Study On Gas Turbine-Combined Heat And Power In Distributed Energy Systems

Distributed energy is a new direction in energy field across the globe. It usually can produce more than one kind of energy form and thus can be used for at least two functions. It plays an important role in cold, combined heat and power systems. The proportion of power generation using CHP is growing quickly due to its so many merits such as high efficiency, compact size, environmental benefits, flexible when load changes, low vibration level, high reliability, low transmission loss, low initial investment cost and so on. As an important motivity equipment in distributed energy systems, GT-CHP technology has developed greatly in recent years which uses natural gas as fuel. The systems not only produce electric power, but thermal energy as well, the latter of which is produced from the burning of exhaust gas in HRSG. Because of this, a high total thermodynamic efficiency can be gotten. At the same time, it is also beneficial for society, energy-saving and environment. The GT-CHP systems can be used separately to supply two kinds of energy forms to a building or residential areas. More important, as a kind of distributed generator, it can be together with other distributed generators to meet multiple users' various needs, where it is just a subsystem.There are two traditional operation modes in GT-CHP systems, which are "Utility demand first" and "Heating demand first". Both of them have their own advantages and disadvantages. Which one to choose in a specific occasion depends on which load is more important to users and has other distributed generators to be on standby. Thus, for a GT-CHP system, the key problem is to meet supply and demand balances in different hours and for different users. That is to say, for the purpose of getting the optimal energy utilization efficiency, measures must be taken to solve the inconsistencies between cogeneration systems' produced heat/power ratio and heat demand/power demand ratio from users.The final CHP system will work together with other distributed generators in Energy Management Systems (EMS). In order to offer a common interface, all the distributed models must be set according to part 301 of the IEC-61970 standard, which is Common Information Model (usually CIM for short). So in the fourth chapter, the CIM model for gas-turbine generating unit is set, and also the designing scheme of relevant software is given.