In order to arrive a new compensation mode that reduces the dependence on design experience for a zoom lens, a way for power allocation and compensation is proposed. Taking the group space as initial parameters, we can determine the corresponding power allocation and actions of each component. This method helps to reduce the difficulty of power allocation and provides different ways to find the new compensation mode. In order to test the feasibility of this method,we use a three-component zoom lens for the same target with four different moving modes.The experiment results indicate that an all-movable mode is the optimum mode and theoretical results approach this optimum.