The Design Of A Bird Repeller Utilizing Varying Frequency Ultrasonic Noises With Intermittent Power Supply From Railway Lines

Since reform and opening up, with the rapid development of economy, the electric railway system in our country is being lager and lager than ever. As a result, the corresponding security issues are receiving increasing attention, such as, in the spring, the transmission line of railway system trips frequently. Maybe there are many reasons for this phenomenon, but the birds disaster should be the leading one. The repelling devices used in railway system are mainly a kind of windmill repellers. As these devices cannot physically hurt the birds, so the birds can soon accustom to them, and the effect is not ideal too. Thus, a new kind of safe and more effective repeller is much-needed.According to some papers, if keep birds in a loud ultrasonic circumstance ling time, it can seriously hurt their nervous system, even make then death. So after utilizing the special structure of railway power supply system, this phenomenon can be used to repel birds in railway system, as a kind of ultrasonic birds repeller designed in this paper. It has several distinguishing features, to begin with, getting and storing electricity from intermittent current circuit. After getting electricity through a current transformer coil form the return line or protect line, which has large current and earth potential when a train is passing by, the energy is stored in the super capacitors, in order to provide a reliable power to the load, no matter whether a train is in supply arm or not. Secondly, it is surge current and voltage protection, in order to avoid the surge current when the train starts and the supply arm is struck by lightning or grounded. In this paper, the designers make the capacitor voltage balancing circuit and the leakage circuit into one, so the electronic components protection is simply and reliably achieved. Last but not the least, it should be the frequency constant-changing ultrasonic output capability. The cheap but not inefficient MCU STC10F08XE is used here to generate17-35kHz sinusoidal wave signal in several mode, as frequency sweep mode, frequency random mode, varying amplitudes in single frequency mode, etc.Last, in the output effect test stage, in order to avoid the human’s influence to keep the scientificalness and intuitive of results, the designers find the best experimental subjects:pigeons in the public squares. Moreover the costs of experiment and time consumption in comparative experiment are all sharply reduced. After experiment, the output of birds repeller is checked up, and the processes of repelling birds and abating their adaptability are clear, meanwhile, feedback is reconsidered in the next design stage.