1.1 Technical background

Birds are human friends, and while humans take care of them, they are also troubled by them. For example, birds building nests and defecating on power transmission towers can be a headache inducing problem. In order to improve the reliability and safety of power transmission and transformation equipment, and avoid faults such as ground discharge caused by bird nesting, it is necessary to take measures to drive away birds without harming them. The current bird repellents used in power transmission and transformation equipment mainly include windmill type bird repellents, voice bird repellents, high-voltage electronic pulse electronic bird repellents, capacitor discharge induced air explosions, strong light bird repellents, and anti bird stings.

(1) The windmill type bird repellent is the earliest bird repellent to enter the market. Its principle is to rotate the wind bowl on the bird repellent to intimidate the bird under the action of the wind. The characteristic is low price, but it is prone to aging, cannot function when there is no wind, and birds are easy to adapt.

(2) Voice bird repellent is a bird repellent device made using voice chips or MP3 technology. Play pre recorded bird cries and the calls of bird predators to scare birds. The characteristic is that it has an explosive bird repellent effect, but due to the large number of bird species and the limited number of species in the domestic bird voice database, the adaptation period of birds is short; The voice bird repellent has high power and short service life. When used in power transmission and transformation units, it can also cause noise pollution. This type of bird repellent is used in airports, fruit trees, forest farms, or aquaculture.

(3) High voltage electronic pulse bird repellent device uses high-voltage discharge to shock birds and has a certain bird repellent effect. However, its bird repellent range is extremely limited, and only when the bird lands on its polar plate can it function. Moreover, its service life is short and it can cause harm to birds. When used for iron towers in power transmission and transformation units, it brings inconvenience and safety hazards to the maintenance of upper and lower iron towers. The use of bird repellent stingers also poses similar safety hazards.

(4) Capacitor discharge generates air bursts and strong light to drive away birds. It has a certain bird repellent effect, but its bird repellent range is small, and strong light is also limited by its angle. Due to the high instantaneous current, the service life is short.

1.2 Energy supply of ultrasonic bird repellent system: In order to meet the needs of energy conservation, solar photovoltaic circuit boards are used to provide electricity to the entire system. The power supply system is divided into two parts: one is an instant power supply system, which provides electricity to it through solar panels; The second is to design an energy storage circuit that stores the electrical energy converted from solar energy through a battery for use on cloudy days and at night. Clock circuit: Design a circuit through programming that can control the transmission cycle and adjust the transmission cycle as needed. Photosensitive induction circuit: The photosensitive induction circuit composed of photosensitive components is used to achieve reasonable utilization of electrical energy. When at night or on cloudy days, the light is collected by photosensitive sensors and automatically adjusted to energy-saving mode. Ultrasonic emission circuit: A frequency adjustable sound wave transmitter is designed based on the ultrasonic emission circuit, and users can adjust the emission frequency of sound waves according to the driven object. Users can adjust the frequency of sound waves through an external frequency adjustment button. The correct response to the button is achieved through a diode indicating circuit. Main control circuit: Design the main control circuit using C8051F310 to achieve signal acquisition and command issuance, control the frequency of sound wave transmission, and achieve optimal system operation mode.

Finally, connect each part of the circuit with the main control circuit to achieve the overall function of the machine. 1.3 Specific Implementation Methods Power Supply Introduction: We plan to use two power supply methods for power supply: 1) Battery method. This design uses a 6V power supply to power the system, which has strong current driving ability and stable voltage output performance. The battery has a small size and a relatively low price. 2) Solar panels are relatively expensive, so we did not use them in our design. But it is more suitable for outdoor use, and there is no need to consider the battery level, so we only have an interface that can be added when needed.

3) Power protection is added to prevent the reverse connection of the positive and negative poles of the power supply from burning out the components of the circuit, mainly achieved through the diodes in the diagram. When the power supply is reversed, the diode will conduct before the switch closes. Without a current limiting resistor, the current after conducting is large enough to burn out the diode. 4) The smoke from burning is enough to catch everyone's attention. But this circuit cannot fully guarantee the protection of the power supply. When the diode is burned out, the PN junction of the diode is damaged, and the entire tube shortens the switch like a wire, with the same effect as closing the switch, causing further damage to the subsequent circuit. So when you notice any signs of emitting light or heating from the diode, you should immediately disconnect the power supply to avoid burning out the subsequent circuit. The stabilizing circuit power supply stabilizes the voltage to 5V through 1084, and then stabilizes the voltage through LM117. 3.3V is used to power the microcontroller, and 5V is used to drive the ultrasonic generation circuit.