Support reuired in selection of a LED driver

[alok1982]

I need your support in selection of a LED driver.


The LED details given below;

Power for 1 LED = 9.1W; VF =35V; IF =260mA

I want to use 40LED’s. 4 strings of 10 LED’s.

Please help me to select the LED driver i.e. what Output voltage and Output current of LED driver is needed.


Thanks in Advance.

 

[Ian Rogers]

1 LED is 9W??? Are you sure... The string of 10 maybe??

 

[alok1982]

Yes Ian. It's high wattage LED.
I had attached datasheet of LED for your reference.

 

[ronsimpson]

Power for 1 LED = 9.1W; VF =35V; IF =260mA
I want to use 40LED’s. 4 strings of 10 LED’s.

So you want a 365 watts, 350 volts, 1.04 amps, constant current power supply.
What is going to power this? Four AA batteries? LOL
110VAC at 3.5A or 220VAC at 1.8A or 12V at 35A??
This is not a simple project.

 

[alok1982]

I will use 110ac at 3.5A.

 

[ronsimpson]

do you need the LEDs isolated from the power line?
(can a human touch the LEDs) If so then they need isolated.
If the LEDs are insulated from a human then we can leave them connected to the power line.

Here is a 150 watt design. About 1/2 what you want. It is easy to change the output voltage/current to match what you want. It is not easy to move it to 300 watts. But this should give you some idea of how big this project is.
https://led-driver.power.com/sites/default/files/PDFFiles/rdr292.pdf

 

[alok1982]

I am planning to use readily available LED driver to drive these LED's.

As per my requirement;
I want to use 40LED’s. 4 strings of 10 LED’s.

As per calculation;
o/p W = 365 watts, o/p V = 350 volts, o/p A = 1.04 amps

Now my queries is;
1) Which type of LED driver do I select; Constant Current or Constant Voltage? I am using 4 strings in parallel in which each string has 10 LED connected in series.
2) If I opt for Constant Current LED driver then I have to use current control resistor in each string?
3) As we know 365W LED driver is very hard to get in market, can i opt to go parallel connection of LED driver? i.e. 180W parallel 180W.
Parallel Connection diagram is in attached file.

 

[Les Jones]

It would be better using 4 constant current drivers. One for each string of 10 LEDs. What is your reason for configuring them as 4 strings of 10 ? It may be easier to find suitable drivers if you used a different configuration.

Les.

 

[alec_t]

Constant current drivers which can provide at least 70V at 260mA seem readily available. But you would be able to have only 2 LEDs per string, hence need 20 drivers .

 

[Ian Rogers]

alec_t Post #3

There are 12 led's in series inside the unit!!

 

[alec_t]

I realise that, since OP states "1 LED = 9.1W; VF =35V". So, two of those 'LEDs' is what I was referring to.

 

[ronsimpson]

The reason I brought up PFC (Power Factor Correction) back in post #6 is that with a bulb this large, 300w, much of the world will require PFC. If you are just building for your use then PFC does not matter. This choice needs to be made now. Yes/No for PFC.

There are two different directions for the driver: isolated or not isolated. This choice need to be made now.

Back in post #8 the idea came up to treat this as 4 small bulbs with 4 drivers. This will make it a more simple job. Not as good for high volume production. I probably can find many designs that are that size.

Parallel LEDs is not usually done. In the factory we sort the LEDs to get the same forward voltage. Look at the data sheet and you will see how large a range the voltage can be. (usually the minimum is not stated)

You want constant current not constant voltage. or constant power.

 

[alok1982]

So, I will use Constant Current LED driver.

PFC circuit is inbuilt in my LED driver.

Also, it's isolated design.

 

[ronsimpson]

PFC circuit is inbuilt in my LED driver.

What driver did you choose.