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Hung-Chi Chen
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ABSTRACT: In this paper, a novel duty phase control (DPC) for single-phase boost-type switching-mode-rectifier (SMR) is developed and digitally implemented in DSP-based system. Compared to the conventional multiloop control structure with inner current loop and outer voltage loop, it is noted that there is only one voltage loop tuning the phase of predefined duty pattern (i.e. duty phase) in the proposed DPC. Due to no current loop, sampling inductor current and tracking current are unnecessary when SMRs are operated to shape the current waveform and regulate the output voltage. It implies that the single-loop DPC is simple and adaptable to the implementation with digital and analog integrated circuits. In this paper, first, the effect of the duty phase on the input current is analyzed and modeled. It shows that the sinusoidal current waveform can be naturally generated by the predefined duty pattern and the current amplitude is roughly proportional to the controllable duty phase. Then, a voltage controller is designed to regulate the dc output voltage by tuning this duty phase. Finally, some simulated and experimental results have been given to illustrate the performances of the proposed DPC.
IEEE Transactions on Power Electronics 08/2008; · 4.65 Impact Factor
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ABSTRACT: For a switch-mode rectifier (SMR), the inherent existence of a double frequency output voltage ripple renders the contradiction between the input current waveform and voltage regulation control performances. In this paper, the approaches for the ripple compensation and the improvement of input current waveform control of SMR are presented. First, a robust ripple compensation controller is developed, such that the effect of double frequency ripple contaminated in the output voltage feedback signal can be cancelled as far as possible. It follows that the current command yielded by the voltage control loop will be nearly ripple-free. Then a current control scheme, which consists of a feedback controller, a command feedforward controller and a robust disturbance feedforward controller, is proposed to let the SMR possess improved robust input current waveform control performance. Theoretical basis, design and implementation of the proposed controllers are described in detail. All the designed controllers are carried out digitally using DSP TMS320C240. The measured results indicate that under well-regulated dc output voltage, improved input current waveforms with high power quality are obtained by the proposed control approach, and the results are rather insensitive to input voltage and load variations.
IEEE Transactions on Power Electronics 04/2004; · 4.65 Impact Factor
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ABSTRACT: The winding current response speed and the adequate commutation significantly affect the control performance of a sensorless brushless dc motor (BDCM) drive. In this paper, the studies about these two issues to enhance the performance of BDCM drive are made. First, the sensorless inverter-fed BDCM drive with a proposed current command generation scheme is established. An intelligent commutation instant tuning technique is developed to pursue better motor torque generating characteristics. For achieving this goal, the motor drawn line current minimization is employed as the performance index in making the commutation tuning. After generating the current command with adequate commutation, a robust current-mode controller is further developed and applied to greatly speed up the square wave current tracking response and the response is rather insensitive to the machine parameter and back electromotive force (back-EMF) changes. In Addition, a simple starting method and a speed estimation approach are also proposed. Some experimental results are provided to demonstrate the validity of the proposed control method.
IEEE Transactions on Power Electronics 10/2002; · 4.65 Impact Factor
