This paper introduces the importance of the high-voltage shunt controllable reactor in power systems and the current study situation in China. The industrial prototype of 110 kV/30 Mvar shunt controllable reactor， its controller and protection devices are developed. The reactor's structure is described， and its work principle and characteristics are analyzed. What's more， this paper discusses the reactor's test process in the substation and investigates its parameters of characteristics. The presented shunt controllable reactor has been used at Tianjia 220 kV substation of Huaihua electrical grids in Hunan Province， which can stabilize the voltage of 110 kV bus at 115 kV.