基于单片机控制的高精度TEC温控

提出了一种使用单片机对半导体制冷器（TEC）进行高精度温度控制的方法。通过单片机采集TEC的温度,经过PID运算,发出控制脉冲,由可编程逻辑器件生成H桥的控制波形。通过对电流方向和导通时间的控制,达到对温度控制的目的。     

大功率半导体激光器驱动电源及温控系统设计

为了解决大功率半导体激光器的输出波长和功率的稳定性问题,设计了一套大功率激光器恒流驱动电源及温控系统。利用深度负反馈电路实现对激光器驱动电流的恒流控制,采用硬件比例-积分（Proportional-Integral,PI）温控电路结合恒流驱动,控制半导体制冷器（Thermoelectric Cooler,TEC）的工作电流,实现激光器工作温度的精确控制。所设计的驱动电源可实现输出电流0~12.5 A连续可调,同时具有电流检测、过流保护、晶体管-晶体管逻辑（Transistor-Transistor Logic,TTL）信号调制等功能。所设计的温控系统的控制精度可达到0.05℃,同时设定温度连续可调,温度可实时监测。实验结果表明该设计能够保证稳定的电流输出和温度控制,满足大功率激光器的使用要求。     

高精度激光器电流驱动与交流温控系统设计

半导体激光器作为原子磁强计的重要组成部分,其波长和功率主要由电流和温度决定,而传统的直流温控系统会对磁强计产生磁场干扰。针对高精度电流控制、温度控制和磁场干扰问题,设计了一种激光器恒流源驱动和交流控温系统。首先,设计基于功放的高精度激光器恒流源驱动系统;然后,设计交流温度调制解调检测和交流加热驱动系统;最后,采用STM32控制器、高精度AD采集和DA输出结合温度模糊自适应PID控制算法进行高精度温度控制。实验结果表明:在42℃温度下控制精度为0.005℃,在32 mA电流下稳定度为0.5 A,为激光器光功率和波长稳定性奠定基础。     

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。     

光纤耦合激光器驱动与控制技术研究

针对一种将多个半导体激光器(LD)芯片串联驱动,通过光纤耦合进行功率合成,构成光纤耦合高功率输出激光模块的特殊驱动要求,研发了小型化高效率激光电流源组件和小型化高效率半导体制冷(TEC)LD模块温度控制组件。组件工作温度范围为-45℃～55℃,实验证明达到了设计性能指标要求。建立了LD模块驱动电流源电路的数学模型,提出了LD模块电流源控制电路的数字化实现方法,并利用ADuC831单片机实现了数字化设计。给出了一种基于TEC的LD模块温度控制组件的结构,建立了简化、实用的温度控制系统数学模型,对TEC的性能系数ξ、控制端的热量Qc和TEC的工作电流I进行了寻优控制,减小了激光器输出波长随温度的漂移。     

基于STM32的高精度温度控制系统设计

设计一种使用STM32单片机来控制半导体制冷器TEC实现高稳定度、高精度温度控制系统,整个温度控制系统主要包括:STM32单片机最小系统、温度控制模块、温度控制串口上位机、PID算法、TEC等。通过对温度控制模块进行改良,来降低开关损耗,提升电路的工作效率以及可靠性,同时将积分分离PID算法改进为变速积分PID算法,实现稳定、高精度的温度控制。     

TEC 的高精度半导体激光器温控设计

热电制冷器（TEC）作为半导体激光器（LD）的制冷方案,具有体积小、易于控制等优点。但基于TEC 的制冷方案中TEC 的制冷功率和目标散热功率之间需要有良好地匹配关系,否则将会导致制冷不足或者导致功耗过大。根据LD 组件热负载匹配TEC 制冷功率,并通过比例-积分-微分（PID）控制方法实现温控参数的优化设计,实现了基于TEC 的LD 温度控制系统。经实验验证:该系统能够对LD 的工作温度实现控制范围为5℃~41℃、稳态误差小、控制精度为0.05℃的高精度、高稳定性控制,并在高精度的波长测试中得到了很好的应用。     

