Voltage application device and discharge device

A voltage application device comprising:

• a voltage application circuit that applies a voltage to a load including a discharge electrode that holds liquid, the voltage application circuit generating discharge in the discharge electrode;
• and
• a control circuit configured to control the voltage application circuit,
• wherein, during a drive period, the voltage application circuit periodically changes a magnitude of the voltage applied to the load at a drive frequency within a predetermined range including a resonance frequency of the liquid, the voltage application circuit mechanically vibrating the liquid,
• the load includes a counter electrode that is disposed to face the discharge electrode via a gap,
• the voltage is applied between the discharge electrode and the counter electrode, such that dielectric breakdown is generated between the discharge electrode and the counter electrode,
• the control circuit is configured to periodically perform
• (i) monitoring the output voltage of the voltage application circuit, and reducing energy input to the voltage application circuit, when the output voltage becomes greater than or equal to a maximum value and the dielectric breakdown is generated,
• (ii) monitoring an output current of the voltage application circuit after the dielectric breakdown occurs, and reducing energy input to the voltage application circuit, when the output current is greater than or equal to a threshold, such that the dielectric breakdown occurs intermittently in accordance with the drive frequency,
• during the drive period, the magnitude of the voltage changes within a range and the magnitude is greater than 0 V within the range,
• the liquid includes dew condensation water that is located on a surface of the discharge electrode, and
• the voltage application device further includes an adjuster that is configured to adjust a generation amount of the dew condensation water based on at least one of a temperature and a humidity.