Dead-Time Effect Analysis and Compensation for Deadbeat-Direct Torque and Flux Control of PMSMs to Eliminate Steady-State Error

Although deadbeat-direct torque and flux control (DB-DTFC) can realize excellent dynamic responses for permanent magnet synchronous machine (PMSM) drives, it suffers from problems of steady-state error and transient oscillation due to dead-time effect. To solve these problems, this paper proposes a dead-time compensation scheme. In order to investigate the effect of dead-time on DB-DTFC, the voltage distortion is derived and analyzed. Then, by both mathematical and graphical methods, it is originally verified that dead-time would lead to steady-state error in DB-DTFC. Therefore, a zero time delay compensation method which could overcome the weakness of the sampling and calculation time delay and eliminate steady-state error and undesired transient oscillation is proposed. Hence, the degradation caused by dead-time could be virtually mitigated and thus deadbeat responses are guaranteed. Finally, the proposed compensation scheme is experimentally validated on a 10. 2kW PMSM drive platform.