【作者】 刘赫；

【导师】 韩震宇；

【作者基本信息】 四川大学 ， 机械电子工程， 2005， 硕士

【摘要】 核电站压水堆堆芯中的燃料组件工作在高温、高压、高辐射循环水中,由于装配应力及热应力等因素的影响,燃料棒和组件的外形会发生变化,严重时会危及反应堆的安全,因此对燃料组件的变形进行定期检测具有实际意义。本文阐述了核燃料组件变形尺寸测量原理样机的设计过程,包括机械传动装置设计、光路系统设计、硬件电路设计和变形测量软件的数据处理,通过对模拟组件的检测,验证原理样机的可行性和测量精度。 核燃料组件变形尺寸测量系统利用激光扫描测量作为基本测量原理,利用了激光发散角小、强度高的特点,是一种理想的非接触测量方法,具有精度高、动态范围大、抗干扰等优点。本文介绍了通过比较测量,消除激光扫描所用的电机速度不均匀产生的误差,提高测量精度的方法。 本文中的传动装置为步进电机、蜗杆减速器和同步齿形带组成的开环伺服驱动系统,利用同步带传动比准确,传动效率高,传动功率范围大,传动平稳的特点实现对组件垂直方向准确的扫描运动。以氯丁橡胶材料制成的同步带还具有防水的性能,实现在水下直接测量。 本文的硬件电路和数据采集系统采用AVR高性能的mega系列单片机和硬件计数器的结合,实现高频脉冲填充测量法对信号脉宽进行高精度的测量。数据采集系统还采用半波采样边缘法对原始信号进行处理,减小电平的波动对测量精度的影响。 在最后的数据处理中提出利用BP神经网络对测量数据的非线性误差进行补偿和修正,通过软件方法消除由于光学器件自身的加工误差影响,进一步提更多还原

【Abstract】 At nuclear power plant, Nuclear Fuel Elements of pressurized water reactor core work in high temperature, high-pressure and intense radiation circulating water. For some reason such as assembly stress and thermal stress, fuel rod and fuel elements will distort, graveness transmogrification will endanger nuclear reactor. So it is necessary to check fuel elements. The paper expatiates design of Nuclear Fuel Elements deformation measurement system principle prototype, including mechanical driving equipment, laser scanning system design, circuit system design and data processing software system. Through detecting simulative Nuclear Fuel Elements to prove the correctness of philosophy of measurement and check the accuracy in measurement of the system.The system’s fundamental is laser scanning. Laser have characteristic with small divergence angle and high intensity. So laser scanning is a kind of excellent non-contact measurement methods with high-precision, wide dynamic range and anti-jamming. The thesis introduces a method of comparative measurement to eliminate the error that resulted from velocity discontinuity of electromotor used in laser scanning set and improve measure precision.The transmission gear of this measurement system is openloop servo system composed of step motor, worm reducer and synchronous belt. Synchronous belt have characteristic with accurate transmission ratio, high transmission efficiency, high transmission power and Synchronous belt made up of neoprene can work in water.Circuit and data acquisition system use high performance "Mega" series singlechip of AVR and hardware counter circuit to measure signal pulse width with pulse stuffing method. Data acquisition system deals with original signal with half-wave sampling edge signal detection method to reduce infection of level variation.At last, we propose using BP neural network to compensate and correct non-linear error, and eliminate the effect of mismachining tolerance of optical device,and improve measuring accuracy more.更多还原