Event-Synchronous Time-Asynchronous Method for Controller HIL Simulation of 10 kVA Modular Multilevel Converters

This letter presents an event-synchronous time-asynchronous (ESTA) method for controller hardware-in-the-loop (CHIL) simulations of modular multilevel converters (MMCs). The proposed method aims to address the issue of extensive power circuit simulation calculations, which may result in incomplete data interaction within an interaction cycle and, subsequently, cause CHIL simulation failure. Unlike the conventional time-synchronous simulations, the proposed ESTA method employs data interaction events to trigger simulation and control calculations. Furthermore, state and switching events are utilized to drive simulation calculations, reducing the calculation points of the simulator. As a result, the controller and simulator in CHIL systems exhibit synchronous event logic and asynchronous timing. The proposed ESTA method allows for the accurate CHIL simulations even when the simulator faces significant computational tasks. The simulated and experimental results from a 10 kVA MMC are provided to validate the proposed ESTA method. This letter provides an effective method for simulating large-scale MMCs in the CHIL simulation system, offering a promising avenue for this field.