Papers by Keyword: Fixed Switching Frequency

Abstract: In this paper, we study a modified predictive direct power control scheme (P-DPC).This scheme which based on model predictive control (MPC) uses a discrete rectifier model to infer the predictive direct power control theme again, and selects the operating time of voltage vector and voltage vector to realize fixed switching frequency through setting the minimum power errors of each sampling period. This control scheme has a lower switching frequency compared to MP-DPC; and it is still simple and clear implemented in the stationary reference frame directly, meanwhile, it does not need PI controllers or voltage-oriented controllers compared to other developed control schemes. We make simulations using MATLAB. The result show the excellence of this novel predictive direct power control scheme through improving the switching frequency, current THD and active power and reactive power quality compared to MP-DPC and LUT-DPC.

Abstract: This paper presents fixed switching frequency direct power control (FSF-DPC) for three-phase AC/DC converter. Sensorless control strategies based on virtual-flux can optimize the performance of the system. In this paper, realization of pulse width modulation method for FSF-DPC is presented. The simulation results show that the system running performance is good.

Abstract: In this paper, a constant switching frequency direct power control strategy based on the virtual line-flux-linkage oriented system for three-level PWM rectifier using space vector modulation (VF-DPC-SVM) is proposed, which is on the basis of the mathematic model of the PWM rectifier, the instantaneous reactive power and the vector control theory. Compared with the traditional control strategy, the proposed VF-DPC-SVM method guarantees a fixed switching frequency and realizes a better dynamic performance. The simulations and experiments indicate that the system has a better dynamic performance with lower harmonic current by use of the control strategy and can achieve the decoupling control of the active and reactive power.