【作者】 张国华；

【导师】 郭立炜；

【作者基本信息】 河北科技大学 ， 电机与电器， 2009， 硕士

【摘要】 自动栏杆机是应用扭矩电机控制技术和线圈式车辆检测技术于一身的自动控制设备,广泛应用于高速公路收费系统、停车场、居民小区出入口等场所。由于扭矩电机能够提供较大的启动转矩和平滑的调速特性,转矩近似与加在电机两端的定子电压成正比。利用这一特性,在扭矩电机主回路中串入双向可控硅,控制可控硅的导通角,从而控制电机端电压,驱动扭矩电机,实现栏杆机各种运动模式。要实现自动栏杆机快速平稳升降动作,栏杆臂的位置及运行速度检测至关重要。采用与驱动电机同轴连接的精密传感器取代传统的机械式限位开关,经A/D采样、微处理器处理,实现扭矩电机准确刹车、栏杆臂无磨损到位。采用逐次逼近算法,可实现栏杆机自我优化调整。工程实践中利用“地感线圈”组成震荡电路,当有金属物(汽车)经过时,由于空间介质发生变化引起振荡频率的变化,采样这一频率变化作为汽车经过“地感线圈”的证实信号,完成车辆检测。线圈式车辆检测器与自动栏杆机联动可实现车辆经过后自动落杆、“防砸车”等功能。针对ETC(不停车收费)系统要求快速栏杆机控制,本课题对采用直流无刷电机控制方式进行了初步探讨。本课题通过对自动栏杆机扭矩电机控制、自我优化调整、线圈式车辆检测器原理、实现方式、工程实践应用的研究与改进,有助于解决自动栏杆机控制、维修、应用方面相关问题,对栏杆机控制系统开发应用具有一定参考价值。更多还原

【Abstract】 A auto-barrier (also known as access toll gate) is one of the auto-control units which is based on the combination of the torque motor and vehicle loop detection technology. Recently, it has been widely used in parking lots, toll booths, security areas, access road, and so on.Torque motors are designed to provide high starting torque and sloping characteristics (torque is highest at zero speed and decreases steadily with increasing speed), and operate over a wide speed range. The torque generated by the torque motor changes approximately proportionally to the square of the voltage. This character is commonly used to control voltage by phase control using thyristors or silicon-controlled rectifiers (SCRs). When the voltage supplied to the motors is changed, speed-torque curves with a sloping characteristics shifts to that of the corresponding voltage. So, all kinds of barrier’s movement mode can be achieved.One kind of precise speed/position counters replacing the traditional mechanical limit switch is normally coupled to the shaft of the motor and provide a count to a microprocessor. The upper and lower limits are programmed into the microprocessor .As the access barrier cycles, the counter update the count to the microprocessor. Once the proper count is reached, the access barrier stops smoothly and free of metal fatigue or corrosion. Method of successive approximation is applied in self-optimization of the barrier’s adjustment.In engineering, vehicle loop detectors use a coil of wire buried in the drive way which is connected to an inductive loop detector. When a vehicle enters the loop the body and frame provide a conductive path for the magnetic field; causing a loading effect, which in turn causes the loop inductance to decrease. The decreased inductance causes the resonant frequency to increase from the nominal value. If the frequency change exceeds the threshold set by the sensitivity setting, the detector module will output a detect signal. Automatic functioning of the barrier ,such as the barrier will only close when a vehicle passed through the loop ,and the boom will be raised again when a vehicle be detected during the boom fallen time, can be achieved when the loop detector combined with the barrier control unit.According to the requirement of high speed automatic barrier used in ETC system, preliminary study on the combination of the brushless DC motor with its intelligent control mechanism has also been carried on in our task.In our task, we study the auto-control of torque motor in the access barrier, self-optimization adjustment, the theory of vehicle loop detection and its application, etc. and also we provide unique technology to improve operation performance of access barrier used in the field of ETC system. It must be helpful to solve problems on access barrier control, maintenance and fix, and application. It will also be of great value for reference for the development and research of auto-control system of access barrier.更多还原