ASME规范钢印产品的质量控制

美国ASME B＆PV规范是被世界公认的技术内容最为完整、应用最为广泛的锅炉及压力容器标准。文章论述了按照ASME规范第1卷、第Ⅷ卷第1分册建立起来的ASME质量控制体系在ASME规范钢印产品（文中简称“ASME规范产品”）设计、制造及检验等过程中的运用。     

ASME规范标志的要求

锅炉制造企业必须严格地执行ASME规范。ASME规范中关于锅炉规范标志(包括标志内容、标志位置等)的要求。     

ASME 核证的取证过程

随着国内核电事业的蓬勃发展,越来越多的国内核电设备制造厂开始着手进行ASME核证的取证工作。本文简要介绍了ASME核证的范围和取证过程,供有关企业和相关技术人员参考。     

ASME规范材料的应用及其国产化问题

ＡＳＭＥ规范产品在我厂已占主导地位，在制造中大量使用ＡＳＭＥ规范材料，本文针对ＡＳＭＥ规范材料应用概况、标准特点及其国产化等方面进行论述，对我厂使用ＡＳＭＥ规范材料进行较系统的总结。     

基于ASME规范的NDE国际接轨

就ASME规范现行版（2004＋2006增补）有关承压设备无损检测（NDE）的基本规定，对照中国相关标准，并结合国内工厂企业生产实际，指出日常NDE操作中的一些禁忌、误区和注意点，意在为NDE国际接轨献一孔之见。     

ASME核规范标记的要求

为了迎接我国第三代核技术的引进,适应国际市场竞争的要求,有能力的核设备建造企业持有ASME核设备授权证书和钢印势在必行。本文较为详细地介绍了ASME核规范中关于物项(包括设备、零件、附件、管道分组件、堆芯支撑等)的规范标记的要求。     

锅炉制造检验国内行业标准和ASME规范的差异

现在随着中国锅炉制造业水平的快速发展,大量国外锅炉加工订单涌向中国企业,其中较多一部分均为按美国ASME规范制造的锅炉产品。但是,纵观中国标准和ASME规范这两种标准体系,其中对受压部件制造过程的产品试板（试样）及无损探伤控制是有明显差异的。从这两种标准体系的对比中,我们可发现他们不同的控制要求。     

ASME法规产品的材料管理

ASME法规产品在材料管理方面的有关规定,着重阐述了材料在验收、保管、发放和使用时的各项规定。     

ASME规范铁基铸件的现状

我国加入WTO以后,有些企业已按ASME法规(或规范)要求,生产铁基铸件。为了更好的了解ASME法规中铁基铸件的现状,介绍了ASME法规2002年7月1日增补版对铁基铸件的基本要求,ASME与ASTM的关系,ASME铁基铸件的特点等。     

ASME PTC 4-1998锅炉性能试验规程的主要特点

介绍和分析了美国机械工程师协会(ASME)颁布的新版锅炉性能试验规程ASME PTC 4-1998的主要特点,讨论了新增补的内容,重点分析了与ASME PTC 4.1-1964年版本及我国国标<电站锅炉性能试验规程>(GB 10184-1988)的若干重要区别.对我国火力发电行业锅炉机组的设计、制造、运行、调试的工程技术人员更好地使用ASME PTC 4-1998具有一定参考价值.     

Allowable local thickness of wall-thinned straight pipes in ASME Code Case N-597-2

The wall-thinning problem has become a hot issue in the assessment of the structural integrity of pipes and pipe items. A criterion is necessary to determine the possibility of continuing use for the wall-thinned pipes detected by non-destructive inspection. The American Society of Mechanical Engineers (ASME) Boiler & Pressure (B&PV) Vessel Section XI, Div. 1, Code Case N-597-2 [Requirements for analytical evaluation of pipe wall thinning, 2003] provides the criterion. But the code case has several limitations and difficulties for application and sometimes gives non-consistent allowable local thickness values. So works are in progress to modify and extend the code. For that purpose, it is also necessary to understand fully the technical bases of the code case.     

摩托车电喷系统的电控单元及其控制策略

介绍电喷系统电控单元的功能和基本控制原理，以及相关数据类型；以基于infineonXC164CM单片机研发的摩托车电控单元为例介绍电控单元的硬件特点，软件特点及其控制策略。     

SMC-DPC based active and reactive power control of grid-tied three phase inverter for PV systems

In this paper, sliding mode control (SMC) – direct power controller (DPC) based active and reactive power controller for three-phase grid-tied photovoltaic (PV) system is proposed. The proposed system consists of two main controllers: the DC/DC boost converter to track the possible maximum power from the PV panels and the grid-tied three-phase inverter. The Perturb and Observe (P&O) algorithm is used to transfer the maximum power from the PV panels. Control of the active and reactive powers is performed using the SMC-DPC strategy without any rotating coordinate transformations or phase angle tracking of the grid voltage. In addition, extra current control cycles are not used to simplify the system design and to increase transient performance. The fixed switching frequency is obtained by using space vector modulation (SVM). The proposed system provides very good results both in transient and steady states with the simple algorithms of P&O and SMC-DPC methods. Moreover, the results are evaluated by comparing the SMC-DPC method developed for MPPT and the traditional PI control method. The proposed controller method is achieved with TMS320F28335 DSP processor and the system is experimentally tested for 12 kW PV generation systems.     

A novel method for obtaining virtual inertial response of DFIG‐based wind turbines

This paper investigates virtual inertia control of doubly fed induction generator (DFIG)‐based wind turbines to provide dynamic frequency support in the event of sudden power change. The relationships among DFIGs' virtual inertia, rotor speed and network frequency variation are analysed, and a novel virtual inertia control strategy is proposed. The proposed control strategy shifts the maximum power point tracking (MPPT) curve to the virtual inertia control curves according to the frequency deviation so as to release the ‘hidden’ kinetic energy and provide dynamic frequency support to the grid. The calculation of the virtual inertia and its control curves are also presented. Compared with a PD regulator‐based inertial controller, the proposed virtual inertia control scheme not only provides fast inertial response in the event of sudden power change but also achieves a smoother recovery to the MPPT operation. A four‐machine system with 30% of wind penetration is simulated to validate the proposed control strategy. Simulation results show that DFIG‐based wind farms can provide rapid response to the frequency deviation using the proposed control strategy. Therefore, the dynamic frequency response of the power grid with high wind power penetration can be significantly improved. Copyright © 2015 John Wiley & Sons, Ltd.     

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Due to the high interest in renewable energy and diversity of research regarding photovoltaic (PV) array, a great research effort is focusing nowadays on solar power generation and its performance improvement under various weather conditions. In this paper, an integrated framework was proposed, which achieved both maximum power point tracking (MPPT) and minimum ripple signals. The proposed control scheme was based on extremum-seeking (ES) combined with fractional order systems (FOS). This auto-tuning strategy was developed to maximize the PV panel output power through the regulation of the voltage input to the DC/DC converter in order to lead the PV system steady-state to a stable oscillation behavior around the maximum power point (MPP). It is shown that fractional order operators can improve the plant dynamics with respect to time response and disturbance rejection. The effectiveness of the proposed controller scheme is illustrated with simulations using measured solar radiation data.