用于光纤电流传感器SLD光源的温度控制系统

为减小高压电网中光纤电流传感器超辐射发光二极管（super luminescent diode,SLD）光源温度特性对测量准确度的影响,提出了一种模拟温度控制系统对光源温度进行恒温控制。根据设计要求,介绍了各重要环节的设计过程。分析了通过搭建合适的温度采集电桥,可以得到与温度近似成线性关系的输出差分信号。在频域上建立了系统的数学模型,计算了系统的传递函数,得到了比例-积分-微分（proportional-integral-derivative,PID）控制器各参数对时域上输出的影响。在实验室中搭建了用于光纤电流传感器SLD 光源的温控系统,对温控系统进行了定温与温度循环实验,实验结果表明:该控制系统可以实现对温度的实时控制,使光纤电流传感器测量准确度满足0.2 级工业要求。     

硅钼炉温度控制

用于实验室材料样品烧制及性能测试的硅钼炉，是一类大惯性控制对象。作者采用经验规则控制与ＰＩＤ控制相结合的方法，设计了硅钼炉经验规则控制器和ＰＩＤ控制器由硅钼炉温度偏差大小选择不同的控制器，从而实现对硅钼炉温度的有效控制。该控制系统的温度测量误差ｅｍ≤０．１℃，控制稳态误差ｅｓ≤１℃，测试材料样品的时间也大为缩短。     

基于USB通信的SLED自动控温系统

在SLED的温度控制系统中,以计算机设定半导体激光器工作温度,通过USB实现PC机与目标板之间的通信,针对半导体制冷器（TEC）的驱动特性,设计了基于MSP430单片机脉宽调制（PWM）、比例积分微分算法（PID）的自动温度控制单元。系统以CY7C68013为USB通信模块;利用单片机片内的12hit的A／D转换器采集数据;PC端软件以VC＋＋6．0为开发环境完成数据的输出。激光器温度控制精度在±0．02℃以内。     

Improving the Performance of HF Radio Networks in the Presence of Interference through Automatic Link Establishment with Frequency Hopping Technique

In the cement industry, a rotary kiln is a pyro-processing device that is used to measure temperature. Measuring and maintaining a certain range of temperature in the rotary kiln is important to ensure the production of quality clinker granules. The assessment of consuming zone temperature is acquired using radiation pyrometers from the temperature of a hotspot. However, it is a difficult task to measure the burning zone temperature due to the very high temperature developed in the turning furnace sintering process. Existing pyrometer and camera based techniques are not able to provide accurate temperature and temperature variations developed in the burning zone. This research work considers flame image processing using region of interest (ROI), fuzzy logic, and neural networks for efficient temperature measurement. Various temperature measurement and control techniques are utilized in the existing conventional (Prasanna and Bojja in ESCI (helix—the scientific explorer) 4843–4849, 2019) rotary kiln control techniques. In pyrometer-based measurements, the standard of radiation may lead to errors and inaccurate readings. Hence, the consuming zone temperature estimation got from the radiation pyrometer isn't solid and it is hard to get temperature data for a particular location. A colorimetric device-based intelligent control system measures the burning temperature of a specific point, but reading fluctuations are seen because of smoke and dust developed in the combustion process. In ROI based flame image processing, many factors, such as turbulent flame, brightness of flame zone, and dust, affect identifying the boundary for ROI based flame image analysis. In neural network models, variable selection plays a crucial role in designing effective systems with learning capabilities, but it is not an easy task to accomplish without certain rules. Hence, it is highly necessary to develop an improved control system. In view of the issues in variable and feature selection, a few neuro fuzzy systems are adopted in measurement and control. The consuming zone temperature estimation needs a lot of attention due to the very high temperature developed in the rotary kiln sintering process. Existing techniques have to be improved upon using advanced algorithms and intelligent approaches. A sintering state recognition system has been developed with features of flame images and fusion methodologies. In this approach, various flame image features and texture (Ren and Wang in Int J Autom Compu 11(1):72–77, 2014) features are extracted from the burning zone region. Though these methods address a few issues in flame image processing, the acquired image is largely affected by blurring and internal parameters of the sintering process. Charge coupled device (CCD) camera images and videos are applied to many image processing algorithms for better feature extraction and region extraction. The region of interest-based analysis is mainly focused on temperature assessment in this work. Intelligent control techniques are applied to measure the burning zone temperature in a rotary kiln. Fuzzy logic-based inference systems are combined with neural network algorithms in the development of neuro-fuzzy systems. The fuzzy surmising framework in light of mathematical models is the successful manner to anticipate the temperature esteems utilizing power measures. The fire pictures caught by the CCD cameras are handled utilizing fluffy rule-based picture investigation, which estimates temperature from a fire picture by contemplating RGB power planes. The arrangement of result temperature esteems is wanted to be a participation work. The Mamdani fluffy induction model is used to give planning of fluffy fire temperature. Exact temperature planning of fire pictures is performed to control the temperature inside the going stove to make top notch clinker. The fire picture examination is completed in different edges of three unique datasets, and temperature is estimated for various crude supper feed rates and coal feed rates. However there is a slight distinction in the acquired temperature, the general temperature evaluation process doesn't show a huge contrast as per the dataset.

