In the operation of pipeline networks, compressors play a crucial role in ensuring the
network’s functionality for various scenarios. In this contribution we address the
important question of finding the optimal location of the compressors. This problem
is of a novel structure, since it is related to the gas dynamics that governs the
network flow. That results in nonconvex mixed integer stochastic optimization
problems with probabilistic constraints.
Using a steady state model for the gas flow in pipeline networks including
compressor control and uncertain loads given by certain probability distributions, we
consider the problem of finding the optimal location for the control on the network
such that the control cost is minimal and the gas pressure stays within given
bounds.
In the deterministic setting, we present explicit bounds for the pipe length and
the inlet pressure such that a unique optimal compressor location with minimal
control cost exists. In the probabilistic setting, we give an existence result for the
optimal compressor location and discuss the uniqueness of the solution depending on
the probability distribution. For Gaussian distributed loads a uniqueness result for
the optimal compressor location is presented.
We further present the problem of finding optimal compressor locations on
networks including the number of compressor stations as a variable. Results for the
existence of optimal locations on a graph in both the deterministic and the
probabilistic setting are presented, and the uniqueness of the solutions is discussed
depending on probability distributions and graph topology. The paper concludes with
an illustrative example on a diamond graph demonstrating that the minimal number
of compressor stations is not necessarily equal to the optimal number of compressor
stations.
Keywords
gas network, compressor control, compressor location, Weber
problem, optimal location, uncertain boundary data,
nonconvex mixed integer stochastic problem