OCP或SCP–这是个问题！

　　OCP或SCP–这是个问题！

　　通常情况下，许多不同类型的保护功率晶体管，电机或任何部分的系统所需的电机驱动应用。逆变器的电流保护是至关重要的项目之一。它不仅防止功率晶体管的任何潜在的损害，但也退磁电机故障发生或控制变得不稳定的情况下。过电流保护（OCP）和短路保护（SCP）通常是类似的，但又有区别，本文将讨论的问题。

　　.OCP和SCP之间的差异

　　简单地说，短路保护是过电流保护的一部分。图1显示了不同的电流保护之间的关系。接地故障保护，ARM短路保护，相间短路保护均属于短路保护。

　　Figure 2 shows the different short-circuit modes and their current path. As illustrated in Figure 2（a）， ground fault occurs when the motor winding gets shorted to the motor frame， which is typically connected to the earth ground， or sometimes when a motor cable gets shorted to the earth ground. Figure 2（b） shows arm short which refers to the case when both the high-side IGBT and the low-side IGBT turn on accidentally at the same time and very-high current flows as a consequence. Figure 2（c） depicts a phase-to-phase short which happens when motor windings from different phases get shorted. In all three cases， the magnitude of current is limited by the impedance of its current path， including the IGBT itself.