A few multi-terminal direct current(MTDC)systems are in operation around the world today. However,MTDC grids overlaying their AC counterpart might a reality in a near future. The main drivers for constructing such dir...A few multi-terminal direct current(MTDC)systems are in operation around the world today. However,MTDC grids overlaying their AC counterpart might a reality in a near future. The main drivers for constructing such direct current grids are the large-scale integration of remote renewable energy resources into the existing alternative current(AC) grids, and the promotion and development of international energy markets through the socalled supergrids. This paper presents the most critical challenges and prospects for such emerging MTDC grids,along with a foreseeable technology development roadmap,with a particular focus on crucial control and operational issues that are associated with MTDC systems and grids.展开更多
Grid-connected power converters,which are frequently used to link renewable generation plants with the grid,are required to provide a better functionality for large scale integration of renewables.They are expected to...Grid-connected power converters,which are frequently used to link renewable generation plants with the grid,are required to provide a better functionality for large scale integration of renewables.They are expected to be gridfriendly,or even grid-supportive,instead of simply grid-feeding or grid-demanding.This paper designs a synchronous power controller for grid-connected converters in detail,emulating the electromechanical characteristics of synchronous machines and improving even its actual performance,as it is based on a virtual approach.Based on this design,the grid-interfacing units are capable of showing inertia,damping,and droop characteristics as synchronous machines and presenting thus a grid-supporting behavior.The detailed control design and experimental validation on a 10 kW laboratory setup acts as the main contribution of this paper,compared with the existing studies on generator emulation controls.展开更多
文摘A few multi-terminal direct current(MTDC)systems are in operation around the world today. However,MTDC grids overlaying their AC counterpart might a reality in a near future. The main drivers for constructing such direct current grids are the large-scale integration of remote renewable energy resources into the existing alternative current(AC) grids, and the promotion and development of international energy markets through the socalled supergrids. This paper presents the most critical challenges and prospects for such emerging MTDC grids,along with a foreseeable technology development roadmap,with a particular focus on crucial control and operational issues that are associated with MTDC systems and grids.
基金supported by the Spanish Ministry of Economy and Competitiveness under the project ENE2014-60228-R.
文摘Grid-connected power converters,which are frequently used to link renewable generation plants with the grid,are required to provide a better functionality for large scale integration of renewables.They are expected to be gridfriendly,or even grid-supportive,instead of simply grid-feeding or grid-demanding.This paper designs a synchronous power controller for grid-connected converters in detail,emulating the electromechanical characteristics of synchronous machines and improving even its actual performance,as it is based on a virtual approach.Based on this design,the grid-interfacing units are capable of showing inertia,damping,and droop characteristics as synchronous machines and presenting thus a grid-supporting behavior.The detailed control design and experimental validation on a 10 kW laboratory setup acts as the main contribution of this paper,compared with the existing studies on generator emulation controls.