Power Control Of PWM Rectifier Research Articles

A new super-twisting sliding mode control based direct instantaneous power control of PWM-rectifier connected to grid

A new super-twisting sliding mode control based direct instantaneous power control of PWM-rectifier connected to grid

Direct Power Control of PWM Rectifiers With Online Inductance Identification Under Unbalanced and Distorted Network Conditions

In the conventional direct power control (DPC) methods, the grid currents are highly distorted, and substantial ripple is present in the dc-bus voltage under unbalanced and distorted grid conditions. Various improved DPC methods have been proposed to address these problems, but these methods are generally complicated and not easy to use because of the complex controlling structures, need for considerable tuning, and so on. This paper proposes an improved DPC method obtained by simply adding a compensation term to the original power references. The compensation power is obtained by analyzing the power ripple in the input line inductance based on extended power theory. The reference voltage vector is subsequently calculated from the new power reference and synthesized by space vector modulation. To improve the robustness of the proposed DPC against inductance variations, an online inductance identification technique based on the gradient correction method is proposed and combined with the proposed DPC. The presented simulation and experimental results demonstrate that the proposed method can achieve sinusoidal grid currents and significantly reduce the dc-voltage ripple even with mismatched inductance under unbalanced and distorted grid conditions.

Power Control of PWM Rectifier with Resistive and Reactive Load

The realization of power modeling and power control of PWM rectifier with resistive and reactive load is based on the method of Lyapunov. Firstly, PWM rectifier's mathematical power model is established in d-q synchronous rotating coordinates, and balance point is found according to the control requirement of the system and analysis the stability of the equilibrium point according to the Lyapunov method and invariant theory. Then PWM rectifier's power controller has been gotten through damping injection. The designed power controller realizes fast voltage tracking and makes the net side power factor as 1, which has great inhibitory effect on resistive and inductive disturbance. Influence on the system exerted by different damping injection is analyzed and feasibility of PWM rectifier's power control based on Lyapunov method is verified.

Instantaneous Power Control of PWM Rectifier Using Hysteresis Regulator with Frequency Characteristic

This paper proposes a hysteresis regulator with a frequency characteristic, which reduces specific harmonic power in a direct power control system of a current-source PWM rectifier. The method virtually adjusts the hysteresis bandwidth in association with frequencies of the power pulsation; hence the regulator is capable to filter specific frequency components of the input current as well as the power. The paper describes a theoretical aspect of the proposed approach, and presents some experimental results of a particular case, where the 5th and the 7th harmonic input currents are mainly suppressed by eliminating the 6th harmonic component of the active power.