什么是门关闭晶闸管及其工作

A solid-state半导体器件就像晶闸管一样不是完全受控的开关。可以这样做的操作,可以这样做,它可以通过栅极端子接通,但是不能使用栅极终端关闭。当晶闸管开关打开时,即使我们拆下栅极脉冲,它也不会关闭。所以没有控制停用thyristor转变。一旦主电流被中断,则开关将关闭。因此,无论主电源都不会破坏,难以在施加中使用。喜欢DC-AC和DC-DC电路的转换。必须使用昂贵的,以及庞大的通信电路来停用晶闸管。必威体育怎么登录为了克服这个问题,使用GTO(栅极关闭晶闸管)装置。它是一种类似于正常晶闸管的电流控制设备。本文讨论了一个概述Gate Turn off Thyristor.

什么是门关闭晶闸管?

GTO术语代表“门关闭晶闸管”。它是双极半导体开关装置,包括三个端子,即阳极,阴极和栅极,如传统的晶闸管。它具有门关闭的容量。该设备用于通过栅极驱动电路打开和关闭主电流供应。下面讨论闸门关闭晶闸管的基础知识。


门关闭晶闸管
门关闭晶闸管

The门关闭晶闸管符号is shown below. To activate the GTO into the mode of conduction, a small positive gate current is required as well as through a negative pulse on the gate terminal; and it is capable of being switched off. In the following image, it includes double arrows on it which differentiate the thyristor from the ordinary thyristor. These arrows mainly specify the flow of current in the bidirectional throughout the gate terminal.

GTO Symbol
GTO Symbol

To deactivate the GTO, it uses a high gate current. Alternatively, in the conduction state, thus thyristor works like a normal thyristor including a small ON condition voltage drop. The switching speed of this gate turn-off thyristor is faster as compared to normal thyristor and also it has high current and voltage ratings as compared with功率晶体管.

目前,在市场上可获得不同类型的GTO,包括对称和不对称电压的能力。对称GTO只不过是一个GTO,它具有相同前方的能力以及适用于当前源的反向阻塞inverters, however, these are fairly slow. Asymmetric GTOs (A-GTOs) are mostly applicable because of their lower ON-state voltage drop as well as constant temperature characteristics.

Construction Gate Turn Off Thyristor

The structure of the gate turn off thyristor is similar to a normal thyristor because it includes 3-junctions and 4- PNPN layers. A GTO is a three-terminal PNPN device like anode, cathode, and gate. In this kind of thyristor, the anode terminal is composed of a p+ layer through n+ type fingers diffused within it.


The N+ layer of this thyristor is doped highly to get high emitter efficiency and it provides a cathode terminal. Thus, the junction like J3 breakdown voltage is low and the typical breakdown voltage value ranges from 20 to 40V. The P-layer doping level must be low to maintain excellent emitter efficiency. Similarly, to have a good switch OFF properties, the region doping must be high.

门的施工关闭晶闸管
门的施工关闭晶闸管

阳极结可以定义为P +阳极以及N碱基的连接,称为阳极结。通过P +阳极区域可以通过重掺杂的P +阳极区域获得高效阳极结,从而可以实现良好开关的性质。但是,关机功能受此类GTO的影响。

因此,通过在P +阳极层内以正常间隔掺杂的N +层来解决这个问题。因此,在结j1时,该n +层将通过n层进行直接接触。因此,电子可以从基座区域移动到P +阳极的阳极金属接触而不引起空穴注入,因此这被称为具有阳极的GTO结构。

由于这些阳极短路,GTO的反向阻挡容量可以朝向J3结的反向击穿电压降低,因此可以增加关闭装置。但是,使用多个阳极短路,可以减少阳极结的效率,因此GTO对性能的开关可以降低。因此,必须对阳极短的密度进行仔细考虑,用于良好的开关打开/关闭性能。

Principle of Operation

GTO的操作原则与传统型晶闸管相同。一旦施加正栅极电流以使阳极端子正到阴极端子,那么就可以从阴极端子产生到阳极。因此,这在基区中的阳极端子的帮助下诱导空穴注入。这些电子以及孔注射连续直到栅极关闭晶闸管进入导通区域。

在晶闸管中,首先,传导通过开关在阴极区域上与栅极端子连续的开关开始。因此,剩余区域通过等离子体扩散进入传导。
不像晶体管,门关闭晶闸管包括窄阴极元件,该阴极元件通过栅极终端互连,从而早期转动区域是极大的,等离子体展开很小。因此,门关闭晶闸管非常快速地进入导电区域。

At the gate terminal, a reverse bias can be applied to switch OFF a conducting thyristor by making the gate terminal negative as compared with the cathode. In the P-layer, a fraction of the holes can be extracted using the gate terminal to hold back the electrons injection from the cathode terminal.

