施耐德140系列140XTS00203 Quantum

140XTS00203 Quantum

功率器件在静止变频技术中的应用主要有三个方面：首先，功率器件可以用来控制电机的转速，从而实现变频控制；其次，功率器件可以用来控制电机的功率，从而实现节能控制；后，功率器件可以用来控制电机的转矩，从而实现控制。此外，功率器件还可以用来控制电机的启动和停止，从而实现控制。

　　变频调速技术的发展

　　上世纪50 年代末，由于晶闸管（SCR）的研究成功，电力电子器件开始运用于工业生产，可控整流直流调速便成了调速系统中的主力军。但由于直流电机结构复杂，造价比交流电机高，直流电动机在运行中，炭刷接触产生炭粉而易引起环火，须经常维护，而且直流调速系统线路复杂，维修十分不便。因而便了各国对交流调速技术的开发和研制。

　　20 世纪80年代中期，随着第三代电力电子器件，如门极可关断晶闸管（GTO）、大功率晶体管（GTR）、绝缘栅双极型晶体管（IGBT）等全控型电力电子器件的研制成功，以及电力电子器件从电流驱动型到电压驱动型全控器件等的发展，日本等国已先后研制开发出了功率等级不同的把控制、驱动、检测、保护及功率输出集于一体的变频调速产品，如图1所示。从而使交流变频调速的关键装置———逆变器性能优良，主电路简单，驱动方便，工作可靠。同时随着控制理论、微电子技术和计算机技术的发展，使交流电机变频调速技术取得了突破性进展，并以其的调速性能和良好的节能效果逐渐取代了直流调速系统和其他的调速方式，如变极调速、串级调速、滑差电机调速、整流子电机调速等。

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