In mobile communications, radio-frequency receivers are mainly implemented using the direct-conversion architecture. A critical aspect in design of this receiver type is matching between analog in-phase (I) and quadrature (Q) paths. Any gain or phase imbalance generates image components baseband, which distort desired receive signal. Many digital solutions for online compensation effect have be...

While transmitting the data over communication channel, various problems such as communication error and mismatch arises. For reducing those errors, frequency selective I/Q imbalance using Direct Conversion transmitters can be implemented. I/Q imbalance compensation procedure has been derived and incoherent measurements are required for avoiding the need for time, frequency and phase synchroniz...

Today, with attention to increase in sensitive electrical equipments application in distribution networks and their susceptibility to the power quality deficiencies, the protection necessity of sensitive loads against undesirable effects of these disturbances are in focus. So, in this paper voltage sag deficiency and Dynamic Voltage Restorer (DVR) would be introduced as the most prevalent power...

A modular multilevel converter’s (MMC’s) submodule (SM)-capacitor voltage will increase under unbalanced grid conditions. Depending on the imbalance level, ripple can be considerably high, and it exceed pre-defined safe limits. If this occurs, converter trip, which lead to serious stability problems for grid. This paper first proposes an analytical solution deriving three-phase imbalanced SM of...

To restore the load voltage, Dynamic Voltage Restorer (DVR), which is installed between the supply and a sensitive load, should inject voltage and active power from DVR to the distribution system during voltage sag. Due to the limit of energy storage capacity of DC link, it is necessary the minimize energy injection from DVR. In this paper the techniques of the supply voltage sag compensation i...

Abstract The Japan Proton Accelerator Research Complex (J-PARC) Rapid Cycling Synchrotron (RCS) employs Magnetic Alloy (MA) loaded cavities. We realize multi-harmonic rf driving and beam loading compensation owing to the broadband characteristics of MA. currently installed cavity is conventional type one which designed be driven by tube amplifiers in a push-pull operation. operation has some ad...