     

用于气体浓度检测的VCSELs温度控制电路设计

在利用可调谐半导体激光器吸收光谱（TDLAS）技术对气体浓度进行检测时,检测系统对激光器的温度稳定性要求较高。提出了一种基于max1978的VCSEL激光器自动温度控制（ATC）方案,建立了热电制冷器（TEC）的数学模型,对TEC的热惯性进行了测试,以热惯性测试结果为基础对比例积分微分控制（PID）电路参数进行了整定,设计出了具有较高控制性能的温度控制电路。电路采用闭环负反馈自动控制方案,采用PID电路产生控制信号,驱动TEC,实现了对VCSEL激光器工作温度的有效控制。实验测试结果表明,电路的温度控制精度达到+0.03℃,较好地实现了激光器工作温度稳定性的控制。     

A global model for rapid thermal processors

A simple model for the components that make up a rapid thermal processing system is given. These components are the furnace, the pyrometer used to measure temperature, and the control system that utilizes the pyrometer measurement to control the power to the lamps. The models for each of the components are integrated in a numerical code to give a computer simulation of the complete furnace operation. The simulation can be used to investigate the interaction of the furnace, temperature-sensing technique, and the control system. Therefore, the interplay of heat transfer (furnace) properties, optical (pyrometer) parameters, and control gains can be studied. The objective is to define variability in wafer temperature as process parameters change. The following three applications of the model are included: (1) a simulation of open-loop operation; (2) a simulation of the ramp up and subsequent operation with a step change in wafer optical properties; and (3) a simulation of the rapid thermal chemical vapor deposition of polysilicon on silicon oxide which demonstrates the applicability model for actual processes. A technique for correction of pyrometer output to improve temperature control is also presented     

Decentralized control of wafer temperature for multizone rapidthermal processing systems

Decentralized control is shown through analysis and experimentation to be an appropriate strategy for wafer temperature control in certain multizone rapid thermal processing (RTP) systems. An input-output controllability analysis is conducted to illustrate that the direction associated with the reference command (set-point) corresponding to a spatially uniform temperature trajectory specification is nearly in alignment with the “most” controllable direction associated with the maximum singular value for a multiple concentric lamp configuration. Consequently, the control structure need not alter the directionality of the plant and, thus, can be achieved by a simple decentralized controller where the lamps are paired individually to sensors to achieve a multiloop structure where all interactions are not taken explicitly into account. This result is shown to produce acceptable performance even for an ill-conditioned plant since the directions corresponding to the smaller singular values are irrelevant to the uniform temperature control criteria. Moreover, straightforward nonmodel-based tuning of the controller is enabled due to the simplicity of the decentralized control structure     

