Solar street lamps controller tracking principle

Existing solar energy automatic tracking controller outside two kinds: one is to use a light sensor and the Schmitt trigger or monostable trigger, a light-activated Schmitt trigger or optical monostable trigger to control the motor stopped, turned; 2 it is to use two light

the existing solar energy automatic tracking controller outside two kinds: one is to use a light sensor with Schmitt trigger or monostable trigger, a light-activated Schmitt trigger or optical monostable trigger to control the motor stopped, turned; The second is to use two photosensitive sensor and two comparator respectively two optical comparator control motor and reversing. Because of all the year round, and the strength of the ambient light and the sun at noon in the morning and evening change range is very large, so the above two kinds of controller is very difficult to make the sun can receive four seasons all-weather track the sun. Control circuit described here also includes two voltage comparator, but in its input the photosensitive sensor respectively by two photosensitive resistance in series cross combination. Each group two photosensitive resistance of a bias resistors for the comparator, the other for bias resistors; A detection of the sun and the other is testing environment light and sent to the comparator input side comparison level is always equal to the difference of the light. So, this controller can make the solar receiver all-weather track the sun of the four seasons, and debugging is simple, the cost is low. Principle

circuit schematic circuit diagram is shown in figure 1, double op-amp LM358 and R1, R2, constitute two voltage comparator, reference voltage to VDD ( + 12 v) The 1/2. Photoresistance RT1, RT3 RT2 potentiometer RP1 and photosensitive resistance, RT4 and potentiometer RP2 respectively photosensitive sensor circuit, the circuit is special in can be compensated automatically according to the strength of the ambient light. As shown in figure 2, install the RT1 and RT3 on one side of the vertical visor RT4 and RT2 mounted on the other side. When RT1, RT2, RT3 and RT4 natural light on the conditions at the same time, the RP1 and the center of the RP2 voltage constant. If only RT1, RT3 under the sun, RT1 resistance decreases, and (3) feet of LM358 potential rise, output high level 1 foot, triode VT1 saturation conduction, relay K1 conduction, convert contact 3 and 1 closed contact. RT3 impedance decreases at the same time, LM358 potential drop 5 feet, K2 is not action, LED street light, the switch contacts closed and static contact 2, 3 M motor forward; Likewise, if only RT2, RT4 under the sun, relay K2 conduction, K1 disconnect, M motor reversal. When transferred to the vertical visor on either side of the light phase at the same time, the following by K1 and K2 conduction, motor M to a halt. In the sun constantly in the process of migration, the strength of the light on both sides of the vertical visor constantly change alternately, motor M - — Stop, turn - — Stop, make solar receivers are always facing the sun. Four photosensitive resistance that has the advantage of cross arrangement: ( l） LM358 potential rise (3 feet, 5 feet potential is lower, LM358 potential rise (5 feet, (3) feet potential is lower, can make the motor and reversing work is simply and reliable; （ 2) Can be directly used to install circuit board shell as vertical visor, to avoid the photoresistor RT2, leads to RT3 shade all trouble.

use of the device, don't have to worry about whether it can automatically return next morning. The sun rises in the morning, on either side of the vertical visor light can't be exactly equal, so, the control circuit can control the motor, and the drive mechanism to the receiving device to the east, until solar receivers on the sun.

installation and debugging of the whole solar receiver structure is shown in figure 2. As vertical visor case it is best to use no reflection of deep color material, the parameters of the four photosensitive resistance requirement is consistent, namely, bright, dark resistance equal to and a linear change. When installation, four photosensitive resistance do not bulge on the surface of the shell and the best concave point, so as to avoid scattering sunlight interference; Vertical visor ( The control box) At the edge of the receiver, both can rotates and is not affected by the reflected light of the strong light. Conditioning test, first of all, don't let the sun directly according to the four photosensitive resistance, and then adjust the RP1, RI2, LM358 two on positive input the equal potential and reverse input end is higher than 0. 5V－1V。 After the debugging, let the sun to the vertical visor, receiving device can automatically track the sun.