In reply to this, an extra hole current can be removed by the gate terminal which results in more control of electrons from the cathode terminal. Finally across the p-base junction, the voltage drop can cause reverse bias in the cathode junction of the gate & therefore the thyristor will be deactivated.

Throughout the process of hole extraction, the area of the p-base is slowly exhausted so that the conduction region can be squeezed. As this procedure continues, then the anode current supplies in remote areas by forming filaments with high current density. So, this can cause limited hot spots which can damage the device if not these filaments are extinguished rapidly.

在高负栅极电压施加期间,这些长丝迅速熄灭。由于N基区域中的存储电荷,尽管阴极电流停止,但阳极端子与栅极电流一起流动。因此,这被称为尾电流,当通过重组过程减少剩余电荷载流子时,尾电流分解。当尾电流水平降低到漏电流水平时,设备保持转发阻塞的特性。

V-I Characteristics

The Gate Turn Off thyristor V-I characteristics are related to a CT or conventional thyristor. The GTO’s latching current is more than a CT. For GTO, the latching current is 2A whereas, for a CT, it ranges from 100 mA – 200 mA. The V-I characteristics of GTO are shown below.

上述特性主要包括四个区域或模式,如前向阻断,正向导通,反向阻塞和反向传导。

Characterisitcs of GTO
Characterisitcs of GTO

在类似转发阻塞的第一模式中,电压在晶闸管上施加而不施加+ VE栅极信号。因此,它不在这种模式下进行。但是,与晶闸管的漏电流相比,有一点漏电流非常高。实际上,在这种模式下,门关闭晶闸管就像a晶体管具有高电压和低增益的意思,阳极电流低。在这种模式下,当栅极端子对阴极屈服时,GTO简单地阻挡额定正向电压。

当具有适当幅度的正栅极信号与GTO具有适当的幅度时,然后移动到转发传导的模式中。类似地,每当反向电压到该晶闸管时,它会阻挡直到极限的反向电压,但一旦逆电压达到临界值,称为反向断开过电压,则GTO开始沿反向导通。

如果栅极偏压并且该操作的时间小,则这种操作模式不会破坏设备。在反向偏置条件下,阻塞容量主要取决于GTO型。对称类型包括高反向阻塞能力,而非对称类型包括从20-30 V的小反向阻挡容量。

好处

The门的优点关闭晶闸管包括以下这些。

  • GTO具有出色的开关特性
  • GTO电路的配置具有比晶闸管电路单元更小的重量和尺寸。
  • 不需要换向电路,因此成本,重量和大小可以减少。
  • The switching speed of GTO is high as compared with SCR.
  • Less maintenance
  • 目前的浪涌容量类似于SCR。
  • GTO的阻塞电压容量高
  • di/dt ratings are more at turn ON
  • 效率很高

缺点

The门的缺点关闭晶闸管包括以下这些。

  • 相关的损失,以及导通电压降更多
  • The structure of GTO is multi-layered, so the gate triggering current value is high as compared to the conventional thyristor.
  • 闸门驱动电路的高损耗
  • The voltage drop of ON state across the gate turn off thyristor is more.
  • 与SCR相比,锁存和保持电流的幅度很高
  • 闩锁电流值为2a,而对于scr,它的范围从100 mA到500 mA。
  • 与SCR相比,GTO的触发电流很高

应用程序

由于与另一个晶闸管相比,GTO在许多应用中使用了许多效益,如出色的开关特性,维护较少,不需要换向电路等。门关闭晶闸管的应用包括以下内容。

  • 在快速和逆变器中,它用作主控制装置。
  • 交流驾驶
  • DC驱动器
  • 直流断路器
  • DC否则DC驱动器
  • 感应加热
  • 用于牵引应用,因为重量较少
  • 低功耗应用
  • 交流稳定电源
  • 它是用于逆变器、svc (static VAR compensators)
  • 用于驱动系统,如轧机,机床和机器人等。

因此,这一切都是关于an overview of gate turn-off thyristor(GTO)如建筑,工作,优势,缺点及其应用。该装置来自晶体管的系列,以及属于功率半导体器件组。该设备可以通过栅极或控制终端的帮助,通过打开/关闭状态。这是一个问题为您,市场上有哪些类型的晶闸管?

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