Automatic control method for electrochemistry heavy metal sewage treatment system

The invention discloses an automatic control method for an electrochemistry heavy metal sewage treatment system. The automatic control method comprises the following implementation steps: (1) obtaining the detection index value of treated heavy metal sewage; (2) inputting the detection index value in a preset relational mapping mathematical model to obtain an output current value enabling the running power of a rectifier of the electrochemistry heavy metal sewage treatment system to be the minimum; (3) controlling the rectifier of the electrochemistry heavy metal sewage treatment system to output the output current value enabling the running power of the rectifier to be the minimum so as to enable the electrochemistry heavy metal sewage treatment system to run with the minimum power. According to the invention, the electrochemistry current is automatically tracked and adjusted along with the change of the detection index value to enable the electrochemistry current to be always at the critical value, so that the electrochemistry always operates at the minimum running power on the condition that the index reaches the standard, electric energy is saved, and the operating time of a polar plate is prolonged.