The invention provides a gas
station and a power device and a control method of the gas
station. The power device comprises a liquid suction and drainage tank and an air pressure adjusting mechanism. A liquid inlet of the liquid suction and drainage tank is connected with a first liquid outlet of a
liquid storage tank. A liquid outlet of the liquid suction and drainage tank is connected with a liquid charging
machine. An air inlet of the liquid suction and drainage tank is connected with a
high pressure air supply mechanism. An air outlet of the liquid suction and drainage tank is connected with a low pressure air exhaust mechanism. In the first state, the liquid outlet of the liquid suction and drainage tank is disconnected with the liquid charging
machine, the air inlet of the liquid suction and drainage tank is disconnected with the
high pressure air supply mechanism, the air outlet of the liquid suction and drainage tank is made communicated with the low pressure air exhaust mechanism, and the liquid inlet of the liquid suction and drainage tank is made communicated with the first liquid outlet of the
liquid storage tank. In the second state, the liquid inlet of the liquid suction and drainage tank is disconnected with the first liquid outlet of the
liquid storage tank, the air outlet of the liquid suction and drainage tank is disconnected with the low pressure air exhaust mechanism, the liquid outlet of the liquid suction and drainage tank is made communicated with the liquid charging
machine, and the air inlet of the liquid suction and drainage tank is made communicated with the
high pressure air supply mechanism. The power device can replace an immersed pump, the cost is reduced, and the maintenance cost is reduced.