Energy control for electrostatic precipitator

Claim 1

A method of controlling an electrostatic precipitator for reducing the dust content of exit gas from a plant which includes one or more precipitator sections, said method comprising charging each of said sections from a separate independent power supply for supplying a controllable high DC-voltage thereto, superimposing on said DC-voltage controllable high voltage pulses at a controllable repetition frequency, controlling the entire electrostatic precipitator towards minimum energy consumption at a certain set dedusting efficiency, by measuring the dust content in the exit gas from the entire precipitator and regulating the dedusting efficiency of the entire precipitator upwardly or downwardly depending on whether said measured dust content is above or below a preset value, the regulation being made through controlling the running parameters of one or more of the power supplies within set limits according to a control strategy selected among a plurality of predefined stored control strategies, each said control strategy comprising a sequence of instructions as to in what order, in which way and within which limits the DC-voltage, the pulse voltage and the pulse frequency of the respective power supplies of said precipitator sections are regulated, said dust content measurement determining if the instructions should be followed in forward or in reverse order, and how far the sequence of instructions should be followed.

Claim 2

A method of controlling an electrostatic precipitator for reducing the dust content of exit gas from a plant which includes one or more precipitator sections, said method comprising charging each of said sections from a separate independent power supply for supplying a controllable high DC-voltage thereto, superimposing on said DC-voltage controllable high voltage pulses at a controllable repetition frequency, controlling the entire electrostatic precipitator towards minimum energy consumption at a certain set dedusting efficiency, by measuring the dust content in the exit gas from the entire precipitator and regulating the dedusting efficiency of the entire precipitator upwardly or downwardly depending on whether said measured dust content is above or below a preset value, the regulation being made through controlling the running parameters of one or more of the power supplies within set limits according to a control strategy selected among a plurality of predefined stored control strategies, each said control strategy comprising a sequence of instructions as to in what order, in which way and within which limits the DC-voltage, the pulse voltage and the pulse frequency of the respective power supplies of said precipitator sections are regulated, said dust content measurement determining if the instructions should be followed in forward or in reverse order, and how far the sequence of instructions should be followed.

Claim 12

The method of any of claims 1 to 9, wherein said control strategy is made from a central unit and defined by a selected one of a plurality of predefined stored control strategies.