This paper discusses the Dynamic voltage restorer (DVR) operation and control for Voltage sags compensation. DVR is a series connected power electronic based device that can quickly mitigate the voltage sags in the system and restore the load voltage to the pre-fault value. Voltage sag associated with faults in transmission and distribution systems, energizing of transformers, and starting of l...

Ultralight axions and dark photons are well-motivated matter candidates. Inside the plasma, once mass of ultralight candidates equals plasma frequency, they can resonantly convert into electromagnetic waves, due to coupling between particles standard model photons. The converted waves monochromatic. In this article, we review development using radio detectors search for conversions in solar cor...

multilevel inverters has big placement advantages in power electronics and its application can be mentioned to facts tools such as upfc – d-statcom. therefore, nowadays multilevel inverters have created vast field’s research and researchers are trying to present appropriate structures with fewer keys and greater advantages. the main advantages of multilevel inverters mentioned are low-key volta...

In this paper, a boost converter with a clamp circuit is proposed for high intensity discharge (HID) lamp application. The clamp circuit provides zero voltage turn on for both main and clamp switches. Compared to conventional boost converters, the proposed converter has the following advantages: (i) high voltage gain without suffering from extreme duty ratio, (ii) low stress on the switches and...

This paper studies the effects of symmetrical voltage sags on the operational characteristics of a Permanent Magnet Synchronous Motor (PMSM) by Finite Element Method (FEM). Voltage sags may cause high torque pulsations which can damage the shaft or equipment connected to the motor. By recognizing the critical voltage sags, sags that produce hazardous torque variations could be prevented. Simula...

We study behavior of bulk gauge field in the bigravity model in which two positive tension AdS4 branes in AdS5 bulk are included. We solve the equations of motions for Kaluza-Klein modes and determine the mass spectrum. It is shown that unlike the case of graviton, we find no ultralight Kaluza-Klein modes in the spectrum. E-mail:[email protected] JSPS Research Fellow on leave from Yukawa Instit...