∵∠ABC+∠ACB+∠BAC=180°
又∵O是△ABC的角平分线的交点
∴∠OAB+∠OBA+∠OCD=90°
∵∠OCD=30°
∴∠OAB+∠OBA=60°
∵∠BOD=∠OAB+∠OBA
∴∠BOD=60°