PWM rectifier

About: PWM rectifier is a research topic. Over the lifetime, 2254 publications have been published within this topic receiving 25614 citations.

Constrained optimal direct power control of voltage-source PWM rectifiers

Abstract: The paper presents an online approach to the model-predictive control of the boost type PWM rectifier. The optimization is made on a horizon of one switching period for a cost function based on the instantaneous real and imaginary power errors. The control vectors are synthesized by space-vector modulation and are confined to the hexagonal area defined by the possible switching states of the three-phase bridge. The optimal control algorithm is developed in presence of the grid current limitation, introduced as a practical constraint.

Direct power control of PWM rectifier based on virtual flux

Abstract: Compared with VOC(Voltage-Oriented Control)of three-phase PWM(Pulse Width Modulation) rectifier,DPC(Direct Power Control)has quicker dynamic response and better anti-jamming performance A DPC approach based on virtual flux is presented for three-phase voltage source PWM rectifierThe wor- king principle of PWM rectifier is analyzed and its mathematical models are established inα-βand d-q re- ference frames,based on which,its virtual flux model is also put forward with virtual flux conception Since the reactive and active powers are calculated by estimating the virtual flux,AC voltage sensors at net side could be omittedThe control system has external closed-loop control of DC voltage output and internal closed-loop control ofpowerSimulation results show that,the virtual flux based DPC system has simpler structure,fewer sensors,higher anti-jamming capability,lesser input current distort,better static and dy- namic control performances of instantaneous power than VOC system

Reduced size single-phase PHEV charger with output second-order voltage harmonic elimination capability

Abstract: The single-phase PWM rectifier is one of the converter types applicable for the Plug-in Hybrid Electric Vehicles (PHEVs) chargers. A primary challenge with the single-phase rectifiers is the input alternative power with twice the grid frequency, which should be filtered out properly. The lack of proper filtering leads to significant second-order voltage harmonic at the charger output. This results overheating and decreasing of the battery lifetime and performance. In this paper, an active method to filter out the second-order voltage harmonic is proposed. In the proposed method, the input alternative power of the charger is absorbed by an inductive auxiliary energy storage element. Using the proposed method, the size, weight and implementation cost of the charger are decreased, as well as its power density and reliability are increased. The effectiveness of the proposed method has been verified by detailed simulation studies in MATLAB/Simulink.

Matrix Converter Based Three Phase Isolated EV Charger with Direct Power Control

Abstract: This paper presents a three-phase bi-directional electric vehicle (EV) charger utilizing a high frequency transformer isolation and single stage AC-DC topology The matrix converter changes the line frequency AC supply on the grid side to a high frequency single-phase AC, which is fed to the primary of a transformer A PWM rectifier is used at the secondary of the transformer to enable the bidirectional power flow and converting high frequency AC to DC A bipolar space-vector modulation technique is utilized to generate the high frequency single-phase AC from the three-phase AC power supply The unity power factor operation at the grid side in the charging and discharging modes with a low harmonics grid current is achieved using this topology The bi-polar space vector modulation (SVM) is implemented in a way such that the net volt-second balance in one switching cycle is zero across the transformer The direct power control scheme is used to regulate the charging current or output DC voltage by simply controlling the modulation index of the converter modulated using SVM The high frequency transformer isolation improves the power density of the overall system as well as adds safety from the user's perspective By accommodating an inductor after the full bridge converter on the secondary side, load is imitating as a current source and allows power transfer by simply controlling the modulation index of the converter

A Discontinuous PWM Strategy to Control Neutral Point Voltage for Vienna Rectifier With Improved PWM Sequence

Abstract: Vienna rectifier is a boost-type rectifier with unidirectional energy flow, which is widely used in industrial applications. To improve the power density of the Vienna rectifier, the high switching frequency is seen as an inevitable cause of larger switching losses. To reduce switching losses, discontinuous pulsewidth modulation (DPWM) is usually used. But this will cause dc offset and ac ripple on neutral point (NP) voltage. To overcome these problems, a carrier-based DPWM (CB_DPWM) method suitable for a Vienna rectifier with simple implementation is proposed to simultaneously reduce switching losses and control NP voltage. By selecting the proper clamping mode, NP voltage can be well controlled. To avoid unnecessary switching actions while switching clamping mode, an improved PWM sequence based on carrier type is given. The comparisons among space vector PWM, DPWM 1–3 presented by Zhang et al. , and the proposed CB_DPWM are presented with the corresponding simulation and experimental results, and the superiority of the proposed strategy is verified in terms of reducing switching loss and controlling NP voltage.