煤矿直流供配电线路故障电流具有幅值大、上升率高的特征，是威胁供电系统安全稳定的重要因素。利用直流配电系统电气特征实现故障识别的方法较少考虑保护设备的实际情况，难以处理设备误差及扰动，不满足继电保护的可靠性要求；而基于电力电子变换器的主动保护方法则较少利用故障电气量信息，仅依靠设备动作特性实现故障切除，往往不能满足继电保护的速动性要求。针对上述问题，提出一种基于暂态电流导数的煤矿直流配电线路无通道保护方案。将直流侧并联电容放电电流的二阶导数作为保护加速判据，若满足加速判据则启动加速动作，若不满足加速判据则按照断路器既定延时动作。故障发生时，电流均指向故障点，则可利用功率流向的变化初步判断故障方向，构成无通道保护，使故障线路两端断路器加速跳开，从而缩短故障切除时间。仿真结果表明，在不同故障发生位置、过渡电阻及故障类型条件下，若加速动作能够有效启动，则基于暂态电流导数的煤矿直流配电线路无通道保护方案可快速切除故障，减少故障时间；若加速动作不能启动，保护方案也能按照既定延时配合实现故障类型和区段的确定并切除故障。

The fault current of coal mine DC power supply and distribution lines has the features of large amplitude and high rise rate, which is an important factor threatening the safety and stability of the power supply system. The method of using electrical features of DC distribution systems to achieve fault recognition rarely considers the actual situation of protective equipment. It makes it difficult to handle equipment errors and disturbances, and it does not meet the reliability requirements of relay protection. The active protection methods based on power electronic converters rarely utilize fault electrical information and rely solely on equipment action features to achieve fault removal. It often fails to meet the quick action requirements of relay protection. In order to solve the above problems, a non-communication protection scheme for coal mine DC distribution lines based on transient current derivation is proposed. The second derivative of the discharge current of the parallel capacitor on the DC side is used as the protection acceleration criterion. If the acceleration criterion is met, it will start the acceleration action. If the acceleration criterion is not met, it will act according to the established delay of the circuit breaker. When a fault occurs, the current is directed towards the fault point. The change in power flow direction can be used to preliminarily determine the direction of the fault, forming a non-communication protection. It will accelerate the tripping of the circuit breakers at both ends of the fault line, thereby shortening the fault removal time. The simulation results show that under different fault positions, transition resistors, and fault types, if the acceleration action can effectively start, the non-communication protection scheme of coal mine DC distribution lines based on transient current derivation can quickly remove faults and reduce fault time. If the acceleration action cannot be started, the protection scheme can also cooperate with the established delay to determine the fault type and section and remove the fault.