5SHX1445H0001 ABB ICGT模块 PLC模块卡件 变频器 伺服控制器

5SHX1445H0001 ABB ICGT模块 PLC模块卡件 变频器 伺服控制器

5SHX1445H0001 ABB ICGT模块 PLC模块卡件 变频器 伺服控制器

可控硅（Silicon Controlled Recfier） 简称SCR，是一种大功率电器元件，也称晶闸管。它具有体积小、效率高、寿命长等优点。在自动控制系统中，可作为大功率驱动器件，实现用小功率控件控制大功率设备。它在交直流电机调速系统、调功系统及随动系统中得到了广泛的应用。

可控硅分单向可控硅和双向可控硅两种。双向可控硅也叫三端双向可控硅，简称TRIAC。双向可控硅在结构上相当于两个单向可控硅反向连接，这种可控硅具有双向导通功能。其通断状态由控制极G决定。在控制极G上加正脉冲（或负脉冲）可使其正向（或反向）导通。这种装置的优点是控制电路简单，没有反向耐压问题，因此特别适合做交流无触点开关使用。

可控硅是P1N1P2N2四层三端结构元件，共有三个PN结，分析原理时，可以把它看作由一个PNP管和一个NPN管所组成，其等效图解如右图所示。双向可控硅：双向可控硅是一种硅可控整流器件，也称作双向晶闸管。这种器件在电路中能够实现交流电的无触点控制，以小电流控制大电流，具有无火花、动作快、寿命长、可靠性高以及简化电路结构等优点。从外表上看，双向可控硅和普通可控硅很相似，也有三个电极。

但是，它除了其中一个电极G仍叫做控制极外，另外两个电极通常却不再叫做阳极和阴极，而统称为主电极Tl和T2。它的符号也和普通可控硅不同，是把两个可控硅反接在一起画成的，如图2所示。它的型号，在我国一般用“3CTS”或“KS”表示；国外的资料也有用“TRIAC”来表示的。双向可控硅的规格、型号、外形以及电极引脚排列依生产厂家不同而有所不同，但其电极引脚多数是按T1、T2、G的顾序从左至右排列（观察时，电极引脚向下，面对标有字符的一面）。

5SHX1445H0001 ABB ICGT模块 PLC模块卡件 变频器 伺服控制器

Silicon Controlled Recfier (SCR) is a high-power electrical component, also known as a thyristor. It has the advantages of small size, high efficiency and long life. In the automatic control system, it can be used as a high-power driving device to realize the control of high-power equipment with low-power control. It has been widely used in AC and DC motor speed control system, power regulation system and servo system.

Thyristors are divided into two kinds: unidirectional thyristors and bidirectional thyristors. Bidirectional thyristor is also called TRIAC, or TRIAC for short. The bidirectional thyristor is structurally equivalent to two unidirectional thyristors in reverse connection, and this thyristor has a dual pilot pass function. Its on-off state is determined by the control pole G. Adding a positive pulse (or negative pulse) to the control pole G can make it forward (or reverse) conduction. The advantage of this device is that the control circuit is simple and there is no reverse voltage problem, so it is particularly suitable for AC contactless switch use.

The thyristor is a P1N1P2N2 four-layer three-terminal structural element with a total of three PN junctions. When analyzing the principle, it can be regarded as composed of a PNP tube and an NPN tube, and its equivalent diagram is shown in the figure on the right. Bidirectional thyristor: Bidirectional thyristor is a silicon controllable rectifier device, also known as bidirectional thyristor. This device can realize the contactless control of alternating current in the circuit, and control the large current with small current. It has the advantages of no spark, fast action, long life, high reliability and simplified circuit structure. From the appearance, the bidirectional thyristor is very similar to the ordinary thyristor, and also has three electrodes.

However, in addition to one of the electrodes G is still called the control pole, the other two electrodes are usually no longer called the anode and cathode, but collectively referred to as the main electrode Tl and T2. Its symbol is also different from ordinary thyristors, which is drawn by connecting two thyristors together, as shown in Figure 2. Its model is commonly used in our country as "3CTS" or "KS"; Foreign data are also represented by "TRIAC". The specifications, models, shapes and electrode pin arrangement of bidirectional SCR vary according to the manufacturer, but most of its electrode pins are arranged from left to right in the order of T1, T2, G (when observed, the electrode pins are down, facing the side marked with characters).