The unified power flow controller (UPFC) is a typical FACTS (Flexible AC Transmission Systems) device that is capable of instantaneous control of transmission line parameters. This paper presents the transient model and control system of UPFC. The presented control system enables the UPFC to following the exchanges of line active and reactive power reference values, regulating the DC link and b...

Development of Electrical Vehicles (EVs) has been created many challenges and also advantages for grids. One of the most important subjects is capability of which as energy storage device. In this paper, role of EVs has been studied as useful element in microgrids as energy storage device to reduce the on-peak load in microgrid and decrease the total cost of microgrid. For this goal the problem...

Abstract: In this paper we described the structure and working principle of an interruption generator based on voltage source converters (VSCs). The main circuit parameters of the VSCs are determined according to the target of power transfer capability, harmonic suppression, and dynamic response capability. A state feedback linearization method in nonlinear differential geometry theory was used...

The fault recovery of VSC-HVDC transmission system is often influenced by many factors, such as the reactive power compensation characteristics of the inverter and the dynamic performance of DC controllers. In this paper, the PSCAD/ EMTDC simulation tool is used to study the dynamic recovery performance of VSC-HVDC system for several different var compensating devices in VSC-HVDC inverter-Fixed...

in this paper, a new circuit is proposed for step-up z-source inverter based on qzsi (quasi-z-source inverter). the proposed topology inherits all advantages of the conventional topology. the proposed topology in comparison with conventional topology reduces the st (shoot-through) duty cycle by over 25% at the same voltage boost factor. theoretical analysis of the proposed qzsi in the st and no...

a detailed model of wind power station, including double fed induction generator, dfig is presented in this paper. two control mechanisms are included in the model. the inner control system uses stator flux oriented control for the rotor side converter and grid voltage vector control for the grid side converter. the outer control system is used for wind turbine pitch angle. pscad/emtdc is used ...

This paper proposes an operation methodology for interfacing synchronous generator and energy storage system (ESS) by replacing conventional governor. research introduces management scheme with droop control method frequency regulation in coordination generator. For regulation, can take advantage of the ESS instead governor, its relatively fast characteristics, leading to less frequent deviatio...

Distributed generations can be divided into traditional synchronous generators and inverter interfaced distributed (IIDG) according to their different operation mode. While the fault characteristics of IIDG is from Generators, in-depth analysis on output are foundation micro grid protection. The mathematical models under P/Q V/F control strategy discussed. After simplifying its model, studied u...

This paper proposes a protection method for single line-to-ground (SLG) faults in an ungrounded offshore wind farm with fully-rated converter-based wind turbines. The proposed method uses the unsynchronized current phasors measured by unit protections installed at the connection point of the fully-rated converter (FRC)-based wind turbines (WTs). Each unit protection collects the unsynchronized ...