# Research on a Comprehensive Evaluation Method of Train Anti-Slip System Performance
## 4 Construction of a Comprehensive Test Platform for Anti-Slip Evaluation
### Calculation Results of Evaluation Indexs for Anti-Slip System  
The comprehensive evaluation method of train anti-slip system performance should be able to reflect the performance of the same anti-slip system under multiple slipping conditions, and also have the ability to compare different anti-slip systems horizontally (the differences in anti-slip systems are mainly reflected in anti-slip control strategies or air brake system parameters and components). Therefore, on the semi-physical simulation platform, based on the same air braking system, the anti-slip control strategies under the following two different speed difference criteria were tested, as shown in Table 13. The table shows the speed difference between the vehicle speed and axle speed represents the axle deceleration, and points A, B, and C represent the control points in the anti-slip control strategy that control the slipping of the wheelset [13]. Each control point corresponds to a detection criterion and action status. For example, under AW3 working condition, the train load is 57,780 kg, AW0 is 49,580 kg, and the initial braking speed is 200 km/h. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Axle Numbers** & **0–5\%** & **5–10\%** & **10–20\%** & **20–30\%** & **30–40\%** & **>50\%** \\ \hline Error of axle 1 of T & & & & & & \\ vehicle (\%) & 11.352 & 16.903 & 6.40172 & 52.4905 & 17.2723 & 0 \\ Error of axle 2 of T & & & & & & \\ vehicle (\%) & 6.2676 & 16.412 & 13.3894 & 6.47509 & 40.1843 & 0 \\ Error of axle 3 of T & & & & & & \\ vehicle (\%) & 2.2960 & 16.935 & 29.7074 & 4.08244 & 5.69206 & 0 \\ Error of axle 4 of T & & & & & & \\ vehicle (\%) & 36.530 & 14.532 & 20.5303 & 11.8072 & 12.8465 & 0 \\ Error of axle 1 of M vehicle (\%) & 16.503 & 12.386 & 18.6542 & 19.2538 & 30.2981 & 0 \\ Error of axle 2 of M vehicle (\%) & 0.4914 & 14.663 & 5.82357 & 26.0386 & 26.9687 & 0 \\ Error of axle 3 of M vehicle (\%) & 14.316 & 25.224 & 20.6282 & 9.84491 & 9.08482 & 0 \\ Error of axle 4 of M vehicle (\%) & 3.8996 & 6.3442 & 18.4675 & 23.4830 & 7.86394 & 0 \\ Average (\%) & 11.457 & 15.425 & 16.7003 & 19.1844 & 18.7763 & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Error statistics and mean calculation of test and simulation values. \begin{table}
\begin{tabular}{c c} \hline \hline
**Load** & **Brake Level** & **Adhesion Conditions** \\ \hline  & Dry rail \\  & 0.08 maximum adhesion coefficient \\  & Emergency braking & 0.07 maximum adhesion coefficient \\  & 0.06 maximum adhesion coefficient \\ AW3 & & 0.05 maximum adhesion coefficient \\ / & Dry rail \\ AW0 & 0.08 maximum adhesion coefficient \\  & Maximum service braking & 0.07 maximum adhesion coefficient \\  & 0.06 maximum adhesion coefficient \\  & 0.05 maximum adhesion coefficient \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Semi-physical simulation bench test conditions. We calculated the various parameters required for evaluating the performance of the anti-slip system, and some of the calculation results are shown in Figure 6. Selecting the calculation results of adhesion coefficient utilization, air consumption increase ratio, wheelset slipping energy, and average anti-slip valve action frequency under AW0 and maximum service braking conditions, it can be seen from Figure 6(a) that the adhesion coefficient utilization of anti-slip control strategy 1 was higher than that of anti-slip control strategy 2. Under this index, anti-slip control strategy 1 was better, while Figure 6(c) shows that the wheelset slipping energy of anti-slip control strategy 1 was higher than that of anti-slip control strategy 2. This also led to the poor performance of anti-slip control strategy 1 compared to anti-slip control strategy 2 in terms of the wheelset slipping energy index. Therefore, it can be found that a single evaluation index has difficulty in reflecting the performance of anti-slip system. Therefore, the establishment of a comprehensive evaluation method for anti-slip control is necessary.