Sharif Digital Repository

Economic aspects of power systems in their new structures, have been the subject of most of new publications in the area of electrical engineering after the era of restructuring. Nowadays, the power generation business is totally market driven in most of countries all around the world and the system operators are responsible for maintaining a high level of system security as well as the economic operation of the power systems. The development of wind power generation has rapidly progressed over the last decade. With the advancement in wind turbine technology, wind energy has become competitive with other fuel-based resources. The fluctuation of wind, however, makes it difficult to optimize the... 

In most countries Frequency control services as one of the Ancillary services are presented in market scheme. Frequency control are used in different levels to balance generation and demand. Each reserve levels is implemented with specific characteristics and rules. Clearance of energy and one control reserve has some drawbacks so in this thesis we try to clear energy and different reserve levels simultaneously. Each reserve level is determined with special criteria. This criterion in primary reserve is frequency deviation restriction and unit commitment risk in territory reserve that is determined by system operator. In this thesis these two criteria are formulated in linear form and... 

In restructured power system, the Independent System Operator (ISO) implements Security Constraint Unit Commitment (SCUC) for clearing of day-ahead market. In this project, SCUC is also uses for simultaneous clearing of energy and reserve market. Spinning reserve and of generating units and Interruptible Loads (IL) are considered as system operating reserves in the proposed model. Some of IL usage restrictions such as maximum load curtailed, maximum curtailment hour in a day, maximum length of each curtailment and etc is also considered. One of these constraints is interruption time (the time between ISO’s request and IL’s Answer) which is very difficult to formulate. Expected Energy Not... 

Wind power is site dependent and is by nature partially dispatchable. Furthermore, good wind sites are far from grid. Due to these problems, and along with the existing limitations in the transmission networks, a comprehensive analysis over an extended time is needed to properly explore all potential wind sites for wind capacity allocation. This problem is computationally expensive and decomposition methods are required to break down this problem. Here Benders decomposition approach is used, which is a popular technique for solving large-scale problems, to decompose the original problem into a master and a subproblem. The master problem is a linear problem, which allocates wind capacity to... 

Considerable developments in demand-side real-time telemetry systems allow ISOs to use demand-side provided reserves in ancillary service markets. Presently, many ISOs designed programs to utilize the reserve provided by demand response resources in their market, and deploy them in emergency conditions. These programs are called ancillary service demand response (ASDR) programs. This thesis presents a stochastic programming model to schedule reserve provided by demand response resources in load buses of system. The demand-side reserve resources are modeled by demand response providers (DRP) which have the responsibility of aggregating and managing responses of customers. The reserve provided... 

The everyday increasing electricity consumption of household and industrial sectors across the world, and also the limited generation capacity and fuel supplies has led electricity companies, whether in private or government sectors, to focus deliberately on power generation planning, its costs, risks and constraints Because of many reasons including high efficiency, low cost of capital investment, expeditious permitting, and operation flexibility of gas-fired generating units, electricity companies prefer them to old ones like coal-fired or oil-fired generating units. Thus natural gas has gained a significant share in the portfolio of electricity generation fuel resources, and it is... 

Natural gas power plant installed in power system as rapid start unit. In the recent decades, with increasing in the number of gas generating units in the world, consideration of natural gas transmission network in optimal solution of security-constrained unit commitment (SCUC) become a non-negligible problem. The gas transmission grid constraints integrated into the scheduling of thermal units in the proposed model for minimizes power system operating cost. In a power plant transmission of natural gas to power plant is very important because congestion in natural gas pipeline increases. This model could consider natural gas storage tank in gas transmission network as decision variable.... 

Providing more choices to customers for determining the cost of their required reliability levels is one of the most important targets of restructured power system. Centralized management of reliability in Vertically Integrated Utility (VIU) applying the same policies to different customers is replaced with decentralized management allowing customers to participate in reliability management based on their required reliability levels. In this thesis, impact of emergency demand response programs, interruptible load contract and wind farms on the long-term security constrained unit commitment has been studied. Random outages of generators and transmission lines, load forecast inaccuracies as...