Recent developments in rapid thermal processing

Rapid thermal annealing (RTA) with a short dwell time at maximum temperature is used with ion implantation to form shallow junctions and polycrystalline-Si gate electrodes in complementary, metal-oxide semiconductor (CMOS) Si processing. Wafers are heated by electric lamps or steady heat sources with rapid wafer transfer. Advanced methods use “spike anneals,” wherein high-temperature ramp rates are used for both heating and cooling while also minimizing the dwell time at peak temperature to nominally zero. The fast thermal cycles are required to reduce the undesirable effects of transient-enhanced diffusion (TED) and thermal deactivation of the dopants. Because junction profiles are sensitive to annealing temperature, the challenge in spike annealing is to maintain temperature uniformity across the wafer and repeatability from wafer to wafer. Multiple lamp systems use arrayed temperature sensors for individual control zones. Other methods rely on process chambers that are designed for uniform wafer heating. Generally, sophisticated techniques for accurate temperature measurement and control by emissivity-compensated infrared pyrometry are required because processed Si wafers exhibit appreciable variation in emissivity.     

一种基于空间光机热模型的自适应PID控制方法

为提高空间相机的控温稳定度以保证成像质量,本文提出一种基于空间光机热模型的自适应比例积分微分（proportional-integral-derivative, PID）控制方法。该控制器的设计从空间光机的热平衡方程出发,能够实时根据光机及与其辐射换热对象的温度修正光机的热模型,继而采用极点配置的方法实时校正PID控制器参数,最终确定本控温周期的加热占空比。本文通过建立抽象的空间光机热模型,分别施加上述自适应PID控制方法与固定参数PID控制方法,对控温效果进行了仿真及实验对比。结果表明,对环境扰动引起的温度波动,该自适应PID控制器始终保持最佳动态响应,控温稳定度优于± 0.1 K,具有更好的控温稳定性和环境适应性。     

A Recurrent Fuzzy-Network-Based Inverse Modeling Method for a Temperature System Control

Temperature control by a Takagi-Sugeno-Kang (TSK)-type recurrent fuzzy network (TRFN) designed by modeling plant inverse is proposed in this paper. TRFN is a recurrent fuzzy network developed from a series of TSK-type fuzzy if--then rules, and is characterized by structure and parameter learning. In parameter learning, two types of learning algorithms, the Kalman filter and the gradient descent learning algorithms, are applied to consequent parameters depending on the learning situation. The TRFN has the following advantages when applied to temperature control problems: 1) high learning ability, which considerably reduces the controller training time; 2) no a priori knowledge of the plant order is required, which eases the design process; 3) good and robust control performance; 4) online learning ability, i.e., the TRFN can adapt itself to unpredictable plant changes. The TRFN-based direct inverse control configuration is applied to a real water bath temperature control plant, where various control conditions are experimented. The same experiments are also performed by proportional-integral (PI), fuzzy, and neural network controllers. From comparisons, the aforementioned advantages of a TRFN have been verified     

用于SERF原子磁力仪的DFB激光器温度控制系统

由于分布反馈式（DFB）激光器的工作温度会影响其激射波长,降低无自旋交换弛豫（SERF）原子磁力仪的磁场测量灵敏度,以TMS320LF2812为核心控制器,采用数字比例-积分-微分（PID）控制技术,设计并研制了一种高精度、高稳定性DFB激光器温度控制系统。在硬件电路设计方面,由温度控制前向通路和温度采集后向通路组成,构成完整的闭环温度控制结构。软件设计中,采用Ziegler-Nichols工程整定方法,实现对P、I和D三个参数的整定。以中心波长为852 nm的DFB激光器为被控对象,利用该温度控制系统对其进行了温度控制实验。实验结果表明:系统的有效控温范围为5～60℃,控温精度为0.02℃,稳定时间为20 s。并且在长时间（220 min）测试中,DFB激光器工作温度稳定性优于7.910-4（RMS）,为其在SERF原子磁力仪的实用化方面提供了性能保障。     

