Its operation frequency is 1 . 38mhz , with an integration of a power mosfet whose breakdown voltage is up to 50v . the allowable input voltage ranges from 2 . 7v to 5 . 5v and its output voltage can be programmed between - 2v and - 15v , additionally , the output current is in a 200ma range in typical application . to avoid the poor efficiency of the pwm control scheme at light load , a skip - cycle - mode operation is introduced that allows system ’ s efficient operation at the light load 该电路工作频率为1 . 38mhz ,内部集成耐压50v的功率mosfet ,输入电压范围2 . 7v 5 . 5v ,输出电压可在- 2v - 15v间连续可调,典型工作条件下输出电流在200ma之内;同时,在轻负载下提供跳周期模式,具有很高的待机效率。
Since kamen and vagena , many researchers have discussed it in theory and experiment method . the main content in this paper is to set forth the slamming press calculations in dnv rules , gl rules and lr rules and the requirements for slamming strengthened bow structure and some comparisons ; slamming strengthened bow structure design for a bulk is carried out using dnv rules , and comparisons among several design schemes is carried through when heavy loading draft status replaces light loading draft status in practice . the results from above have been applied in ship production ; it is significant for ship structure improvement latter to calculate slamming press with direct calculation method , and then to design bow structure with dnv rules 本文的主要内容是分别阐述dnv 、 gl 、 lr三种规范对底部砰击压力计算及底部砰击加强结构设计的一般要求并进行一些分析比较:用dnv规范对某型船( 27000t散货船)进行具体的底部砰击加强结构设计,并就实际生产中产生的重载吃水状态改轻载吃水状态而出现的几种设计方案进行比较,其具体结果现已用于实际生产;用直接计算法确定砰击压力,再用dnv规范进行底部结构设计,对于后续船的改进均有指导意义。
And it can be controlled running at a rating slip , when its efficiency is the highest . then , simulation model of lim vector control system is constructed , which is proved accurate by simulation results under different speed and different load . and it is concluded that lim efficiency is lower under light load or low speed 其次,建立了考虑边端效应的直线感应电机矢量控制系统的仿真模型,不同速度和负载下仿真结果验证了模型的有效性,得到了电机在轻载或低速运行时效率较低的结论。
At light loads , the architecture allows the chip to “ skip ” cycles to reduce power dissipation . in the circuit design , the basic principle and small signal model of the boost power stage are given at first , and then the stability and small signal model of the control loop are also analyzed , finally , the whole chip architecture and sub - block parameters are presented according to the application requirements 在电路设计中,首先阐述了升压型直流转换器的功率输出级的拓扑结构、基本原理、小信号模型,然后分析了电流模式控制回路的稳定性及小信号模型,最后根据应用要求进行了电路的总体架构设计,完成了每个子电路的各种参数的分析、计算。
The switch power will operate at ccm condition when circuit is set to pwm mode . when pfm mode is selected for the operation mode , the switch power will still operate at pwm condition with the high load , the system will cancel the pwm mode and enter the pfm mode only when the load is drop to a certain threshold to boost the operation efficiency at light load , make the ic has high efficiency within wide load range 选择pwm模式,开关电源将工作在ccm模式下;选择pfm模式,在负载较高的情况下,开关电源仍然工作于pwm模式,只有当负载降低到一定程度时,开关电源才退出pwm模式,而按照pfm工作模式操作,跨过一部分时钟周期,降低频率相关功耗,以提高轻负载时低效率的问题,使得开关电源在很宽的负载范围内都具有高效率。
A consummate node load computing method is put forward after synthesizing various of load index literature . by using the arithmetic of dynamic adjustive load banlance and introducing the concept of double thresholds , every node can rapidly transfer load in weight load and in idlesses or light load it can rapidly transfer load 本文中在综合各种负载指标的文献后提出了较为完善的节点负载计算方法,并且引入双阈值的概念提出了具有特色的动态自适应负载平衡算法,使各节点在空闲或轻负载时能够主动地向服务器申请,在重负载时能更快地进行负载迁移。
A new modulation mode , which is the mode of pulse skip modulation ( psm ) , can overcome the above disadvantages of pwm and pfm . simulation results show that psm has many merits such as high efficiency at light load , high response speed , robustness and simple implement for circuit design 现今一种全新的调制方式? ?脉冲跨周期调制模式( psm , pulseskipmodulation )则正好可以弥补上述两种模式的缺点,经过大量仿真研究表明,该调制模式具有轻载时效率高、响应速度快、鲁棒性强、电路易于实现等特点。