| Water resource is renewable,clean resource,the development of hydropower resource,not only can reduces the coal, oil and other mineral resources consumption, resulting in economic benefits; but also can protect the environment and achieve sustainable development. According to the specific conditions and characteristics of hydropower project,set the appropriate safety monitoring projects to monitor the stress,strain,seepage and other variables of hydropower project continuously and comprehensively,will play an important role in the hydropower project safety.The main study in this paper is vibrating wire sensors and differential resistive sensors.The two types of sensors possess a lot of advantages such as simple structure,precise measurement, well-adjusted to harsh environment, cost-effective, etc, thus they applied in the hydropower project widely.In response to the features of the two types of sensors,this paper proposed two specific acquisition schemes. At present, vibrating wire sensors drives in two ways:High-voltage twang and low-voltage with frequency up. This paper combines the two way’s advantage, proposed a feedback driving method,that is,first use the low-voltage with frequency up way,obtained the frequency f which is slight difference with the resonant frequency;second use the f as the driving frequency to drive the steel wire, the steel wire reach the resonate state very fast with large amplitude and dacay slowly,this can improve the measurement accuracy effectively. For differential resistive sensors, the main idea of signal sampling is use the MCU to set the bandrate of AD conventer,use the MCU10to control the analog switch on or off and sampling the data after AD conversion.The main work of this paper is finished the hardware and software design.This paper also propose a wireless transmisson scheme,which will be of positive signifiance for improving the system’s adaptability,scalability and economical efficiency. |
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