• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.2
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• pp.175-180
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• 2017

The measurement of three-phase current is important to control the instantaneous torque of a interior permanent magnet synchronous motor(IPMSM) using a three-phase inverter. Therefore, shunt resistors are used in low-cost motor-driving systems to measure three-phase current instead of additional current sensors that are too expensive for these systems. However, in certain regions of a space vector plane, shunt resistors cannot reconstruct three-phase current in high-speed driving mode. In this paper, predictive current control is used to compensate for the three-phase current in those regions, which results in a reduction of current ripple in a three-shunt sensing inverter(TSSI) and torque ripple in IPMSM.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1791-1801
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• 2016

This paper considers a carrier based signal injection method for use in the three shunt sensing inverter (TSSI) for sensorless motor control. It also analyzes the loss according to the injection axis of the voltage signal. To remove both the phase current and rotor position sensors, a sensorless method and a phase current reconstruction method can be simultaneously considered. However, an interaction between the two methods can be incurred when both methods inject voltage signals simultaneously. In this paper, a signal injection based sensorless method with the 120° OFF Discontinuous PWM (DPWM) is implemented in a TSSI to avoid this interaction problem. Since one leg does not have a switching event for one sampling period in the 120° OFF DPWM, the switching loss is altered according to the injection axis. The switching loss in the d-axis injection case can be up to 32% larger than that in the q-axis injection case. Other losses according to the injection axis are also analyzed.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.99-100
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• 2016

In a AC motor used by three phase inverter, the phase current must be measured to control instantaneous torque. It is expensive to use current sensor for measuring current in low cost motor. So, shunt resistor is used to measure current. But, the method sensing the phase current using shunt resistor cannot perform the vector control in high speed because of the area that impossible to restore three phase current. In this paper, predictive current is proposed for reconstructing the current in the impossible current sensing area that reduce the current ripple in TSSI(Three shunt sensing inverter) for PMSM.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.224-225
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• 2016

매입형 영구자석 전동기에 가격과 부피를 줄이기 위해 3개의 션트 저항을 이용하는 인버터를 사용하였고 회전자 위치센서를 제거하기 위해 모델기반 센서리스 기법을 사용하였다. TSSI (Three Shunt current Sensing Inverter)의 문제점인 특정 전압 이상에서는 전류를 검출할 수 없는 영역이 생기게 된다. 이를 예측전류를 사용하여 전류복원 불가영역을 개선하였다.