美国加州国家半导体公司最近推出一种新型芯片,防止应用计算机的产品遭受危害。新型芯片为集成电路(IC),能监测温度、电压、风扇速度等变量,能分析数字位流,对即将发生的故障显示报警。该芯片的主要构件为:带可编程极限寄存器的集成式...美国加州国家半导体公司最近推出一种新型芯片,防止应用计算机的产品遭受危害。新型芯片为集成电路(IC),能监测温度、电压、风扇速度等变量,能分析数字位流,对即将发生的故障显示报警。该芯片的主要构件为:带可编程极限寄存器的集成式温度传感器(可精确到±3℃);远距离温度传感 IC 用界面;7种电压输入及其相关的监视寄存器;3种风扇输入,其中2种为可编程(1100～8800rpm),另一种为固定程序(4400rpm);一个具有7通道的多路输入;展开更多
This paper presents an electronic VSD （variable speed drive） for three-phase IM （induction motor） using a microcontroller. The VSD is designed for cooling applications where the 1M is coupled to a cooling fan. The...This paper presents an electronic VSD （variable speed drive） for three-phase IM （induction motor） using a microcontroller. The VSD is designed for cooling applications where the 1M is coupled to a cooling fan. The drive receives temperature feedback from objects to be cooled and output a corresponding frequency to the IM. A prototype of the VSD is constructed to control a 175 W, four pole, squirrel cage three-phase IM. The heart of the control circuit is a low-cost microchip＇s PICI6F777 microcontroller which is programmed using C language to generate variable frequency SPWM （sinusoidal pulse width modulation） switching signals. These switching signals are fed to an 1GBT inverter. The VSD constructed can be switched between two modes of speed control＂ automatic temperature-controlled mode and manual user-controlled mode. Cost savings using the prototype are demonstrated.展开更多
文摘美国加州国家半导体公司最近推出一种新型芯片,防止应用计算机的产品遭受危害。新型芯片为集成电路(IC),能监测温度、电压、风扇速度等变量,能分析数字位流,对即将发生的故障显示报警。该芯片的主要构件为:带可编程极限寄存器的集成式温度传感器(可精确到±3℃);远距离温度传感 IC 用界面;7种电压输入及其相关的监视寄存器;3种风扇输入,其中2种为可编程(1100～8800rpm),另一种为固定程序(4400rpm);一个具有7通道的多路输入;
文摘This paper presents an electronic VSD （variable speed drive） for three-phase IM （induction motor） using a microcontroller. The VSD is designed for cooling applications where the 1M is coupled to a cooling fan. The drive receives temperature feedback from objects to be cooled and output a corresponding frequency to the IM. A prototype of the VSD is constructed to control a 175 W, four pole, squirrel cage three-phase IM. The heart of the control circuit is a low-cost microchip＇s PICI6F777 microcontroller which is programmed using C language to generate variable frequency SPWM （sinusoidal pulse width modulation） switching signals. These switching signals are fed to an 1GBT inverter. The VSD constructed can be switched between two modes of speed control＂ automatic temperature-controlled mode and manual user-controlled mode. Cost savings using the prototype are demonstrated.
