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To reduce the computational complexity of traditional model predictive torque control (MPTC) and improve the sensitivity of predictive control to disturbances, an improved three vector model predictive control strategy applied in permanent magnet synchronous motor (PMSM) is proposed. First, the principle of deadbeat synchronization between torque and flux linkage is adopted to reduce six candidate vectors in traditional torque prediction to two, and the cost function is designed to select the optimal voltage vector. In addition, disturbance observation compensation is introduced to compensate for the influence of load disturbance on the control performance of the predictive model. As experimental results show, the proposed three-vector model predictive torque control can obtain small torque ripple and current harmonics both in steady state and dynamic state.

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High efficiency, high power density and wide output voltage are required for on-board charger (OBC) applications. LLC resonant converter has the advantage of achieving zero-voltage switching for variable frequency and different load conditions. Compared with conventional fundamental harmonic approximation method, operation-mode analysis based on the time domain model provides an accurate description of resonant current, voltage and DC gain. In this study, the efficiencyoriented modified method is proposed based on the operation-mode analysis. The converter inductance ratio, characteristic impedance and transformer turns ratio are optimised and both-side soft switching can be achieved in the high output voltage region. Conduction loss can be minimised by optimising resonant parameters. Finally, a high-efficiency design method is proposed and validated through experiments on a 3.3 kW prototype applied in OBC. The prototype of the LLC resonant converter has been tested for dynamic charging voltage (230-430 V) with a peak efficiency value of 98.5%.

To improve the control accuracy of the model prediction current (MPC) loop of a permanent magnet synchronous motor (PMSM), a new high-order super-twisting sliding-mode controller combined with a sliding-mode disturbance observer is proposed as a speed control strategy. Firstly, the linear term is added to the scaling term based on the original algorithm, which enhances robustness while weakening jitter. In addition, load perturbations and parameter uptake in the system are considered. The perturbation observation error is introduced into the switching gain function, and an improved sliding-mode disturbance observer is designed as feedforward compensation. The disturbance immunity of the system is effectively enhanced. Simulated and experimental results verify the correctness and effectiveness of this control strategy.