As the reactive power /voltage control mismatch between the upper and the lower power networks may resultin danger and uneconomic power network operation,a model to evaluate the mismatch risk is proposed after analyzingthe concept of mismatch.In this model,a mismatch risk index is constructed by quantizing the high-sidevoltage,the low-side voltage,the available reactive power and the reactive power on power network boundaries.Moreover,a combinatorial analysis system of reactive power /voltage control is developed,which has such functionsas device account managenment,power flow analysis,mismatch risk evaluation and anti-mismatch strategy test.Case study results show that the proposed system is practical and feasible.