In petawatt laser system, the gratings.used to compose pulse compressor are very large in size which can be only acquired currently by arraying small aperture gratings to form a large one instead, an approach referred...In petawatt laser system, the gratings.used to compose pulse compressor are very large in size which can be only acquired currently by arraying small aperture gratings to form a large one instead, an approach referred to as grating tiling. Theory and experiments have demonstrated that the coherent addition of multiple small gratings to form a larger grating is viable, the key technology of which is to control the relative position and orientation of each grating with high precision. According to the turin factors that affect the performance of the grating tiling, a 5-DOF ultraprecision stage is developed for the grating tiling experiment. The mechanism is formed by serial structures. The motion of the mechanism is guided by flexure hinges and driven by piezoelectric actuators and the movement resolution of which can achieve nanometer level. To keep the stability of the mechanism, capacitive position sensors with nanometer accuracy are fixed on it to provide feedback signlas with which to realize closed-loop control, thus the positioning.precision of the mechanism is within several nanometers range through voltage control and digital PID algorithm. Results of experiments indicate that the performance of the mechanism can meet the requirement of precision for grating tiling.展开更多
Thermostatically controlled loads(TCLs)are one of the best candidates to participate in direct load control(DLC).However,little attention is given to the parameter optimization of the TCLs control system due to the co...Thermostatically controlled loads(TCLs)are one of the best candidates to participate in direct load control(DLC).However,little attention is given to the parameter optimization of the TCLs control system due to the complexity of the TCLs’dynamics.In this paper,the parameters of the feedback control system based on the direct compressor control mechanism(DCCM)are optimized using the modified state-queuing(SQ)model,which can provide good characterizaton and greatly simplifies the dynamics of the TCLs.The simulation results verify the effectiveness of the proposed method.展开更多
基金This project is supported by Nanotechnology Promotion Center, Science and Technology Commission of Shanghai Municipality, China (No. 0359nm004)
文摘In petawatt laser system, the gratings.used to compose pulse compressor are very large in size which can be only acquired currently by arraying small aperture gratings to form a large one instead, an approach referred to as grating tiling. Theory and experiments have demonstrated that the coherent addition of multiple small gratings to form a larger grating is viable, the key technology of which is to control the relative position and orientation of each grating with high precision. According to the turin factors that affect the performance of the grating tiling, a 5-DOF ultraprecision stage is developed for the grating tiling experiment. The mechanism is formed by serial structures. The motion of the mechanism is guided by flexure hinges and driven by piezoelectric actuators and the movement resolution of which can achieve nanometer level. To keep the stability of the mechanism, capacitive position sensors with nanometer accuracy are fixed on it to provide feedback signlas with which to realize closed-loop control, thus the positioning.precision of the mechanism is within several nanometers range through voltage control and digital PID algorithm. Results of experiments indicate that the performance of the mechanism can meet the requirement of precision for grating tiling.
基金This work was supported in part by the National Natural Science Foundation of China(51707099)the University Science Research Project of Jiangsu Province(16KJB470009)China Postdoctoral Science Foundation(2017M611859).
文摘Thermostatically controlled loads(TCLs)are one of the best candidates to participate in direct load control(DLC).However,little attention is given to the parameter optimization of the TCLs control system due to the complexity of the TCLs’dynamics.In this paper,the parameters of the feedback control system based on the direct compressor control mechanism(DCCM)are optimized using the modified state-queuing(SQ)model,which can provide good characterizaton and greatly simplifies the dynamics of the TCLs.The simulation results verify the effectiveness of the proposed method.
