Abstract: Abstract: With the mass access of rail transit and new energy in urban power grid， the active and reactive power transmission of urban power grid is serious， resulting in frequent voltage exceedance of urban power grid， and bringing major hidden dangers to the safe and stable operation of power grid. This paper presents an optimal allocation method of reactive power compensation equipment in urban power grid based on improved arithmetic optimization algorithm. Firstly， a comprehensive index of voltage stability is constructed by using reactive voltage sensitivity index and local voltage stability index to determine the position of reactive power compensation points. Secondly， the capacity optimization strategy of multi-objective reactive power compensation equipment is proposed， which takes into account the network active power loss， voltage deviation and equipment investment cost. Based on the traditional Arithmetic Optimization Algorithm （AOA）， improvements such as Kent chaos mapping， compound cycloidal method， Sparrow elite variation and Cauchy variation were introduced to improve the convergence speed and accuracy of the algorithm. Finally， an improved arithmetic optimization algorithm is used to solve the optimal configuration of reactive power compensation equipment. In this paper， IEEE30 nodes are used as simulation computing power for analysis， and the experimental results verify the effectiveness and rationality of the proposed method， which can improve the rationality of reactive power compensation equipment allocation in urban power grids.

Key words: Key words: urban power system, reactive power planning, comprehensive voltage stability index, analytic hierarchy process, improved arithmetic optimization algorithm