This paper introduces a proposed adaptive linear predictive model designed to enhance sustainability and energy efficiency in battery electric vehicles (EVs) equipped with permanent magnet synchronous motors (PMSMs). Central to the approach is a third-order generalized integrator (TOGI) flux observer, which provides real-time adaptation of the predictive model by accurately estimating motor parameters, enabling precise flux and torque control under varying operating conditions. The control scheme employs an active-set optimization algorithm to solve the quadratic programming problem efficiently, dynamically adjusting control inputs to optimize traction torque and speed tracking while minimizing battery energy consumption. The proposed method is rigorously compared against a published conventional model predictive control (MPC) approach. Comprehensive simulation studies and experimental tests confirm that the proposed model significantly outperforms the conventional MPC in terms of control accuracy, energy efficiency, and battery longevity. Specifically, results demonstrate up to 98% reduction in current tracking error, a 19% increase in battery operational life, and more than 40% reduction in DC source current consumption across different driving scenarios. The combination of accurate TOGI-based parameter adaptation and active-set optimization offers a robust, computationally efficient, and energy-saving solution, advancing the performance and sustainability of EV powertrain control systems.

This paper proposes a novel terminal sliding mode control for direct-thrust-controlled linear induction motor (LIM) control system based on feedback linearization control (FLC) to decrease the ripples of the thrust and flux. Meanwhile, the fast response and strong robustness of the thrust are also preserved compared with the conventional direct thrust control (DTC). By means of the FLC, the mathematic model of LIM is transformed into a linear model. The thrust and primary flux controllers can be separately designed. To overcome the sensitivity to the parameter variations of FLC, the full-order terminal sliding mode (FOTSM) control is proposed to ensure that the actual thrust and primary flux can track their references in finite time. The output signals of the FOTSM controllers are continuous where the chattering phenomenon is effectively attenuated. Comprehensive simulations have been carried out to demonstrate the superiority of the proposed method.

A full-order terminal sliding mode (FTSM) control strategy is proposed in this paper for the virtual synchronous generator (VSG) based inverter. VSG is designed for micro-grid to provide stable power to the grid or maintain stable operation in island state. The variable and nonlinear characteristics of micro-grid demand the voltage control scheme must satisfy with VSG power loop, and the control strategy should have strong robustness to resistant the external disturbance and parameters perturbance. FTSM can enhance the robustness and tracking speed of the system. Besides, the FTSM control strategy could reduce chattering problems caused by high-frequency switching. Simulations by MATLAB/Simulink show that the VSG algorithm combined with the FTSM control strategy can significantly enhance the output efficiency of the inverter, improve the output of the inverter, and deal with the load fluctuation.

The following topics are dealt with: power grids; invertors; control system synthesis; voltage control; switching convertors; distributed power generation; power generation control; electric current control; power convertors; DC-DC power convertors.

With the technology development of intelligent power generation and consumption, more and more electric vehicles (EVs), smart loads, and renewable energy are linked up to smart grids. In this paper, due to the great response ability of EVs, a large number of aggregate EVs are considered to improve the frequency response. From this point of view, for an EV-integrated smart grid with loads and renewable energy, a novel hierarchically adaptive control strategy is developed including both the primary controller and the EV controller when power mismatches happen. The sliding-mode primary controller is used to stabilize the frequency by operating power plants, while the EV controller is designed by using adaptive dynamic programming to deal with most of the frequency deviation. Simulation is validated on a benchmark smart grid by comparative studies to demonstrate the superior performance of hierarchically adaptive frequency control as well as the benefit of using EVs in the frequency regulation.

In this paper, one improved speed estimation method of linear induction motor (LIM) based on stator current observer is developed, of which the observer is deeply investigated and fully optimized. Then it discusses the estimation accuracy of observer influenced by different disturbances, and the effect of observer parameters on dynamic response is analyzed. Through comprehensive simulation, the speed tracking ability under some challenging operation conditions is investigated, which demonstrates that the proposed speed observer enjoys a good estimation capability.

A second-order integral flux observer (SOIFO-FLL) with dc component and harmonics attenuation capability is proposed for PMSM sensorless control in this paper. Due to the nonzero integral initial value, parameter mismatch, converter nonlinearities and detection errors, the estimated rotor flux by the conventional methods, pure integrator and low-pass filter (LPF) suffer the dc component and harmonics. And a novel rotor flux estimation method, SOIFO-FLL is proposed on basis of the second-order generalized integrator (SOGI) structure. Combined with the frequency-locked loop (FLL), the dc and high-order harmonics of the estimated rotor flux can be removed by the SOIFO. Lastly, the rotor position are exacted accurately by a quadrature normalized phase locked loop (Q-PLL). Simulations and experimental results verify the excellent performance of the proposed SOIFO-FLL based rotor flux observation and sensorless control strategy.

