Modeling and control of permanent-magnet synchronous generators under open-switch converter faults

The mathematical modeling of open-switch faults in two-level machine-side converters and the fault-tolerant current control of isotropic permanent-magnet synchronous generators are discussed. The proposed converter model is generic for any open-switch fault and independent of the operation mode of the electrical machine. The proposed fault-tolerant current control system gives improved control performance and reduced torque ripple under open-switch faults by (i) modifying the anti-windup strategy, (ii) adapting the space-vector modulation scheme and (iii) by injecting additional reference currents. The theoretical derivations of model and control are validated by comparative simulation and measurement results. Index Terms Permanent-magnet synchronous generator, current control, fault-tolerance, fault-tolerant control, open-switch fault, anti-windup, field-oriented control, flat-top modulation, d-current injection, wind turbine systems Statement: This paper has been submitted for publication in IEEE Transactions on Power Electronics. CONTENTS