Abstract: Abstract:The composition of the heat supply network system of 300MW cogeneration unit was introduced. The problems happened in operation of water circulating pump in heat supply network were analyzed. A variable frequency energysaving reformation scheme for the water circulating pump in heat supply network was put forward. The total water supply flow of the heat supply network was regulated by the regulating valve installed in outlet of the water circulating pump originally; and in the reformation scheme the total water flow will be regulated by the reformed water circulating pump directly. After the scheme was implemented, the operation and maintenance cost of the unit was decreased; the heat supply safety factor of the heat supply network was increased; the economic benefit and the social effect of the enterprise were enhanced.

Key words: Keywords:water circulating pump in heat supply network, variable frequency reformation, decreasing of house service consumption rate, safety of heat supply