依据闭式液压系统的工作原理和补油原理，对某盾构主驱动闭式液压系统的发热功率和补油量进行分析和计算，推导出闭式液压系统换油量和补油量的计算公式，求解出换油系数和补油系数。计算采用整体法，将所有流出闭式液压系统的油液作为一个整体来考虑，以避免对泄漏量和热油置换量进行分类讨论和计算。从理论上证明了实际补油量够用，为补油泵的选型提供了依据。

The heating power and charging oil quantity of the closed hydraulic system of the main drive of a shield are analyzed and calculated on basis of the working principle and oil charging mechanism of the closed hydraulic system. The calculation formula for the replacing oil quantity and the charging oil quantity of the closed hydraulic system are obtained and the oil replacing coefficient and oil charging coefficient are worked out. During the calculation, the oil running out of the closed hydraulic system is regarded as an integral part, so as to avoid discussion and calculation of the quantity of the leaked oil and the quantity of the replaced oil. The theory proves that the quantity of oil charged is sufficient. The paper can provide reference for the selection of oil charging pumps in the future.