A zero-voltage, zero-current switching (ZVZCS) PWM DC-DC power converter with secondary active rectifier tested as a dc current source for arc welding is described in this paper. The soft switching DC-DC converter consists of high frequency inverter, high frequency power transformer and controlled output rectifier with new secondary energy recovery turn-off snubber. Circulating current in the c...

In order to supply power from a solar panel or photo voltaic system at a low voltage to a grid at high voltage, a power electronic converter which is capable of voltage boosting and inversion is required. Newly introduced Switched Boost Inverter is capable of achieving both these objectives by a single stage. This paper presents a PWM control strategy based switched Boost Inverter (SBI) for DC ...

This paper proposes simulation and comparison of BTB (back-to-back) system combining bidirectional isolated dc/dc converters and modular multilevel cascade PWM converters [1]. The system consists of multiple converter cells connected in cascade per phase at both front ends. Each converter cell consists of a bidirectional isolated medium-frequency dc/dc converter and two voltagesource H-bridge (...

This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequen...

Single-stage AC-DC converters integrate an AC-DC front-end converter with a DC-DC backend converter. Compared with conventional two-stage AC-DC converters, single-stage ACDC converters use less components and only one controller, which is used to regulate the output voltage. As a result, the cost, size and complexity of AC-DC converters can be reduced, but single-stage converters do not perform...

The paper attempts to improve the overall power quality of an AC-DC conversion system through a fuzzy based mechanism. It extracts the reference wave for the Pulse Width Modulation (PWM) strategy, with a view to eschew the multiple frequency components of the input current, minimize its THD and arrive at nearly unity power factor. The scheme exploits the inherent advantages of a three phase ac-...

Generally uninterruptible power supply (UPS) is used to maintain a stable electric power supply to critical loads with high quality power protecting them against unexpected power failure. For example, medical facilities and data-storage computer systems require fast response, compensation and immediate availability of electrical power. Considerably affect these characteristics is energy storage...

This paper discusses the control of flexible microgrids, consisting of a Redox Flow Batteries (RFB) and a new power conditioning system (PCS) for the RFB. Considering the importance of energy storage, this study is essential in power systems that are developed cautiously. RFB is connected to power system by a DC/DC or DC/AC converter to produce a DC voltage. It is very important that this conve...