Electromechanical systems generating constant frequency alternating current

Flexible Alternating Current Transmission Systems

Electrical stimulation using kilohertz-frequency alternating current.

Transcutaneous electrical stimulation using kilohertz-frequency alternating current (AC) became popular in the 1950s with the introduction of "interferential currents," promoted as a means of producing depth-efficient stimulation of nerve and muscle. Later, "Russian current" was adopted as a means of muscle strengthening. This article reviews some clinically relevant, laboratory-based studies t...

Improvement of Power System Condition by Placement of Flexible Alternating Current Transmission Systems devices

Flexible Alternating Current Transmission Systems (FACTS) devices have been used for several targets in power system, one of the main contributions of the devices is improving operation conditions. In this paper, two types of these devices have been placed to raise voltage profile, minimizing system loss and arising loadability. The suggested FACTS devices are: Unified Power Flow Controller (UP...

A Short-Current Control Method for Constant Frequency Current-Fed Wireless Power Transfer Systems

Abstract: Frequency drift is a serious problem in Current-Fed Wireless Power Transfer (WPT) systems. When the operating frequency is drifting from the inherent Zero Voltage Switching (ZVS) frequency of resonant network, large short currents will appear and damage the switches. In this paper, an inductance-dampening method is proposed to inhibit short currents and achieve constant-frequency oper...

FACTS Flexible Alternating Current Transmission Systems

Increased demands on transmission, absence of long-term planning and the need to provide open access to generating companies and customers have created tendencies toward less security and reduced quality of supply. The FACTS technology is essential to alleviate some but not all of these difficulties. The FACTS technology opens up new opportunities for controlling power and enhancing the usable ...