热电制冷器的等效电路模拟与分析

作为半导体激光器组件的重要一部分，热电制冷器（TEC）工作特性的模拟对激光器组件的设计与优化有着重要的意义。根据实际器件的结构模型，建立了考虑各种影响因素所造成的附加热阻和接触电阻的数学模型，进而推导出TEC的等效电路模型。用SPICE进行了TEC各种特性的仿真和讨论，分析了环境温度、制冷功率、附加热阻、接触电阻、工作电流以及电流源等对TEC工作特性的影响。采用等效电路模拟对于TEC的设计、优化和应用控制是一种有效的方法。     

高稳定度半导体激光器电源

设计并实现了一个高精度的半导体激光器驱动系统, 该系统包括温度控制和电流控制两部分。温度的控制范围为室温下±1.50×101 K, 控温精度优于1.81 mK, 标准差小于0.20 mK。电流的调节范围为0~2.00×102 mA, 纹波小于1.00×102 nA。该系统驱动外腔半导体激光器时可以保证激光器输出的频率稳定度在10 s内达到1.00×10-9, 满足原子分子物理和激光光谱学等领域对高精度激光器的需求。     

一种半导体激光器的精密温度控制电路

为了使半导体激光器(Laser Diode,LD)输出稳定的波长,必须精确控制对其特性影响很大的工作温度。以单片机为控制核心,采用高精度的负温度系数热敏电阻(Negative Temperature Coefficient resistance,NTC)结合半导体制冷器(Thermal Electronic Cooler,TEC)的方案,对TEC的驱动采用脉宽调制(Pulse Width Modulation,PWM)方式和“H”桥式电路来实现,研制了一种对2A电流的半导体激光器进行精密温度控制的电路,控制精度可达±0.1℃。     

大功率LED有源温控系统的开发

由于大功率LED供电时其大部分能量转化为热能,如果热量不能有效散出,将严重影响其光照亮度及其使用寿命。为了大功率LED散热的实际需要,提出并实现了一种LED有源温控系统的开发,采用热电制冷效应,使用LED驱动器本身作为制冷器的驱动电源,同时建立基于半导体传感器的温控监测电路,通过内部数字PI调节器形成一个完整的闭环控制系统,最后获得LED有源温控系统的具体配置方式,并分析测试的数据结果,展示了有源温控系统的准确性和可靠性。     

Solid-state refrigeration for cooling microprocessors

Thin-film thermoelectrics (TECs) are potential candidates for cooling microprocessors due to their large cooling power density and ability to integrate with packages. In addition, there are no moving parts or noise generated during their operation. In particular, thin-film TECs offer the ability to cool localized regions of high heat flux (hot spots) in the die selectively, which is very useful for chips with nonuniform power maps. In this paper, we theoretically analyze the performance of thin-film TECs for reducing the junction temperature at hot spots in a die. We report the reduction in junction temperature for a representative power map as a function of input power to the TEC films for the first time. The potential benefits and limitations of scaling the TEC legs are calculated by solving the general TEC equations within a fully three-dimensional numerical model of the assembled die and package. Parasitic electrical contact resistance and back conduction from the hot-side to cold-side through any encapsulating or material surrounding TEC legs are also included in the model. Model calculations are performed for TEC figure of merit (ZT) values of 1 and 3 (for comparison). We determine an operating envelope for the TECs that leads to an optimum cooling capability. The impact of operating the TECs are calculated as well taking into account the temperature increase of the heat spreader due to heat influx from the hot-side of the TEC. It is shown that material breakthroughs as well as process improvements could enable solid-state refrigeration to be an attractive candidate for spot cooling in microprocessors.     

