If you are not a UK National and do not have indefinite leave to remain in the UK, you legal rights may be more limited. You do however have the right to live free from domestic abuse and have the same rights to protection from the law as everyone else. Your partner is subject to the same sanctions. If you and your children are being hurt or frightened by your partner contact the police.
There are other people who can give you advice:-
Ethnic Minority Law Centre, Hemat Gryffe Womens Aid, Scottish Refugee Council and/or the Immigration and Advisory Service (see Useful Contacts)