How to calculate the configuration of solar street lamp? Since solar street lamps rely on the sun to generate electricity, we need to know how to calculate. I start with how much electricity solar street lamps use every night. Only when we know the electricity consumption every night, we can calculate how much electricity we need to generate every day.
Case: In the process of beautiful village construction in the middle and lower reaches of the Yangtze River (peak sunshine 4H), install 30W LED light source and turn on the light for 7 hours every night to ensure that the light is normally on 3-4 rainy days;
We first calculate the power consumption required by this configuration: 30W LED light source, solar street lamp, normally make 12V system, from which we can get 30W current, 30W/12V= 2.5a current, now the power consumption every night is 2.5a *7H= 17.5ah; If there is no sun to ensure that 3 to 4 rainy days normal light, the size of the battery is 17.5AH*4=70AH;
But due to the existence of solar street lamp battery overcharge and overrelease protection, the normal solar street lamp battery charging depth is 90%, discharge depth is 70%, that is to say 70AH configuration is 70% of the total configuration, the real capacity of the battery =70AH/0.7=100AH;
In order to meet the daily power consumption of the panel, the panel must generate more than or equal to the power consumption. We assume that the wattage of the battery is X, X/17.5V(17.5V represents the working voltage of the 12V panel)= working current, X/17.5V*4H(effective illumination time)= 17.5ah, From this, we can infer the size of the required solar panel X=76.56W;
However, due to the existence of line loss and controller loss in the solar street lamp system, the normal loss is about 5%-25%, that is, in the process of configuring the panel, the normal loss is calculated according to 20%, and the real size of the panel X can be calculated as X=76.56W*(1+0.2)=92W; Solar controller configuration, 30W LED discharge current is 2.5a, charging current is 92W/17.5V= 5.2a;
So when choosing the controller can choose within 10 a, kaiyuan lighting group 3 a controller electricity current of 5 a, charging current is 10 a it compared with, if you configure 10 a controller, actually don't need, the size of the controller can be as long as more than the current generation and recharge, so in the process of configuration controller is not the bigger the better.
