中文摘要：

本文针对三维直角坐标转换中7参数量纲不同的问题，设计了“变更求解参数以使形式误差基本相当”的求解模式，有效改善了小参数情况下法方程的条件，并提高了大参数情况下参数解的稳定性。针对大旋转角情况，设计了简洁有效的迭代求解模式，便于模块化编程，并具有收敛快、参数初值动态范围广的特点。针对大平移，采取了预先部分扣除的方式，获得了稳定的参数解。算例验证了这些处理方式的有效性。

英文摘要：

The issue of different dimensions of parameters in the transformation of 3D Cartesian coordinates was proposed to be treated by adjusting the solving parameters in order to let the formal errors be on the same level of magnitude, which improved the condition of the normal equation and maintains the stability of solutions both for cases of small and large parameters. Concerning large rotations, a compact and effective iteration solution mode was developed, which was convenient for programming, sustained a rapid convergence of solutions and held a wide dynamical range of initial values of parameters. The large translation was proposed to be preliminarily partially deducted in order to improve the stability of solutions. The effectiveness of the proposed measures was confirmed by checking computations.