The ship shaft power generation system based on a stand-alone brushless doubly-fed induction generator (BDFIG) have demonstrated excellent saving-energy performance. This paper presents a new control scheme of the stand-alone BDFIG for supplying unbalanced loads in the ship shaft power generation system. The positive-and negative-sequence components of the unbalanced power winding (PW) voltage caused by the unbalanced loads are regulated separately. Comprehensive experiments are carried out on a prototype BDFIG by employing the conventional and proposed control schemes. The experimental results verify the good performance of the proposed control scheme.

To achieve good steady-state performance and quick dynamic response, one model predictive current control (MPCC) method is proposed in this paper to replace the traditional proportional-integral (PI) controller to regulate the control winding (CW) current of brushless doubly-fed machine (BDFM) for stand-alone power generation system. The MPCC is developed based on the unified reference frame dq model of the BDFM. Simulations under several typical conditions are carried out to verify the effectiveness of MPCC. It is proven that MPCC can get a better CW current response than PI controller and can produce better effects on the output voltage of power winding (PW). Besides, MPCC is simpler than PI current control loop, because no parameters need to be tuned for MPCC.

The brushless doubly-fed induction generator (BDFIG) shows commercial potential for the wind-power generation and ship shaft power generation due to its brushless operation as compared with doubly-fed induction generator. This paper proposes an improved vector control scheme oriented on the power winding flux reference frame to achieve stable stand-alone operation. To improve the dynamic performance of the load disturbance, the feed-forward compensation from the power winding (PW) current is also introduced. Simulation results on steady state and transient state have been carried out to verify the control scheme.

Due to the current constraint of linear induction machine (LIM) and voltage constraint of inverter, the output thrust of LIM is limited. So, in order to make LIM output thrust as large as possible within current and voltage limit, firstly, the maximum thrust per ampere (MTPA) is used to achieve maximum thrust with limited current in low speed. Secondly, with the speed of LIM increasing, the voltage limit of inverter has to be considered by the method of field-weakening. And similar to the concept of MTPA, the maximum thrust per volt (MTPV) is deduced for achieving maximum thrust within the voltage constraint of inverter. Finally, the deadbeat control method is applied to LIM for high tracking performance, and both simulation and experiments demonstrate the effectiveness of this proposed control strategy.

The drive performance of permanent magnet synchronous motor (PMSM) can be deteriorated due to various disturbances. In this paper, the problem of speed control for a PMSM system with parameter uncertainties is investigated. A new control algorithm based on nonsingular terminal sliding mode control (NTSMC) is proposed, where the controller is developed for speed regulation. Compared with conventional strategies, this new controller provides improved performance for speed regulation of PMSM when subject to parameter uncertainties, in that it achieves fast dynamic response and strong robustness. Simulation studies are conducted to verify the effectiveness of this proposed method.

Due to the difference in the working condition and operating mode, permanent magnet (PM) traction motors design concept significantly differs from the traditional industrial motor. Optimization design of the PM traction motor with wide high efficiency range for electric vehicle (EV) application is investigated in this paper. Firstly, the basic design principle and dimension constraint are analyzed and determined. Secondly, the split ratio, the angle between the V-type magnet, slot depth and tooth width are optimized by finite element analysis (FEA) under different working conditions. Furthermore, simulations implemented on the traction motor demonstrate that the wide high efficiency range can be obtained by optimization. Finally, comprehensive experiments have been implemented on a traction motor prototype to validate the feasibility of the traction motor design scheme.

This paper mainly studies the speed control for a permanent magnet synchronous motor system. The relationship between the reference quadrature axis current and the speed output is approximately considered as a second-order model. Based on this second-order model, a composite control strategy is adopted, where a continuous sliding mode controller is designed for the speed regulation without chattering and a disturbance observer is introduced as a compensator to resist disturbances and to reduce control gains. Simulation results have been presented to illustrate that the proposed method has good responses to reference speed signals with torque load disturbances.

