| This paper is divided into two parts. The hardware systems of platform screen doors controller and digital signal processing system for Non-Dispersive Infra-Red Analyzer are developed in this paper. The entire paper is a summary of author’s study and work during his graduate student period. Although there are some differences in the fields of the two parts, there are also some similarities. Both of the two parts use DSC as the core, and combine with corresponding digital and analog circuits, to achieve some signal processing and control algorithms.Nowadays rail transport, such as subway and light rail, has become the most convenient mode of transportation in modern cities. The platform screen doors are mostly installed in the new rail transit projects, and play the multifaceted role of the safety, health, energy and other. However, the screen door controllers used in domestic rail transport are largely dependent on imported foreign products, although their technology is mature, but very expensive, confidential technical and difficult to maintain. Therefore, the development of domestic screen doors controller task is urgent.The hardware system of platform screen doors based on the MCU+IPM architectures is developed in the upper part of this paper. The system consists of four parts:a motor, a main circuit, a control circuit and a protection circuit. The brushless DC motors with Hall position sensor is selected because it combines the strengths of the DC motor and AC motor, simple structure, easy to control, high reliability. In the main circuit part, an Intelligent Power Module (IPM) made by Mitsubishi is used to constitute the motor drive circuit. The IPM integrates the IGBT and driver protection circuitry, which simplifies the circuit design and improves system reliability at the same time. The Infineon XE164microcontroller is chosen as the core of control circuit. This chip is optimized specifically for the motor drive, easy to control brushless DC motors simultaneously, and has advantages of high stability, strong a This system has the prospect of engineering application anti-interference ability. The optical isolation are adopted in signal transmission between the main circuit and control circuit, and overvoltage, undervoltage, overcurrent, overheating and other hardware protection measures are employed to ensure the long-term stable and reliable system operation. Screen Doors drag the experimental results show that the speed performance of the system is fine, start from a standstill to2500rpm running at full speed only needs200ms. Anti-trap performance is fast, accurate, and does not pose a threat to passengers. Screen Doors switching process is fast and smooth. This system has the prospect of engineering application.Hardware of the digital signal processing system is developed for Non-Dispersive Infra-Red (NDIR) gas analyzer in the lower half of this paper. The analog phase sensitive detection circuit is used as the signal processing circuit in traditional NDIR gas analyzer. Its structure is complex, tedious debugging, and poor stability. Its measurement accuracy is not high. The hardware platform is designed with TI’s TMS320F28335DSP as the core to solve these problems.The digital signal processing hardware platform for NDIR gas analyzer includes analog process and A/D conversion circuit, DSP, the temperature control circuit, the gas pressure compensation circuit and some communication modules. Firstly, the output signal from NDIR sensor is amplified and filtered, and then the signal is converted to digital signal by A/D converter, finally the digital signal is processed by DSP. The digital processing system simplifies the process of analog processing, enhances anti-jamming capability. Digital signal processing methods are adopted to improve the system accuracy and stability, and to simplify debug process. The temperature control module makes the sensor temperature constant and reduces the measurement result fluctuations due to temperature variation. The gas pressure is measured by the pressure compensation module, and the DSP core uses the pressure values to compensate digital processing result.4-20mA module, RS-485module and relay output module enable the system to achieve automatic calibration, remote control and other intelligent features.We have tested the hardware system and the whole system. The hardware test results show that its performance is excellent, the noise is about3uV (RMS value, less than0.3ppm), and the nonlinear error is less than0.01%.The system test results show that the acquisition, processing, correction and other performance of the system meet the design requirements, and its nonlinear error is less than0.27%. Therefore, the system can replace the traditional processing system, and has good prospects for industrial applications. |
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