Traction control system for electric multiple units

An oil tank ventilation device for a hydraulic brake unit of a tramcar, comprising a vent plug, a sealing ring, a gas guide hole and a gas guide pipe;

• wherein the gas guide hole is a through-hole structure arranged at an upper end inside an integrated valve block;
• the vent plug is arranged inside an electrical element protection case, and performs gas exchange from an outside through a harness hole provided on the electrical element protection case;
• the vent plug is mounted in the gas guide hole on the integrated valve block which is on one side of an interior of the electrical element protection case, and the vent plug is coaxial with the gas guide hole and is communicated with an inner chamber of the integrated valve block through the gas guide hole;
• the sealing ring is mounted at a junction of the vent plug and the integrated valve block;
• and, one end of the gas guide pipe is mounted with the gas guide hole on the integrated valve block which is on one side of an interior of an oil tank, while another end of the gas guide pipe is stretched into an air chamber above the interior of the oil tank, and the gas guide pipe is coaxial and communicated with the gas guide hole.