The invention relates to a pole control system of a layered access system. With regard to a reactive power control function configured in a layered access ultrahigh-voltage DC power transmission system of a bipolar plate, a backup reactive power control master station is arranged in a measurement and control system, the backup reactive power control master station communicates with a measurement and control device through a local area network (LAN), a filter/capacitor running state of each AC network is acquired in real time, the pole control system communicates with the backup reactive power control master station according to a Profibus communication protocol, the backup reactive power control master station is used for reporting the filter/capacitor running state to the pole control system, and moreover, and a filter/capacitor switching sequence table is internally embedded into the backup reactive power control master station and is used for completing an overvoltage removal logic function of a filter/capacitor group. By the pole control system, the normal running of the system can be supported on the condition that a fault of a bipolar-layer control host exits, and the stable running of the DC power transmission system is ensured.