Self-commissioning of interior permanent- magnet synchronous motor drives with high-frequency current injection

In this paper, a simple and robust method for parameter estimation at rotor standstill is presented for interior permanent magnet (IPM) synchronous machines. The estimated parameters are the stator resistance through dc test, the dq inductances using high-frequency injection, and the permanent magnet flux by means of a closed-loop speed control maintaining rotor stationary. The proposed method does not require either locking the rotor or additional/special power supplies. The validity of the suggested method has been verified by implementation on two IPM motor prototypes. Finally, the estimated parameters have been compared against results obtained through finite-element simulations and with machine magnetic characterization, separately performed, to validate the method's effectiveness. Saturation and cross-saturation effects are taken care of through amplitude modulation and cross-axis current application, respectively

Energy Efficient Speed Control of Interior Permanent Magnet Synchronous Motor

In this chapter, methods for the structural realization of a speed control system for the interior permanent magnet synchronous motor (IPMSM) using the “maximum torque per ampere” (MTA) and “maximum torque per volt” (MTV) optimal control strategies are considered. In the system in constant torque region, is a technique for adapting the speed controller to the presence of the reactive motor torque component, which improves the quality of the transient processes, is proposed. It is also recommended to approximate the dependence of the flux-forming current component on the motor torque by the “dead zone” nonlinearity, which will simplify the optimal control algorithm and avoid solving the fourth-degree algebraic equation in real time. For the speed control with field weakening technique, a novel system is recommended. In this system, the control algorithms are switched by the variable of the direct stator current component constraint generated in accordance with the MTA law: the upper limit is calculated in accordance with the “field weakening control” (FWC) strategy, and the lower limit in accordance with the MTV strategy. The steady-state stator voltage constraint is implemented through the variable quadrature stator current component limitation. The effectiveness of the proposed solutions is confirmed by the simulation results

Nonlinear Direct Torque Control of Interior Permanent Magnet Synchronous Motor Drive

This paper presents a nonlinear direct torque control (NDTC) strategy of interior permanent magnet synchronous motors (IPMSMs) for electric vehicle (EV) propulsion. The proposed NDTC scheme applies a nonlinear model of IPMSM to dynamically determine the optimal switching states that optimize the EV drivers’ decision to reduce the workload. Moreover, the proposed NDTC method has a simple control structure and can explicitly handle system constraints and nonlinearities. The performance evaluation is conducted via a prototype IPMSM test-bed with a TMS320F28335 DSP. Comparative experimental results provide the evidence of improvements of the proposed NDTC strategy over the conventional DTC strategy by indicating a fast torque response and an accurate speed tracking even under rapid speed change conditions

Optimization and analysis of interior permanent magnet synchronous motor

The optimization of the interior permanent magnet synchronous motor and analysis of operating characteristics of optimized models in comparison to the starting model is the objective of this paper. Optimization is done by optimetrics analysis i.e. four motor parameters are selected and varied within certain boundaries allowing out of each combination of these varied parameters, new motor models the be obtained. The best candidates i.e. models with respect to the efficiency and cogging torque are selected. The optimized models have improved efficiency and cogging torque with respect to the starting model

Linearizing speed control and self-commissioning of interior permanent magnet synchronous motor

В роботі синтезовано лінеаризуючий зворотнім зв'язком алгоритм відпрацювання заданих траєкторій кутової швидкості і прямої компоненти струму статора явнополюсного двигуна зі збудженням від постійних магнітів. Також запропоновано триетапну процедуру початкової ідентифікації параметрів синхронного двигуна для реалізації функції "self-commissioning". Синтезовані адаптивні алгоритми дозволяють послідовно оцінювати всі сім параметрів синхронного двигуна в умовах сформованих тестів. Ефективність синтезованих алгоритмів підтверджено результатами математичного моделювання.Vector-controlled Interior Permanent Magnet Synchronous Motor (IPMSM) is dominating in high-precision speed/position tracking applications. Precise knowledge of the six motor parameters and load torque is required for the control implementation. The problem of IPMSM parameters identification has still not been fully solved even for "self - commissioning" procedure despite of the significant amount of research activities in the field. In this paper a new speed tracking control algorithm with decoupling of the direct current component and angular velocity control is presented. Due to this feature it is possible to freely regulate the direct current component in order to achieve more efficient control without degradation of the speed dynamics. A novel three stages "self - commissioning" procedure is proposed for IPMSM parameters identification. For each testing stage the adaptive algorithms are designed using the second Lyapunov’s method. First two stages are based on adaptive current control. The mechanical parameters are estimated by adaptive speed observer. Presented algorithms allow to estimate all seven IPMSM parameters under test conditions consistently.Simulation results proof the effectiveness of the proposed procedure

A globally exponentially stable position observer for interior permanent magnet synchronous motors

The design of a position observer for the interior permanent magnet synchronous motor is a challenging problem that, in spite of many research efforts, remained open for a long time. In this paper we present the first globally exponentially convergent solution to it, assuming that the saliency is not too large. As expected in all observer tasks, a persistency of excitation condition is imposed. Conditions on the operation of the motor, under which it is verified, are given. In particular, it is shown that at rotor standstill---when the system is not observable---it is possible to inject a probing signal to enforce the persistent excitation condition. {The high performance of the proposed observer, in standstill and high speed regions, is verified by extensive series of test-runs on an experimental setup

Towards an improved energy efficiency of the interior permanent magnet synchronous motor drives

This paper investigates the possibility of energy efficiency increase in the drives with high speed permanent magnet synchronous motors. The losses are decreased by the proposed procedure, i.e. proper allocation of the available stator current capacity to the direct and quadrature current components. The approach provides increased energy efficiency by varying the ratio between copper and iron losses. [Projekat Ministarstva nauke Republike Srbije, br. III042004

Control Techniques for an Interior Permanent Magnet Synchronous Motor of an Electrified Vehicle

A system and method for controlling an interior permanent magnet sychronous motor (IPMSM) are presented. In an exemplary implementation, phase current ripple estimation techniques are utilized for variable frequency switching pulse-width modulation control of the IPMSM. In one implementation, the method includes controlling a three-phase inverter based on an initial switching frequency to generate a three-phase alternating current (AC) voltage for the IPMSM. Transformed voltages are determined in a rotating reference frame based on the three-phase AC voltage in the stationary reference frame. Current ripples are determined in the rotating reference frame based on the transformed voltages. Phase current ripples are determined in the stationary reference frame based on the current ripples in the rotating reference frame. A modified switching frequency for the three-phase inverter is determined based on the initial switching frequency and the phase current ripples. The three-phase inverter is then controlled based on the modified switching frequency

Optimization and analysis of an interior permanent magnet synchronous motor

This paper aims to optimize an interior permanent magnet synchronous motor and analyze the operating characteristics of optimized models compared to the starting model. The optimization is done by optometric analysis, i.e., four motor parameters are selected and varied within certain boundaries, allowing new motor models to be obtained from each combination of these parameters. The best candidates are selected, i.e., models concerning the efficiency and cogging torque. The optimized models have improved efficiency and cogging torque compared to the starting model