微型光伏并网逆变器的设计

微型并网逆变器作为屋顶光伏系统的核心,使用越来越广泛。论述了微型并网逆变器的方案设计、电路设计,简单介绍了基于数字信号处理芯片TMS320F2812的控制原理,分析了最大功率点跟踪和反孤岛效应。试验结果表明微型逆变器输出并网电流波形良好,与电网电压同频同相。     

基于DSP控制的单相光伏并网逆变系统的设计

阐述了基于数字信号处理器TMS320F2812控制的单相光伏并网逆变系统的设计,该系统主要应用于小功率光伏并网发电系统。分析了系统的结构和控制原理,设计了最大功率跟踪MPPT(Maximum power point tracking)算法和锁相环的软件设计流程图,构建了实验室样机。实验结果表明并网电流波形良好,但含有少量的高次谐波,逆变器输出的电流基本与电网电压同频同相,并网的功率因数近似为1。     

基于DSP控制的单相光伏并网逆变系统的设计

阐述了基于数字信号处理器TMS320F2812控制的单相光伏并网逆变系统的设计,该系统主要应用于小功率光伏并网发电系统.分析了系统的结构和控制原理,设计了最大功率跟踪MPPT(Maximum power point tracking)算法和锁相环的软件设计流程图,构建了实验室样机.实验结果表明并网电流波形良好,但含有少量的高次谐波,逆变器输出的电流基本与电网电压同频同相,并网的功率因数近似为1.     

基于TMS320F2808直接转矩控制系统的硬件设计实现

本文采用TMS320F2808芯片作为控制核心,完成了一个全数字化直接转矩控制硬件系统,克服了采用TMS320F2407A和TMS320F2812DSP作为直接转矩控制系统的处理器所存在的缺点,给出了电流、电压检测电路。实验结果表明,该系统作为无速度传感器直接转矩控制策略的硬件平台,具有抗干扰能力强,电流电压保护措施良好,体积小,软件可移植性强等特点。     

单相光伏并网逆变器控制系统的研究

基于TMS320F2812型DSP芯片设计了一套10 kW单相光伏并网逆变器.阐述了单相光伏并网逆变器的主回路组成以及控制系统的设计.采用了适当的算法确保逆变器输出的功率因数接近于1,谐波含量低.该系统具有最大功率跟踪和反孤岛效应等功能,现场运行结果表明了所提出的控制方案具有良好的性能.     

基于TMS320F2812的数字化三相变频电源的研制

介绍了基于DSP TMS320F2812的三相正弦波变频电源系统,详细的分析以及设计了主回路、控制回路的软件和硬件部分,并且对控制策略、电源系统控制的三种工作模式进行了探讨,讨论了利用TMS320F2812产生频率和幅值可按需要改变的SPWM波的程序设计策略和算法,扩展TMS320F2812的随机存储器,通过SPLC501液晶显示器实时显示线电压、线电流的有效值以及正弦波的频率。实验效果良好,满足了变频电源系统设计的各项要求。     

基于TMS320F2812处理器的移相全桥开关的设计

对定点32位数字信号处理器TMS320F2812的EV模块进行研究,给出了移相全桥控制方式主电路和工作波形,介绍了基于TMS320F2812的移相全桥软开关的设计与实现方法。该方法已经在一个高频功率逆变的工程应用中被证明可行,应用效果良好。     

基于DSP的单相光伏并网控制系统的设计

提出一种基于改进型重复控制和传统PI控制的光伏并网复合控制策略,重复控制器用来减小并网电流的稳态误差,传统PI控制用米提高系统的动态性能.为验证提出的算法,搭建了基于TMS320F2812的单相光伏并网逆变系统实验模型.实验结果表明.提出的算法能够减少并网电流谐波,同时系统兼顾了良好的动静态性能.     

