advice on leaving abusive partner with kids

Tay • Single mummy
Hello. Looking for advice on something
I'm leaving well, left my abusive partner who was emotionally abusive towards me. I'd like to cut all contact and I am moving away where he won't know where I am but! We do have two kids and as much as he is a asshole he is a good dad and I can't do that to my children by keeping them from him. So what do I do? 
A idea I had was instead of changing my number I would keep my number that he has and put it in a old phone and get a new number and put that new number in my current phone so he could still contact me to see the children and to arrange for me to bring them to his house ? Any other ideas for me are welcomed