H∞ loop-shaping controller design for a grid-connected single-phase photovoltaic system

This paper presents a H_∞ loop-shaping controller for controlling dc-link voltage by regulating the switching signal of the inverter associated with a grid-connected single-phase photovoltaic system. To facilitate a robust control design, state-space realisation of the system model is made with uncertainties represented by linear fractional transformation. The controller is achieved through H_∞ synthesis followed by obtaining desired loop shapes through the choice of the proper weighting functions. The controller order is reduced by Henkel-norm method for facilitating its practical implementation. Controller performance is evaluated through carrying out simulations on MATLAB/Simulink platform under standard and changing atmospheric conditions, and fault condition.     

Environmental assessment of garden waste management in the Municipality of Aarhus, Denmark

An environmental assessment of six scenarios for handling of garden waste in the Municipality of Aarhus (Denmark) was performed from a life cycle perspective by means of the LCA-model EASEWASTE. In the first (baseline) scenario, the current garden waste management system based on windrow composting was assessed, while in the other five scenarios alternative solutions including incineration and home composting of fractions of the garden waste were evaluated. The environmental profile (normalised to Person Equivalent, PE) of the current garden waste management in Aarhus is in the order of −6 to 8 mPE Mg⁻¹ ww for the non-toxic categories and up to 100 mPE Mg⁻¹ ww for the toxic categories. The potential impacts on non-toxic categories are much smaller than what is found for other fractions of municipal solid waste. Incineration (up to 35% of the garden waste) and home composting (up to 18% of the garden waste) seem from an environmental point of view suitable for diverting waste away from the composting facility in order to increase its capacity. In particular the incineration of woody parts of the garden waste improved the environmental profile of the garden waste management significantly.     

湿法脱硫真空皮带机运行控制分析与改进

介绍了真空皮带机脱水过程的基本原理及其在石灰石—石膏湿法脱硫系统中的应用情况,分析了PID控制真空皮带机运行的原理。由于真空皮带机常规PID控制系统的滞后严重,采用模糊控制后系统的响应得到了较好的改善,实际应用结果证明了理论的正确性。     

侧联式球磨机的噪声控制

介绍了侧联式球磨机噪声产生原理及其噪声控制方法,选择了制作局部式隔声罩的噪声控制设计和装置结构.在中国铝业中州分公司热电厂球磨机上应用,取得了很好的隔声效果.     

连续流分段进水生物脱氮工艺控制要点及优化

主要介绍了分段进水生物脱氮工艺的系统工作原理及工艺特性,并探讨了该工艺运行操作和设计的几个重要影响因素,如进水流量分配比、溶解氧、污泥回流比、C/N比等,并在此基础上讨论了分段进水生物脱氮工艺的优化控制对策.     

常熟河网区水污染物总量控制研究

基于常熟河网原型调水实验和水功能区划，建立了感潮地区河网水量水质模型，对常熟河道水质降解系数及水环境容量进行了计算，并按照点源和面源对区域内污染源进行统计，在此基础上进行了常熟河网水污染物总量控制值和现状削减量的计算，为该地区的水污染防控提供了科学依据。     

A/O脱氮工艺的控制策略和应用性研究

根据A/O脱氮工艺的运行状况和影响因素 ,提出了应用在线传感器连续测定曝气池中DO浓度、氨氮浓度和硝酸氮浓度 ,并据此调节供氧强度、内循环回流量、有机碳源的投加以及硝化区和反硝化区的大小 ,这是保证A/O脱氮工艺良好处理效果的重要控制策略和思想。同时对近年来国外A/O脱氮工艺自动控制的应用及研究进行了简单的回顾。     

高效喷淋泡沫脱硫技术及装置的应用

SO2是产生酸雨的主要气体，其主要来源于工业燃煤锅炉。以沈阳一家电厂为例，该厂选用新型高效的喷淋泡沫脱硫除尘器对锅炉排放的SO2进行治理。进入喷淋泡沫塔前的SO2平均浓度为2780mg／m^3，经脱硫后出塔平均浓度为289．3mg／m^3，去除率为89．6％。结果表明，这种有别于传统湿法的新型高效的喷淋泡沫脱硫技术及装置具有脱硫效率高、装置占地少、运行稳定、沉淀物易于回收利用等特点，对锅炉排放的SO2进行治理是非常有效的。     

中国山东电网燃煤锅炉NOx排放状况和治理技术试验研究

通过对山东电网所属发电厂锅炉NOx排放状况进行调查、测试,得出锅炉NOx排放量与煤种、炉型、燃烧器型式、运行中空气过剩系数、负荷等的关系.结果表明,山东省火力发电厂50 MW及以上容量机组2003年的NOx排放总量超过40万t(按NO2计算).控制和治理NOx排放已成为刻不容缓的重要工作.     

给水厂铁铝泥构建过滤柱去除富营养化河水中过量磷

为避免因FAS释放过量有机物和氮而产生的潜在不利影响,分析了以给水厂铁铝泥(FAS)构建过滤柱处理富营养化河水的特征与机制,研究了以厌氧热处理改性后的FAS作为辅助基质(2%)构建过滤柱。结果表明：在对其他性质无影响的情况下,FAS的添加显著提高了过滤柱对水体中磷的去除率,促使出水磷浓度在整个运行期间小于0.01 mg·L-1;被FAS吸附的磷主要以NaOH提取态、HCl可提取态和残渣态存在。高通量测序分析结果表明,FAS的添加促使过滤柱中富集了Rhodoplanes、Sulfuritalea、Nitrospira、Leucobacter、Geobacter、Dechloromonas等有助于生物地球化学循环和复合污染控制的菌群。FAS作为辅助基质构建过滤柱可有效控制富营养化河水中磷污染。