Energy-saving control device and method for reverse blowing fan of engine

The invention provides an energy-saving control device and method for an engine blowback fan. The engine blowback fan energy-saving control device comprises a blowback fan, a motor, a gear pump, a valve set, a pressure sensor, an energy accumulator, an oil can, a blowback fan built-in oil cylinder, a heat dissipation controller and a temperature sensor, the valve set comprises a one-way valve, a proportional overflow valve and a two-position two-way electromagnetic reversing valve, the motor is connected with the gear pump, the gear pump is connected with the oil can, and the pressure sensor is connected with the energy accumulator. The gear pump is connected with a one-way valve, the one-way valve is respectively connected with a proportional overflow valve and a two-position two-way electromagnetic directional valve, the proportional overflow valve is connected with an oil can, and the two-position two-way electromagnetic directional valve is connected with a built-in oil cylinder of the blowback fan; the p