Detailed and averaged models for a 401-level MMC-HVDC system

Abstract

Electrical engineering, Ecole Polytechnique Voltage Source Converter (VSC) technologies present a bright opportunity in a variety of fields within the power system industry. New Modular Multilevel Converters (MMCs) are expected to supersede two-and three-level VSC-based technologies for HVDC applications due to their recognized advantages in terms of scalability, performance and efficiency. Computational burden introduced by detailed modeling of MMC-HVDC systems in EMT-type programs complicates the study of transients especially when such systems are integrated into a large network. This paper presents a novel average-value model (AVM) for efficient and accurate representation of a detailed MMC-HVDC system. It also develops a detailed 401-level MMC-HVDC model for validating the AVM and studies the performance of both models when integrated into a large 400 kV transmission system in Europe. The results show that the AVM is significantly more efficient while maintaining its accuracy for the dynamic response of the overall system.

Frequency stabilisation using VSC-HVDC

“…The VSC HVDC link provides full power reversal with the designed droop setting. A rate limiter [11] can be added to the dq current reference value if this needs to be limited. In this case, an emergency rate limiter of 1GW/s and a reduced rate limiter of 500MW/s are assumed to be applied in the VSC HVDC link.…”

Phase-locked loops for grid-tied inverters: comparison and testing

“…The DC link voltage is ±320 kV with capacity of 1000 MW. These ratings are selected according to [15]. Fault introduction facilities are implemented after the transformer in order to test the fault ride through ability of the MMC model.…”

Making VSC-HVDC control robust to geomagnetically induced current

“…The HV side AC voltage in the model is 400 kV line-to-line, while the LV side AC voltage is 333 kV line-to-line. The DC link voltage is ±320 kV with capacity of 1000 MW [26].…”