To restore the load voltage, Dynamic Voltage Restorer (DVR), which is installed between the supply and a sensitive load, should inject voltage and active power from DVR to the distribution system during voltage sag. Due to the limit of energy storage capacity of DC link, it is necessary the minimize energy injection from DVR. In this paper the techniques of the supply voltage sag compensation i...

We propose a new converter control scheme for a converter–inverter system. The strategy is to fully utilize the inverter dynamics in controlling the converter dynamics. We obtain the power dynamics for both converter and inverter systems, and control the converter power so that it matches the required inverter power exactly. Then, in the ideal case, no power flows through the dc-link capacitors...

The objective of this paper is to investigate the performance of 8/6 switched reluctance motor (SRM) when excited with sinusoidal voltage. The conventional R dump converter provides DC excitation with the help of capacitor. In this paper the converter used is the modified R dump converter without DC link capacitor providing AC or sinusoidal excitation. Torque ripple and speed ripple are investi...

The performance of D-STATCOM depends on capacitor voltage regulation. In D-STATCOM, the nonlinear controller is preferred to linear controller. Regulating and fixing the capacitor DC voltage in DSTATCOM can improve the system dynamic such as capacitor voltage response, current response and modulation index. The regulation of DC capacitor voltage based on optimal PI co-efficient. In conventional...

Three-phase three-wire Distribution Static Compensator (DSTATCOM) with Photovoltaic (PV) array or battery operated DC-DC boost converter is proposed in this paper. The proposed DSTATCOM consists of a three-leg Voltage Source Converter (VSC) with a DC bus capacitor and it provides continuous reactive power compensation, source harmonic reduction and load compensation throughout the day. With the...

In this paper we propose fuzzy control of DC-link capacitor voltage of three-phase four-wire DSTATCOM for power quality improvement in distribution network. It is designed to compensate reactive power and to eliminate harmonic currents. DSTATCOM regulates the voltage at the point of common coupling (PCC) by injecting reactive power to the PCC. During load changes there is considerable variation...

This paper proposes a feed-forward control in a halfbridge resonant dc link inverter. The configuration of feed-forward control is based on synchronous sigma-delta modulation and the halfbridge resonant dc link inverter consists of two inductors, one capacitor and two power switches. The simulation results show the proposed technique can reject non-ideal dc bus improving the total harmonic dist...

A new control technique known as inverted error deviation (IED) control is incorporated into the main DC-link capacitor voltage regulation algorithm of a three-level neutral-point diode clamped (NPC) inverter-based shunt active power filter (SAPF) to enhance its performance in overall DC-link voltage regulation so as to improve its harmonics mitigation performances. In the SAPF controller, DC-l...

This paper presents a bidirectional DC-DC converter suitable for low-voltage super capacitor-based electric energy storage systems. The DC-DC converter presented here consists of a full-bridge circuit and a current-fed push-pull circuit with a high frequency (HF) transformer-link. In order to reduce the device-conduction losses due to the large current of the super capacitor as well as unnecess...