Mohammad Esmaeil Nazari

This paper proposes a high-order sliding mode control strategy to improve the performance of power decoupling control for double-fed induction generators (DFIG). Initially, the mathematical model of DFIGs is analyzed based on the principle of voltage-oriented vector control. DFIGs efficient operation is vital for grid stability and power quality. However, these generators are susceptible to disturbances and uncertainties, which can affect their performance. To address this issue and poor dynamic performance of traditional control methods in achieving power decoupling and the nonlinearity of the wind turbine model, the proposed control method utilizes high-order sliding mode controller using power function approaching law. Simulation results demonstrate that the proposed control approach outperforms traditional PI controllers in terms of accuracy, robustness, and dynamic and static performance. A series of experiments, including no-load grid connection and power decoupling control, were successfully conducted on this platform. Analysis of the experimental waveforms for independent adjustment of active and reactive power shows that when either the active or reactive power is independently changed, the other power remains relatively constant. Therefore, the experimental results verified that the grid-connected power control strategy of the system can achieve dynamic decoupling control between active and reactive power.

The profit-based unit commitment is a maximisation problem, which consists of the revenue minus costs subject to related constraints. However, with increasing concerns for the global warming, environmental limitations must also be observed. The objective of this study is to develop a novel heuristic optimisation algorithm for solving profit-based unit commitment, considering selling reserve, satisfying demand, and environmental emissions. Without emission limitations, the results show profits between 0.02% and 17.60% for profit-based unit commitment, as compared with other algorithms reported in the literature. As far as emission limitations are considered, the profits of 1.65–118.71% and emission cost reduction of 2.16–7.79% are achieved, as compared with those found in literature.

Solar energy usage is thriving day by day. These solar panels are installed to absorb solar energy and produce electrical energy. As a result, the efficiency of solar panels depends on different environmental factors, namely, air temperature, dust (aerosols and accumulated dust), and solar incidence, and photovoltaic panel angles. The effects of real conditions factors on power and efficiency of photovoltaic panels are studied in this paper through testing the panel in real environmental tests. To study the mentioned parameters precisely, two panels with different angles are used. The case study is regarding a region of Tehran, Iran, in summer and winter seasons. The results show that panel efficiency during winter is higher than summer due to air temperature decrement. It is discovered that among air pollutants, Al and Fe have the most share in polluting the air that affect the photovoltaic efficiency. Moreover, measuring the accumulated dust on the panels shows more amount in winter in comparison with summer. The important point in studying the effect of tilt angle is that inconformity between solar incidence and photovoltaic panel angles would result in solar radiation absorption and eventually panel efficiency loss and also, photovoltaic panel installation angle would affect the amount of dust deposited on its surface.

Trigeneration is efficient to supply cooling, heat, and power demands. Also, hydro (pumped) storage with zero fuel costs can increase profit when price‐based scheduling problem is solved. The goal of this study is to investigate the effects of electric boiler, hydro storage, and heat storage tank on price‐based scheduling problem for hybrid trigeneration (trigeneration‐conventional‐gas boiler) system. A heuristic algorithm is applied to a power system where in validation case, total cost reduction of 0.63% to 0.91% is reached as compared with reported in literature. The results show that the utilization of electric boiler, hydro storage, and heat storage tank leads to profit improvement by 4.58%. Also, a critical sensitivity analysis is conducted and the results show the significant effects of several factors on scheduling results.

The integration of renewable wind and pumped storage with thermal power generation allows for dispatch of wind energy by generation companies (GENCOs) interested in participation in energy and ancillary services markets. However, to realize the maximum economic profit, optimal coordination and accounting for reduction in cost for environmental emission are essential. The goal of this study is to develop a simulation model for maximizing economic profit from coordination of renewable wind and pumped storage with thermal power generation for a GENCO with the participation in energy and ancillary services markets with considerations for environmental emission and uncertainty associated with wind power based on a newly developed heuristic optimization algorithm. The simulation results for validation of the heuristic optimization algorithm, as compared with those reported in the literature, show profit improvements of 8.58%–14.53% for uncoordinated and coordinated wind-pumped storage systems. It is determined that for a GENCO with 13 MW wind farm capacity and 1662 MW thermal units, for meeting an average demand of 1129 MW, the utilization of 120 MW pumped storage in a coordinated wind-pumped storage-thermal system results in reduction of environmental emission by 13.54%, which leads to an increase in profit by 2.10%, as compared with operation with no pumped storage unit.