# A Deadbeat Current and Flux Vector Control for IPMSM Drive with High Dynamic Performance
###### Abstract  
In this paper, a new deadbeat stator current and flux linkage vector control (DB-CFVC) scheme for interior permanent magnet synchronous machines (IPMSM) is proposed. The control structure is simplified by implementing the proposed flux linkage vector control method in the \(\alpha\)-\(\beta\) stationary coordinate. Unlike conventional deadbeat methods, the dynamic performance of the proposed DB-CFVC can be enhanced while voltage command saturation and over output current are avoided. This is achieved with a \"reinforced\" phase angle reference of stator flux linkage vector by considering rotor speed error and maximum voltage to properly enhance the quality of the calculated flux phase angle command. SVM to generate an output voltage at VSI. In the DB-PC, the desired values can be attained by one beat control, faster than conventional vector control methods, and it can neglect the complexity of controller parameter tuning. However, like MPCs, the DB-PCs highly depend on PMSM model, and its control quality is affected by processing delays, i.e., sampling and computing time. With the one-step delay compensation algorithm adopted [11; 14; 15; 16; 17; 18; 19], the delay problem has been resolved. Furthermore, the disturbance observer [12; 15; 16] or model-free [20] techniques were also developed to overcome the effects of motor parameter variations/mismatch and unknown disturbances. The combination of the DB-PC methods with current control (CC), flux vector control (FVC), or direct torque and flux control (DTFC) has recently been investigated [13; 14; 15; 16; 17] to enhance control performance. In previous studies [15; 16], the robust deadbeat predictive current control (DB-PCC) was presented with a sliding mode disturbance observer to obtain high-accuracy output current. Although accurate estimation of flux linkage and torque is not necessary in these DB-PCCs, the torque and flux linkage that are controlled indirectly via the rotor coordinate (\(d\)-\(q\))'s current elements may produce a weaker dynamic response than a direct one. A modified DB-PCC for high-speed PMSM was presented [17], where the voltage command in the stationary frame (\(\alpha\)-\(\beta\)) is calculated from the current elements in \(d\)-\(q\) frame indirectly via flux linkage elements in the \(\alpha\)-\(\beta\) frame. However, this seems to be another way of employing conventional DB-PCC in \(\alpha\)-\(\beta\) frame via the PMSM mathematical model. The deadbeat direct-flux vector control (DB-DFVC) developed in [18; 19] and the DB-DTFC in [13; 14] possess excellent dynamic performance, where both flux linkage and torque calculations are performed in the rotating frames of rotor or stator flux coordinate. Nonetheless, the predicted stator current and flux linkage in the one-step delay algorithm require more computation effort than those in the DB-PCC and relate much to motor parameters. In addition, coordinate transformation is necessary for most of the calculations in the rotating frame. For high-speed operations, the output voltage commands may likely exceed the allowable limit when large errors between command and feedback are combined with the high-bandwidth characteristic in the BD-PC. The voltage saturation would then restrict the dynamic performance. Overmodulation is often used to overcome this problem, but it also generates a non-sinusoidal output voltage resulting in increased torque ripple. A hybrid DB-PCC with classic MPC [21] was developed to provide output current command delivered from an optimal geometrical solution. This avoids saturation of current and voltage and the dynamics are improved. A DB-DTFC method based on torque and flux vector trajectories in \(d\)-\(q\) frame with an improvement on a minimum-time ramp trajectory method was presented to mitigate the voltage limit problem [22], wherewith fast and stable transient dynamics for IPMSM drives can be achieved.