加热温度是光纤熔融拉锥制造中的关键因素,直接影响器件的性能。为了提高加热区域温度的稳定性和可控性,设计了高压电弧加热装置,并对电弧加热、弧区温度和光纤预热进行了分析。设计了高频高压电源和电极。电源的电流和频率独立可调,采用电压闭环和电流控制确保引弧成功和提高电弧放电电流的稳定性,并分析了其放电过程。建立了弧区温度测量实验平台,采用红外热像仪测量加热中陶瓷棒的温度,得到了弧区温度。通过实验确定了频率、电弧控制电压以及加热距离与弧区温度的关系。通过电弧控制电压和通过加热距离控制电弧加热区的温度。通过计算得到电弧弧区的中心温度可达到1635℃,实验测得稳定性为2.37℃。建立了细径光纤(直径80μm)的加热模型,通过有限元的瞬态分析确定了预热时间,经过25 s,光纤加热区达到稳定。
The heating temperature is one of the key factors in the fiber fused biconical taper manufacture,which can affect the component performance. In order to improve the temperature stability and controllability in the heating region, the high- voltage arc heating device is presented and arc heating, heating region temperature and fiber preheating are studied. The high- frequency high voltage power source, in which the current and frequency can be adjusted independently, and electrodes are designed. The closed- loop controls of the voltage and current are applied to ensure the success of the arc ignition and the stability of the arc discharge current, and the discharge process is analyzed. The temperature detection device in which the infrared camera is adopted to measure the heating region temperature by the ceramic rod is designed. Through the analysis of experimental data, the relationships among the frequency, arc control voltage, arc current,heating distance and arc region temperature are determined. According to experiments and computation results, the temperature of the arc center region can reach 1635 ℃ within the stability of 2.37 ℃. Based on the established heating model for fine fibers with the diameter of 80 μm, the preheating time is computed by the transient analysis of the ANSYS software. It is shown that the temperature of the heating region can reach the stability by 25 s.