Relative velocity based train protection method and apparatus

A relative velocity based train protection apparatus, comprising:

• a first generation unit configured to calculate safe spatial-temporal trajectory information of a preceding train and a following train in two successive trains in a stopping process using an electronic map and autonomous velocity measurement and positioning information in combination with performance of the preceding train and the following train, wherein the safe spatial-temporal trajectory information comprises:
• a curve of a position changing with time;
• an obtaining unit configured to obtain the safe spatial-temporal trajectory information of the preceding train by the following train through vehicle-to-vehicle communication;
• a solving unit configured to create a safety condition by the following train according to a constraint that a position of the following train does not surpass a position of the preceding train at any time in combination with the safe spatial-temporal trajectory information of the preceding train and the following train, and solve an EBI velocity of the following train;
• and
• a comparison unit configured to determine, by the following train through comparison, whether a current measured velocity v2(t0) of the following train exceeds the EBI velocity E2(t0) of the following train, and output an emergency braking instruction to make the following train decelerate until the following train stops in response to v2(t0)>E2(t0), wherein
• the first generation unit is specifically configured to:
• obtain, by the preceding train, own velocity v1(t0) and position information x1(t0) using the velocity measurement and positioning technology, and obtain, by the following train, own velocity v2(t0) and position information x2(t0);
• obtain, by the preceding train, most unfavorable slope acceleration β1 during emergency braking and maximum emergency braking acceleration α1, and obtain, by the following train, most unfavorable slope acceleration β2 from triggering of emergency braking to stopping, a duration of traction phase δ2, maximum traction acceleration γ2, a duration of idling phase ε2, and emergency braking acceleration α2 that is guaranteed under a most unfavorable condition;
• take, by the preceding train, measured rear position and velocity information as an initial state, and calculate the curve of the position of the preceding train changing with time during braking according to a model of a train immediately implementing emergency braking in combination with train braking performance and line parameters obtained by query;
• and
• take, by the following train, measured train head position information and EBI velocity as an initial state, and calculate the curve of the position of the following train changing with time during braking according to a safe braking model stipulated in IEEE1474.1 in combination with train traction and braking performance and line parameters obtained by query.