Intra-day optimal power flow considering flexible workload scheduling of IDCs

Abstract

The online interactive workloads and offline batch computing services of Internet data centers (IDCs) have scheduling flexibility. Batch computing tasks with low latency sensitivity and priority can adjust the processing time and provide flexibility temporally. In contrast, interactive workloads with high latency sensitivity and priority can change the physical server for processing and provide flexibility spatially. Considering the change of power supply cost with time and space, the load flexibility of IDCs brought by Internet workload scheduling can be utilized to respond to the power system for more economical operation. To take full advantage of the flexibility of IDCs’ load demand, IDCs coordinated by an Internet service company (ISC) as a special controllable load with both temporal and spatial flexibility potential are considered. Instead of operating separately in normal optimal power flow (OPF) models, a two-stage interactive framework of the distribution system operator (DSO) and ISC is established. The operating state of the ISC is considered in OPF and is introduced as regularization terms into the objective function, thus fully exploiting its load flexibility. Some operation constraints are also added to guarantee the quality of service (QoS) of the ISC. The effectiveness of the model and the interactive framework are evaluated in a typical 33-bus medium-voltage distribution network. The results validate the further reduction of the power grid operation cost compared with the traditional OPF operation.

Keywords

• Optimal power flow
• Internet data center
• Load flexibility