Solution on the Power Flow Violation Caused by Provincial Spot Market

China is improving power spot market operation. The provincial market will take the inter-provincial transaction results as the boundary for market clearing. However, when the inter-provincial AC tie line power is directly regarded as the injection power on the boundary nodes in the provincial market, the power flow model of the provincial market will deviate from the actual situation, and even the power flow violation occurs. This paper first proposes the clearing models of inter-provincial market and provincial market. Then the essential reason for the power flow violation is analyzed. Finally, the solution based on the provincial clearing model with phase angle difference constraint of boundary nodes is proposed. Case study shows that the solution can give the correct power flow calculation in provincial market and avoids the power flow violation.