Comparison and Analysis of DSIM and SIMULINK Simulation Based on MMC System
literature reference
Paper publication. Published at the 2021 IEEE 4th International Electrical and Energy Conference (CIEEC).
Brief Introduction
Due to its versatile output capabilities, scalability, and high modularity, the Modular Multilevel Converter (MMC) is increasingly applied across various sectors such as high-voltage direct current transmission and renewable energy generation systems. However, the numerous switching devices within the MMC generate electromagnetic interference (EMI), significantly affecting system stability.
DSIM is utilized in this paper. “This simulation mechanism greatly shortens the time cost and makes the power electronics simulation more convenient. In addition, it can also simulate the transient process of switching devices.” This paper compares DSIM results with Simulink, illustrating DSIM's capabilities in simulating power electronic circuits.
MMC-HVDC system simulation using DSIM
“A 17-level MMC-HVDC system is built on the DSIM platform. The system adopts the nearest level modulation (NLM), contains an inner loop current controller, can perform closed-loop control, and performs capacitor voltage balance based on a sequencing algorithm.”
In this paper, MMC systems of the same scale are also built on Simulink, comparing DSIM with Simulink from two aspects: general simulation model of MMC and MMC simulation model with stray parameters.
For general MMC simulation model, it can be seen that “the DSIM software can simulate the transient change process of the IGBT, while the Simulink IGBT is an ideal model, and its switching action changes instantaneously. Therefore, the IGBT model of DSIM is closer to the actual situation, and the simulation results are more accurate”. “For the simulation speed, when the system running time is 0.4 s, and the step length is 0.1μs, the simulation time of Simulink software is 8 minutes and 20 seconds. DSIM simulation software does not need to set the step length due to its adaptive step length, and its simulation time is 36 seconds. The difference between the two is nearly 14 times. It can be seen that the discrete-state event-driven simulation mechanism adopted by DISM simulation software is effective and can greatly increase the simulation speed, and the results will not be affected.”
For model with stray parameters, DSIM could accomplish the MMC simulation while simulating the switching transient. “The spectrum obtained by the DSIM software has more high-order harmonics with less amplitude, which are ignored by the Simulink software.”