An apparatus for controlling speed in railway vehicles, the apparatus comprising:
- a first controller configured to estimate a future train speed and to determine a first speed control to control a train speed based on a TTSLC (Time-To-Speed-Limit Crossing) that is a time taken by a train from a current time to exceed an ATP (Automatic Train Protection) speed profile that is an ATP speed limit;
- a second controller configured to determine a second speed control to control the train speed based on a difference between the ATP speed profile and actual train speed;
- and
- a selection unit configured to select the first speed control or the second speed control in response to the TTSLC and to output the selection to the train,
- wherein the second controller includes a first generation unit configured to generate an ATO (Automatic Train Operation) speed profile using the ATP speed profile, a second generation unit configured to generate a speed error that is a difference between the ATO speed profile and the actual train speed, and a third controller configured to output the second speed control by performing a PI (Proportionate Integral) control based on the speed error,
- wherein the first controller includes:
- a first estimation unit configured to estimate current train speed through a non-linear observer using train data including a propulsive force, a braking force and an acceleration of the train and to estimate track data including a track curvature and a track gradient;
- a second estimation unit configured to estimate future train speed using the estimated current train speed;
- a calculation unit configured to calculate the TTSLC through a time when the train exceeds the ATP speed profile while the train maintains a current acceleration or deceleration;
- and
- a fourth controller configured to output the first speed control using the calculated TTSLC,
- wherein the first estimation unit includes:
- a third generation unit configured to generate a dynamic model of the train using the train data and the estimated track data;
- a design unit configured to design the non-linear observer based on the generated dynamic model, the train data and the estimated track data;
- and
- a third estimation unit configured to estimate the current train speed through the non-linear observer based on the current acceleration,
- wherein the third estimation unit performs:
- estimation of the current train speed using previous train speed and previous track data;
- estimation of the current acceleration using the estimated current train speed, current train data and the previous track data;
- determination of an estimation error using a difference between acceleration included in the current train data and the estimated current acceleration;
- prediction of current estimation error covariance using previous error covariance, process noise covariance, and a process Jacobian matrix;
- determination of current Kalman filter gain using the predicted current estimation error covariance, a current measured noise covariance and a Jacobian matrix of measurement variable;
- calibration of the predicted current estimation error covariance using the determined current Kalman filter gain;
- and
- estimation of the current train speed by calibrating predicted train speed using the determined estimation error and the determined current Kalman filter gain.