Multi-locomotive fixing and rolling test platform

Abstract

The invention relates to a multi-locomotive fixing and rolling test platform which comprises two or three test platforms. Each test platform comprises a pair of counter-force frames (1), an upper axle (2) and test unit groups, wherein the test unit groups comprise test units having same number with single locomotive wheel pairs (41). All the test units adopt the structure that shafts of a track wheel pair (43) for supporting the locomotive wheel pairs (41) are connected with shafts of winding asynchronous motors (36), and the diameter/length ratio of the winding asynchronous motors is larger than 1; stator windings of all the winding asynchronous motors (36) of each test unit group are connected with a power grid by a three-phase switch I (63) of a stator three-phase bus bar (53) of each asynchronous motor, and rotor windings are connected in parallel to a rotor three-phase bus bar (49) of each asynchronous motor; and the rotor three-phase bus bars of the asynchronous motors of all the test unit groups are connected by a breaker (62). The test platform carries out a mutual accompanying test by multiple locomotives and has reliable synchronization and convenient test and can form the mutual feedback of energy, reduce the capacity of a power supply and save energy sources and cost.

Description

technical field [0001] The invention relates to a stationary rolling test bench for railway diesel locomotives, electric locomotives, main line trains and subway trains. Background technique [0002] The function of railway electric locomotives or diesel locomotives is to traction trains, and the main working conditions are traction and braking; the main working conditions of trunk line trains and subway trains are also traction and braking: [0003] 1. Traction working condition: After the electric energy obtained by the electric locomotive from the power grid is converted into an appropriate voltage (including frequency) by the converter, it is converted into mechanical kinetic energy by the traction motor, which can output the energy controlled by the driver at different speeds. The traction force makes the train accelerate or run at a steady speed; for a diesel locomotive, the internal combustion engine first converts the thermal energy of the fuel into mechanical energy...

AI Technical Summary

Problems solved by technology

The locomotive is tested on the test bench, and its speed is only reflected by the locomotive wheel speed, and the locomotive body does not move. Therefore, the equivalent moment of inertia reflected in the traction motor rotation dynamics equation is reduced to about 1 / 20 of the line test. Influenced by the locomotive closed-loop control system designed according to the line operating conditions, the speed may be unstable in the fixed rolling test

The dynamic instability of this locomotive is the main obstacle to achieve the accuracy of electrical synchronous regulation

[0016] 3) The stationary rolling test bench simulates the test process of two infinitely long straight rails through multiple independent track wheelsets. Many factors will cause the speed of each track wheel set to be different, making the locomotive mistaken for a certain track wheel set. Some wheel sets stop torque output due to idling, and then resume output to them, making the locomotive run unstable; especially when the locomotive starts, the output torque will stop frequently, making the locomotive unable to start normally

In order to ensure the synchronization of the rotation angles of each track wheel pair, the existing test benches mostly use bevel gears to connect all the track wheel shafts, which makes it have many mechanical parts, long intermediate connecting shafts, complicated test equipment, and reduced reliability.

At the same time, in order to align locomotives with different wheelbases, numerous mechanical connecting parts also make the mechanical adjustment workload heavy, and the long axis is still a factor that causes additional vibration and unsafety

[0017] In view of the problem of the mechanical synchronization scheme, some fixed rolling test benches in China adopt the scheme of adjusting the exciting current of each DC motor to make the rotational speed of the track wheel pair tend to be consistent, such as the 1981 "speed regulation of the dynamometer device of the diesel locomotive test bench". System", this kind of scheme needs to add an additional measurement and control closed-loop system. At the same time, because all the traction motors of the locomotive are connected in parallel in the "vehicle control" mode, and 2 to 3 motors are connected in parallel in the frame control, driven by the public power supply, these There is a coupling relationship between the speed and torque of the motor caused by the shared power supply. When the test bench adjusts the speed of a track wheel set, the speed of other driving wheels with coupling relationship will also change, resulting in cross interference

Moreover, the mechanical characteristics of the resistance braking DC motor are very soft, and the adjustment speed is slow. In practical applications, this solution needs to be adjusted repeatedly for a specific locomotive at least, which is very inconvenient to use. The problem of speed instability, it is difficult to achieve satisfactory synchronous rotation

[0018] 4) In view of the fact that the single locomotive test bench requires a large power accompanying electrical system, the investment is high

Therefore, the requirements for the test plant are high, the test operation is complicated, and due to the limitation of the site, it is difficult to build a fixed rolling test bench in the existing maintenance plant and section

[0020] In short, the existing multi-locomotive test bench scheme either adopts bevel gear synchronization, or relies on the excitation adjustment of the DC motor to achieve electrical synchronization; the former requires a lot of work to adjust to the different wheelbases of the locomotives before the test, while the latter Then in the test process, because the adjustment effect is always unsatisfactory, it takes a lot of time

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