基于低成本单片机的相量测量单元提高智能电网可靠性

　　基于低成本单片机的相量测量单元提高智能电网可靠性

　　8月14日，安大略和美国东北部八个国家的2003， 50万人失去了电力。一个炎热的下午和克利夫兰附近一座燃煤发电站意外的破裂，引发了连锁反应，在94分钟内，美国东北部大部分地区都陷入了黑暗之中。花了24个多小时才恢复了电网大部分地区的电力，完全恢复了满足该地区需求的生产能力，几乎花了两周时间。它将永远被铭记为2003的大停电。

　　令大多数电网运营商吃惊的是，一场看似无辜的事件可能会导致整个电网崩溃。当输电线路接近最大容量时，克利夫兰的一个局势被允许超过90分钟未被发现。炎热的夏季空气对该地区的空调产生了巨大的电能需求。当燃煤发电站脱机时，当地输电线路超载，导致线路延伸并向地面下沉。当线路接触到允许在传输线下面生长的树时，线路短路到地面，导致自动电路保护中断。这就给剩余的线带来了更多的压力。一个小时后，其他三条线路失灵，俄亥俄电力公司的剩余电力线路也出现了灾难性的浪涌，引发了其他几条线路断路器。由于剩余的输电线路没有足够的能力携带整个区域所需的能量，整个电网在90秒内倒塌。这家电厂关闭了。由于无法提供所产生的能源，一些核电站被迫执行紧急程序，关闭核反应堆。这是一个对核反应堆造成损害的程序。在电网上恢复电力几乎花了四天时间，近两周时间才使所有反应堆恢复满负荷运转。

　　An investigation of The Great Blackout revealed that the power grid control systems were antiquated and largely unable to monitor and protect the health of the grid. Time was never an issue. It took 31 minutes from the moment the Cleveland power station failed until the first transmission line collapsed. The situation looked manageable for another 61 minutes， until more transmission lines started burning out. The men and women controlling the grid were caught completely off guard because they had no means to detect warning signals from the power grid. Without access to real time information， the power grid control rooms were unable to predict where the next error would occur and plan corrective actions. The investigation concluded that the disaster could have been avoided if the power grid had been equipped with better monitoring systems. The U.S. Department of Energy considers the US-Canada blackout in 2003 to be the single most important motivator behind the Smart Grid initiative.