Frequency Regulation In AC Microgrid Research Articles

A Fully Resilient Cyber-Secure Synchronization Strategy for AC Microgrids

This letter focuses on resilient synchronization in networked ac microgrids under cyber-attacks, where attackers aim to desynchronize converters by injecting bounded false data to communication and control channels. To this end, a resilient cooperative control framework for the secondary frequency regulation in ac microgrids is developed. The proposed resilient distributed control strategy achieves synchronization regardless of the existence of cyber-attacks. Moreover, it offers the maximum level of resilience, i.e., it guarantees resilient synchronization even if all distributed generation units in microgrids are subject to cyber-attacks. Theoretical analysis and verification case studies are carried out in order to demonstrate the advantages and performance of the proposed resilient cooperative control.

Enhancement of Frequency Regulation in AC Microgrid: A Fuzzy-MPC Controlled Virtual Synchronous Generator

Electrical energy storage (EES) with a virtual synchronous generator (VSG) method is used widely for power fluctuation compensation in renewable energy microgrid systems. In the traditional VSG method, the inertia moment and damping coefficients usually remain constant. When dealing with large load variations, this method may cause obvious system frequency deviations and exceed the standard limit (e.g., IEEE Std 1547-2018). This paper proposes a novel control method combining fuzzy control with a model predictive controller (MPC) to solve this problem. The new method was applied to VSG. The virtual inertia and damping coefficient of VSG are on-line adjusted by a fuzzy controller, so that the regulation capability of the swing equation can be substantially utilized. The optimal rated power of VSG was modified using the MPC method, which further strengthens the EES support for power needs. The system frequency performance can be enhanced effectively under joint control. The simulation and experimental results further demonstrated the effectiveness of the proposed method.

Adaptive Power Point Tracking Control of PV System for Primary Frequency Regulation of AC Microgrid With High PV Integration

With the increasing integration of PV generation in AC microgrids, it is challenging to keep the stability of system frequency due to the intermittent and stochastic nature of PVs. Thus, in order to reduce the investment and maintenance costs of storage systems, the electric utility has shown increasing interest in calling on PVs to provide frequency regulation services. In this paper, a novel sliding mode control (SMC) based adaptive power point tracking (APPT) control strategy is proposed to provide bi-directional primary frequency regulation (BPFR) of an AC microgrid. In this strategy, in order to restrain the variation of frequency, the sliding mode surface is adaptively regulated to provide an adaptive power reserve. Thus, the PVs will have a power headroom to regulate the frequency both up and down through releasing the reserved power or increasing the reserves of the PV systems. Furthermore, the sliding mode surface is adaptively regulated only based on the locally measured frequency of the microgrid without the requirements of communication, detailed PV model, irradiance sensors as well as MPP estimators. Thus, the proposed control strategy shows the advantages of easy to implement and reduces the investment and maintenance costs of installing storage systems or irradiance sensors.

A dynamic general type-2 fuzzy system with optimized secondary membership for online frequency regulation

This study suggests a new control system for frequency regulation in AC microgrids. Unlike to the most studies, challenging conditions such as variation of wind speed, multiple load disturbance, unknown dynamics and variable solar radiation are taken to account. To cope with uncertainties, a novel dynamic general type-2 (GT2) fuzzy logic system (FLS) by an optimized secondary membership is suggested. The secondary membership and rule parameters of dynamic GT2-FLS are online tuned through the adaptive optimization rules. The optimization rules are determined such that the robustness and stability to be guaranteed. Also, a new compensator is presented to tackle with estimation error and perturbations. The simulations verify that schemed controller outperforms than conventional methods.

Whale Optimization Algorithm Based Tilt Integral Derivative Control for Frequency Regulation in AC Microgrid with and without SMES

Whale Optimization Algorithm Based Tilt Integral Derivative Control for Frequency Regulation in AC Microgrid with and without SMES

A novel fractional-order type-2 fuzzy control method for online frequency regulation in ac microgrid

In this paper, a novel adaptive fractional-order fuzzy control method is developed for frequency control in an ac microgrid (MG). A sequential general type-2 fuzzy system based on the radial basis neural network is presented for online modeling of the frequency response of the MG. Then, the parameters of the type-2 fuzzy controller based on the online estimated model are online tuned, such that the frequency deviation is minimized. The consequent parameters, i.e., centers of membership functions (MFs), the values of α-cuts, and the type-reduction parameters are optimized based on the proposed algorithm, which is inspired from the particle swarm optimization and artificial bee colony algorithm (PSO-ABC). The simulation results and comparison with other methods show that the proposed control scheme is effective, and results in a good and robust performance in the presence of variation of solar radiation, wind speed, load disturbance, and time-varying dynamics of the other units of MG. Moreover, the effectiveness of the proposed fuzzy system and the learning algorithm are examined by using white noise as the control input, and it is shown that the proposed identification scheme results in good performance even in the noisy environment.

Frequency Regulation in AC Microgrid with and without Electric Vehicle Using Multiverse-Optimized Fractional Order- PID controller

Frequency Regulation in AC Microgrid with and without Electric Vehicle Using Multiverse-Optimized Fractional Order- PID controller

Distributed SMC for Secondary Voltage and Frequency Regulation of AC Microgrid Adulterated by Communication Irregularities

Distributed SMC for Secondary Voltage and Frequency Regulation of AC Microgrid Adulterated by Communication Irregularities