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In this paper, a grid connected wind farm with a static synchronous compensator (STATCOM) is modeled in Real Time Digital Simulator (RTDS) environment to analyze its dynamic and transient characteristics in real system. This work is also a part of future power hardware-in-loop (PHIL) test and therefore, individual components are models considering practical viewpoints. Wind turbines and generators of a wind farm, power grid, and control system are realized in the large time-step main network. However, 2-level voltage source converter based STATCOM is modeled in RTDS small time-step environment to adapt with higher switching frequency, where interface transformer is used to link the different time step subnetworks. Suitable control strategy for STATCOM is developed to augment the stability of wind farm considering that capacitor connected at the terminal of wind generator is reduced up to certain percentage. Option for integrating anemometer for dynamic characteristics analysis, difficulties of STATCOM switching schemes for implementing PHIL testing in RTDS environment are discussed. Results are compared with Laboratory standard power system software PSCAD/EMTDC and the advantages of using RTDS in dynamic and transient characteristics analyses of wind farm are also demonstrated clearly.

This is the author's version of an article published in Sustainable Energy Technologies and Assessments. Changes were made to this version by the publisher prior to publication.

This paper models the performance of lead acid batteries operating in battery energy storage systems (BESS) for renewable energy applications. The considered system consists of a permanent magnet generator based wind turbine interfaced to the grid through fully rated converters. A battery energy storage system, interfaced to the grid via STATCOM is used for active power smoothing. A low power experimental BESS is interfaced to the system model. Two battery models, a simple-and a detailed-one, are implemented and verified against experimental data. A simple experimental test is proposed for measuring the battery internal resistance. The salient feature of this paper is the examination of the battery terminal voltage variation for the non-regular current profiles requested from the battery bank in renewable energy.

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In this paper, a grid connected variable speed wind turbine (VSWT) PMSG integrated with the NaS-type battery energy storage system (BESS) is modeled in the real-time digital simulator (RTDS) to analyze the performance in a real system. This study is also a part of the future power hardware-in-loop (PHIL) test; therefore, individual components are modeled from the practical standpoint. The wind turbine, power grid, and control system are modeled in the largetime-step main network; however, the wind generator (PMSG), frequency converter (FC), and BESS integrated with STATCOM are modeled in the RTDS VSC small-time-step network to take into consideration the higher-switchingfrequency phenomena. The interface transformer is used to connect the different-time-step subnetworks. The option of integrating the anemometer is kept open for a future PHIL test. The simulation results are compared with those obtained from the laboratory standard power system software PSCAD/EMTDC to validate the model developed in the RTDS/RSCAD.

This paper presents a new operational scheme and methodology to analyze the steady-state and low voltage ride through (LVRT) characteristics of a grid connected variable speed wind turbine driven permanent magnet synchronous generator (VSWT-PMSG) using Real Time Digital Simulator (RTDS). This work is also a part of the future power-hardware-in-loop (PHIL) test. VSWT-PMSG uses fully controlled frequency converter (FC) for the grid interfacing. For the sake of detail analysis, determining precise switching frequency, and future PHIL test, the FC is modeled in VSC small time-step of the RTDS. Non-sinusoidal Pulse width modulation (PWM) technique is used in this study by injecting the 3 rd harmonics in the reference three phase voltage signals to increase the output voltage of FC. A salient feature of this study is the incorporation of realistic grid, i.e. three phase supply voltage in real time simulation of RTDS/RSCAD to analyze both steady state and LVRT characteristics of grid connected VSWT-PMSG. The supply-voltage signals are subjected with the noise, e.g., voltage notches by the use of non-linear load. Therefore, voltage notching effect is taken into consideration while the controller effectiveness of the FC is examined under different operating conditions. With the incorporation of supply-voltage fluctuations, its influence on the VSWT-PMSG is analyzed with different switching frequencies of the FC. Extensive comparative study is carried out using both ideal and realistic grids.

HardwareReal time digital simulator hardware is based on the parallel processing architecture and has been designed specially to solve the electromagnetic transient simulation algorithm. RTDS