用于微流控荧光PCR的高分辨率温度控制系统

微流控荧光PCR产物在高分辨率熔解（HRM）曲线分析的过程中,随着DNA的解链荧光强度发生突变,而能否检测到该突变点则依赖于温控的精度。提出了多阈值PID算法,设计了一种适用于高分辨率熔解曲线分析的FPGA温度控制系统。根据测得温度值与设定值之间的差异,改变FPGA电路系统输出的脉冲宽度调制(pulse width modulation, PWM)波占空比和算法的调节频率实现对温度的准确控制。经过温度标定后,系统温度控制精度优于0.1℃,分辨率达到±0.01℃。HRM分析实验结果表明,本方法成功地辨别出了DNA序列的单碱基差异,温度控制系统达到了设计的要求。     

A near-infrared methane detection system using a 1.654 µm wavelength-modulated diode laser

By adopting a distributed feedback laser (DFBL) centered at 1.654 µm, a near-infrared (NIR) methane (CH4) detection system based on tunable diode laser absorption spectroscopy (TDLAS) is experimentally demonstrated. A laser temperature control as well as wavelength modulation module is developed to control the laser’s operation temperature. The laser’s temperature fluctuation can be limited within the range of ?0.02—0.02 °C, and the laser’s emitting wavelength varies linearly with the temperature and injection current. An open reflective gas sensing probe is realized to double the absorption optical path length from 0.2 m to 0.4 m. Within the detection range of 0—0.01, gas detection experiments were conducted to derive the relation between harmonic amplitude and gas concentration. Based on the Allan deviation at an integral time of 1 s, the limit of detection (LoD) is decided to be 2.952×10-5 with a path length of 0.4 m, indicating a minimum detectable column density of ~1.2×10-5 m. Compared with our previously reported NIR CH4 detection system, this system exhibits some improvement in both optical and electrical structures, including the analogue temperature controller with less software consumption, simple and reliable open reflective sensing probe.     

Initial nanoheteroepitaxial growth of GaAs on Si(100) by OMVPE

Initial growth studies of GaAs on an array of Si islands nanostructured on (100) oriented silicon-on-insulator substrates show that growth occurs through a mixture of selective-area and 3D growth modes. An optimum initiation growth temperature must tune the growth conditions to the geometry of the seed array so that selective-area control is maintained while defect density is minimized. The optimum temperature for a square array of Si islands, 500 nm in pitch, and 100 nm to 280 nm in diameter, is ∼600 C. This temperature yields single-crystal nucleation on each Si island while maintaining selective-area growth mode control. Transmission electron microscope (TEM) analysis of optimized and non-optimized grown GaAs/Si heterostructures show that they accommodate 0.4–0.7% strain. Further reduction in stacking-fault defects attributed to side wall growth may be possible through masking of side wall or annealing.     

Intermetallic Compound Formation Mechanisms for Cu-Sn Solid–Liquid Interdiffusion Bonding

Cu-Sn solid?Cliquid interdiffusion (SLID) bonding is an evolving technique for wafer-level packaging which features robust, fine pitch and high temperature tolerance. The mechanisms of Cu-Sn SLID bonding for wafer-level bonding and three-dimensional (3-D) packaging applications have been studied by analyzing the microstructure evolution of Cu-Sn intermetallic compounds (IMCs) at elevated temperature up to 400°C. The bonding time required to achieve a single IMC phase (Cu₃Sn) in the final interconnects was estimated according to the parabolic growth law with consideration of defect-induced deviation. The effect of predominantly Cu metal grain size on the Cu-Sn interdiffusion rate is discussed. The temperature versus time profile (ramp rate) is critical to control the morphology of scallops in the IMC. A low temperature ramp rate before reaching the bonding temperature is believed to be favorable in a SLID wafer-level bonding process.     

