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Intercity train is a short distance train used for transportation between city and surrounding areas. Compared with other types of EMUs, it has higher pantograph lifting frequency. In this paper, based on Simulink platform, the transient overvoltage generated in the process of intercity train pantograph lifting is simulated, and the voltage waveform in the process of intercity train pantograph lifting is measured at Tongling station of Wenzhou rail transit line S1, which verifies the accuracy of the simulation results.

The paper proposes a coupling probe which can effectively expand the coupling adjustment range, and optimally designs a 64-element array antenna’s rectangular radial line feed network at the center frequency of 2.1 GHz. Simulation results show that the feed network whose caliber is 744 mm×744 mm can achieve approximately 64-road equiamplitude feed. The reflection coefficient is less than 0.1 at the center frequency, and less than 0.2 in the frequency band ranging from 2.06 GHz to 2.15 GHz.

In order to optimize the open loop control strategy of stepper motor, the velocity profiles of stepper motor were studied. There are three widespread used velocity profiles: trapezoidal, parabolic, and S-curve profiles. In this paper, trapezoidal velocity profile was chosen for further study. In order to accurately generate an arbitrary trapezoidal velocity profile, a new velocity profile generation methodology is developed. It shows how to deal with computational complexity and balance performance against resources requirements using field programmable gate field (FPGA). Thus, a high performance stepper motor controller can be achieved by combining a system on a chip (SOC) with this hardware. Experimental results verify the accuracy and efficiency of the proposed approaches.

This paper aimed at the features of the array antenna that with large number units, short work cycle, complex electromagnetic environment and high stability requirement, designed the master control system which based on the VxWorks real-time operating system. The master control system as a whole array antenna control center needed to connect multiple subsystems. After a full investigation, the paper proposed the following scheme: used the Ethernet port for the remote control and received status information feedback, RS485 serial port to receive external data, set up the CAN network to connect the slave machines, to achieve the control of the array antenna.

A special Controller Area Network (CAN) bus application layer protocol is designed for the high reliable and high real-time control network of the beam control system. In this paper, messages on the network are classified and the identifier coding, data coding, network management mechanism and physical interface are defined. Then network load analysis for the real-time control network is introduced. At last a test platform based on CAN bus for the beam control system is built to validate the design. Experiment results indicate that the developed CAN control network for the beam control system is very reliable and has good real-time performance and low network load rate.