Research of Three Phase PWM Rectifier based on Direct Vector Control Method

In oilfield worldwide, beam pumping units are wildly used to produce oil. the working mechanism of beam pumping unit determines that its driving motor frequently enters into the state of power generation, so PWM reversible rectifier is an ideal choice for recycle the generated energy, therefore it is necessary to research the control theory of PWM reversible rectifier. The paper presents a digital algorithm for the PWM rectifier, on the basis of coordinate analyzing theory and SVPWM method. The method that directly calculates the basic vector operation time and position is adopted, so the arc-tangent calculation is avoided, calculation process is simplified. Based on the vector coordinate transformation of three-phase reversible PWM rectifier, the control equation of direct current control method is derived in this paper. The rectifier control algorithm is realized with high performance DSP TMS320F28335. The experimental results prove that the method proposed in the paper is practical and correct.