2019/08/21 by Andreas Kasis, Kasis, Andreas, Nima Monshizadeh +3
Engineering · #FOS: Mathematics #Frequency Control in Power Systems #Microgrid Control and Optimization #Optimization and Control (math.OC)
paper · pdf · doi:10.48550/arxiv.1908.08077
openalex publication_date 2019/08/21 · openalex created_date 2022/07/28 · openalex updated_date 2026/07/28
Load side participation can provide valuable support to the power network in\ncase of urgencies. On many occasions, loads are naturally represented by on and\noff states. However, the use of on-off loads for frequency control can lead to\nchattering and undesirable limit cycle behavior, which are issues that need to\nbe resolved for such loads to be used for network support. This paper considers\nthe problem of primary frequency regulation with ancillary service from on-off\nloads in power networks and establishes conditions that lead to convergence\nguarantees and an appropriate power allocation within the network. In\nparticular, in order to assist existing frequency control mechanisms, we\nconsider loads that switch when prescribed frequency thresholds are exceeded.\nSuch control policies are prone to chattering, which limits their practicality.\nTo resolve this issue, we consider loads that follow a decentralized hysteretic\non-off policy, and show that chattering is not observed within such a setting.\nHysteretic loads may exhibit, however, limit cycle behavior, which is\nundesirable. To address this, we propose an adapted hysteretic control scheme\nfor which we provide convergence guarantees. Furthermore, we consider a\nmixed-integer optimization problem for power allocation and propose a suitable\ndesign of the control policy such that the cost incurred at equilibrium is\nwithin \ε from the optimal cost, providing a non conservative value for\n\ε. The practicality of our analytic results is demonstrated with\nnumerical simulations on the Northeast Power Coordinating Council (NPCC)\n140-bus system.\n