Recently, linear compressors of cooling systems such as refrigerators, which have a free piston driven by a linear motor, have attracted much attention because of their high efficiency. For structural reasons, linear compressors applied in refrigerators should use an AC capacitor to ensure stable control. However, AC capacitors are expensive and bulky. In this paper, we propose a new method to ...

We present results on the development a new micro electromechanical parallel plate tunable capacitor with a wide tuning range. Different from conventional parallel plate tunable capacitors, this new tunable capacitor consists of one suspended movable top plate and two fixed plates. One fixed plate and the top plate form the variable capacitor, while the other, together with the top plate, is us...

During the switching on/off of shunt capacitor banks in substations, vacuum circuit breakers (VCBs) are required to switch off or to switch on the capacitive current. Therefore, the VCBs have to be operated under a harsh condition to ensure the reliability of the equipment. This study presents a complete comparison study of ordinary and phase-controlled VCBs on switching 10 kV shunt capacitor b...

In distribution systems, in order to diminish power losses and keep voltage profiles within acceptable limits, network reconfiguration and capacitor placement are commonly used. In this paper, the Hybrid Shuffled Frog Leaping Algorithm (HSFLA) is used to optimize balanced and unbalanced radial distribution systems by means of a network reconfiguration and capacitor placement. High accuracy and ...

In this article, a multi-objective function for placement of Distributed Generation (DG) and capacitors with thetap setting of Under Load Tap Changer (ULTC) Transformer is introduced. Most of the recent articles have paidless attention to DG, capacitor placement and ULTC effects in the distribution network simultaneously. Insimulations, a comparison between different modes was carried out with,...

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...

Sensors & Transducers Journal (ISSN 1726-5479) is a peer review international journal published monthly online by International Frequency Sensor Association (IFSA). Available in electronic and CD-ROM. Abstract: A novel structure with electro-mechanically tunable capacitor for RF application is presented. The suspended electrodes are designed in such a way that both are electrostaticaly displace...

In this paper we present a photovoltaic energy harvester, realized in 0.35-μm CMOS technology. The proposed system collects light energy from the environment, by means of 2-mm2 on-chip integrated micro-solar cells, and accumulates it in an external capacitor. While the capacitor is charging, the load is disconnected. When the energy in the external capacitor is enough to operate the load for a ...

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, to enhance voltage stability of distribution systems, a Network Topology based load flow results are used to calculate Voltage Stability Index (VSI). Then an algorithm for capacitor placement (CP) based on this voltage stability index is implemented to determine the optimal locations, number and size of fixed and/or switched shunt capacitors for voltage stability enhancement, in ...