The power circuit of the system adopts the voltage frequency conversion structure of ac - dc - ac , and is composed of the commutation circuit , filter circuit and intelligence power module ( pm15rsh120 ) . control circuit takes the dsp chip tms320lf2407 as core , including the pwm signal occurrence circuit , detect circuit of stator current and direct current voltage of generatrix , drive circuit of intelligence power module , detect circuit of speed , protect circuit of system etc . all of this builds the full digital vector control system of asynchronous motor 该系统的功率电路采用电压型的交-直-交变压变频结构,由整流电路、滤波电路及智能功率模块ipm ( pm15rsh120 )逆变电路构成;控制电路以dsp芯片tms320lf2407为核心,加上pwm信号发生电路、定子电流检测电路、直流母线电压检测电路、智能功率模块驱动电路、速度检测电路、系统保护电路等,构成了功能齐全的异步电机全数字化矢量控制系统。
Abstract : based on the basic concept of the revolving shell , the equation of the middle surface generatrix of the approximate ellipsoid portion of the ellipsoidal head is derived , the unwrapped area and the unwrapped diameter of the ellipsoidal head are calculated , the result is compared with that of derived from the real ellipsoid and that of calculated from the empirical equation , relative chart and code are given out , which could be used by manufactures for reference 文摘:根据回转壳体的基本概念，推导了椭圆封头的近似椭圆壳部分的中面母线方程，据此推导计算了椭圆封头的展开面积及展开圆直径，并根据椭圆壳几何形状推导的结果与经验公式所得结果进行了比较，给出了有关图表及计算程序，可供制造单位参考使用。
Based on the geometry characteristics of bertrand surfaces , the complicated surface conjugation issue can be discussed with their directrix line . according to the different generatrix line which can be divided into common plane curve , circular - arc curve and straight line , bertrand conjugation surfaces are parted into three typical types , and the basic equation and differential formula are established , then the conjugation conditions are found . aiming at the inclusive problem , the structure condition is given 论文将白川德共轭按母线为一般平面曲线、圆弧、直线分为三种典型类型，分别建立了共轭的基本方程与微分关系式，据此给出了各种类型的共轭基本条件，发现这是一类更强更严的条件，存在有相容问题，进而研究了白川德共轭的结构条件，至此确立了白川德共轭的基本框架。
The contacting measurement method with a double probe is put forward after the detailed analysis of the state - of - the - art measuring methods of the thickness of wall . firstly , the theory - profile generatrix is built , and then the movement curve of the track of joint center is constructed , which aims at making the joint center move along the movement curve and keep the fixed sensor touching the wall . the measuring sensor examines the line in its normal direction of the interior wall all the time , the data from the sensor is the thickness value of the wall 论文通过分析国内外变曲率回转体壁厚测量的现状,提出了双测头接触式测量方案:通过构造理论轮廓母线,建立铰链中心的运动曲线,使铰链中心始终沿运动曲线运动,以保证固定触头与传感器测头的连线始终在内壁法线方向上,从而传感器测头所得的数值即为壁厚值,该方案经模拟测试实验取得了预期效果。
Base on the study and practice about fast protecting project of jkm - 1 type generatrix , indicator system is build about scientific project and engineering project of electric company . after show the overall process of project post evaluation , it provides some suggestions and countermeasures concerning the scientific project and project post evaluation in our country ’ s actual condition . the article gathers the experiences for the development of project post evaluation and provides some reference and consultation 本文着眼于对电力行业中的一个典型研发项目进行后评价研究,系统地阐述了项目后评价的理论、方法、指标体系和流程,通过对jkm - 1型10千伏母线保护研发项目后评价全过程的分析和对该项目重点问题的研究,确立了电力行业科技项目和工程项目后评价的指标体系,最后就我国电力行业科技项目和工程项目的管理提出了对策和建议,希望为电力企业项目后评价工作的开展提供参考和借鉴。
