Abstract—This paper presents a speed-sensorless approach for Direct Predictive Speed Control (DPSC) of Permanent Magnet Synchronous Motors (PMSMs). By eliminating the traditional cascade control structure, the proposed method enables integrated control of both electrical and mechanical systems under a single predictive law, witch can enhance control performance and operational robustness. Additionally, speed-sensorless control reduces the cost of the electric drive while contributing to increased system reliability. The proposed approach includes a cascade observer system composed of three key components: a Sliding Mode (SM) Back-Electromotive Force (BEMF) observer for estimating stator currents and BEMFs, a secondary BEMF observer for speed and rotor position estimation, and another SM observer for load torque estimation. The proposed observer is validated and compared to Extended Kalman Filter approach. Simulation results demonstrate that this cascade observer effectively tracks speed and load torque. While the proposed observer shows some limitations at very low speeds due to its BEMF-based nature, it generally offers robust performance across a range of operating conditions. The proposed drive system is tested in different operating conditions, and finally, satisfactory control performance is achieved overall.

This paper proposes a sensorless control strategy for non-sinusoidal permanent magnet synchronous machines (PMSM) integrating a Super-Twisting Sliding Mode Observer (STA-SMO) with a Dual Second-Order Generalized Integrator and Positive Sequence Detector (DSOGI+PSD). The non-sinusoidal back-electromotive force (BEMF) in such machines introduces harmonic distortion, which degrade conventional estimation methods. The STA-SMO robustly estimates the BEMF with minimized chattering through finite-time convergence, while the DSOGI+PSD adaptively isolates the fundamental component by suppressing harmonics. A Phase-Locked Loop (PLL), synchronized with the filtered BEMF, dynamically extracts rotor position and speed. Simulation results demonstrate precise speed estimation and oscillation-free position tracking under steady-state and dynamic conditions. The proposed scheme effectively mitigates harmonic interference, enabling reliable sensorless control for PMSMs with non-sinusoidal BEMF.

This study presents a methodology for determining the efficiency of electric motors and the thermal behavior of inverters, with a focus on the associated losses. An integrated simulation approach was developed, incorporating JMAG motor models, PLECs software for loss calculation, and Simulink for comprehensive system simulation. The methodology was validated through a vehicle’s driving and start-up cycles, producing efficiency maps across various operating conditions, including different switching frequencies and bus voltage levels. The results highlight the broad applicability of this simulation methodology to various types of machines and semiconductor technologies. This approach is particularly effective for accelerating the development of traction inverters, providing valuable insights for optimizing system performance.

This paper presents an approach to estimating the junction temperature of SiC MOSFETs in three-phase inverters, crucial for electric vehicle applications. This study carries out the conversion process from Foster to Cauer thermal networks, which enables a space-state representation with intermediate temperature states, such as: internal module and module case temperatures. A Luenberger-type state observer is used to estimate the switch junction temperature. The proposed method demonstrates enhanced robustness and accuracy compared to conventional open-loop thermal models. Simulation results, validated through PSIM software, illustrate the effectiveness of the observer in maintaining temperature estimates within safe operational limits even with incorrect initial states. The findings underscore the potential for improved reliability and lifespan prediction of semiconductor devices in harsh operating conditions.

This paper presents a high frequency linear model for low-speed sensorless control of interior permanent magnet synchronous motor (IPMSM) drives. The proposed model uses a β-axis high frequency signal injection in order to model a new high frequency flux variable, which has similar properties to the standard electromotive force (EMF) used for high-speed sensorless control. Through the proposed model, the well established observer techniques from the literature can be used for rotor position and speed estimation. Thus, the low-speed sensorless scheme can be designed in similar form as the high-speed EMF based methods. Here, position and speed estimation are performed by an adaptive full-order observer, which is designed through a pole placement method and its stability constraints are investigated. Simulation results validate the proposed high frequency linear model and adaptive observer design method under sensorless vector control.

Proper current control is essential in SRM drives in order to ensure adequate reference tracking and torque ripple reduction when using current profiling techniques. In this context, this paper proposes a PWM super-twisting sliding mode current controller for switched reluctance motors with a fixed-gain structure. The approach presents a model-free structure, not requiring model information on implementation. The PWM implementation ensures a fixed switching frequency and the fixed-gain approach leads to a simple control structure, not demanding any sort of gain lookup tables. The complex task of gain design for super-twisting controllers is solved in this paper by means of an optimization-based design methodology, using the sum of the squared error as a cost function. The proposed technique is compared to a higher sampling hysteresis controller in terms of current and torque root-mean-square error. Simulation results are presented, showing that the proposal achieves a performance comparable to a higher sampling hysteresis controller.

This paper proposes a procedure to optimize the firing angles of a switched reluctance generator via the particle swarm optimization algorithm. This aims to ensure performance with a balance between high energy efficiency and reduced torque ripple. The technique is intended for SRGs operating in the current-controlled region, below base speed. The proposed procedure is compared with a traditional fine grid approach in order to show the significant reduction in computational effort. Simulation results are provided, demonstrating that a performance with a balance between reduced torque ripple and increased efficiency is achieved.

