| With the rapid development of industrialization, electric power industry has entered the stage of big power grid,high voltage,long distances,high capacity, and the spatial grid structure has become increasingly complex. So it is more and more important that the Power Systems has safety and smooth running. In the Power Systems, the pollution flashover accident of external insulation of the electric transmission and transformation equipment is always an important factor affecting the safe operation of the system, which is one of problems troubling systems at home and abroad. How to prevent pollution flashover from happening is an important task in the current department such as the power system designing, construction, manufacturing, scientific research and running department.Based on above backgrounds, analyzing the series of measuring methods of insulator's pollution and contrasting various conductance measurement methods, the thesis designs the electrical conductivity and ESDD meter based on ARM Cortex-M3. It can measure the equivalent salt of insulators'surface to ensure the soluble conductive material quantity in dirtiness layer. Thus it can judge the pollution level from the section of electrical elements, and adopt an anti-fouling flash measure and guide timely cleaning. ARM MCU is the control core in the meter, which can achieve automatic survey. The meter not only has the function of ESDD (Equivalent Salt Deposit Density) measure, but also the function of measuring the temperature and electrical conductivity of general solution which has extensive practicality.In hardware design, the ARM microcontroller with powerful function is selected as the core components. The enlarging of the conductance and temperature can auto-switch range in large scope. About the choice of sensors, the SDL-1 K=1 laboratory conduction electrode is selected, and they can completely replaced DJS-1 or imported conductance electrode. And choosing the clock chips DS12887, which can be used to display the time and can be used producing the signal source by programming. The meter with LCD display, can show various information, and micro printer can print test information and test time to file for future reference. In the transplant of embedded operating system, the kernel structure and function of the embedded real-time operating systemμC/OS-Ⅱare introduced at first. Then theμC/OS-Ⅱreal-time operating system is successfully ported on microprocessor LM3S1138. The software framework of data acquisition and human-computer interface module are presented. In the hardware of the anti-interference measures, signal shielding techniques and principles of grounding systems are introduced. In the software measures of the anti-interference, a median filtering method of average value of digital smooth filtering is used to overcome pulse disturbance.The design adopts ARM single-chip microcomputer technology, achieving a machine multi-functional purpose, which can also be used for several technical indicators and test, such as the temperature test, the ESDD test and conductivity test and work out the results of the test. It can overcome the reading error by using digital display, and overcome the accumulative error by using the monolithic system. Besides, it makes full use of the software resources to reduce the cost of hardware. The meter has the characteristics of small volume, easy to carry, low power consumption and reliable performance, which is suitable for industrial control work environment and meet the practical demands.
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