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During transient process, it may take plenty of steps for PMSM to reach the reference torque and flux linkage. Multistep model predictive torque and flux control (MPTC) can select the best sequence of voltage vectors from the initial state to the reference state to achieve the fastest torque response. However, the computation burden is a significant challenge for real-time implementation. This paper proposes a novel fast-response MPTC strategy for PMSM drives. The reference torque is converted to flux linkage in d-axis and q-axis to eliminate the weighting factor in cost function. During the transient process, Pontryagin's maximum principle is used to design minimum-time flux linkage trajectories from the initial state to the reference state. In each control period, along the reference flux linkage trajectories, one-step MPTC is used to select the best voltage vector. The computational burden and dynamic performance of the proposed method are verified by experiments. [ABSTRACT FROM AUTHOR]

To achieve precise voltage value for modern model-based motor control strategies, an accurate voltage distortion compensation method for voltage source inverters is proposed in this paper. The voltage distortion principles of a mosfet-based inverter and an IGBT-based inverter are analyzed and compared. A graphical solution of compensating voltage error is proposed, all the voltage distortion factors are considered. A current observer is designed to overcome time delay, achieve precise current in each switching period for compensation. The proposed method is of high precision, intuitive, and easy to implement. The effectiveness of the proposed method is verified by experiments. [ABSTRACT FROM PUBLISHER]

This paper proposes an alternative strategy of finite-control-set model-predictive torque control (MPTC) to reduce the computational burden and the torque ripple and decouple the switching frequency from the controller sampling time. An improved discrete space-vector modulation (DSVM) technique is utilized to synthesize a large number of virtual voltage vectors. The deadbeat (DB) technique is used to optimize the voltage vector selection process, avoiding enumerating all the feasible voltage vectors. With this proposed method, only three voltage vectors are tested in each predictive step. Based on the improved DSVM method, the three candidate voltage vectors are calculated by using a novel algebraic way. This new strategy has the benefits of both the MPTC method and the DB method. The effectiveness of the proposed strategy is validated based on a test bench. [ABSTRACT FROM PUBLISHER]

This paper proposes a dynamic optimization strategy of finite control set-model predictive torque control for permanent magnet synchronous machines, which takes into account the inverter losses and machine losses simultaneously. In order to reduce the switching losses (or to optimize the switching sequence) of the inverter, a recognized and feasible constrain which considers the accumulated ON/OFF times of the switches is implemented. The machine losses are taken into account by utilizing an optimal stator flux reference. An alternative loss model control method is proposed to calculate the optimal stator flux reference, which combines the conventional maximum torque/ampere method and the conventional loss model control method. Furthermore, a discrete-time machine model is introduced, which can reduce the predictive error at relative low switching frequency. The key results are illustrated by a combination of simulation and prototype interior permanent magnet machine drive measurements. [ABSTRACT FROM AUTHOR]

This paper proposes a control strategy of finite-control-set model predictive torque control (FCS-MPTC) with a deadbeat (DB) solution for permanent-magnet synchronous motor drives. By using a DB solution, the process of selection of the best switching vector is optimized. The predicted DB voltage sector consisting of the desired voltage vector (VV) avoids the complete enumeration for testing all feasible VVs, which relieves the big calculation effort of the traditional FCS-MPTC method. The proposed system is experimentally carried out both in the steady state and in the transient state. [ABSTRACT FROM PUBLISHER]

This paper introduces two different novel designs of interior permanent-magnet synchronous machines with concentrated windings, which are attractive to a self-sensing control system. The new machines have some advantages: lower subharmonics of air-gap flux density and magnetomotive force and lower machine losses, including eddy current losses. The machines have been adapted for self-sensing applications by using a high-frequency (HF) injection method. The main machine parameters affecting the estimation accuracy are analyzed such as fundamental frequency saliencies, cross saturation, HF inductance, HF resistance, and harmonic distortion due to multisaliencies. The experimental results verify that the novel machines can reach very high performance with good self-sensing properties regarding the accuracy of the estimated position/speed of electric drives even without the multisaliency decoupling compensation method. [ABSTRACT FROM AUTHOR]