What is a combined box-type substation?

The combined box-type substation is to put the transformer body, high-voltage load switch, fuse and high and low voltage connections in a common enclosed oil tank. The transformer oil is used as the insulating medium between the phases and the ground of the live part. This kind of power distribution equipment is compact, small in size, economical and practical.

Combined box-type substations generally use the following two combinations of energy-saving combined transformers. Transformer core materials generally use high-quality grain-oriented cold-rolled silicon steel sheets or high-efficiency energy-saving amorphous alloy sheets.

ZG (combined common tank) type common tank combined oil-immersed transformer. The transformer puts high-voltage load switches, fuses and other protective and control appliances, and transformer cores in the same oil tank.

ZF (combined sub-tank) type sub-tank combined oil-immersed transformer. The transformer oil tank is equipped with two independent closed units, one of which is equipped with high-voltage load switches, fuses and other control and protection appliances, and the other unit is equipped with the transformer core.

The transformer body and the combined box-type substation box form a whole, the heat dissipation surface of the transformer is exposed outside the substation box, and the plug-in fully insulated cable head is connected to the power supply. The box body of the combined box-type substation is equipped with high-voltage and low-voltage compartments. The front of the box has a high and low pressure operation interval. In the operation interval, there are high and low voltage terminals, load switch operating handles, no-load pressure regulating switch, plug-in fuse, pressure release valve, oil temperature gauge, oil level gauge, etc. The high and low pressure compartments are equipped with interlocking devices, and the high pressure compartments cannot be opened when the low pressure compartments are not opened. The plug-in fuse (primary protection) is connected in series with the backup protection fuse to form a secondary protection.

Install low-voltage control appliances (low-voltage main switch and branch outlet switches, etc.) and manual or automatic reactive power compensation devices and other electrical equipment in the low-voltage interval according to the required wiring plan.

The combined box-type substation can be equipped with a metering device as required, and can be equipped with high and low voltage arresters, lack of phase controllers, intelligent undervoltage controllers, condensation controllers, live monitors, fault indicators, telemetry and remote communication integrated power distribution measurement Instrument and other protection and monitors.