Analysis of interaction between ancillary service markets and energy market using power market simulator

In typical open power markets, generating units are allowed to bid their energy and capacity to energy and ancillary service markets at the same time. The system operator uses an optimization procedure to determine the accepted bids of units and clearing prices of different markets. Since the same generating unit can participate different markets simultaneously, different markets may impact one another. Study of how different markets interact with each other can provide insights to the market operation and behavior, which may be useful for market participants to make sound bidding decisions. However, this procedure can be complex and appropriate simulation tools would be helpful. In this paper, a power market simulator is utilized to study the interaction between ancillary service and energy markets. Ancillary service markets for regulation down reserve, regulation up reserve, spinning reserve, non-spinning reserve and replacement reserve are considered. Case studies using a model built on a power market located in the U.S. East Interconnect are reported.

I. Introduction

IN a competitive power market, there are energy market and different ancillary service markets. To ensure the electricity energy to be delivered reliably and the system to be operated securely, various ancillary services are needed [1]–[7]. There are different types of ancillary services such as voltage support, regulation, etc. The real power generating capacity related ancillary services, including regulation down reserve (RDR), regulation up reserve (RUR), spinning reserve (SR), non-spinning reserve (NSR) and replacement reserve(RR), are particularly important, and will be considered in this paper. Regulation is the load following capability under automatic generation control (AGC) [2]–[4]. SR is a type of operating reserve, which is a resource capacity synchronized to the system that is unloaded, is able to respond immediately to serve load, and is fully available within ten minutes. NSR differs SR in that NSR is not synchronized to the system. RR is a resource capacity nonsynchronized to the system, which is able to serve load normally within thirty or sixty minutes [2]–[4]. Reserves can be provided by generating units or interruptible load in some cases. When provided by generating units, the amount of reserve that can be supplied depends on the ramping rate, unit capacity and current dispatched output.