To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed c...To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed control model provides continuity of acceleration, which avoids the intense vibration in high speed NC machining. Based on the discrete characteristic of the data sampling interpolation, the acc/dec control discrete mathematical model is also set up and the discrete expression of the theoretical deceleration length is obtained furthermore. Aiming at the question of hardly predetermining the deceleration point in acc/dec control before interpolation, the adaptive acc/dec control algorithm is deduced from the expressions of the theoretical deceleration length. The experimental result proves that the acc/dec control model has the characteristic of easy implementation, stable movement and low impact. The model has been applied in multi-axes high speed micro fabrication machining successfully.展开更多
To develop the pressure control algorithm for active braking of adaptive cruise control（ACC） system,a test bench with real parts of the tested vehicle is built.With the dynamic analysis of the active braking actuato...To develop the pressure control algorithm for active braking of adaptive cruise control（ACC） system,a test bench with real parts of the tested vehicle is built.With the dynamic analysis of the active braking actuators,it is demonstrated that different duty of pulse-width modulation（PWM） signals could control the pressure changing rate of the wheel cylinder.To obtain that signal,a modified proportional-integral-differential（PID） control algorithm is developed using the variable parameter method,the control value reset method,the dead zone method and the integral saturation method.Experimental results show that the delay and overshoot of the pressure response could be reduced considerably using the modified PID algorithm compared with the conventional one.The proposed pressure control algorithm could be used for the further development of the ACC＇s controller.展开更多
区域能源中心(districtenergycentre,DEC)是多能流耦合的枢纽,主要实现多能流在区域级的优化传输和分配。随着能源市场管制的放松,以能源价格为调节手段引导需求侧进行互动响应有利于提升DEC的优化潜力。该文首先基于能量枢纽模型,建立...区域能源中心(districtenergycentre,DEC)是多能流耦合的枢纽,主要实现多能流在区域级的优化传输和分配。随着能源市场管制的放松,以能源价格为调节手段引导需求侧进行互动响应有利于提升DEC的优化潜力。该文首先基于能量枢纽模型,建立DEC的稳态能量流方程,探究功率平衡视角下的需求响应机理。考虑到价格调控下能源需求在时间上和类型上可相互转移,引入广义价格型需求侧响应(price based generalized demand response,P-GDR)的概念。同时,基于价格弹性及离散选择模型对P-GDR下能源需求的时空转移特性进行建模。并在此基础上建立DEC日前最优经济调度的混合整数非线性规划模型,通过广义Benders理论对其进行解耦求解。算例结果表明,考虑P-GDR有利于减少能源负荷峰谷差,并提高新能源消纳能力。此外,P-GDR下考虑能源负荷的可替代性更加符合用户行为实际,降低用户的能源购置成本。展开更多
基金the Hi-Tech Research and Development Pro-gram (863) of China (No. 2006AA04Z233)the National NaturalScience Foundation of China (No. 50575205)the Natural ScienceFoundation of Zhejiang Province (Nos. Y104243 and Y105686),China
文摘To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed control model provides continuity of acceleration, which avoids the intense vibration in high speed NC machining. Based on the discrete characteristic of the data sampling interpolation, the acc/dec control discrete mathematical model is also set up and the discrete expression of the theoretical deceleration length is obtained furthermore. Aiming at the question of hardly predetermining the deceleration point in acc/dec control before interpolation, the adaptive acc/dec control algorithm is deduced from the expressions of the theoretical deceleration length. The experimental result proves that the acc/dec control model has the characteristic of easy implementation, stable movement and low impact. The model has been applied in multi-axes high speed micro fabrication machining successfully.
基金Supported by the Ministerial Level Advanced Research Foundation(40401040302)
文摘To develop the pressure control algorithm for active braking of adaptive cruise control（ACC） system,a test bench with real parts of the tested vehicle is built.With the dynamic analysis of the active braking actuators,it is demonstrated that different duty of pulse-width modulation（PWM） signals could control the pressure changing rate of the wheel cylinder.To obtain that signal,a modified proportional-integral-differential（PID） control algorithm is developed using the variable parameter method,the control value reset method,the dead zone method and the integral saturation method.Experimental results show that the delay and overshoot of the pressure response could be reduced considerably using the modified PID algorithm compared with the conventional one.The proposed pressure control algorithm could be used for the further development of the ACC＇s controller.
文摘区域能源中心(districtenergycentre,DEC)是多能流耦合的枢纽,主要实现多能流在区域级的优化传输和分配。随着能源市场管制的放松,以能源价格为调节手段引导需求侧进行互动响应有利于提升DEC的优化潜力。该文首先基于能量枢纽模型,建立DEC的稳态能量流方程,探究功率平衡视角下的需求响应机理。考虑到价格调控下能源需求在时间上和类型上可相互转移,引入广义价格型需求侧响应(price based generalized demand response,P-GDR)的概念。同时,基于价格弹性及离散选择模型对P-GDR下能源需求的时空转移特性进行建模。并在此基础上建立DEC日前最优经济调度的混合整数非线性规划模型,通过广义Benders理论对其进行解耦求解。算例结果表明,考虑P-GDR有利于减少能源负荷峰谷差,并提高新能源消纳能力。此外,P-GDR下考虑能源负荷的可替代性更加符合用户行为实际,降低用户的能源购置成本。
