The Research Of The Substation Grounding Grid Corrosion Mechanism And Life Assessment

Good grounding transformer substation is fundamental guarantee of the power system and the personal safety. It is the union of lighting protection grounding, protection grounding, working grounding and anti-static grounding electromagnetic interference. It may be very common that occurs corrosion under the action of chemical reaction, if the ground net through runs in the dark and damp environment for a long time. At present, the research on power system transformer substation grounding system mostly focused on grounding resistance calculation and the design of grounding network. The research on substation grounding body corrosion is only limited to the traditional metal corrosion mechanism. It has not been reported that difference environment conditions and the ground net though discharge current's assessment and influence on the grounding. Therefore, research on the substation ground network under difference working conditions, especially in the coastal and moist soil of bad circumstances, especially in the corrosion mechanism under the influence of the discharge current, setting up differentiation of expert system for substation grounding network corrosion, scientific assessment to the ground net though life have important engineering significance.The article firstly presents the main aims and classifications of power system grounding, and uses actual pictures to explain the encountered in the operation of the power system grounding network in corrosion, grounding corrosion classification and its consequences. In addition, it discusses the substation ground network corrosion and its life can not be assessed accurately and timely transformed brings.Furthermore,the article briefly explains the electrical properties of the soil and all kinds of natural environment and the impact of industrial and agricultural production on it, and lays a conductor foundation for the different time domain grounding body discharge lightning current and fault current and leakage current corrosion situations. Meanwhile, it analyzes the different fault types of grounding body current characteristics of lightning stroke, level of lightning current and fault current and leakage current of the time and places from the affected soil characteristics of grounding device of metal corrosion by setting examples of different lightning strike accidents both inside and outside of the substation, laying a foundation for the research on the mechanism of metal corrosion grounding body device. Besides, it analyzes the differences of potential and current distribution when the grounding device discharges lightning current and fault current and leakages current grounding conductor, laying a microscopic theory foundation for the next analysis of micro batteries with micro corrosion.Thirdly, the article analyzes the mechanism of grounding device corrosion from the macro and micro battery effects. It connects the corrosion mechanism with grounding device discharge lightning current and fault current and leakage current, reaching the discharge current and metal corrosion speed indicator, indicator reaction speed grounding device performance indicators. The third chapter builds the relationship between the discharge current and grounding device grounding resistance in the case of natural corrosion through the relationship between the discharge current and grounding device performance changes. It creates a theoretical foundation for the grounding device operation data statistical and grounding device assessment on the basis the basic data and operation experience.Last, through the theoretical analysis, we can inductive the considering the effects of discharge current under different working conditions of substation ground network corrosion mechanism and establish a more scientific and closer to the actual engineering application of substation ground network life assessment process, providing the theoretical foundation for the engineering application and data accumulation of next step.