A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation ...A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation of rotary valve orifice reveals that orifice exists the two-throttle phenomenon.According to the finding,the revised flow area model was established.Vibration waveforms analysis was carried out by means of mathematic model and the related experiments were validated.Furthermore,as a new analysis indicator,saturation percentage was introduced first.The experimental results indicate that the revised flow area model is more accurate compared to the original one,and vibration waveforms can be optimized through suitable spool parameters and the revised cylinder structure.展开更多
This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC （static var compensator）-based damping controllers. Each machine or generator...This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC （static var compensator）-based damping controllers. Each machine or generator is considered as a subsystem and its interaction with the remaining part of the system, the SVC inclusive, is modeled as a quadratic function of the active power delivered by the generator. Stable manifold is constructed for each excitation controller and based on that, an effective damping controller is derived. A lead-lag compensator is employed as a supplementary controller for the SVC. PSO （particle swarm optimization） algorithm is effectively utilized to simultaneously tune the parameters for the excitation damping controller（s） and the SVC supplementary controller. The coordination of the controllers effectively dampens the power angle oscillation and regulates the generator terminal voltage when a fault occurs. Simulation results are obtained by using the PAT （power analysis toolbox） for a SMIB （single machine infinite bus） system and a two area power system.展开更多
基金Project(51275499)supported by the National Natural Science Foundation of ChinaProject(2013CB035404)supported by the National Basic Research Program("973" Program)of ChinaProject(51221004)supported by the Science Fund for Creative Research Groups,National Natural Science Foundation of China
文摘A new electro-hydraulic exciter that consists of rotary valve and micro-displacement double-functioned hydraulic cylinder was proposed to realize different kinds of waveforms.Calculated fluid dynamics(CFD) simulation of rotary valve orifice reveals that orifice exists the two-throttle phenomenon.According to the finding,the revised flow area model was established.Vibration waveforms analysis was carried out by means of mathematic model and the related experiments were validated.Furthermore,as a new analysis indicator,saturation percentage was introduced first.The experimental results indicate that the revised flow area model is more accurate compared to the original one,and vibration waveforms can be optimized through suitable spool parameters and the revised cylinder structure.
文摘This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC （static var compensator）-based damping controllers. Each machine or generator is considered as a subsystem and its interaction with the remaining part of the system, the SVC inclusive, is modeled as a quadratic function of the active power delivered by the generator. Stable manifold is constructed for each excitation controller and based on that, an effective damping controller is derived. A lead-lag compensator is employed as a supplementary controller for the SVC. PSO （particle swarm optimization） algorithm is effectively utilized to simultaneously tune the parameters for the excitation damping controller（s） and the SVC supplementary controller. The coordination of the controllers effectively dampens the power angle oscillation and regulates the generator terminal voltage when a fault occurs. Simulation results are obtained by using the PAT （power analysis toolbox） for a SMIB （single machine infinite bus） system and a two area power system.
