Online safety monitoring method for electrical distance at intersection of power line and railway catenary

The invention relates to an online safety monitoring method for an electrical distance. The method comprises steps as follows: an image of a crossing point of a power transmission line and an electrified railway catenary is shot by a prearranged image collection device and is sent to a corresponding image analysis device; the image is analyzed by the image analysis device, and a monitoring distance between the power transmission line and the electrified railway catenary is obtained and is sent to a control center monitoring device at a far end; whether the monitoring distance coincide with a preset crossing point electric distance is judged by the control center monitoring device, and when the monitoring distance does not coincide with the preset crossing point electric distance, an early-warning prompt message is output. According to the online safety monitoring method for the electrical distance, real-time online monitoring can be performed on the electrical distance between the power transmission line and