Rail transit train wheel diameter calibrating method

Abstract

The invention discloses a rail transit train wheel diameter calibrating method. The method comprises the steps that if the rail transit train wheel diameter calibrating conditions are met, the increase amplitude of rail transit train wheel diameter error tolerance values during slipping and idling are obtained correspondingly; the actual running distance of a train of which train wheels slip and the corresponding number of accumulated pulses thereof are obtained; the number of actual running accumulated pulses of the train of which the train wheels idle and the corresponding actual distance of a transponder in pair are obtained; a train wheel diameter value is calculated according to each cycle of the fixed pulse number of a speed sensor and the actual distance of the transponder, if an absolute value of the difference between the train wheel diameter value obtained through calculation of the round and a calibrated train wheel diameter value of the last round is smaller than the wheel diameter error tolerance value, the wheel diameter calibrating succeeds, and otherwise the wheel diameter calibrating fails; if calibrating succeeds, the train wheel diameter value is the arithmetic average of the train wheel diameter value obtained through calculation of the round and the calibrated train wheel diameter value of the last round; and if calibrating fails, the steps are repeated to calibrate the wheel diameter again.

Description

technical field [0001] The invention relates to the field of rail transit, in particular to a method for calibrating the wheel diameter of rail transit trains. Background technique [0002] In the field of urban rail transit safety signals, train speed and distance measurement (referred to as speed measurement and distance measurement) and train positioning are two key technologies of the automatic train protection system (Automatic Train Protection, referred to as ATP) with a safety level of SIL4 in the on-board signal system. The basis for other ATP / ATO functions in the on-board signaling system in the signaling system. The accuracy of speed measurement, distance measurement and positioning is one of the key factors that determine the high availability and efficiency of rail transit signal system functions. Whether the wheel diameter is calibrated or not, the wheel diameter calibration error will greatly affect the accuracy of the speed measurement, ranging and positionin...

AI Technical Summary

Problems solved by technology

There are many methods for automatic calibration, such as GPS wheel diameter calibration (see "Research on Wheel Diameter Calibration Method for Train Combination Positioning Based on Gray Theory"), but it is difficult to implement in places where underground rail transit or elevated lines are dense; another example is structured light source Projection and image fitting method (see "Vehicle Wheelset Diameter Online Detection Method and Device"), but this method has requirements for train speed, which affects operational efficiency. At the same time, it is assumed that the wheels are circular for fitting, and the accuracy is open to question In addition, there are pulse distance measuring devices and speed sensor pulses combined with measuring wheel diameter method (referring to "calibration method and calibration system of train wheel diameter"), but this method has used two kinds of sensors, and fully believes in the distance measuring sensor device accuracy, There are errors in the method, and the errors are accumulated, which does not meet the requirements for high-precision wheel diameter calibration

[0004] In the Chinese patent application 201310654448.0, the wheel diameter automatic calibration process is introduced, and this method has several defects: 1. Measure the initial wheel diameter value of the train, which may be the factory default value, and use this when accumulating the moving distance between transponders The cumulative moving distance calculated by the wheel diameter value has errors, and the error is relatively large, because the real wheel diameter value may have errors from the factory default value; 2. When judging the validity of the measured wheel diameter value, the pre-stored The fixed parameters in the database, and no other equipment is introduced to dynamically update the error. If the fixed parameters are too large, this method may tolerate wrong wheel diameter calibration, which may have safety risks. If the fixed parameters are too small, it will Reduce the usability of the wheel diameter calibration function; 3. According to the requirements of "train positioning / train speed measurement" in 1474.1 IEEE Standard for Communications-Based Train Control (CBTC) Performance and Functional Requirements (IEEE1474.1 Communication-Based Train Control CBTC Performance and Functional Requirements Standard), if the positioning and speed measurement functions are based on If the wheel diameter is large, then two factors need to be considered when compensating the uncertainty of train positioning and speed measurement, one is wheel idling and slipping, and the other is the error caused by wheel rotation, wear or replacement

This patent application does not consider the impact of idling and skidding in the process of accumulating the moving distance of the train between the double transponders, and the usability is insufficient; moreover, the patent application does not consider abnormal scenarios, such as the processing method when emergency braking occurs , if calculated according to the method described in the patent application, it may lead to incorrect calculation results and safety risks

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