Dynamic leader based collective intelligence for maximum power point tracking of PV systems affected by partial shading condition

Comprehensive overview of maximum power point tracking algorithms of PV systems under partial shading condition

A novel Competence Square based PV array reconfiguration technique for solar PV maximum power extraction

A review on online state of charge and state of health estimation for lithium-ion batteries in electric vehicles

A state-of-the-art differential evolution algorithm for parameter estimation of solar photovoltaic models

Comprehensive overview of meta-heuristic algorithm applications on PV cell parameter identification

Perturbation observer based fractional-order PID control of photovoltaics inverters for solar energy harvesting via Yin-Yang-Pair optimization

Parameter identification of PV cell via adaptive compass search algorithm

This paper proposes a perturbation estimation-based nonlinear adaptive control (NAC) for a voltage-source converter-based high voltage direct current (VSC-HVDC) system which is applied to interconnect offshore large-scale wind farms to the onshore main grid in order to enhance the fault ride-through (FRT) capability of Type-4 wind energy conversion systems (WECS). The VSC-HVDC power transmission system is regraded as a favourable solution for interconnecting offshore wind farms. To improve the FRT capability of offshore power plants, a de-loading strategy is investigated with novel advanced control of the VSC-HVDC systems. The proposed NAC does not require an accurate and precise model and full state measurements since the combinatorial effects of nonlinearities, system parameter uncertainties, and external disturbances are aggregated into a perturbation term, which are estimated by a high-gain perturbation observer (HGPO) and fully compensated for. As the proposed NAC is adaptive to system model uncertainties (e.g., mismatched output impedance of the converters and the line impedance of transmission line), time-varying disturbance (e.g., AC grid voltage sags and line to ground faults), and unknown time-varying nonlinearities of the power-electronic system (e.g., unmodelled dynamics existed in valve and VSC phase-locked loop system), a significant robustness can be provided by the de-loading strategy to enhance the FRT capability. Simulation results illustrated that the proposed strategy can provide improved dynamic performance in the case of operation with a variety of reduced voltage levels and improved robustness against model uncertainties and mismatched system parameters comparing with conventional vector control.

/pdf/fault-ride-through-capability-enhancement-of-type-4-wecs-in-1nlrmicucr.pdf

Fault Ride-Through Capability Enhancement of Type-4 WECS in Offshore Wind Farm via Nonlinear Adaptive Control of VSC-HVDC

This study proposes a novel fractional-order feedback linearization sliding-mode controller (FoFLSMC) for photovoltaic (PV) inverters connected with grid, which aims at rapidly and effectively controlling the PV inverter. Firstly, the dynamic characteristics of rotational synchronous dq-axis PV inverter are developed. Then, the DC voltage and q-axis current are chosen as output to realize active power and reactive power regulation. The original PV inverter is linearized, upon which FoFLSMC is designed to globally remove the nonlinearities and significantly enhance the robustness. In particular, a fractional-order traditional sliding-mode control (SMC) based on integer order, PDα sliding surface is employed, compared with this method can significantly enhance the tracking performance. Meanwhile, the discontinuous function sgn() can be replaced by the continuous sat(.) function, such that the chattering effect can be largely reduced.

Fang Zeng

Papers

Comprehensive overview of meta-heuristic algorithm applications on PV cell parameter identification

Perturbation observer based fractional-order PID control of photovoltaics inverters for solar energy harvesting via Yin-Yang-Pair optimization

Parameter identification of PV cell via adaptive compass search algorithm

Fault Ride-Through Capability Enhancement of Type-4 WECS in Offshore Wind Farm via Nonlinear Adaptive Control of VSC-HVDC

Fractional-order Feedback Linearization Sliding-mode Control Design for Grid-connected PV Inverters