Based on the Matrix theory,this article gives several controllable judgements of linear dynamic system,and tries to find out the variable which makes the system incontrollable.

• 利用矩阵理论，对线性动态系统的可控性条件作了讨论，并通过矩阵变换的结果设法确定影响系统可控性的状态变量，因而在具体的系统控制中有一定应用价值。