A power quality surveillance system is developed in this thesis. At present, our country power quality national standard was chiefly stipulated six quotas: frequency, harmonic and voltage deviation, three-phase imbalance, the voltage fluctuation and flicker, temporary power quality.Based on the analysis of the similar productions of other countries and manufacturers, we put forward our design...

In our country, power theft becomes more and more seriously in some enterprise. How to perfect the technology of preventing power theft to restrict this deed is a problem which most of power supply corporations are caring in a long time. To resolve this problem, this dissertation author researches deeply and makes two preventing power theft devices which be used in three-phase power supply sys...

The dial instruments are the primary tools for the measurement of electricity inelectric power industry. According to the regulations for the dial instruments, they mustbe calibrated periodically, but the instrument reading is not accurate in the classicalcalibration and the method is not efficient.The paper uses the technique of calibration with power source, the pointer of dialinstrument is ...

The automobile sketch multimeter is aimed at characteristic which include the smaller scale of automobile maintainability and repairability enterprise, in our country, and not quite well ability of professional technique level. But the intelligence examination instrument that we develope in addition to have function of common multimeter, also can measure the fire test function of automobile e...

AC sampling represents developing direction in the measurement of electric power parameters and grid harmonics analysis. Synch-sampling is an ideal AC sampling method, it may appear deviation (sampling synchronous deviation ) because of the limitation of minimum timing unit of timer and variety of signal frequence. Synchronous deviation caused by limitation of the timer has already been studie...

Bioelectrical impedance measuring technology is a developing technology that iscalling the attentions of the researchers, due to its low-cost, wealth of information andnon-invasive. This technology can extract biomedical information relating to humanbody\’s physiological and pathology status, through the change of electrical characters(impedance, admittance, permittivity etc.) in biologi...

The paper mainly discusses the design principle and chief techniques of a high accuracy programmable digital voltmeter. Measurement of AC and DC voltage, current frequency, period, temperature, and so on, are accomplished by the meter. Manual switching or self-adjusting range, displaying the results on liquid crystal and communicating with PC is fulfilled by the meter.The paper has introduced ...

In navigation systems ,higher and higher performancs have been needed by the inertia components for A few dacades. Accelerometers with low cost and high reliability are badly needed. Vibration Beam Accelerometer indicate its futer for its inhere characteristics. Vibrating Beam Accelerometer (VBA) is virtually a solid state accelerometer with an …

At present, many large-scale oil and gas fields have already entered a period of high water production, hydraulic fracturing is the primary means of stable development for oil fields. Usually regard hydraulic fracturing fracture geometry as the result of hydraulic fracturing, but there is no effective ways to judging the result of hydraulic fracturing, and very serious impact on the hydraulic...

With the development of the computer、communications、electronics、detect、machinery and NC, and other related technologies, control technology is also rapidly developing and has become the indispensable foundation technology in modern manufacturing systems. For Brushless DC motor control requirements, will help improve the control precision and is beneficial for system for complex proces...