Abstract
Development which progresses by leaps and bounds along with the science and technology, electronic technology widespread application in national economy in and so on industry, agriculture, transportation, aerospace, national defense development many domains, but the electronic surveying technology is also in the electronic technology carries on the information examination the important means that holds the pivotal function and the status in the modern science technology. The low frequency digital phase reflectoscope reflector in the industrial field is the general measuring tool which uses frequently, for instance the electrical network incorporation switches on when the electrical power system, requests two electrical network's electrical signals to be the same, between this request precise survey two power frequency signal phase difference. Also has surveys two row frequency signals the phase difference in the research network, in system's frequency characteristic to have the important meaning. In recent years, along with science's and technology's rapidly expand, many measuring instrument gradually to “the smart instrument” and “the automated test system” the development, this caused instrument's use to be quite simple, the function were getting more and more. Widely applies along with the phase measurement technology in the national defense, the scientific research, the production and so on each domain, to phase measurement's request also gradually to the high accuracy, the high intellectualized direction develops, in the low frequency scope, the phase measurement in departments and so on electric power, machinery has the especially vital significance, regarding the low frequency phase's survey, cannot satisfy the accuracy requirement which obviously with the traditional simulation indicator type measuring appliance needs, because along with the electronic technology as well as the microcomputer technology's development, the digital measuring appliance its high accuracy's survey resolution as well as the high intellectualization, the direct-viewing characteristic obtains more and more widespread application. Phase difference survey between the same frequency sinusoidal signal's in the electrician technology, the industrial automation, the intelligent control and the communication, the electron and so on many domains has the widespread application, like in electrician domain electrical machinery merit angle test, medium spillage of material angle determination and so on. Therefore, the phase difference measuring technique has the widespread use value.
Keywords：Phase、Measuring instrument、Low frequency、Power frequency
