Concentrated Winding Types in Interior Permanent Magnet Motor for Integrated Starter Generator

In this paper, distributed and concentrated winding type interior permanent magnet synchronous machines are designed and compared to use for an integrated starter generator. The characteristics are computed from equivalent circuit which consists of parameters obtained from finite element analysis. The comparison results are discussed, and the determined model is fabricated and tested