HEAT PUMP TYPE WATER HEATING UNIT BASED ON PEAK AND OFF-PEAK POWER CONSUMPTION, CONTROL METHOD THEREFOR AND CONTROL SYSTEM THEREOF

摘要

A heat pump type water heating unit based on peak and off-peak power consumption, a control method therefor and a control system thereof. The control method comprises the following steps: an off-peak electricity signal determining step: determining whether an off-peak electricity signal is inputted, and if yes, performing the start controlling step for a heat pump and a secondary thermoelectric device, if not, controlling the operation of the heat pump type water heating unit in a normal way; and the start controlling step for the heat pump and the secondary thermoelectric device: controlling the heat pump and the secondary thermoelectric device to start, according to value comparison between a current water tank temperature T5 and a water tank setting temperature Ts and between the current water tank temperature T5 and a secondary thermoelectric device starting temperature T5start. The heat pump and the secondary thermoelectric device are controlled to start by determining whether an off-peak electricity signal is inputted, avoiding the secondary thermoelectric device starting too early; the heat pump and the secondary thermoelectric device in particular are controlled to start by determining the value comparison between T5 and Ts and between T5 and T5start, ensuring the accurate start time of the secondary thermoelectric device, avoiding the secondary thermoelectric device starting too late.