초록 ▼

A method and apparatus are disclosed for controlling a multicompressor station so that the overall work requirement of the station is minimized while maintaining the compressors in a non-surge conditions. The apparatus includes interconnected control loops for controlling the turbine speed of variab

A method and apparatus are disclosed for controlling a multicompressor station so that the overall work requirement of the station is minimized while maintaining the compressors in a non-surge conditions. The apparatus includes interconnected control loops for controlling the turbine speed of variable speed compressors or the throttling valves of constant speed compressors that determine a set of criterion for computing the value and sign of the first derivative of work performed by the station. The speed of each compressor is then set to reduce overall system work while maintaining discharge pressure of the station and maintaining the compressors in a non-surge operating format. The method includes the steps of computing the criterion, computing the value and sign of the first derivative of the work function and adjusting the compressor speed to minimize station work while maintaining the compressors in a non-surge condition.

대표청구항 ▼

[ I claim:] [1.] A control system for optimizing the overall work performed by a compressor station having multiple compressors with associated governors and prime movers where the governors and prime movers vary the performance of each compressor, said system comprising:a. surge means for maintaini

[ I claim:] [1.] A control system for optimizing the overall work performed by a compressor station having multiple compressors with associated governors and prime movers where the governors and prime movers vary the performance of each compressor, said system comprising:a. surge means for maintaining each of the compressor in a non-surge condition;b. pressure means for maintaining the station output at a desired pressure or suction;c. a work means for controlling performance of each compressor in the station to minimize an overall work function for the station; andd. control means which computes, on a periodic basis, a DEV value for each of the compressors, where each of DEV value represents a deviation from a compressor surge control line for the compressor, an INCR value for each of the compressors, where each INCR value represents an increment of the system work function based on a step upset of a mass flow balance between the compressors, and a dW value or .DELTA.W value which represents a station differential work value derived from the INCR values from at least two periods or scans.