This paper describes a simple optimum carrier-based geometrical modulation for both NPC and T-Type inverters. The current that flows through the midpoint of the DC bus can be controlled in order to balance the capacitor voltages for a wide range of modulation indexes and power factors. This was accomplished by adding to the reference phase voltages a common-mode voltage vo,obtained by solving an optimization problem. In order to validate the good performance of the proposed modulation strategy, experimental results with Typhoon HIL are presented for NPC and T-Type inverters for different modulation indexes and power factors.

This paper presents a rotor speed estimation technique based on a Luenberger observer for sensorless speed control of a synchronous reluctance motor (SynRM). The model of the SynRM is presented, both on the synchronous rotating frame as well as in the stationary rotating frame. The observer design is presented, along with the extended state space model, used to obtain both actual and observed αβ currents and αβ electromotive force (EMF). The field oriented control structure used in this paper is shown. Lastly, experimental results are presented in order to verify the effectiveness of the sensorless control strategy along with the convergence of the observed variables and estimated speed.

This paper presents the design of a sliding mode controller (SM) applied to the speed control of a switched reluctance motor. The SRM has a non-linear model, given its constructive nature and drive operation. The mathematical modeling is presented, taking into account the operation under saturation as well as a simplified model, where the inductance is considered only position dependent. The converter used to drive this machine is presented, as well as its principle of operation, dependent on the switching angles. Simulation and experimental results are presented in order to demonstrate the effectiveness of the proposed control strategy.

This study proposes a sensorless decoupled current control method applied to Internal Permanent Magnet Synchronous Motor (IPMSM) drives via vector control and disturbance observer. The IPMSM presents the unavoidable and unmeasured disturbances, parameter variations and coupling between the axes. The coupling terms of the IPMSM are modeled as disturbances and these observed disturbances are used in the control law. Moreover, a model reference adaptive system with sliding mode technique is used to estimate the rotor speed. As result, a decoupled current control system and a sensorless rotor speed control are achieved. Experimental results are presented and they show the effectiveness of the proposed scheme.

This paper presents the design of a sliding mode (SM) technique applied to output voltage control of switched reluctance generators. From the tracking error, the SM controller sets the reference to an hysteresis regulator. In order to adjust the phase currents around this reference, the regulator changes the state of the asymmetrical half bridge switches during the excitation mode. A model based on experimental data is used to simulate the system. Simulation results are presented, from which it is possible to validate the proposed scheme.

This paper presents a current control method applied to permanent magnet synchronous motors using sliding mode controller and disturbance observer. The current control is carried out at dq synchronous reference frame. The proofs of stability are developed from the Lyapunov analysis requirements. A sliding mode rotor speed observer is combined with the proposed current control scheme. Simulations results are presented to validate the proposed technique.

This paper proposes a multi-loop controller for current control of a grid-connected inverter with an LCL-filter. The inner loop uses the converter current error as the sliding surface in a Sliding Mode Control (SMC) approach. The model obtained allows the application of an outer Model Reference Adaptive Control (MRAC) for the tracking of the grid current in a robust fashion with disturbance rejection. Simulation results are presented to validate the theoretical analysis.

This paper presents a decoupled current control system applied to induction machine drives via sliding mode control and disturbance observer. The current control of induction motor is carried out with indirect field orientation rotating at dq synchronous reference frame. The coupling terms are modeled as disturbance and the observed disturbance is used in the control law. Moreover, an algorithm aiming the rotor speed estimation based on magnetizing current estimation and sliding mode approach is presented. As result, a sensorless control system with decoupling of stator current is proposed. Experimental results are presented aiming to verify the system performance.

This paper proposes a current controller for grid tied Voltage Source Inverter (VSI) via a LCL filter using discrete-time Sliding Mode Control (SMC) in a multi-loop framework. The inner loop is implemented by the SMC with reference generated by an outer controller for the VSI side current. The tracking of the current entering the distribution network is ensured by a outer controller with a derivative + ressonant structure (for compensation and disturbance rejection with reference tracking). Simulation and experimental results are presented to validate the good performance of the proposed control strategy.

Vector control has improved the performance and energy efficiency in SPIM drives. However, high current and torque pulsations are produced by winding asymmetry of SPIM. This paper proposes a decoupling scheme to reduce the current and torque pulsations and improve the performance of vector control. A stator current observer is used to estimate the coupling signals, which are compensated by control law. This method is an alternative to improve the performance of single-phase induction motor used in hermetic refrigeration systems. The thermal efficiency of refrigeration system can be improved by the variable speed operation and the advantages of robustness and low-cost of single-phase induction motor can be maintained.

This paper presents the development of discrete-time sliding mode rotor speed and rotor flux observer applied to induction machine drives. The conditions for the discrete-time sliding hyperplane existence are discussed. The sliding hyperplane are formed by the stator currents estimation errors and by the observed rotor fluxes. Simulation and experimental results using DSP TMS320F2812 are presented aiming to verify the effectiveness of the proposed scheme.