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.     

Grid-connected inverter for wind power generation system

In wind power generation system the grid-connected inverter is an important section for energy conversion and transmission, of which the performance has a direct influence on the entire wind power generation system. The mathematical model of the grid-connected inverter is deduced firstly. Then, the space vector pulse width modulation (SVPWM) is analyzed. The power factor can be controlled close to unity, leading or lagging, which is realized based on PI-type current controller and grid voltage vector-oriented control. The control strategy is verified by the simulation and experimental results with a good sinusoidal current, a small harmonic component and a fast dynamic response.     

Integration and verification case of IP-core based system on chip design

In this paper, the design and verification process of an automobile-engine-fan control system on chip （SoC） are introduced. The SoC system, SHU-MV08, reuses four new intellectual property （IP） cores and the design flow is accomplished with 0.35 btm chartered CMOS technology. Some special functions of IP cores, the detailed integration scheme of four IP cores, and the verification method of the entire SoC are presented. To settle the verification problems brought by analog IP cores, NanoSim based chip-level mixed-signal verification method is introduced. The verification time is greatly reduced and the first tape-out achieves success which proves the validity of our design.     

基于预测控制的直接转矩控制系统的研究

针对异步电动机直接转矩控制（DTC）系统在低速时由于开关频率不稳定而引起转矩脉动较大的缺点，提出了一种预测控制方法。该方法根据转矩和定子磁链的误差来确定应该施加的参考电压矢量，最后利用空间矢量脉宽调制（SVPWM）方法来合成该矢量，这样即保证了逆变器的开关频率恒定，从而大大降低转矩脉动。仿真结果表明，在低速下定子磁链轨迹近似为圆，转矩脉动不明显。     

直驱永磁风电机组低电压穿越的一种控制策略

为提高并网直驱永磁风电机组低电压穿越运行能力,提出一种适用于双PWM变换器并网的永磁直驱风电机组低电压穿越运行的电机侧及电网侧变换器协调控制策略。电网电压跌落时,根据输入电网的电磁功率的变化控制电机侧变换器来限制发电机的电磁功率以平衡输入直流侧电容的功率,稳定直流侧电压;根据电网电压跌落深度控制电网侧变换器,提供一定的无功电流,有利于电网电压稳定与恢复,提高风电机组的低电压穿越能力。仿真结果表明,所提控制方案无需硬件装置,能有效实现永磁直驱风电机组的低电压穿越运行。     

用于高压电子式电流互感器的能力和数据复合光纤传输系统

This paper describes a prototype power delivery system developed for high voltage electronic current transformer (ECT) that uses laser light to transfer power to and communicates with the primary converter. The design is based on optical-to-electrical power converters, solid-state diode lasers and optical fibers. Command signals are transmitted via the same up-fiber used to send power from secondary power supply to primary converter. The upward data transmission is completed during the brief interruption of power delivery without affecting steady power-supply. A simple comparator added to the primary converter can take the command data. Experimental results show that the fibers can provide reliable up-link for data transmission at 200 kb/s from the secondary to the primary converter. Based on the delivery system, the secondary converter can control three auxiliary channels to provide additional information. These monitoring channels are used in a time-multiplexing mode to provide information about the operation temperature, voltage and current at the remote unit for monitoring the ECT. This preventive maintenance or built-in test can increase reliability by giving early warning for necessary maintenance request.     

基于自适应预测算法的APF无差拍控制方法

有源电力滤波器（active power filter, APF）补偿电流跟踪控制要求具有较高的稳态精度和较快的动态响应速度。文章将自适应预测滤波算法应用于无差拍控制,实现APF补偿电流精确控制。根据APF时域数学模型,推导滤波系统的无差拍控制离散方程;通过自适应(finite impulse response filter, FIR)预测滤波算法实现基波电流预测,消除控制系统的计算延迟,给无差拍控制提供所需的指令电流预测值。对预测算法进行MATLAB仿真,验证预测算法的稳态精度和动态跟踪快速性;实验室样机验证控制实验结果证明所提出的控制策略有效的,具有一定的实用性。     

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.     

混联式混合动力客车逻辑控制策略研究

混合动力客车的控制策略决定整车的性能。分析某混联式混合动力客车的组成结构和基于逻辑控制的控制策略,建立相应的混联式混合动力客车仿真模型及其控制器,通过AVL/CRUISE和MATLAB/Simulink联合仿真分析,获得该车在中国典型城市公交工况下的动力性和百公里油耗。仿真结果表明,各主要部件能按照控制规则实现状态的合理切换,基于逻辑控制的控制策略能满足整车性能指标要求。     

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.     

TDD-CDMA 系统中基于业务统计的联合功率控制算法

An important feature of the traffic in mobile networks is burstiness. Drawbacks of conventional power control algorithms for time division duplex （TDD）-code division multiple access （CDMA） systems are analyzed. A joint power control algorithm based on service factor is presented to address the TDD-CDMA mobile services in the burst mode according to the Markov modulated Bernoulli process. The joint power control equation is derived. A function model is developed to verify the new algorithm and evaluate its performance. Simulation results show that the new power control algorithm can estimate interference strength more precisely, speed up convergence of power control, and enhance power efficiency and system capacity. It is shown that the proposed algorithm is more robust against link gain changes, and outperforms the reference algorithms.     

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。     

Nonlinear model predictive control with guaraneed stability based on pesudolinear neural networks

A nonlinear model predictive control problem based on pseudo-linear neural network (PNN) is discussed, in which the second order on-line optimization method is adopted. The recursive computation of Jacobian matrix is investigated. The stability of the closed loop model predictive control system is analyzed based on Lyapunov theory to obtain the sufficient condition for the asymptotical stability of the neural predictive control system. A simulation was carried out for an exothermic first-order reaction in a continuous stirred tank reactor. It is demonstrated that the proposed control strategy is applicable to some of nonlinear systems.     

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。