ABB Automation World 2012, V. Knazkins, 6 June 2012 Smart Grids and Modern Excitation Systems June 4, 2012 Slide 1
Agenda The Smart Grid The Modern Excitation Systems Smart Grid Enablers An Example June 4, 2012 Slide 2
The Smart Grid The Smart Grid can in brief terms be defined as a complex structure encompassing power systems, electrical and informational infrastructures, governments, electricity markets, and the links between them. This definition echoes the definition of a system, as defined by the theorists. It is believed that the main driver for the Smart Grid technology in Europe is the so-called European Commission s Communication of November 13 2008 Energy Efficiency: delivering the 20% target. 2008 11 13 20% In short, the EU s 20-20-20 goal is: 20-20-20 : 20% increase in energy efficiency, 20%, 20% reduction of CO 2 emissions, and 20% 20% renewables by year 2020. June 4, 2012 Slide 3 2020 20%.
The Smart Grid In contrast, the U.S.A. government set different goals for the electricity sector: : 10% of electricity must be produced by renewables by end of 2012 2012 10 25% of electricity must be produced by renewables by end of 2025 2025 25 According to the U.S. Department of Energy a smart grid will: : 1. Optimize asset utilization and operating efficiency. 2. Accommodate all generation and storage options. 3. Provide power quality for the range of needs in a digital economy. 4. Anticipate and respond to system disturbances in a self-healing manner. June 4, 2012 Slide 4
The Smart Grid 5. Operate resiliently against physical and cyber attacks and natural disasters. 6. Enable active participation by consumers. 7. Enable new products, services, and markets.. June 4, 2012 Slide 5
The Smart Grid 5. Enable active participation by consumers. 6. Enable new products, services, and markets. June 4, 2012 Slide 6
The Modern Excitation Systems According to the IEEE Standard 421.1-2007, the excitation system is the equipment providing field current for a synchronous machine, including all power, regulating, control, and protective elements. IEEE 421.1-2007, June 4, 2012 Slide 7
The Modern Excitation Systems UNITROL 6000 is the state-of-the-art excitation system, which arguably is the most advanced excitation system in the world. UNITROL 6000 June 4, 2012 Slide 8
The Modern Excitation Systems A modern excitation system has to carry out a number of functions: : It must provide direct current to the synchronous machine field winding to control the terminal voltage by adjusting the field current. It must provide limiting and protective functions as required to prevent damage to the generator, itself, and other equipment. It must provide operating flexibility. It must provide reliability, availability, desired level of redundancy, and internal and external fault detection. It must also perform control and protective functions essential to the satisfactory performance of the power system by controlling the field current (e.g., PSS). PSS June 4, 2012 Slide 9
Smart Grid Enablers The modern excitation systems are examples of very matured and advanced technology, that has been forged over a number of decades. When the Smart Grids will become common place, the electric power will be produced by generators utilizing various energy sources, such as wind power, solar energy, bio-fuel, etc. Nevertheless, the conventional generator will continue play an important role in providing balancing power. Thus, the modern excitation systems must contribute to the strategic goals set for the Smart Grid. Therefore, the modern excitation systems will take the niche of Smart Grid Enablers. June 4, 2012 Slide 10
Smart Grid Enablers The modern excitation systems are foreseen to contribute to: : 1. Increasing the efficiency of the Smart Grid 2. Proliferation of renewable energy sources. This can be achieved by 1. Providing grid stabilizing functions 2. Enhancing the operating data communication with the control center 3. Increasing the excitation system reliability and thus the overall grid reliability. June 4, 2012 Slide 11
Smart Grid Enablers Most of the modern excitation systems already now provide stabilizing functions, e.g., PSS; however, ABB goes one step further and manufactures the Multiband PSS (IEEE PSS4B) which is capable of reducing the global oscillations in the grid.., PSS;, ABB PSS (IEEE PSS4B) Thus, the overall reliability of the grid is increased. Another example: the United States Patent US 7973427 B2 CONVERTER CONTROL UNIT issued August 29, 2008. : US 7973427 B2 8 29, 2008. June 4, 2012 Slide 12
Smart Grid Enablers This patent presents the new idea of combining the excitation system with a wide-area monitoring unit. This patent allows building excitation systems of new generation which will assist in Riding through severe large-scale disturbances Damping global oscillations Facilitating real-time data communication to the control centers. Here operational data, availability, grid conditions, stability margins, etc. can be transferred to the control center. Increasing the capacity of various transmission corridors in the grid and thus enabling penetration of more renewable energy in the grid and also supporting the electricity markets. June 4, 2012 Slide 13
An Example The business unit ATPE (Turgi) and the Corporate Research Center (Dättwil) conducted a study which explored the use of the patent for the wide-area grid stabilization. ATPE(Turgi) (Dättwil) In the study a new type of system stabilizer was used which allowed for simultaneous stabilization of 2 oscillation modes in the Nordic power system. 2 It was shown that the idea captured in the patent enables the design of very effective controllers which allowed to essentially increase the stability margin in the power system. For instance, using the existing power system stabilizers it was not possible to achieve such a high quality performance. For the Smart Grids such controllers and technology will allow for higher penetration levels of renewables which are of intermittent nature, e.g., wind or solar power. June 4, 2012 Slide 14