Distributed optimization decomposition for joint economic dispatch and frequency regulation

Abstract

Economic dispatch and frequency regulation are typically viewed as fundamentally different problems in power systems and, hence, are typically studied separately. In this paper, we frame and study a joint problem that cooptimizes both slow timescale economic dispatch resources and fast timescale frequency regulation resources. We show how the joint problem can be decomposed without loss of optimality into slow and fast timescale sub-problems that have appealing interpretations as the economic dispatch and frequency regulation problems respectively. We solve the fast timescale sub-problem using a distributed frequency control algorithm that preserves the stability of the network during transients. We solve the slow timescale sub-problem using an efficient market mechanism that coordinates with the fast timescale sub-problem. We investigate the performance of the decomposition on the IEEE 24-bus reliability test system.

Distributed optimal load frequency control considering nonsmooth cost functions

“…2. If x * is an equilibrium point of (7), (11), then (P l * , φ * ) is an optimal solution to (8) and (µ * , η + * , η − * ) is an optimal solution to its dual problem. 3. φ * i j = θ * i j for all (i, j) ∈ E. Moreover, the line limits are satisfied by x * , implying θ i j ≤ θ * i j ≤ θ i j on every tie line (i, j) ∈ E. 4.…”

“…Recently, the so-called reverse engineering methodology is proposed by combining frequency control with optimal operation problems in power systems [4,5,6,7,8]. Under this framework, distributed load frequency control is widely investigated [8,9,10,11,12,13,14].…”

Distributed Optimization Decomposition for Joint Economic Dispatch and Frequency Regulation

“…The latter can be interpreted as the expected changes in the marginal value of dispatch generation. Hence, if the latter is zero, then generation setpoints can be chosen optimally at the economic dispatch timescale without regard to the behavior of the system in the frequency regulation timescale [1].…”

Distributed load-side control: Coping with variation of renewable generations

“…Indeed, distributed optimal control has been investigated by combining controller design with optimal dispatch problems Jokić et al (2009); Zhang and Papachristodoulou (2015); Stegink et al (2017). It leads to a so-called reverse engineering methodology for designing optimal controllers, particularly in optimal frequency control of power systems Li et al (2016); Zhao et al (2014); Cai et al (2017). In this paper, we design a distributed load-side controller that is capable of adapting to power variation due to volatile renewable generations, such as wind farms and PV clusters.…”