6MW, 10KV High Speed PMSM Digital Drive System for Highly Efficient Compressors

Modern gas compressor systems in the megawatt range strive for high reliability and efficiency. High speed motors with active magnetic bearings (AMB) can be directly coupled to the compressor without need of a gearbox. This technology has already been applied utilizing high speed induction motors.The paper outlines a new digital drive solution utilizing a permanent magnet synchronous motor (PMSM) with a power of 6MW fed by a 10kV multilevel medium voltage inverter. Measurement and simulation results show a significant efficiency improvement. The inverter is designed for high reliability with built-in redundancy reaching MTBF values of more than 13 years. The inverter topology is compared with known solutions and the specific requirements of the PMSM motor are explained.Digital drive train functionalities such as predictive maintenance and virtual commissioning are evaluated. Utilizing digital twins, the drive system can proactively anticipate anomalies and generate alerts.A comparison of losses with a state-of-the-art high-speed compressor indicates the potential energy savings and resulting CO2 reduction.