Circulating tunnel drying equipment and control method thereof

The invention discloses circulating tunnel drying equipment and a control method thereof. The equipment comprises an annular tunnel, a transporting mechanism and a dehumidifying mechanism, wherein a microwave heating area, an infrared heating area and a loading and unloading area are arranged in the annular tunnel; a microwave generator is arranged in the microwave heating area; an infrared heateris installed in the infrared heating area; an openable door body is arranged in the loading and unloading area; the transporting mechanism includes an annular guide rail, a motor vehicle and a trailer; the annular guide rail is arranged in the annular tunnel; the trailer is connected to the motor vehicle and moves with the motor vehicle along the annular guide rail in the annular tunnel; the dehumidifying mechanism includes an air passage, a draught fan and a heat pump component; the heat pump component comprises a compressor, a condenser, a throttling device and an evaporator connected together; the air passage is p