This paper analyzes the rotor magnetic potential distribution of one large turbo generator both in normal and rotor inner winding short-circuit fault states. By the influence of short fault, the second harmonic current of the stator winding will induce one half and one two-third harmonic currents to the stator winding and the rotor winding respectively. Furthermore, it also analyzes theoretically the effect of inter-turn short circuit on characteristic parameters, which include the stator current, the stator voltage, the rotor current, the rotor voltage, and the active/reactive power. Then a method is proposed to predict or identify different practical faults in details, which is on the base of the relative variation laws of those characteristic parameters varying with the severity of the rotor inter-turn short circuit fault. The fault criterion of rotor inter turn short-circuit on-line identification has been investigated, which can estimate different types of faults. Finally, theoretical analysis based on simulation in Simulink/Matlab is carried out by using the dynamic short-circuit model of large turbo generator units. This paper could give good guidance for the judgment of the rotor inner winding short-circuit fault of large turbo generator by the right choice of characteristic parameters.

In this paper, a linear-prediction maximum power point tracking (MPPT) algorithm for photovoltaic (PV) power generation is presented. This allows rapid tracking without step-size reference. The new methodology has two parts: linear prediction and error correction. The first part estimates the maximum power point (MPP); this improves the MPPT response speed. The second part calibrates the error after the linear prediction; this enhances the calculation accuracy which leads to a faster MPP convergence. Theoretical analysis and simulations are put forward to validate the feasibility of the linear prediction method. Convergence, error correction, and steady and dynamic state evaluations are made. The results show that the algorithm can work effectively and have the advantages of fast response and high efficiency when compared to the Perturbation and Observe (P&O) algorithm.

In order to increase the efficiency of photovoltaic (PV) system as much as possible, the maximum power point tracking (MPPT) technology has been paid more attention during the past decades. Among all the maximum power point tracking strategies, the variable step-size MPPT algorithm is widely employed due to its high tracking accuracy and fast speed. However, most of the existing methods are based on perturbation and observation method (P&O), and some essential parameters such as maximum step size and scaling factors are difficult to decide very accurately, due to the fact that the slope of power versus voltage (dP/dU) is asymmetric at the maximum power point (MPP). In order to avoid this defect, a novel variable step-size MPPT algorithm is proposed in this paper, which could adjust the step size online intelligently. Compared with other variable step-size MPPT algorithm, the new method does not need to calculate the maximum step size and speed factor. It can provide a simple and effective way to ameliorate both dynamic and steady state response characteristics. Plenty of theoretical derivation and comprehensive simulation results demonstrate that the new algorithm is much faster and more accurate than those traditional fix step-size methods.

The doubly salient permanent-magnet synchronous machine (DSPMSM) is a new type of brushless machine with permanent magnet locating in its stator pole. Compared with other traditional PMSMs, it can offer advantages of high power/torque density, simple mechanical structure and wide speed range for high speed cruising, which is attractive to the applications of wind energy, plug-in hybrid electrical vehicle, etc. However, due to the nature of salient poles in both the stator and rotor, the DSPMSM suffers from severe torque and flux ripples for its variable magnetic circuits and equivalent air gap length. The conventional switching-table-based direct torque control (DTC) receives increasing attention for its merits of quick dynamic response, strong robustness and simple control structure. However, during the conventional DTC algorithm, large ripple of both torque and air gap flux often occurs for its hysteresis control based on Bang-Bang modification principle. This paper presents one improved strategy to reduce the torque ripple of DSPMSM drive system by the help of model based predictive torque control (MPTC), which is an improved algorithm in the base of conventional DTC. Similar as the traditional MPTC strategy, the new algorithm still requires one completely decoupling control scheme. By selecting the best voltage vector to satisfy the demands of torque and flux, the new method can obviously reduce both torque and flux ripples. Comprehensive simulation results are finally presented to validate theoretical analysis, and further experiments will be available in the near future.

This paper investigates the lightning over-voltage process of a 1000 kV ultra-high voltage(UHV) gas insulated switchgear(GIS) substation by the help of one electromagnetic transient simulation software, Electromagnetic Transients Program-Alternative Transients Program (ATP-EMTP). Taking the near lightning stroke for example, the simulation model is built with a substation, some incoming lines and their relevant line terminals. Firstly, it studies different influences of various substation operation modes, line voltage, and impulse grounding resistance, etc. Secondly, in order to identify the over-voltage distribution and variation of the electrical substation equipments (mainly transformers), it studies the over-voltage influence generated by lightning invasion wave in the whole system. Finally, based on comprehensive simulation and theoretical analysis, some suggestions are proposed to restrict the lightning over-voltage.