[项目二——手动降压启动2.ppt

Y-?降压启动控制线路 工作原理 前 沿 联系之前学过的电动机的定子绕组的连接方法，学习掌握Y-?降压启动的工作原理。 工作原理 Y-Δ换接启动就是电动机在启动时把定子绕组连成星形，等到转速接近额定值时再换接成三角形连接。这样，降压启动时电流仅为直接启动时的三分之一。必须指出，这种启动方法只适用于正常运行时定子绕组为三角形联结的电动机。 原理图： 工作原理 合上组合开关QS Y形启动： 按SB2 ?形运行： 按SB3 停止： 按下SB1——KM1、KM3线圈失电——电动机停转 作业： 完成实训报告 * * Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. KM1线圈得电 KM2线圈得电 常闭先打开——KM2线圈 失电 常开后闭合——KM3线圈得电 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.