Some Issues On The Active Power Dispatch And Decision-Making Under The Environment Of The Electric Power Market

Under the environment of electric power market, the traditional active power dispatchchanges constitutionally. It shows that the dispatchers not only need to minimize the operationcost, but also need to pursue electric power trade cost and the index of security and reliabilityaccording to the market economy. For this reason, the traditional active power dispatch shouldbe extended with the consideration of the various cost and loss in the objective function. Thisis a multiple objective functions problem. In order to easily make reasonable decision in theelectric power market, developing a flexible model and the associated algorithm are veryimportant for this problem. This dissertation presents the generalized active power optimalpower flow model and solution method that formulates the load flow equation by using thenetwork flow model, combines the interior point methods, looking ahead technique and sparsemeans. The result obtained in a test example shows the effectiveness of the proposed method The electricity market is a kind of imperfect competitive market due to its specialcharacteristics. The degree used to measure the imperfect competition is defined as the marketpower index. The Lerner index, the HH index and the ratio index between the total demandand total available supply capacity are firstly reviewed and analyzed. The mechanisminfluencing the market power index between the unit ramp rate constraints and the marketpower index mentioned above is explained. Due to the contradiction between the effectiveresponse ability of unit and the demand variation during the period studied, the market powerindex does not vary monotonously with time, and any unit has the possibility to produce themarket power. The conditions that should be considered in studying the market power indexare pointed out. ISO is one of the cores in the electric power market. It is a key task of ISO that the pricesystem satisfied various constraints should be decided in electric power market. The stabileequilibrium of the price system is very important to the development of electric powerindustry. From this point of view, based on the simplified model of ISO, this dissertationanalyzes the behaviors of power suppliers and power demanders, and deduces the surplus IIIratio expressions as well as the bidding equilibrium condition of power suppliers and powerdemanders. Then, the reasons producing market power are analyzed. Finally, the concept ofprice system stable equilibrium is presented based on the cobweb model and the applicationof the cobweb model in the calculation of electric power price is introduced. Due to the coupling, difference and imbalance in both the terrain and the time domain,there are many conflict problems in electric power system operation dispatch, such as securityvs. cost, congestion and interruption and so on. The optimality and decision making ofbalancing supply and demand must be a tradeoff problem between rigid and flexible. Fromthis point of view, the dissertation dissertates the conflict mechanism among supply anddemand, proposes an idea and a collective method to solve this problem. The dissertation alsopresents a theory frame for electric power system operation dispatch with looking aheadability. The proposed theory frame has the properties of both rigid optimality and flexibledecision-making. This theory frame contains the following issues: mining the origin of therestriction between the objectives and the constraints, pursuing the characteristic pattern of theconstraint region, providing the rigid optimal means combining electrical law and moderntechniques; analyzing the reasons of transmission ability existed asymmetry, deriving thestrategy of weakening the asymmetry, demonstrating the tradeoff rule of cost and security,providing the transmission ability judging mechanism which can reflect the cost and securityproportionately, exploring the meaning of the equivalent electric...