Synchronized Phasor Measurement Unit (PMU)
Electrical Control and Protection II
Assignment
Introduction:
More recent technological advancements in microprocessor relays, combined with GPS receivers for synchronization and accurate time stamping, is providing users advanced relay systems with synchronized measurements, called synchrophasor measurements Synchronized .Wide Area measurements (WAMs) is a relatively modern practice universal in the operation and control of electric power transmission. It consists of making synchronized measurements of phasor quantities of voltages and currents at several points spaced hundreds or thousands of kilometers points. Phasor Measurement Unit (PMU) technology provides phasor information (both magnitude and phase angle) in real time. The importance of data provided by PMUs has been well recognized after a number of major blackouts in many power systems in different parts of the world. PMU is an important component of WAMs.
Synchronized measurements components:
Synchronized measurements of voltages and currents are done by Phasor measurement Units (PMUs). Each PMU has three essential components.
• GPS signal receiver
• Data acquisition module
• Communication module
The GPS signal receiver consists of an aerial and receiver circuits, which detect the 1PPS (pulse per second) and a time tag consisting of the year, day, hour, minute, and second [1].
Synchronizing signal from the GPS satellites. This signal is used to correct for drifts in a local clock oscillator, which keeps the basic time in the PMU. The local clock provides the timing signals to the data acquisition module to sample the voltage and current signals with correct time stamps. These samples are digita...
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The second method of measuring three phase power is the useful for both balanced and unbalanced loads. By connecting a wattmeter with its current probes in series with red phase and volt probes between red and yellow phase. The second wattmeter should be connected with its current probes in series with the blue phase and the volt probes between the blue and yellow phases. By adding these two values together there total power for the system can be
...red testing at Lectromec showed that contaminants, such as water, lavatory fluid, and metal shavings, can create a bridge that can allow energy to unintentionally transfer between wires with cracked or damaged insulation for as long as 25 minutes without tripping circuit breakers. Specifically, the totalizer gauge’s wires on TWA Flight 800 had been improperly soldered together and had subsequently cracked apart, providing another opportunity for an explosive short circuit. During examination of the gauge at Honeywell, it was determined that electrical energy would cross the crack in the solder between the connector pins when slightly more than 270 volts (less than is used in lighting circuits) was applied to one of the pins. Thus, a short circuit from a higher-voltage wire to any corouted FQIS wiring could result in excess energy being transferred to the CWT.
Greater shift towards smart grids, smart metering and building automation: Smart grids helps in intelligent distribution resulting in minimal losses whereas measurement and reporting of consumption in real time is achieved by smart meters.
Siwakoti P.Y., Graham E.T., Design of FPGA-controlled Power Electronics and Drives Using MATLAB Simulink, Macquarie University, Australia, 571- 577, 2013.
My knowledge of engineering is reasonable and includes transformer substations, power plants, power distribution and transmission systems, industrial motor control and PLC programming, protective relay coordination, FACTS devices, grounding systems, Matlab programming and project management. In addition, I possess practical experience performing power flow, short-circuit and relay coordination analyses while using a power system modelling software such as ETAP, EDSA, DigSilent and CYME. Consequently, the aforementioned experience and solid engineering education along with your training will allow me to provide support to operating and new
On August 14th, 2003, a major blackout swept across portions of the northeastern United States and Canada. It was reported that a series of equipment outages in the Midwest led to uncontrolled cascading outages of power transmission lines and generators serving parts of the Northeast, Midwest and Canada. Automatic protective systems operated to open circuits and shut down power plants to prevent further spread of the outages. This is very similar to what happened in The Great Northeast Blackout of 1965. In both situations, the “grid system” shut down one generator in line at a time to protect a surge from the station before it.
...ial approaches which are Normal Accident and HROs, although it seems certain that both of them tends to limit the progression that can contribute toward achieving to highly protective systems. This is because the scope of the problems is too narrow and the potential of the solutions is too limited as well. Hence, Laporte and Consolini et.al., (1991) as cited in Marais, et.al., (2004) conclude that the most interesting feature of the high reliability organization is to prioritize both performance and security by the managerial oversight. In addition, the goal agreement must be an official announcement. In essence, it is recommended that there is a continuing need in the high risk organizations for more awareness of developing security system and high reliability environment in order to gain highly successful method to lower risk in an advance technology system.
The basic concept of how the Global Positioning System works sounds extremely simple, however what goes on behind the scenes includes processes that become particularly confounding...
United States. Sandia National Laboratories. (2012, April 24). National Supervisory Control And Data Acquisition (SCADA). Retrieved from http://energy.sandia.gov/?page_id=859
The emergence of the Microgrids came after realizing that the architecture of the electricity grid existing nowadays (Figure 1) is getting obsolete, since it is based on the idea of a top-down system, which is predicated on unidirectional energy flows. [ASMUS09]
For example, in a home equipped with a backup generator and an ATS, when an electric utility outage occurs, the ATS will tell the backup generator to start. Once the ATS sees that the generator is r...
For the prevantion of the electricity blackout we need to build smart power grid. A modernized electrical grid that uses analog or digital information and communications technology to gather and act on information, such as information about the behaviours of suppliers and consumers is known as a smart grid. This is used to improve the efficiency, reliability, economics, and sustainability of the production and distribution of electricity in an automated fashion[12]. The important aspects of smart grid is to electronic power conditioning and control of the production and distribution of
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3. Brain, Marshall, and Tom Harris. "How GPS Receivers Work." 25 September 2006. HowStuffWorks.com. 01 June 2010.
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