hidden elo and lp

Well before the season ends i just wanted to know how does our mmr correspond with how much lp we get. I am wondering this because ive just recently got a 7 win streak on ranked but i didnt see an incline with my lp right now im usually getting 15 average and 20 after i lose like once or twice. but ive noticed im no longer being matched with bronze 1 or 2. does anyone understand the system enough to explain this to me?