DEVICE FOR PRESERVING FRESH, DEVICE FOR FRYING, GENERATOR OF SPATIAL POTENTIAL, DEVICE FOR WATER ACTIVATION, DEVICE FOR CULTIVATION, DEVICE FOR DRYING, DEVICE FOR MATURING, DEVICE FOR GROWING

摘要

A voltage application device (3) provided to this freshness keeping device is provided with: a feedback control circuit (32) which returns, to one terminal (35a) of a primary coil (35) of a transformer (31), one terminal (36a) of a secondary coil (36) of the transformer (31); an output control unit (33) which is connected to another terminal (36b) of the secondary coil (36); and a voltage adjustment unit (41) which switches the voltage value of an AC voltage (VL3) inputted from an AC power supply to a plurality of voltage values, and applies the voltage values to the primary coil (35) to adjust the voltage value of an AC voltage (VL1).