Tin oxide gas sensor fabricated using CMOS micro-hotplates andin-situ processing

A monolithic tin oxide (SnO₂) gas sensor realized by commercial CMOS foundry fabrication (MOSIS) and postfabrication processing techniques is reported. The device is composed of a sensing film that is sputter-deposited on a silicon micromachined hotplate. The fabrication technique requires no masking and utilizes in situ process control and monitoring of film resistivity during film growth. Microhotplate temperature is controlled from ambient to 500°C with a thermal efficiency of 8°C/mW and thermal response time of 0.6 ms. Gas sensor responses of pure SnO₂ films to H₂ and O₂ with an operating temperature of 350°C are reported. The fabrication methodology allows integration of an array of gas sensors of various films with separate temperature control for each element in the array, and circuits for a low-cost CMOS-based gas sensor system     

On-situ monitoring of sleet-thawing for OPGW based on long distance BOTDR

With the absence of on-situ temperature monitoring of optical fiber composite overhead ground wire (OPGW) for the process of sleet-thawing, early temperature warning and safety control of direct current (DC) in sleet-thawing process is difficult. Here we propose a Brillouin optical time-domain reflectometry (BOTDR) with broadband receiving for fast measurement and with distributed Raman amplification for long distance measurement of about 100 km. A field experiment for on-situ temperature monitoring of sleet-thawing of OPGW is also reported, which shows uneven change of temperature along the OPGW. The difference between the maximum and the minimum temperature change can be greater than 40 °C.     

Sensorless temperature estimation and control of shape memory alloy actuators using thermoelectric devices

A method for feedback control of the temperature of shape memory alloy (SMA) actuators without using dedicated temperature sensors is presented in this paper. Thermoelectric devices (TEDs) are used to simultaneously sense and control the SMA temperature by alternating between driving the TEDs via the Peltier effect and measuring the local temperature difference across the TEDs via the Seebeck effect. A low-order ARX model that estimates the SMA temperature is derived. This model is used for feedback control of the SMA temperature in lieu of an external temperature sensor. A controller is implemented, which demonstrates the performance of the estimation technique. This method will enable the production of large arrays of TED-driven SMA tendon actuators, particularly for large DOF robotic systems.     

面向航空发动机热源模拟台的多路温度调控系统设计

针对某型航空发动机热源模拟台的温度调控需求,设计一种以STM32低功耗微处理器为控制核心,LabView为上位机软件开发平台的分布式多路温度调控系统。系统主要分为4大子系统,分别为以铠装K型热电偶和DAM-3038热电偶模拟量输入模块为主要组成部件的温度采集系统;基于LabView2015开发的上位机软件;以一块STM32F407为核心的微处理器部分以及以固态继电器(SSR)与电热丝为主要部件的温度控制部分。经过实际试验验证,该系统能够在保证设计的多路温度控制功能实现的情况下稳定运行,具有较强的实用性。     

HgCdTe heteroepitaxy on three-inch (112) CdZnTe/Si: Ellipsometric control of substrate temperature

The technique of spectroscopic ellipsometry (SE) has been utilized to monitor in real-time and precisely control the surface temperature of Hg_1−xCd_xTe during molecular beam epitaxy. Due to the temperature dependence of the Hg sticking coefficient under Hg-deficient growth conditions, the near-surface composition of an epilayer is extremely sensitive to surface temperature. SE data were acquired in real time and modeled using a previously established library of dielectric functions of Hg_1−xCd_xTe as a function of composition. Utilizing SE-generated compositional profiles as a guide, substrate heating power was adjusted in such a way as to minimize composition transients. To demonstrate the effectiveness of the technique, we have used SE to control the temperature of HgCdTe epilayer surfaces during deposition on three-inch (211)CdZnTe/ZnTe/Si composite substrates mounted on indium free holders.