In a conventional grid connected photovoltaic system employing centralized inverter with long strings connected across dc-link, the performance of the plant in terms of power generation and efficiency is not optimal especially during partial shading and/or panel mismatch conditions. To improve the power yield during such conditions, a splitmultistring configuration employing 3Level Neutral Poin...

Electrolytic capacitors are a bottleneck for inverter lifetime. Because of the large capacitances used in PV-inverters, a direct replacement by film-capacitors is not feasible for most topologies. This paper presents an active circuit which acts as an interface between the DC-link of a PV-inverter and an additional storage capacitor. By allowing a large voltage ripple at the storage capacitor, ...

This paper presents an alternate quasi-resonant dc link (QRDCL) circuit for soft switched inverters which does not require paralleling of a charged capacitor with another charged capacitor or a voltage source. The circuit momentarily pulls down the DC link voltage to zero as commandled by the control circuit to facilitate zero voltage switching (ZVS) of inverter devices. Operation of this circu...

Multi-level inverter technology has emerged recently as a very important alternative in the area of high-power medium-voltage energy control. In this paper, the most important topologies like diode-clamped inverter (neutral-point clamped), capacitor-clamped (flying capacitor), and cascaded multi cell with separate dc sources. In this paper, we proposed a new multi-level inverter topology based ...

In this paper, dynamic performance of a transformerless cascaded PWM static synchronous shunt compensator (STATCOM) based on a novel control scheme is investigated for bus voltage regulation in a 6.6kV distribution system. The transformerless STATCOM consists of a thirteen-level cascaded H-bridge inverter, in which each voltage source H-bridge inverter should be equipped with a floating and iso...

Absrracl--A dual two-level inverter fed open-end winding induction motor drive is proposed in this paper. A total of 64 voltage space phasor combinations are possible in this scheme as each inverter produces eight voltage space phasors. The proposed scheme produces voltage space phasor locations similar to that of a 3-level inverter. In a 3-level Inverter the series connected DC link capacitors...

In the viewpoint of reliability implication and cost effectiveness of three phase inverter, there should be less device count in inverter topology and fewer losses in the semiconductor switches. The earlier reported less device count topology by many research groups are facing the problem of Total Harmonic Distortion (THD). The imperfect design value of DC link capacitor is the main reason of H...

In this paper, battery/ultracapacitor hybrid energy storage system (HESS) is proposed for electric vehicles, it is used to large dc-dc converter by using ultra capacitor and battery. It is also use the dc link for the purpose of maintain the peak voltage value. By the help of battery and ultracapacitor they are operate. The battery is used to charging the capacitor in case of discharge the capa...

In this paper, battery/ultracapacitor hybrid energy storage system (HESS) is proposed for electric vehicles, it is used to large dc-dc converter by using ultra capacitor and battery. It is also use the dc link for the purpose of maintain the peak voltage value. By the help of battery and ultracapacitor they are operate. The battery is used to charging the capacitor in case of discharge the capa...

This paper compares four converter topologies for the implementation of flexible ac transmission system (FACTS) controllers: three multilevel topologies (multipoint clamped (MPC), chain, and nested cell) and the well-established multipulse topology. In keeping with the need to implement very-high-power inverters, switching frequency is restricted to line frequency. The study addresses device co...