用于三相PWM并网逆变器的改进型幅相控制方法

In this paper, a vector regulating principle of the phase and amplitude control （ PAC ） method for three-phase grid-connected inverters is presented. To solve the problem of heavy inrush current and slow dynamic response when system starts up, the starting voltage prediction control and the current feed-forward control are proposed and used, which improve the dynamic performance of the system in the PAC. The experimental results carried out on a three-phase grid-connected inverter proved the validity of the proposed method.     

Implementation of a new PC based controller for a PUMA robot

This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct control of six joints. The original structure of the PUMA robot is retained. The hardware of the new controller includes such in-house designed parts as pulse width modulation (PWM) amplifiers, digital and analog controllers, I/O cards, signal conditioner cards, and 16-bit A/D and D/A boards. An Intel Pentium IV industrial computer is used as the central controller. The control software is implemented using VC programming language. The trajectory tracking performance of all six joints is tested at varying velocities. Experimental results show that it is feasible to implement the suggested open architecture platform for PUMA 500 series robots through the software routines running on a PC. By assembling controller from off-the-shell hardware and software components, the benefits of reduced and improved robustness have been realized.     

基于Profibus_DP总线的发动机动力性能分布式测控系统

提出了一种发动机动力性能分布式测控系统,介绍了Profibus_DP总线的通信协议及系统的网络结构,主要参数的测量原理,并详细讨论了由工控机、图形操作终端、变频器及可编程控制器组成的测控系统的结构及工作原理,系统的软硬件设计方法.实际应用表明,系统组态灵活、编程方便、可靠性高.     

基于TMS320LF2407带材自动对中控制系统设计

为解决传统对中系统检测精度不高、运行速度慢、扩展功能少、实时性不强的缺点,设计了以CCD为检测传感器、TMS320LF2407芯片为控制核心的对中系统,提高了系统的检测精度,增强了系统的稳定性和实时性,并提供了更多的外部接口使系统易于扩展。本系统已应用于实际中,效果良好。     

Mixed nonlinear dynamic voltage phasor tracing method based on WAMS/SCADA

By considering the static voltage characteristic of the load, we propose a WAMS/SCADA mixed nonlinear method to estimate the voltage of unobservable buses caused by topology change or phasor measurement unit （PMU） malfunction in a power system. By modeling the load characteristic with data from SCADA, we employed the Gauss-Seidel method to solve the nonlinear equations and estimate the voltage of unobservable buses with the high precision voltages of neighboring buses measured by a PMU. Simulations were carried out on the IEEE 39-bus system, and the results show that this novel method can dynamically and accurately trace the variation of the voltage phasor of the unobservable buses.     

PMAC罗茨鼓风机扭叶转子加工数控系统研究

为实现罗茨鼓风机扭叶转子的专用数控加工,根据三叶扭叶转子的曲面特征,设计了一种新颖的数控铣削的方法,研制了基于PMAC的罗茨鼓风机扭叶转子加工试验台专用数控系统。系统上层控制软件采用模块化设计,并利用V isual Basic6.0开发了相应的人机界面和管理应用功能模块。调试的结果表明,系统软件运行稳定,实现了对了扭叶转子的铣削数控加工。     

面向一流人才培养的研究生教育质量评价方法初探--基于层次分析与模糊综合评判的指标体系研究

研究生教育在"双一流"建设中具有高端引领和战略支撑作用。要提升研究生教育质量,必须加强研究生培养质量保障体系建设,而构建研究生教育质量评价体系是其重要一环。为此,本文提出研究生教育质量评价的基本原则和价值取向,并据此研究设计涵盖学生发展、师资队伍、学校条件以及利益相关方满意度等4项一级指标、13项二级指标和91项三级指标的研究生教育质量综合评价方案。在此基础上,运用专家调查法对91项三级指标重要度进行0~5级综合评价,采用层次分析法对三级指标的权重进行科学赋权。同时,采用模糊综合评价方法对13项二级指标与4项一级指标进行权重分析与判断,进而给出一套完整的研究生教育质量综合评价指标体系,为科学评价面向一流人才培养的研究生教育质量提供参考和借鉴。