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Assignment 10:Bulk Power System Disturbances and Disturbance Mitigation & Questions on Getting Projects BuiltEE 444: Power Systems Technology (Fall 2017)Date: 10/20/17Presented by: Shardul SinghAnswer 1: Based on the Presentation Lecture by Mr. Ron Lavorn and some of the own research on the research. Four types of Power Disturbances and their definitions as per the lecture by Mr. Ron LavornSub-Transient Disturbances: Duration of these disturbances is from sub-cycles to cycles. Lightning strikes and various types of switching transients. Major concern is ability of equipment to withstand disturbance without damage and failure. Some of the sub-Transients are listed below: 1.Transformer switching (in rush) (Figure 1): A transformer draws inrush current that can exceed saturation current at power up. The Inrush Current affects the magnetic property of the core. This happens even if the transformer has no load with its secondary open. The magnitude of the inrush current depends on the point on the AC wave the transformer is switched on. 2.Lightning (Figure 2):Lightning-caused faults on a utility power system can lead to voltage sags affecting customers over a wide area or high transient voltages resulting in equipment failures on the power system and in customer facilities. Categorizing thecause of faults is critical when using the information to prioritize maintenance and repairs to the power system3.Capacitor Switching (Over voltage + IEEE standards) (Figure 3): Capacitor banks applied within distribution substations typically consists of one to four banks of switched capacitors. The switched banks are designed to come on and off automatically based on power factor, vars, and/or voltage. Due to load variations, a number of switching operations will occur daily. Each switching event is followed by a low-frequency decaying ring wave transient that can result in power quality problems for nearby industrial and commercial loads.