Capacitor switching leads to high-frequency, high-magnitude currents, causing voltage fluctuations and equipment stress. Furthermore, Transient Recovery Voltage (TRV) during capacitors disconnection results in oscillations and high-magnitude voltage spikes. This study emphasis on the comparative analysis of inrush current and TRV profiles derived on two different tools, EMTP and PSCAD. The findings highlight the versatility of both, EMTP and PSCAD as electromagnetic transient simulators, offering users the flexibility to select based on specific requirements and familiarity.
Simulation Details
The system, illustrated in Fig. 1 and Fig. 2 with identical parameters, is modelled to examine capacitor-switching transients for two cases: switching with and without a reactor.
Case 1: In the system illustrated in Fig. 1, capacitor bank C2 is energized at t=0.3 sec, with C1 already in service.
Case 2: Capacitor bank C2, connected through CB2 and series reactor L1, is switched on at t=0.3 sec, as illustrated in Fig. 2, with C1 already active in the system.
The simulation results are summarized in the following section.
Simulation Results
The typical systems as described in Fig. 1 and Fig. 2 are simulated to derive the inrush current, transient recovery voltage profiles using EMTP and PSCAD, subsequent to the capacitor switching and illustrated as below.
Case 1: Inrush current and TRV profiles
Figure 4. Comparison of T59 profiles for case 2
Case 2: Inrush current and TRV profiles
derived from PSCAD Figure 5. Comparison of inrush current profiles for case 2
Figure 6. Comparison of T59 profiles for case 2
Conclusion
The outcomes of this study highlights capabilities and reliability of EMTP and PSCAD as leading simulation tools. An objective comparison offers an impartial perspective, provides users the flexibility to select the tools that best suits their preferences and project needs, without compromising on accuracy and questioning its competence. Other comparative studies like FMBT, Insulation Co-ordination and Voltage Switching Stability of large transformer is under progress.
Arvind Mehta is the Founder & Chairman of Elcon Engineers Pvt. Ltd. He received the BE degree in Electrical Engineering from Maharaja Sayajirao University, Vadodara, India in 1973. His specialization is in the field of power system study, design, analysis and providing solutions for industries and utilities. His job experience in Jyoti Ltd. and Tata Consulting Engineers leveraged in the growth of Elcon Engineers Pvt. Ltd. right from its establishment.
Chinmay Y. Jani received the BE degree in Electrical Engineering from Gujarat University, Ahmedabad, India in 2009 and M. Tech degree with specialization in Electrical Power Systems from Nirma University, Ahmedabad, India in 2013. He is currently pursuing his Ph. D. at the Department of Electrical Engineering, Institute of Technology, Nirma University, Ahmedabad, India and associated with Elcon Engineers Pvt. Ltd.
