Dynamic Simulation of Compressor Station Operation Including Centrifugal Compressor and Gas Turbine

Abstract

Dynamic simulation of the operation of a compressor station requires mathematical modeling of the dynamic behavior of the compressor unit and various piping elements. Such models consist of large systems of nonlinear partial differential equations describing the pipe flow together with nonlinear algebraic equations describing the quasi-steady flow through various valves, constrictions, and compressors. In addition, the models also include mathematical descriptions of the control system, which consists of mixed algebraic and ordinary differential (mad) equations with some inequalities representing controllers’ limits. In this paper a numerical technique for the solution of the gas dynamics equations is described, based on the transfer matrix formulation relating the state vector time difference at one side of an element to that on the other side. This approach facilitates incorporation of all element transfer matrices into an overall transfer matrix according to the system geometric connectivity. The paper also presents simulation results and comparison with actual field measurements of three case histories: (1) simulation of a compressor surge protection control process; (2) unit startup; and (3) slow transient of a compressor station responding to changes in the discharge pressure set point. Good agreement between simulation results and field measurements is demonstrated.

Analysis of biogas compression system dynamics

“…Different models [10,[39][40][41][42][43][44] have been presented in literature dealing with modeling compression systems and set up of surge avoidance strategies. In Ref.…”

“…In Ref. [39], a model was developed and applied to three test cases: a compressor surge protection control, a compressor start-up for a single unit compressor station and a compressor station set point change for a compressor station composed of two compressors in series. In Ref.…”

Development of Compression System Dynamic Simulation Code for Testing and Designing of Anti-Surge Control System

“…The dynamic behavior of the system is described by the gas properties values in the nodes connecting two modules. The mathematical model used in this paper was developed by researchers in Ref [12,13], where the continuity and momentum conservation equations were utilized in their investigation. A typical schematic of a real industrial compression system is shown in Fig.…”

“…(3) Equation (3) represents the spool dynamics, is the driver unit moment of inertia, is the supplied driver moment which is an input to the system, and is the torque on the shaft from the compressor. The final expression of governing equations for implementing in the FORTRAN code can be acquired by some assumption and simplification, as stated below [12]:…”

“…Although, Helvoirt and Jager stated that the Greitzer model alone is not adequate on the dynamic modeling of a much more complex system like large industrial compression system in the process plants and pipeline compressor satiations [10]. The systematic model presented by Botros et al was one of the most comprehensive works that aimed at analyzing such complex compression system components dynamic interactions, particularly during ESD 1 [11,12]. In this approach, the Greitzer and Moore model [13] has been extended to centrifugal compressors.…”