I am designing a circuit to drive a high power LED system. The system has to drive max. 7 LED strips, each strip has 20 LEDs, each LED is about 3W (forward voltage 3V, 1A). As such, I have drafted two solutions.
For the first solution, please see the attached picture (solution-1.png). I have designed to include a simple constant current source circuit on each LED strip, such as a LM317, to provide the 1A current for each strip. For the power supply, I want to use a AC/DC switching power supply to provide at least 450W, 75V output.
I would like to ask is this system feasible? One of my concern is that can I find an off-the-shelf AC/DC switching power supply to output ~75V, 450W? If not, what is your suggestion?
Another question is if this is feasible, is the LM317 good to be a constant current source in this circuit?
For the second solution, please see attached picture (solution-2.png). In this solution, each LED strip is connected with a off-the-shelf AC/DC constant current source. Therefore 7 strip will need 7 source. This will be rather bulky.
Also, is this system feasible? To switch on/off the LEDs by a micro-controller, I will need to use a solid-state-relay to switch the AC power of the strip, I am not sure if this will has any problem because the load (the constant-current-supply and the LED strips) is not a linear load. (I am not switching a PWM signal, I only need to switch a very low speed on and off sequence).
In your opinion, which solution is better? What is their pros and cons?
Thank you very much for your help!