基于TMS320LF2407的光伏并网逆变器的研究

在介绍光伏并网逆变器的基本原理和拓扑结构基础上，提出基于TMS320F2407型DSP的单相电压源输入、电流输出控制方式的并网逆变器设计方案。采用电导增量法跟踪控制太阳电池的最大功率点，利用TMS320F2407芯片产生相应的SPWM波控制功率器件的导通与关断，使用零电流跟踪误差控制实现并网电流无静差的跟踪电网电压，最终实现了快速稳定追踪太阳电池最大功率，并以与电网电压同频、同相正弦电流波形送入电网，提高了系统逆变效率和可靠性。     

基于TMS 320F2812的矢量控制系统的研究

以DSP TMS 320F2812为控制核心,设计性能良好的交流调速系统,给出了系统设计方案。在详细分析矢量控制算法的基础上,介绍了系统软件设计,并给出了软件流程图。     

Simulation Study on On-Line MTPA/MTPV Trajectory Tracking in PMSMs with Power Management

Abstract

This paper proposes an on-line maximum torque per ampere (MTPA)/maximum torque per voltage (MTPV) trajectory tracking method in permanent magnet synchronous machines (PMSMs) with power management. The on-line MTPA/MTPV machine current trajectory tracking algorithm is developed from PMSM model. Maximum source current and machine current are regulated to enhance hardware protection during machine current trajectory tracking. The maximum source current management is achieved by iterating within the current trajectory tracking algorithm over continuous torque command modifications based on power flow analysis, and the maximum machine current management is achieved by torque command limiting based on current angle modulation. Different from the existing techniques in literature, the proposed method has an unique feature of providing on-line regulation of source current, while maintaining on-line MTPA/MTPV trajectory tracking in PMSMs. It also provides machine and inverter overcurrent regulation to enhance their protection. In addition, the proposed method is flexible to tune and does not require off-line calibration. The effectiveness of the proposed method is confirmed by simulation results in MATLAB.     

Current Tracking Error Analysis for Shunt Active Power Filters

Direct current control has been used in many voltage source converters connected to the grid, such as shunt active power filters. In their stationary coordinates control systems, there are two closed control loops, one is the current loop and the other is the voltage loop. In practical applications, because the voltage source converters are connected to the grid, the output current will be affected, a quite significant tracking error exists in the current control loop while the actual output current of the converter is still satisfactory. Analyses and design considerations are carried out to investigate this confusing issue. The tracking error is caused by the source voltage; it is an active current and does not affect the compensation results of reactive and harmonic current. The variables that affect the current tracking error are identified, then the influence of tracking error is proposed to guide practical applications. Experimental results verify the analyses and design considerations.     

Error tracking mode AC current waveform control method for three-phase self-commutated voltage source power converters

A novel design theory for a three-phase self-commutated power conversion system (PCS) to perform as an ac current source is proposed. In this new ac current waveform control method termed error tracking mode, the switching instructions of main devices are decided only by the error function of ac current at every data sampling time that comes in a constant period. The performance is theoretically evaluated. Simulation by SPICE also is executed and the characteristics are inspected. Error tracking mode has the following attractive features. It can treat two arbitrary current waveforms as target functions of two-phase arbitrary ac currents. The error between actual ac current value and the objective function value can be controlled and guaranteed to be less than an arbitrary value, which is given beforehand. All control components can be digitized. The minimum continuous on and off time of main devices is guaranteed in advance. No special starting control is necessary because actual ac currents are guaranteed to start tracking the target functions automatically. Error tracking mode makes contributions to improve precision in current control and to reduce current harmonics of self-commutated voltage source power converters.     

Analysis of Surface Degradation of Silicone Rubber Insulation Due to Tracking Under Different Voltage Profiles

Tracking is basically a carbonaceous process. In the present study, the tracking phenomenon in silicone rubber material has been studied under AC and DC voltage. The influence of applied voltage magnitude, conductivity, and flow rate of the contaminant on tracking, were analyzed. It is observed that the tracking is more severe under DC voltages. The tracking time is less under negative DC voltage compared to the positive DC voltage. The tracking mechanism is explained in detail. The leakage current during the tracking studies was measured and its trends were analyzed by using the moving average technique. The leakage current magnitude is high with thermally aged specimens when compared to the virgin specimen, irrespective of the type of applied voltage. It is realized that the tracking time and the leakage current magnitude shows an inverse relationship. In addition, the surface condition of the insulation material was analyzed with the water aged specimen and the diffusion coefficient of the material was calculated. The reduction in contact angle of the specimen has direct impact in the reduction of its tracking time. The tensile test and DMA test results indicate that thermal aging of the specimen alter the mechanical properties of the material. The activation energy of the material was calculated through DMA studies, indicating that materials with high activation energy show an increase in tracking time of the specimen.     

