Study Of Intelligent Under Frequency Load Shedding Modeling And Simulation

Under frequency load shedding as the last defense of the power system, caneffectively prevent the frequency of crashes and widespread blackouts. Based onPMU, Wide area measurement system can achieve real-time monitoring of powersystem dynamics in a unified space-time coordinates. WAMS offers the possibility forunder frequency load shedding that decentralized control is replaced with centralizedcontrol, and global optimization. In recent years, smart grid and demand responsetechnology become research hotspots. Controllable thermostatically controlled loadsget widespread attention for the characteristics of temperature-controlled storagefeature, easy to control and fast response.This paper addresses on adaptive under frequency load shedding method basedon household controllable thermostatically controlled loads. Main work is as followed.Firstly, this paper studies control processes and theoretical basis of under frequencyload shedding, including its existing types and the advantages and disadvantages ofeach type, static and dynamic characteristics of the system frequency, aspects to beconsidered in load shedding device settings. Secondly, it studies principles andfunctions of smart grid and demand response technology, analyses operatingcharacteristics of household controllable thermostatically controlled loads, establishits mathematical model and propose its control methods. Finally, it propose a newadaptive under frequency load shedding method based on household controllablethermostatically controlled loads, considering its power adjustable features. This newcontrol method is an improvement of the existing adaptive load shedding based onWAMS. Besides, the proposed load shedding is simulated using PSAT software andthe result is analyzed.