Robust trajectory-constrained frequency control for microgrids considering model linearization error

Zhang, Yichen (ORCID:0000000269250775); Chen, Chen (ORCID:0000000283645749); Hong, Tianqi (ORCID:0000000313076808); Cui, Bai; Xu, Zhe (ORCID:0000000204400912); Chen, Bo (ORCID:0000000341450676); Qiu, Feng

doi:10.1016/j.apenergy.2022.120559

DOE OSTI · 1922629

Robust trajectory-constrained frequency control for microgrids considering model linearization error

Zhang, Yichen (ORCID:0000000269250775)·Chen, Chen (ORCID:0000000283645749)·Hong, Tianqi (ORCID:0000000313076808)·Cui, Bai·Xu, Zhe (ORCID:0000000204400912)·Chen, Bo (ORCID:0000000341450676)·Qiu, Feng

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Abstract

Grid supportive modes integrated within inverter-based resources can improve the frequency response of renewable-rich microgrids. The synthesis of grid supportive modes to guarantee frequency trajectory constraints under a predefined disturbance set is challenging but essential. To tackle this challenge, a numerical optimal control (NOC)-based control synthesis methodology is proposed. Without loss of generality, a wind-diesel fed microgrid is studied, where we aim to design grid supportive functions in the wind turbine. In the control design, linearized models are used, and the linearization-induced errors are quantitatively analyzed by reachability and interval arithmetics and represented in the form of interval uncertainties. Then, the NOC problem can be formulated into a robust mixed-integer linear program. The control structure is strategically configured into two levels to realize online deployment. The proposed control is verified on the modified 33-node microgrid with a full-order three-phase nonlinear model in Simulink. In conclusion, the simulation results show the effectiveness of the proposed control paradigm and the necessity of considering linearization-induced uncertainty.

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24 POWER TRANSMISSION AND DISTRIBUTION 42 ENGINEERING Microgrids frequency response interval analysis mixed-integer linear programming numerical optimal control reachability uncertainty quantification wind turbine generator

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Zhang, Yichen (ORCID:0000000269250775), Chen, Chen (ORCID:0000000283645749), Hong, Tianqi (ORCID:0000000313076808), Cui, Bai, Xu, Zhe (ORCID:0000000204400912), Chen, Bo (ORCID:0000000341450676), Qiu, Feng. 2022-12-30. Robust trajectory-constrained frequency control for microgrids considering model linearization error. https://doi.org/10.1016/j.apenergy.2022.120559

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