Performance analysis and evaluation of reactive power compensating electric spring with linear loads

• Published in: International journal of electrical power & energy systems 2018-10, Vol.101, p.116-126
• Main Authors: Soni, Jayantika, Sen, Binita, Kanakesh, V.K., Panda, S.K.
• Format: Article
• Language: English
• Subjects: Inverter; Microgrid; Renewable energy; Smartgrid; VAR compensator
• ISSN: 0142-0615; 1879-3517
• DOI: 10.1016/j.ijepes.2018.03.017

•Performance of the reactive power compensating electric spring (ES) is evaluated.•Impact of critical and non-critical load impedances on performance of ES is studied.•Impact of type of critical and non-critical load on performance of ES is studied.•ES interaction with renewable energy source inthe system is explained.•Operating principles of the ES and its interaction with the renewable energy sources in the system are explained using the understanding from the ac power transfer between two active power sources. Reliance on renewable energy sources (RESs) such as solar and wind has increased to build a sustainable environment, however, their substantial implementation is hindered by their intermittency. Electric Spring (ES) is one of the technologies to mitigate the intermittent nature of the RESs. In an isolated RES powered microgrid, the ES in conjunction with the non-critical loads in a system like water heaters, refrigerators, and air-conditioners can regulate voltage of critical loads like security system, servers etc. This paper establishes the operating principles of the ES (with reactive power compensation only) and its interaction with RESs based on the understanding of AC power transfer between two sources. The accurate phasors in a system under two scenarios, with and without ES, are drawn. Also, performance of the ES is analyzed and evaluated with respect to variations in the loads (linear) and their types. It is augmented with analytical justifications and validated through simulations and experimental studies. Also, through analytical expressions, simulations, and experiments the importance of the non-critical load on the performance of the ES is illustrated. It is also highlighted that the compensation capabilities of the ES remain the same irrespective of the types of non-critical load.