Study on a cooling system based on thermoelectric cooler for thermal management of high-power LEDs

To improve the heat dissipation of high-power light-emitting diodes (LEDs), a cooling system with thermoelectric cooler (TEC) is investigated. In the experiment, the 6 × 3 W LEDs in two rows are used to compose the light source module and the environment temperature is 17 °C. The temperatures of heat dissipation substrate of LEDs and cooling fins of a radiator are measured by K type thermocouples to evaluate the cooling performance. Results show that the temperature of the substrate of LEDs reaches 26 °C without TEC. However, it is only 9 °C when the best refrigeration condition appears. The temperature of the substrate of LEDs decreases by 17 °C since the heat produced by LEDs is absorbed rapidly by TEC and dissipated through the radiator, and the junction temperature of LEDs reaches only 45 °C which is much lower than the absolute maximum temperature of LEDs (120 °C). The experiment demonstrates that the cooling system with TEC has good performance.     

可调谐半导体激光器的精密控制系统设计

为了满足高精密测量领域对半导体激光器高稳定度的要求,设计了一种高稳定度、低噪声的半导体激光器控制系统。该控制系统由电流驱动和温度控制两部分组成,电流控制部分采用负反馈控制保持电流稳定,温度控制部分采用高度集成的MAX1978作为主控芯片,驱动半导体制冷器进行温度补偿。经过实验验证,电流在200mA范围内连续可调,电流控制精度高达1A,在3kHz~100kHz带宽内交流噪声有效值小于300nA,长期温度漂移小于2m℃。结果表明,该系统可用于驱动分布式反馈外腔半导体激光器和分布式布喇格反射半导体激光器。     

Numerical analysis on heat transfer of laser diode module by equivalent electrical network method

Because it is complex and inconvenient to use the common temperature field calculating method and experiment method, for arialyzing heat transfer properties of laser diode module （LDM）, an equivalent electrical network method is presented in this paper. Simulation results show that the temperature stability is closely related to ambient temperature, heat sink, LDM current and TEC current. Ambient temperature and TEC controller are the dominant terms effecting on temperature control in practice,     

大功率蓝光固体激光器的温控设计

蓝光固体激光器目前在很多领域有广泛的应用。为了解决平凹腔蓝光固体激光器晶体在工作中因热效应问题产生的影响,针对激光的增益介质Nd:YAG晶体和用以倍频的LBO晶体,采用半导体制冷器(TEC)准确控制其工作时的温度。采用MCS51单片机作为微处理器,DS18B20温度传感芯片采集温度信号,运算放大器及大功率达林顿管组成功率驱动电路驱动半导体制冷器,PID算法根据实时采集的温度调节TEC的工作电压,采用AD芯片对输出给TEC的电压进行采样监控。整个系统在实验过程中,经PID参数调试取得了满意的控制效果。     

Electric Power Generation from Thermoelectric Cells Using a Solar Dish Concentrator

In this paper, design details, theoretical analysis, and outcomes of a preliminary experimental investigation on a concentrator thermoelectric generator (CTEG) utilizing solar thermal energy are presented. The designed CTEG system consisted of a parabolic dish collector with an aperture diameter of 1.8 m used to concentrate sunlight onto a copper receiver plate with 260 mm diameter. Four BiTe-based thermoelectric cells (TEC) installed on the receiver plate were used to convert the concentrated solar thermal energy directly into electric energy. A microchannel heat sink was used to remove waste heat from the TEC cold side, and a two-axis tracking system was used to track the sun continuously. Experimental tests were conducted on individual cells and on the overall CTEG system under different heating rates. Under maximum heat flux, a single TEC generator was able to produce 4.9 W for a temperature difference of 109°C, corresponding to 2.9% electrical efficiency. The overall CTEG system was able to produce electric power of up to 5.9 W for a 35°C temperature difference with a hot-side temperature of 68°C. The results of the investigation help to estimate the potential of the CTEG system and show concentrated thermoelectric generation to be one of the potential options for production of electric power from renewable energy sources.