铝合金薄板交流CMT焊接过程能量分配研究

以1060铝合金为对象,采用交流CMT焊接技术进行平板堆焊,研究了交流CMT焊接过程中用于母材熔化能量和焊丝熔化能量的精确控制。结果表明,通过变换EN、EP的数值及比例可以对交流CMT焊接过程中的能量分配进行控制进而控制焊缝成形。当EN/EP=1∶1时,焊接过程中输入的总能量不变,由于EN值的变化使对母材连续热输入的方式发生改变,会使熔深余高变化,随着EN个数的增加、熔深逐渐减小、余高逐渐增加。当EN+EP=14时,变化EN的个数。当EN=0时相当于直流反接,此时焊丝的熔化系数最小,熔深最大,余高最小;随着EN的增加,焊缝熔深减小,对焊丝的热输入逐渐增加,余高增加。

纯电动汽车800 V高电压复合电源能量分配策略研究

基于逻辑门限控制策略,将动力电池和带有理想开关的DC/DC变换器串联,并将串联后的系统与超级电容并联,形成新型复合电源系统,利用低成本小容量超级电容,增大充放电电压,减少系统线路上的能量损耗。同时,采用Matlab/Simulink仿真平台,搭建控制策略模型,结合基于ADVISOR2002建立的复合电源纯电动汽车模型,进行联合仿真。分析结果表明:所提出的新型复合电源能量分配控制策略明显提升了电池续航能力,降低了工作电流,能够有效地延长电池的使用寿命。

混合动力车辆机电复合驱动技术综述

机电复合驱动系统的机械桥和电驱桥可独立驱动或协同驱动车辆,能有效解决超大型发射平台发动机功率不足和现役发射平台动力性提升以及行驶可靠性提高等难题.文中论述了混合动力车辆的分类及混合动力驱动构型的特点和优势,分析了机电复合驱动车辆能量分配控制、协调控制及稳定性控制的研究现状,总结了整车能量控制、稳定性控制和驱动电机及其控制等关键技术及其发展趋势,分析了车辆机电复合驱动技术的应用前景.

Attitude control allocation strategy of high altitude airship based on synthetic performance optimization

This paper presents a method for solving the attitude control problem of high altitude airship (HAA) with aerodynamic fin and vectored thruster control. The algorithm is based on the synthetic optimization of dynamic performance and energy consumption of airship. Firstly, according to the system overall configuration, the dynamic model of HAA was established and the HAA linearized model of longitudinal plane motion was obtained. Secondly, using the classic PID control theory, the HAA attitude control system was designed. Thirdly, through analyzing the dynamic performance of airship with fin or vectored thruster control, the synthetic performance index function with different weighting functions was determined. By means of optimizing the obtained performance index function, the attitude control of high altitude airship with good dynamic performance and low energy consumption was achieved. Finally, attitude control allocation strategy was designed for the airship station keeping at an altitude of 22 km. The simulation experiment proved the validity of the proposed algorithm.