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...

Forward converters generally exhibit poor power factor when employing in the AC-DC conversion, due to the presence of zero input current near the zero crossing of line input voltage. In this paper, a single-switch forward converter with high power factor and low storage capacitor voltage stress is proposed. By adding a stack up voltage on top of the reflected input voltage on the forward conver...

This paper presents new and efficient modulation techniques applied on the recently introduced compact nine-level switched-capacitor inverter (C9LSCI). The also discusses performance of under selective harmonic elimination (SHE) mitigation (SHM) based heuristic Bat-Algorithm (BA) technique. Two employing CD-type carrier waves M-type are proposed, showing a rise in efficiency, an increase RMS vo...

The modular multilevel converter is improved topology for high-voltage, high-power applications since the cascaded sub modules can generate high-voltage waveforms with excellent harmonic performance at low switching frequencies. Many publications have been presented on the modulation and control of this converter type, some of which are based on phase-shifted carrier modulation. This paper pres...

In this paper, we have proposed and designed the new structure of a RF-MEMS voltage tunable capacitor, which have two-movable parallel plates using electrostatic method and can be fabricated by the MEMS technology. Capacitance of the designed voltage tunable capacitor has from 1.0pF to 1.48pF as the applied bias voltage from 0.5V to 2.52V. The effective area and the distance of the capacitor pl...

This paper presents a review and analysis of multilevel inverter topologies. Multilevel inverters are most widely used for medium-voltage high-power converter like fans, pumps and material transport drives. In this active area, different inverter topologies, circuits, advantages and drawbacks are discussed. Multilevel Inverter topologies such as diode-clamped, flyingcapacitor, cascaded H-bridge...

This paper proposes a capacitance estimation method of the dc-link capacitor for brushless DC motor (BLDCM) drive systems. In order to estimate the dc-link capacitance, the BLDCM is operated in quadrant-II or -IV among four-quadrant operation. Quadrant-II and -IV are called reverse braking and forward braking, respectively. During the braking operation of the BLDCM, the capacitor is charged by ...

In this paper mainly presents about the DSTATCOM and control methodology of DC capacitor voltage, generally, the dc capacitor voltage is regulated using a PI controller when various control algorithms are used for load compensation. However, during load changes, there is considerable variation in dc capacitor voltage which might affect compensation. In this work, a fuzzy logic based supervisory...

With the development of flywheel technology, speed and voltage level continue to increase. The Z-type self-balancing modular multilevel converter can have a wide frequency range at medium is suitable for driving application. However, current characteristics variable drive still affect capacitor balance in each phase-leg. new be achieved by controlling circulating current. This paper proposed co...