A fair method for centralized optimization of multi-TSO power systems

Abstract

Abstract-This paper addresses the problem of centralized optimization of an interconnected power system partitioned into several regions controlled by different transmission system operators (TSOs). It is assumed that those utilities have agreed to transferring some of their competencies to a centralized control center, which is in charge of setting the control variables in the entire system to satisfy every utility's individual objective. This paper proposes an objective method for centralized optimization of such multi-TSO power systems, which relies on the assumption that each TSO has a real-valued optimization function focusing on its control area only. This method is illustrated on the IEEE 118 bus system partitioned into three TSOs. It is applied to the optimal reactive power dispatch problem, where the control variables are the voltage settings for generators and compensators. After showing that the method has some properties of fairness, namely freedom from envy, efficiency, accountability, and altruism, we emphasize its robustness with respect to certain biased behavior of the different TSOs.

On the inter-area optimal voltage and reactive power control

“…Observations show that reactive power flows are rarely negligible at the interconnection links [11]. The coordinated voltage and reactive power control in MAPS has been investigated in the literatures [10,[12][13][14][15][16][17]. A new layer of hierarchical control to coordinate long-term control actions over several control areas in normal operating conditions is proposed in [11].…”

“…Reactive power capacity limit of each generator are specified by Q . In (13) and (14) V i is the generator terminal voltage, P i is the generator active power output, I fi is the maximum field current, I ai is the maximum armature current, and X si is the synchronous reactance.…”

Coordination of voltage control in a power system operated by multiple transmission utilities

“…Additionally, the scheme might also not be robust with respect to the biased behavior of one or several parties [8].…”

“…On one hand, centralized operation has been proposed to coordinate reactive power dispatch [8]. It usually consists of a centralized control center gathering information from different utilities, making decisions for the entire system, and advising system operators.…”

“…This paper provides an evaluation of the centralized control scheme proposed in [8] and the decentralized control scheme proposed in [14] on a 4141 bus power system representing the western part of the UCTE system, which is operated by 7 different TSOs. Those strategies are also compared with the current practice in the UCTE system, modeled as a particular instance of the decentralized coordination scheme.…”