The three compressor trains on order are used for gas recovery from gas wells and for the transmission and compression of gas in the gas treatment and for stabilization.
The power generation system consists of three 40 megawatts steam turbine generation units. Mitsubishi didn't say how much the contract was worth.
The Japanese company received the orders from Technip of France, which along with Samsung Heavy Industries is carrying out the engineer, procurement and construction work for the Prelude FLNG hull.
The hull, which will be 488 metre long and 74m wide, forms the core of Shell's Prelude project, which will be deployed in the Browse basin over the Prelude gas field , about 200km offshore.
Prelude FLNG, which aims to become the first project to go on stream, will mostly use proven LNG technology adapted to a marine environment in terms of scale and operation.
Mitsubishi said that compared with gas turbines, which are generally used in conventional land-based LNG facilities, steam turbines permit continuous long-term operation as well as easier maintenance.
"The company believes its compressors' recognized advantages, combined with its track record in deliveries, led to its winning of the latest order," Mitsubishi said.
" Last May MCO concluded an Enterprise Framework Agreement with Shell relating to the supply of main compressors for use at LNG plants, and the company now looks to progressively build up a stable, long-term relationship with Shell as a strategic supplier," it added.