Question: My 3 year old doesn't go to sleep until late after 11pm and wakes up by 7.30am. Is this ok? She sleeps for 2 to 3 hours in the afternoon until 5pm.

Since birth she hasn't slept properly.

Answer: 
I completely agree with @Nilah's answer. 11 to 15 hours of sleep is normal for a child her age.

Physically draining activities are usually the best for getting a child into a normal sleep pattern. For example, my daughter is 4; I wake her up as I get ready for work at 7am. As soon as she gets up, I make her breakfast, sit her at the table and let her eat while I finish getting ready. By 7:30am she is done with breakfast and heading into the garage to play with her toys. By 11am she's eating lunch and then her and her brother go into the backyard with my wife to run around and play. They don't come back inside for at least an hour. She eats dinner at 5pm, bath at 6, and in bed by 7:30pm; I let her play in her room or watch her T.V. if she wants, but it's lights out by 8pm and she's going to sleep, usually she's out cold on her own around 7:45pm.

That nap in the afternoon is one of the biggest issues keeping her up until 11pm. If she doesn't take a nap so late, or doesn't take one at all, and she's physically exhausted from playing all day, she will go to bed at what we as adults consider a decent hour.
At the age of three a child rapidly grows and the best time of growing a child is during deep sleep. Sleeping 11 to 15 hours daily is the best cycle for three ager. However I have few suggestion which increase a child sleeping hours.
1 diet having solid ingredients
2 drinking of milk at least 250 ml milk before sleep at night
3. Involve in physical activities in evening 
4. Avoid him to spent more time in front of tv, laptop or cell phone.