###### Abstract
The authors of [14] analyzed the transient voltage stability of the wind farm connection point, and created the transient voltage margin by formulating a reactive power compensation strategy. The authors of [15] optimized the configuration of wind and fire bundling capacity and DC drop point through a quantum particle swarm algorithm. The authors of [16,17] proposed a new type of reactive power compensation device or application scenario, but the scope of the application is limited. The authors of [18,19] proposed a combined reactive power compensation device, and optimized its topology and control strategy, but did not optimize the parameters. The existing voltage control methods have shortcomings in terms of adjustment range and response speed. The authors of [20-24] proposed a corresponding dynamic coordinated control strategy to improve the support capability of the voltage. However, the selection of dynamic reactive power planning address based on trajectory sensitivity has been introduced in detail, and the corresponding characteristics and effects of reactive power compensation of two commonly used dynamic reactive power compensation devices, SVC and STATCOM, have been fully compared and analyzed. The main contributions of this paper are as follows:  
* Using the advantages of fast response and strong economy of the combined reactive power compensation device, a control strategy for the reactive power compensation system based on the wind farm is formulated. This strategy not only avoids the frequent switching of capacitor banks but also guarantees the linear demand of the system for reactive power. * The active power margin and modal numerical analysis of the wind power gathering area in the Hami area show that the Mahuanggou east wind farm, located in the Santanghu wind area, is the weak node of voltage in this area, so this area is the best place to install reactive power compensation devices. * The improved particle swarm algorithm is used to optimize the capacity of the optimal reactive power compensation device, which ensures the best performance of the compensation device. * Using PSCAD simulation software to model the power grid in the Hami area, six different reactive power compensation device configuration programs are set up for static voltage stability simulation verification, as well as three different reactive power compensation device combination programs for transient voltage stability simulation verification. In summary, in order to solve the problem of weak voltage support in wind power gathering areas, considering the continuity and smoothness of regulation in reactive power compensation, and taking into account the economy of cost, this paper proposes a new combined reactive power compensation device composed of SVG and a capacitor bank. Taking the Tianzhong DC near-area power grid as an example, we analyzed and derived the voltage weakness area of the grid, used the improved particle swarm algorithm to find the optimal capacity of the compensation device, and finally verified the effectiveness of the method by setting up four configuration programs, which have guiding significance for the power grid in this area.