Probabilistic Optimal Power Flow Method for HVAC/DC Systems Considering Wind Power Correlation

Due to the volatility and randomness of wind power, the wind power integration has an impact on the safe and stable operation of high voltage alternative/direct current systems (HVAC/DC), it is necessary to extend the probabilistic optimal power flow method to be applicable to HVAC/DC systems. This paper proposes a probabilistic optimal power flow method for a HVAC/DC system penetrated with correlated wind power. Firstly, the DC line and VSC are modelled as special components of an AC system, to which an AC optimal power flow model can be applied. Copula function is used as the joint probability distribution to describe the correlation between multiple wind farms. Based on the fitting Copula function, scenarios are generated to typify the wind power, and K-means clustering is utilized to obtain a small number of scenarios for the sake of relieving computation burden. Finally, an HVAC/DC test system with 14 buses is employed to verify the effectiveness of the proposed method.