For the high-speed rail EMU driving system, the driving occlusion method is an important technology. This article will introduce you to several specific methods of traffic blocking, hoping to communicate with the majority of railway enthusiasts**.
Before introducing the traffic occlusion method, let's first take you to clarify the concept of occlusion: the characteristics of EMU trains running in the section (occlusion partition) are: the running speed of the train is high, the mass is heavy, the braking distance is long, and it cannot be avoided. In order to ensure the safety of the train in the section, three necessary conditions are required for the train to run from the station to the section:
First, it is necessary to verify that the interval is idle;
Second, there must be a certificate to enter the interval;
Third, it is necessary to implement interval blocking.
The voucher for the permission to occupy the section is usually the outbound signal of the station and the signal display of the section through the signal. Only one train is allowed to run in the same section, and once the train occupies the section, it is blocked.
The function of the traffic block method is to control the train to maintain a certain distance between the train to ensure the safe operation of the train. There are two main methods of occlusion: one is the spatial interval method and the other is the time interval method.
1) Time interval method: The time interval method is to run trains running in the same direction at a specified time in a section.
2) Spatial spacing method: The method of dividing the line into several line segments (sections or occlusion partitions) on the main line of the railway through the line demarcation point (station or line station, automatic block color light signal), and only allowing one train to run at the same time and in the same space is called the spatial spacing method. The spatial interval method divides the railway line into a lot of sections (or block partitions), each section can run trains in a certain period of time, can improve the driving capacity, only one train is allowed to run in a section, and the train can run in the interval according to the specified speed, which can not only improve the speed of the train, but also accelerate the turnover of rolling stock (EMU), so it is a widely used method.
Implement a system of interval blocking.
1) artificial blocking: adopt the voucher of the section occupied by the train by adopting the electric road sign or the road sign (road ticket), and check whether the section is idle by the attendant of the receiving station.
Give the road sign (sign) to the driver.
Put the road sign (plate) you hold into the collector designed by the station.
Get a road sign (sign) from the dispenser
Exchange signs (signs) at the signal office
2) Semi-automatic blocking: It is an occlusion method in which the outbound signal automatically closes after the train departs according to the signal display. Its characteristics are: only one train is allowed to run between stations; Manual occlusion procedures; Manually confirm the complete arrival of the train and manually restore the blockage; The opening of the outbound signal is manually controlled, and the signal can be automatically closed after the train leaves the station, so it is called semi-automatic blocking.
3) Automatic blocking: It is an occlusion method that automatically handles the blocking procedures under the condition of interval occupancy inspection (track circuit, axle counting device), and the outbound signal automatically closes after the train departs with the signal display. It is characterized by: there is an interval occupancy inspection equipment; Only one train is allowed between stations; Automatically handle the occlusion procedures when the departure approach; Automatic confirmation of train arrival and automatic recovery of blockage. The outbound signal can be automatically opened and closed, so it is called automatic inter-station blocking.
Conventional automatic blockingThere are mainly three display automatic block and four display automatic block, generally set up ground signal, equipped locomotive signal, the traditional automatic block is usually called automatic block, in order to distinguish it from the automatic block equipped with ATC, so it is called the traditional automatic block.
Third, the display of the automatic block interval through the signal is as follows:
A green light allows the train to run at a specified speed, indicating that at least two block zones are free in front of the run.
Yellow light asks the train to pay attention to the operation, indicating that there is a block in front of the operation that is free.
Red light The train should stop in front of this signal.
The four display automatic block means that the signal has four states, which can predict the state of the three block zones in front of the train.
The characteristics are as follows:Green light:The train is required to run at the specified speed, and at least three occlusion zones are idle in front;
Green and yellow light:The train is required to run at a higher speed, with two occlusion zones in front of it being idle;
Yellow light:The train is required to run at reduced speed, and only one block is idle in front of it;
Red light:The train is required to stop, and the car is occupied in the front block area, and the train is not allowed to cross the signal;
The mobile block train control system is recognized as the most advanced signal system at this stage, and the subway lines planned and constructed at this stage are all mobile blocks, and the train control system adopts the target distance control mode, and there is no fixed block partition in the interval, only a logical block partition.
Mobile occlusion generally adopts large-capacity two-way communication between vehicles and ground, which is generally realized through wireless communication such as induction loop or free-wave antenna, leaking cable and waveguide. The tracking target point of the moving block is the tail of the preceding train, leaving a certain safety distance, non-fixed point, and the starting braking point of the rear train is determined by the performance calculation of the target distance, the target speed and the train itself, and is not a fixed point. Both of these points are non-fixed points, hence the term moving block, which has a smaller tracking run interval than a moving block.
The above is a brief elaboration of the EMU driving occlusion method, and I hope to communicate with more railway workers and enthusiasts to promote and learn from each other.