Based On Embedded Image Processing Platform High Temperature Molten Salt Level Measurement Device Research

With people's attention to renewable energy, tower solar thermal power generation has attracted more and more attention in the field of new energy due to its high efficiency and zero-pollution. As the main component of the tower solar thermal power generation system, the double tank molten salt heat storage system can directly reflect the energy storage of the heat storage system, which determines the safe and stable operation of the solar thermal power generation system. However, due to the high temperature and high pressure inside the heat storage tank, the conventional method can't be used to measure the molten salt level for a long time. This topic aimed at the problem of molten salt level measurement of heat storage tank, the main research contents for:(1). Based on the theory of optical triangulation, found a mathematical model of the molten salt level measurement in heat storage tank. Where, image acquisition system is equipped with lens imaging system, incident beam is a line laser.(2). The weighted average method is used to detect the laser line center position, and laser line sub-pixel shift also can be detected. To solve the problem of accurate detection laser line position in high noise image, an algorithm of the target area filtering is designed.(3). To solve the problem of liquid sloshing in the molten salt quick inlet and outlet heat storage tank, double laser line detecting method is designed. And to solve the problem of periodic sloshing caused by the vibration of the liquid level in the tank, autocorrelation integral method is designed. These two methods can effectively weaken the effect of liquid sloshing on liquid level measurement.(4). Designed and implemented liquid level measuring device based on ARM9 embedded image processing platform. To solve the device installation error, parameter calibrating algorithm based on least square method is designed. And UCOS-II operating system on embedded platform is transplanted, the human-computer interaction interface is designed. The device has advantages of easy operation, reliability, stability, low cost and strong practicability.Finally, the real-time, accuracy and rapidity of the molten salt level measurement device are verified by experiments, measure range and accuracy have reached the requirements of measurement. In addition, the device is installed outside the heat storage tank, which is convenient for the installation and maintenance in the later period.