The increasing role of offshore wind power plants in the electricity generation mix in Turkey raises some critical grid operation issues. In this context, the grid code regulation concerning the penetration of large-scale offshore wind power plants into Turkey's power system has become a prominent factor in the development of a reliable grid operation. In this paper, a comprehensive benchmark for grid codes of the European countries that have large-scale offshore wind power plants and Turkey is performed by considering voltage regulation, frequency regulation, fault ride-through, and power quality features. The compatibility of the grid codes in terms of the minimum technical requirements is discussed to show the pros and cons. An elaborate assessment of the Turkish grid code reveals the technical properties that need to be improved. The rigorous state-of-the-art review indicates that active power control & frequency regulation, reactive power control & voltage regulation, and voltage ride-through capabilities should be clarified in detail for the Turkish grid code. With this background, various recommendations, key challenges, and future trends related to the improvement of technical requirements for the Turkish grid code for the integration of offshore wind power plants are highlighted to help researchers, plant owners, and system operators.
When an offshore wind power plant is connected to the grid, there is a risk of amplification of certain harmonics and appearance resonances at the point of connection due to the interaction between the grid network and the wind power plant network. Hence, the plant developer is obliged to maintain the harmonic distortion at the point of common coupling within the planning level limits using harmonic compensation, which is usually done by passive filters. In this paper a novel active harmonic compensation technique using voltage feedback from a non-local bus has been proposed and analyzed. Its effectiveness has been demonstrated through real time simulations on a test system model.
The share of renewables in the power system is increasing rapidly. Large offshore wind power plants (OWPPs) are developed at a high pace and conventional fossil fuel-based plants are decommissioned. If the OWPP gets islanded due to any contingency or in the event of a blackout, the whole OWPP will be shutdown. This paper proposes a STATCOM with a battery storage that is located at the point of common connection to an OWPP to enable OWPP energization from a fully discharged state to operate in islanded mode. The STATCOM functionality provides fast and dynamic reactive power management and the battery unit provides active power balancing capability to regulate the frequency in the island. The concept is demonstrated through time-domain simulations on an OWPP model in PSCAD. The results confirm the technical feasibility of the system.
The share of renewables in the power system is increasing rapidly. Large offshore wind power plants (OWPPs) are developed at a high pace and conventional fossil fuel-based plants are decommissioned. Consequently, there will be a risk of insufficient amount of power plants providing black start functionality for system restoration after a black out. This paper proposes a STATCOM with a battery energy storage that is located at the point of common connection to an OWPP that together can provide a reliable black start service to the power grid. The concept is demonstrated by using time domain simulations in PSCAD. The STATCOM functionality provides fast and dynamic reactive power management and the battery unit provides active power balancing capability to maintain the frequency within a tolerable range specified by the system operator. The simulation results fulfill the success criteria for the black start and confirm its feasibility for practical implementation.