This paper proposes an algorithm to obtain better results in the integrated control by reflecting the characteristics of the individual control of the front wheel and the rear wheel of tram systems. In the case of the surface transportation, which has recently been introduced, severely curved driving performance is required for the downtown. It is possible to decrease the curve radius and to improve the performance of the straight driving with the individual torque control. Therefore, the individual torque control performance of the motor is the most important point of the surface transportation. The front and rear wheels have different torque characteristics, and the length of the bogie during curve travel also affects these results. This system is more controllable than the system with 1Controller 4Motor (1C4M) in the form of 2C4M with the front and rear wheels being individually controlled, allowing more precise control because of its higher degree of freedom. Because of this individually controlled characteristic, it is possible to control more precisely in the integrated control considering the characteristics of the front wheel and the characteristics of the rear wheel. The validity of the proposed control algorithm is verified by experimental results using a small-scale bogie system.

In order to realize the tram’s low-floor structure, most of the trams that have been recently introduced adopt an independently rotating wheelset. In the case of trains driving in two regions with different gauges, an independently rotating wheelset may be applied to utilize the variable track technology. Since the independent rotation type wheelset has no rotational restraint of the left and right wheels, the difference in rotational speed between the outer and inner wheels occurs naturally during curved driving, and it is applied to railroad vehicles traveling in sharp curve sections because it smoothly drives curved driving. However, the longitudinal creep force and the lateral restoring force are weakened as the left and right rotational constraints disappear. Lack of lateral direction restoring force weakens stability while causing continuous flange contact driving or zigzag phenomenon against disturbance. Under the conditions of driving in a sharp curve, these railway vehicles generate excessive wear, noise, and lateral pressure, as well as deterioration of ride comfort and derailment. In order to overcome these drawbacks, a method has been proposed in which the torque of a motor mounted on each wheel is individually controlled to generate lateral restoring force or to improve driving performance through lateral displacement control using a yaw moment. In this paper, development using HIL (hardware in the loop) simulator was performed to check the performance and stability of the individual motor torque control technology before verifying by applying the individual motor torque control to the actual vehicle. HIL simulator were constructed by combining a real-time dynamic analysis model of a railway vehicle with a drive motor to which real individual motor control was applied. Under the conditions of driving the test track where the actual test vehicle was tested, the analysis of the driving characteristics and the control characteristics of the disturbance was performed to confirm the proposed individual motor torque control performance.

The sanding device support bracket is part of the axle box and is one of the railway vehicles parts that must withstand extremely harsh environments. Conventional welded structure type brackets were cracked at welds during operation, requiring design changes. To minimize harsh environments and manufacturing errors, this review was conducted from the design stage, and design changes were made through several trial and error. In this paper, the optimal design was derived by performing topology optimization on the model designed and manufactured through trial and error and applied to the actual vehicle. The comparison of the existing model with the empirically designed model confirmed the improvement of the optimal design using the topology optimization. The optimized design was verified by the analysis and the vibration test of IEC 61373 was satisfied. The test parts based on the optimal design were applied to the actual vehicle and the performance was verified. In the optimum design process, the shape and material as well as the weight analysis were performed and finally the brackets were designed to be light in weight and improved in strength.

In above paper [1], the figures were named incorrectly. The correctly named figures and explanations follow. Fig. 1. shows the magnetic flux density distribution of the motor. As shown in the figure, the magnetic flux densities are concentrated on the lip and bridge portions and are modified to show saturation. Fig. 2. is attached (b) to express the system more clearly. In the case of Fig. 4., the proposed algorithm is modified to more clearly represent and emphasize it. In Fig. 5, the longitudinal displacement part is added to graphically show how the information of the laser sensor is received in order to calculate the yaw angle. Fig. 6. shows the algorithm in more detail, making it easier to understand.