复合绝缘子转轮法老化试验系统设计与开发

主要设计开发了一套基于槽轮传动结构的转轮法机械装置和泄漏电流采集测量系统在内的复合绝缘子转轮法老化试验系统,该系统包括槽轮传动机构的转轮试验平台设计、电流传感器和保护电路的设计以及基于LabVIEW8.0软件平台的泄漏电流分析软件的开发,通过选用屏蔽电缆、采取电缆屏蔽层一端接地和加装隔离变压器等措施解决了背景噪声和电磁干扰问题,最后对泄漏电流测量系统的准确度进行了验证,结果表明该系统自动化程度高,机械系统稳定,泄漏电流测量系统准确可靠,有利于复合绝缘子转轮法老化试验的深入研究。     

用于电机传动系统的多逆变器并联控制技术

为了解决用于低压大电流电机传动系统的逆变器并联控制问题,对跟踪参考电流方式的主从式矢量控制系统进行了研究。在建立电机电流和并联逆变器环流等效电路模型的基础上,分析了电机电流和环流的控制原理,提出了跟踪参考电流方式的主从式矢量控制策略,并从电机稳定性能角度研究了电流调节器的设计原则,最后对控制系统性能进行了仿真和实验分析。研究结果表明:该控制策略间接引入了均流环控制,能有效减小并联逆变器之间的环流;通过对电流调节器参数的合理设计,使得电机具有较好的稳定性能和动态性能。     

基于反电流跟踪的低电压穿越控制研究

分析了双馈感应电机(doubly-fed induction generator,DFIG)在电网电压跌落故障工况下的动态特性,推导了定子磁链和转子感应电动势表达式,研究了一种反电流跟踪控制策略。基于定、转子电流变化关系,设计电流跟踪系数,控制转子电流反向追踪定子电流的变化,有效抑制转子过流,实现DFIG低电压穿越(low voltage ride through,LVRT),确保发电系统平稳持续运行。控制手段简易,电流跟踪系数可控,能有效缓和转矩振荡。通过Matlab/Simulink平台进行仿真研究,结果表明了该方法的正确性和有效性。     

太阳能光伏并网发电系统的研究

针对光伏阵列的特点,提出了基于最大功率点跟踪(MPPT)的光伏阵列并网发电方案,采用电网电压前馈和电流跟踪技术,建立了相关的控制模型,实现了网侧电流正弦化且为单位功率因数,实验结果证明了方案的正确性.     

有源滤波器空间矢量脉宽调制电流跟踪算法的优化

为提高有源滤波器的电流跟踪性能,针对传统空间矢量脉宽调制(SVPWM)电流跟踪算法的不足,提出了一种用于并联有源滤波器的SVPWM电流跟踪算法的优化方法。该跟踪算法利用三相相间误差电流的正负来判断空间指令电压矢量所在的区域。与传统SVPWM电流跟踪算法相比,省略了三相电网电压的检测环节,即省略了判断空间指令电压矢量所在区域的复杂运算,从而简化了硬件电路,同时也简化了算法。针对以三相不可控整流阻感负载为谐波源的电路模型,分别采用传统SVPWM电流跟踪算法和所设计的SVPWM电流跟踪算法作为有源滤波器的电流控制方法,进行了滤除谐波电流的实验。     

基于CPA和FSCC的自适应扰动观察法在MPPT中的应用

针对定步长扰动观察法存在的不足,提出一种基于局部短路电流启动的自适应变步长最大功率跟踪方法。该方法将电流扰动(CPA)和局部短路电流(FSCC)结合,利用自适应扰动法调整扰动步长;同时在恒压启动时,引入温度调整系数,计算最大功率点补偿值,从而应对外界环境的迅速变化。文中于MATLAB/simulink建立起80 W光伏发电系统模型,与传统最大功率跟踪方法进行对比实验。实验结果表明:所提出的最大功率跟踪方法使系统具有很好的静、动态性能。