The development of an output feedback controller (OFC) for a hybrid electric vehicle (HEV) is presented in this paper. The light-weighted DC motor-driven model of HEV is considered which includes a high degree of nonlinearity as uncertainty. The nonlinearity, uncertainty, and non-assessable states of the HEV plant model are estimated using a state and uncertainty estimator (SUE). The proposed controller is designed for speed control of the motor for optimal operation of HEV to meet the model range specifications based on SUE and output feedback. A suitable reference trajectory has been obtained for a smooth tracking response of motor speed. The uncertainty considered in this paper is significantly large and does not require satisfying the constraints (bounded/finite derivative to be 0, etc.). The estimator-based OFC is synthesized for the attenuation of the effect of nonlinearity and uncertainty to stabilize the HEV. For the analysis of stability, sufficient conditions for the synthesis of OFC have been obtained using the Lyapunov theory and linear matrix inequality approach. The simulation study has been done to show the efficacy of the proposed OFC control scheme. The performance of the proposed scheme has been analyzed by a comparative evaluation with the existing control schemes in terms of tracking performance, lesser tracking error, bounded control input under actuator limit, attenuation of the effect of nonlinearity and uncertainty, etc. Finally, it is concluded that the HEV performance using the proposed control scheme has been enhanced in comparison with existing schemes.

The current measurement offset errors (CMOEs) raise concerns regarding the performance degradation of interior permanent-magnet synchronous motor (IPMSM) drive system. Considering this, a detailed analysis of the impact of CMOE is conducted in this paper, and a compensation strategy is proposed. Based on the established dual-inertia model of the IPMSM drive system, the effects of CMOE on electromechanical coupling resonance are analyzed. Furthermore, the CMOE compensation scheme based on an improved adaptive observer is designed to eliminate these adverse effects. In the proposed compensation scheme, adaptive gains are designed to ensure effective compensation performance at different speeds. In addition, the proposed compensation scheme is decoupled from vector control and has a relatively small impact on the control performance of the motor. Finally, extensive tests are conducted to validate the effectiveness of the proposed method.

With the increasing penetration of renewable energy, the inertia deficiency in power systems has become more severe. Existing wind-storage joint frequency regulation (FR) strategies exhibit significant limitations in coordinated control capability and energy storage system (ESS) lifetime management. To address these challenges, this paper proposes a hierarchical control strategy for coordinated optimization of wind farms (WF) and hybrid energy storage systems (HESS). First, a multi-constraint regulation mechanism is established to dynamically switch power operation curves by assessment of frequency and the operating states of wind turbine generators (WTG) and HESS. Second, a smooth transition algorithm is designed to suppress the frequency secondary drop (FSD) by controlling the dynamic trajectory of power curves. For HESS, a dual-layer optimization framework combining model predictive control (MPC) and fuzzy logic control (FLC) is employed: the upper layer performs rolling optimization of control objectives, while the lower layer utilizes FLC to allocate power between the supercapacitor and the battery, adjust the operation curve, and optimize the battery charging strategy based on the state of charge (SOC) and frequency feedback. Simulation results demonstrate that the proposed strategy reduces frequency deviation by 60%-80% and decreases battery lifetime loss by more than 20% under various operating conditions.

In this paper, a family of back-to-back three-level power factor correction (BT-PFC) converters is proposed. A bi-directional switch unit is cascaded or embedded in the midpoint between the bridge arm and the two capacitors of the back-to-back PFC to achieve three output voltage levels during the frequency harmonic content and lower the equivalent switching frequency. Firstly, the derivation methods and circuit characteristics of the proposed topologies are analyzed and compared, and one of the topologies is chosen as an example to describe its operating principle. Further-more, decoupling closed-loop control and modulation technology of the proposed BT-PFC converter are analyzed in detail. Finally, an experimental prototype with an input of 220V/50Hz and a rated output of 1kW/400V is designed based on the BT-PFC-VI circuit. The experimental results show that the proposed single-phase BT-PFC has higher efficiency and flexibility is verified.

The rapid growth of nonlinear and unstable load penetration into the grid network has a detrimental impact on the grid system’s ability to deliver high-quality power. Moreover, it results in a situation where it becomes difficult to maintain high-quality power in the distribution sectors. As a result, it is exceedingly challenging to maintain a high standard of power quality (PQ) in a distribution system. To improve the quality of grid voltage a series compensating filter called dynamic voltage restorer (DVR) is used in this suggested work. An adaptive zero-attracting quaternion-based least mean square (AZQLMS) approach is suggested to extract the fundamental quantity from the polluted voltage of the grid. An optimization technique, frilled lizard (FL) inspired by nature, is employed to estimate the gains of the fractional order proportional integral derivative (FOPID) controllers used in this control algorithm for DC link voltage stabilization. Compared to the marine predator (MP) optimizer, the proposed Frilled Lizard algorithm demonstrates enhanced capability to escape from local entrapment with quicker convergence and also reduces the complexity of manual tuning effort simultaneously. From the perspectives of DC link time response characteristics under transitory scenario, control technique, and the range of compensated voltage, the enhanced DVR’s principle has been examined. By minimizing the voltage issues and the voltage total harmonic distortion (THD) at the connection point below 5%, both controllers were able to restore the voltage magnitude. MATLAB/Simulink with experimentation work is utilized to analyze the efficacy of the suggested approach. It is evident from the information that the AZQLMS and FL-FOPID successfully control the distribution grid’s voltage.

