750kV超高压变电站职业病危害因素调查

Investigation of occupational hazard of 750 kV extra high voltage substations

目的了解750 kV超高压变电站主要职业病危害现状。方法于2019年7月,通过对变电站1、变电站2、变电站3、变电站4、变电站5、变电站6和变电站7等750 kV超高压变电站六氟化硫、工频电场和噪声等职业病危害因素进行调查和检测,分析作业人员在巡检过程中接触的六氟化硫水平、工频电场及噪声强度。结果 7座750 kV超高压变电站的358个六氟化硫检测点结果合格率为100.0%;工频电场8 h时间加权平均值结果合格率为100.0%,847个工频电场检测点中,工频电场检测超标率为64.3%,不同变电站和巡检区域工频电场检测超标率差异均有统计学意义(χ^(2)=87.52、50.86,P<0.01);其中断路器巡检区域工频电场超标率最高(94.4%,34/36)。7座变电站噪声强度检测结果为41.1~79.7 dB(A),合格率为100.0%。结论 750 kV超高压变电站运维工接触的六氟化硫、工频电场和噪声均符合职业接触限值要求,主变压器、电容器、电抗器、母线、开关等巡检区域存在较高的工频电场辐射,应在运行过程中加强设备选型、选用机器人巡检、调整巡检时间,以降低变电站运维工工频电场接触强度。

Objective To understand the current status of major occupational hazards in 750 kV extra high voltage(EHV)substations.Methods In July 2019,through investigating and detecting the sulfur hexafluoride,power frequency electric field and noise occupational hazards of 750 kV EHV substations in substation 1,substation 2,substation 3,substation 4,substation 5,substation 6 and substation 7,the exposure intensity of the sulfur hexafluoride,power frequency electric field and noise intensity that the operators are exposed to during the inspection process were analyzed.Results The qualified rate of 358 sulfur hexafluoride test results was 100.0%of the seven 750 kV EHV substations.The qualified rate of 8 h time-weighted average of the power frequency electric field of those 750 kV EHV substations contacted by operators was 100.0%.Among the 847 power frequency electric field detection points,the exceeding standard rate of power frequency electric field was 64.3%,and the differences in the power frequency electric field detection exceeding standard rates of different substations and inspection areas were statistically significant(χ^(2)=87.52,50.86,P<0.01).The highest exceeding standard rate of power frequency electric field was the circuit breaker inspection area(94.4%,34/36).The noise intensity test results of the seven EHV substations were 41.1-79.7 dB(A),and the qualified rate was 100.0%.Conclusion The sulfur hexafluoride,power frequency electric field and noise that the operators contacted in 750 kV EHV substations meet the requirements of occupational exposure limits.The inspection areas of main transformers,capacitors,reactors,bus bars and switches have high power frequency electric field radiation,should be select equipment iand give priority to robot inspection,and reasonably adjust the inspection time to reduce the intensity level of substation operators'exposure to power frequency electric field.