Guoji Sun

Optimization-Based Generation Asset Allocation for Forward and Spot Markets

One of the most important daily decisions that a Genco has to make is to allocate generation assets between the forward and spot markets. That is, how much capacity should be contracted in the forward market and how much should be kept to bid in spot market? This paper focuses on generation asset allocation between monthly forward contracts, such as bilateral contracts, futures contracts, options contracts, and daily spot markets, considering operating costs and constraints of generating units, as well as spot price risk. The problem is to find the optimal hedging position based on the known forward price and the forecasted hourly spot prices and is formulated based on the model of PJM market. The double dynamic programming method is applied to solve this optimal asset allocation problem with all the short-term operating constraints of the generating unit satisfied. Three types of forward contracts that are commonly used in practice are considered and their impact on generation asset allocation are analyzed and compared. The analytic relationship between the optimal contract quantity of a particular type and spot generation is established. Based on this relationship, the applicability and characteristics of a particular type of contract are discussed. Furthermore, with the solution to the generation asset allocation problem as a basis, the pricing strategy in the forward market is analyzed. A Nash game model is established and an iterative process is developed to determine the equilibrium pricing of futures contracts. Numerical testing shows that the method for the generation asset allocation is effective. Various factors influencing the decision of generation asset allocation and the relationship between futures contract price and spot price are tested and analyzed.

Social welfare maximization auction for electricity markets with elastic demand

One of the most important issues in electric power market design is to create an appropriate auction mechanism. And one of the most common failures of power market is lack of demand side response to high market price. This paper discusses the bid cost minimization auction mechanism and social welfare maximization auction mechanism in pool market with demand elasticity. A social welfare maximization auction model with elastic demand is presented in this paper. The traditional unit commitment and economic dispatch approach is adapted to solve this power market centralized control problem in the spot pricing model by replacing the objective function with maximum social welfare. Numerical testing results show that this method is efficient.

A new algorithm of data distribution management for distributed interactive simulation

In the distributed interactive simulation based on HLA/RTI, a key problem is how to effectively establish information exchange and delivery mechanism between federates to meet the requirements of the scalability of system. This paper discusses the basic data filtering mechanisms of RTI1.3. Then a new data distribution strategy is proposed: firstly it calculates update and subscription regions matching by grid-based method, then it dynamically allocates multicast groups based on current cells in which there are update and subscription regions overlapped. In order to determine the optimal cell size, a computation model is established. The simulation results show that the algorithm proposed could effectively reduce complexity of region matching and make use of multicast groups.

Research on time warp mechanism in HLA

HLA (high level architecture) components initiative intends to have a high level of interoperability among simulations and allows maximum components reusability. However, to time warped algorithm, the RTI (runtime infrastructure) servers are difficult to use. This paper outlines two methods in HLA to help optimist federates perform rollback procedures when needed, the common way and the computational reflection way, to implement the mechanism and then to compare them. In the common way, the optimistic federate programming task is heavy, while in using the last way it increases flexibility by adding meta-object, and decreasing programming complexity. The conclusion is, we can add the computational reflection techniques to the HLA time management, and strengthen HLA in optimistic synchronization schemes in parallel and distributed simulation.

A game theoretic model for equilibrium pricing of futures electricity contracts

Due to the unique characteristics of electricity markets, the traditional methods to futures contracts pricing, which have been widely used to common commodity, can not be applied directly. This paper presents a Cournot game model for equilibrium pricing of futures electricity contracts. In the game, each Genco optimizes a generation asset allocation problem between monthly futures contracts and the daily spot market, with consideration of market power in futures market, price risk in spot market and operating costs and constraints of generating units. An iterative method is applied to obtain the Cournot-Nash equilibrium of the futures contract prices. Finally, the possible factors influencing the futures price equilibriums are discussed with case studies.

Optimal generation portfolio management for futures and spot market

One of the most important decisions that a Genco has to make is to determine generation portfolio management of the spot and futures market. That is, how much capacity should be put into the futures market and how much should be kept to bid in the spot market. This paper focuses on the generation portfolio management between monthly futures market and daily spot market. It deals with the problems of optimal hedging position based on the current forward price and the forecasted hourly spot prices. The problem is formulated based on the model of PJM market and the double dynamic programming method developed in our previous work is applied to solve this optimal portfolio management problem with all the short term operating constraints satisfied. Numerical testing results show that this method is efficient and optimal generation portfolio is obtained based on current futures price and forecasted spot market prices

Zero power control of 0.5 KWh class flywheel system using magnetic bearing with gyroscopic effect

This paper proposes a new method how to construct the reduced-order model of rotor system with gyroscopic effect used for control system design of closed loop system. In order to demonstrate the validity of this method, the controlled model and zero power control of a 0.5 KWh class flywheel system using magnetic bearing with gyroscopic effect are given in this paper. The proposed method is verified by experiment in this paper.

The H/sub /spl infin// control of 10MWh class energy storage flywheel system using superconducting magnetic bearing without gyroscopic effect

The paper is concerned with a feasibility study to realize a 10MWh class energy flywheel system based on computer simulation. First, we propose a quantitative size and specification of the 10MWh class energy storage flywheel system. Then conceptual design, vibration analysis, control model, and stability control are discussed.

Balanced Auction Mechanism for Electric Power Markets

One of the most important issues in electric power market design is to create an appropriate auction mechanism. A well-designed auction mechanism should find a reasonable balance between market efficiency and equity. This paper discusses the relationship between supplier bid cost minimization and market efficiency and that between consumer payment minimization and market equity. A balanced auction mechanism based on multi-objective function is presented to have a balanced consideration of efficiency and equity. A framework incorporating supplier bid cost unit commitment and consumer payment dispatch is applied to address this issue and a new method based on multilevel ordering is developed to solve this problem. Numerical testing results show that this method is efficient and the new model can appropriately balance the market efficiency and the equity.

Research on a new data distribution strategy for DDM

In the distributed interactive simulation based on HLA/RTI, a key problem is how to establish information exchange and delivery mechanism among federates effectively to meet the requirements of system scalability. This paper discusses the basic data filtering mechanism of RTI1.3, then a new data distribution strategy is proposed: this algorithm computes region matching using grid-based method firstly, then it allocates multicast groups based on publisher dynamically. The simulation result show that the strategy proposed could reduce complexity of region matching and make use of multicast groups effectively.