In order to address the issue of mutual inductance variation in dynamic wireless power transfer systems for electric vehicles, which leads to significant fluctuations in system output, an edge-enhanced stepped coil structure is proposed to improve the system’s anti-offset performance. Firstly, a model of the edge-enhanced stepped coil structure has been constructed, and the characteristics of mutual inductance variation for this structure have been analyzed. Secondly, a method for calculating mutual inductance in a stepped coil structure is proposed based on the Biot-Savart law. Then, based on the proposed method for calculating mutual inductance in stepped coils, the parameters of the edge-enhanced stepped coil structure are optimized according to the principle of minimizing fluctuations in mutual inductance. Additionally, a magnetic core structure that aligns with the coil’s characteristics is designed to enhance both mutual inductance and the coil’s resistance to offset performance. Finally, a 500W experimental prototype has been constructed. The experimental results show that the mutual inductance fluctuation rate of the edge-enhanced stepped coil does not exceed 5% when the Y-axis direction is offset by 50% (362mm) of the outer diameter of the transmitter coil. The transmission efficiency of the system is as high as 93.92%, and the fluctuation rate of the output current is less than 5%.

A continuous-control-set predictive control strategy is proposed for the phase-shift-modulation dual-active-bridge topological cluster. This strategy addresses two critical issues: high sensitivity to model parameters and sampling noise in traditional model predictive control. The steady-state error is analyzed in detail, considering model parameters and modeling methods. We establish a unified and simplified predictive model that is suitable for different dual-active-bridge topologies, reducing dependence on model parameters and computational burden. To mitigate sensitivity to sampling noise, we design a noise tolerance enhancement strategy by redefining a coefficient in the simplified model. This strategy expands the noise tolerance range while maintaining excellent dynamic performance, low system cost, and computational burden. The proposed control strategy is verified by using an experimental platform with TMS320F28379D as the core controller. Results show that our strategy effectively reduces sensitivity to model and noise while ensuring excellent dynamic performance compared to traditional model predictive control. The strategy is universal and significantly reduces the computational burden.

As renewable energy integration reduces grid strength, energy storage virtual synchronous generator (VSG) control becomes critical for grid support. However, power quality challenges arise from nonlinear loads and background harmonics in distribution networks. This study addresses energy storage VSG’s power quality limitations by proposing a sensor-free selective control strategy to optimize point of common coupling (PCC) voltage or grid current without altering existing VSG structures. An odd-order repetitive control technique reshapes harmonic impedance, supported by a grid-VSG harmonic impedance model. Two supplementary loops selectively suppress voltage/current harmonics, enhancing power quality management without external sensors or harmonic extraction modules. The method eliminates hardware additions while resolving VSG harmonic issues in micro-grids and large grids. Results demonstrate significant improvements in harmonic mitigation, enabling energy storage VSG systems to partially replace active power filters (APFs). This approach offers a cost-effective solution for harmonizing renewable integration with grid stability, broadening VSG applicability. Key innovations include dual-loop adaptive harmonic suppression and impedance reshaping through modified repetitive control, advancing sensor-less power quality enhancement in modern power systems. The strategy effectively balances grid support functionality with harmonic management, facilitating scalable renewable energy adoption.

A DC microgrid cluster (DCMGC) is a networked power grid that consists of multiple small-scale DC microgrids (DCMGs), and every single DCMG (sub-grid) can be composed of multiple heterogeneous units, e.g., distributed energy resources like photovoltaic (PV) and wind turbine (WT), energy storage systems (ESS), and local loads. The DCMGC is such a complex network with multiple control objectives that requires control at both system-level and sub-grid level, which suits well with model predictive control (MPC) algorithms. However, the MPC suffers from the high computation burden, especially dealing with complex control plant models like DCMGCs. In this paper, an event-triggered predictive function control (ET-PFC) is proposed for power management of DCMGCs, maintaining excellent control performance of PFC algorithm while saving computing resources in the control process. Further, a universal low-cost microcontroller (STM32) solution is presented for implementation of the ET-PFC scheme and a low-voltage DCMGC laboratory prototype that consists of three DCMGs (six converters) is built to validate the controller implementation by hardware experiment results.

In this paper, a novel low voltage and current stress zero voltage transition (ZVT) cell is proposed for a family of non-isolated DC-DC converters. By adding a current transfer circuit composed of an auxiliary switch, a diode, two capacitors, and two inductors to the traditional DC-DC converters, the proposed converters achieve zero voltage switching (ZVS) condition for active switches, and alleviates the reverse recovery problem for two diodes. Moreover, with the proper design of the auxiliary circuit, the voltage spikes during the switching process are significantly reduced. And the proposed ZVT cell only introduces low voltage stress but avoiding any additional current stress on the power semiconductor device. The operating principle and performance analysis of the proposed Boost converter are given in detail. The experiment from a 2-kW laboratory prototype at 100 kHz switching frequency has been carried out to validate the theoretical principles. The experimental results show that the proposed Boost converter has the advantage of simple structure and the peak efficiency is found to be 98.76%.