Diode

Power Switches

综合

选择依据

  1. 控制权
    1. 可控性 Controllability
  1. 电压降
    1. 导通电阻 Conduction Resistance
  1. 电压阻断
    1. 额定电压 Voltage Rating
  1. 承载电流
    1. 额定电流 Current Rating
  1. 开关时间
    1. 开关频率 Switching Frequency

种类

  1. Thyristors (Silicon Controlled Rectifiers; SCRs) 晶闸管 (half-controlled)
  1. GTOs (Gate turn-off Thyristors) 可关断晶闸管 (fully controlled)
  1. TRIACs (triode for alternating current) 双向晶闸管(half-controlled)
  1. MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) (fully controlled)
  1. GTR (Giant Transistor)大功率晶体管 (fully controlled)
  1. IGBT (Insulated Gate Bipolar Transistors) 绝缘栅极双极性晶体管 (fully controlled)
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SCR

TRIAC

GTO

BJT / GTR

MOSFET

  1. 电压完全控制装置

问答

  1. 并联
    1. 电流在可用器件中自动平衡
      1. because current is balanced among available devices automatically.
    2. 正温度效应 positive temperature coefficient
      3. MOSFETs can be paralleled very easily, because of  the positive temperature coefficient of their on-state  resistance. For the same junction temperature, if  RDS(on) of T2 exceeds that of T1, then during the on  state, T1 will have a higher current and thus higher  power loss compared to T2, since the same voltage  appears across both transistors. Therefore, the  junction temperature of T1 will increase along with its
      on-state resistance. This will cause its share of current to decrease and, hence, there is a thermal stabilization effect
      notion image
       
  1. 漏极和源极之间可能有很大电容
  1. 脉冲宽度调制
    1. By changing the width of the gate pulse in  relation to the operating frequency we can  vary the width of the current pulses in the  load. This is called Pulse Width Modulation

种类

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图像分析

  1. V-I
      2. notion image
 
  1. V-I
      2. notion image
 

参数分析

  1. 功率损耗 Power Dissipation
    1. 导通损耗 On-State Conduction Losses
     

    IGBT