• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.5
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• pp.462-473
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• 1999

This paper addresses the current measurement issue of all digital field oriented control of ac motors. The p paper focuses on the effect of low-pass filter and also on the sampling of the fundamental component of the m motor current. The low-pass filter, which suppresses the switching noise of the motor current, introduces v variable phase delay according to the current ripple frequency. It is shown that the current sampling error c consists of the fundamental component and high frL'quency ripple components. In this paper, the dependency of t this current sampling e$\pi$or on the reference voltage vector is investigated analytically and a sampling technique i is proposed to minimize the error. The work is based on the three phase symmetry pulse width modulation l inverter driving an induction machine. With this technique, the bandwidth of current regulator can be extended t to the limit given by the switching frequency of the inverter and more precise torque regulation is possible.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.1
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• pp.89-97
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• 2007

This paper describes a load simulator with power recovery capability, which is based on the voltage source converter-inverter set. The load simulator can save the electric energy that should be consumed to test the operation and performance of the power quality compensator and the power equipment. The load simulator consists of a converter-inverter set with a DSP controller for system control and PWM pulse generation. The converter operates as a universal load to model the linear load and the non-linear load, while the inverter feed the energy back to the power source with harmonic compensation. the performance of proposed load simulator was analyzed with scaled-model experiment, interconnected with the active power filter. The experimental results confirms that the proposed load simulator can be utilized to test the performance of active power filter.