Assessment of inertial and primary frequency control from wind power plants in the Mexican electric power grid

Abstract

Large-scale integration of converter-based renewable energy sources into power systems, such as wind generation, can lead to frequency stability issues due to the variable nature and lack of inertia of these technologies in combination with the gradual replacement of conventional generating units. However, wind turbine generators (WTGs) can be exploited to provide frequency support and keep system frequency stability requirements. A case study considering the Mexican Electric Power System is presented in this study to highlight both the impact of large-scale deployment of inverter-interfaced wind energy generation on system frequency response, and the participation of WTGs in inertial and primary frequency control (IPFC) as a mitigation approach. By incorporating synthetic inertia and droop control functions into the active power control loop of WTG converters, IPFC by wind generation is assessed for several wind shares, different active power modulation strategies based on the rate of change of frequency and frequency deviation, and several IPFC contribution levels under critical contingencies for generation outage. Simulation results show the combination of increasing share of wind energy generation in the study system and retirement of conventional generation has a clearly negative impact on system frequency dynamics. However, the incorporation of IPFC functions into wind power generators of the sample system, with appropriate control gain values, may contribute to effectively achieve an improved system performance in terms of grid frequency response under high wind power penetration scenarios.

Mitigation of Short-Term Fluctuations in Wind Power Output in a Balancing Area on the Road Toward 100% Renewable Energy

“…We propose five methods to mitigate STFs in the total wind power output in each BA, and compare the methods in terms of efficiency, which is indicated by the reduction in the absolute values of the STFs and the energy loss associated with application of the method. There are a number of studies on mitigation of the fluctuations in wind power output of single wind power plants (WPPs) and/or small systems consisting of several WPPs, and on the contribution of such mitigation to power systems [17], [18], [22], [23], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39]. In this study, we targeted the STFs in the total output of wind power in each BA and provide a framework for mitigating STFs.…”

Study on Quantitative Evaluation Index of Power System Frequency Response Capability

“…With the large-scale new energy resources and DC connected to a power grid, the proportion of traditional conventional synchronous units has gradually declined, and a large number of power electronic devices have been used in the power grid, resulting in the weakening of the inertia response and primary frequency modulation capability [5][6][7][8][9][10], so it is necessary to study and establish quantitative evaluation indexes of system-level frequency response capability to guarantee the stability of power grid frequency. References [11,12] analyze the virtual moment of inertia of wind power plants and propose the virtual inertia estimation method and active power control strategy of wind farms [11,12].…”