JEM电机引接线带电作业中人在强电场下的保护

 

In this paper, we will introduce the concept of strong electric field protection and the principle of appliance. Through knowledge explanation and appliance principle introduction, master the requirements of strong electric field protection in live working, the principle and technical requirements of shielding clothing.

 

 

 

带电作业中所遇到的电场几乎都是不对称分布的极不均匀电场。作业人员在攀登杆塔或变电站构架，由地电位进入强电场的过程中，构成了各种各样的电场。JEM电机引接线带电作业中人在强电场下的保护

 

The electric fields encountered in live working are almost all extremely uneven electric fields with asymmetric distribution. In the process of climbing tower or substation frame and entering strong electric field from ground potential, operators form a variety of electric fields.

 

 

运行中的导线其表面及周围空间存在着电场，且属于不均匀电场，其表面的电场强度高于周围空间的电场强度。影响导线表面及周围空间电场强度的因素是多方面的，主要包括：输电线路运行电压、相间距离与分布、导线对地高度、分裂导线数目、分裂距与子导线的直径、导线表面状况、当地气象条件等。根据理论计算，500kV系统中若采用LGJ—300型导线、四分裂、分裂距45cm×45cm,则导线表面最高场强为1550/2250kV/m (有效值/峰值)。

 

The electric field exists on the surface and the surrounding space of the running conductor, which belongs to non-uniform electric field. The electric field intensity on the surface of the conductor is higher than that in the surrounding space. There are many factors that affect the electric field intensity on the surface of the conductor and the surrounding space, including the operating voltage of the transmission line, the distance and distribution between phases, the height of the conductor to the ground, the number of split conductors, the split distance and the diameter of the sub conductors, the surface condition of the conductor, the local meteorological conditions, etc. According to the theoretical calculation, if lgj-300 type conductor is used in 500kV system, with four splits and split distance of 45cm × 45cm, the maximum field strength on the conductor surface is 1550 / 2250kV / M (effective value / peak value).

 

 

在带电作业的全过程中人体处于空间电场的不同位置，对空间电场的影响是不一样的，人体各部位体表的场强也是不一样的。将人体看成导体，由于静电感应，当人体处于地面时，整个人体处于地电位，人体形成突出，一般来说头部体表场强最高；当人体在导线与地面间电位悬浮（相当于中间电位作业时），沿着电场的纵方向的人体突出部位（头、脚）体表场强最高；人体与导线电位相等后，人体的突出部分将发出电力线，此处的体表场强最高；在操作人员进行电位转移的瞬间，手接触导线时手与导线之间的气隙处的场强非常大，会导致手指与导线之间发生放电，直到手指握住导线后，放电才会停止。带电作业中人在强电场下的保护

 

In the whole process of live working, human body is in different position of space electric field, which has different influence on space electric field, and the field strength of human body's surface is also different. The human body is regarded as a conductor. Due to electrostatic induction, when the human body is on the ground, the whole human body is at the ground potential, and the human body forms a protrusion, generally speaking, the field strength of the head body surface is the highest; when the human body is suspended between the wire and the ground (equivalent to the operation of intermediate potential), the field strength of the body protrusion (head and foot) along the longitudinal direction of the electric field is the highest; the potential of the human body and the wire is the same After waiting, the protruding part of the human body will send out the power line, where the body surface field strength is the highest; at the moment of potential transfer, when the hand contacts the wire, the field strength at the air gap between the hand and the wire is very large, which will cause the discharge between the fingers and the wire, and the discharge will not stop until the fingers hold the wire.