New Industry Products

Proton-Electrotex Unveils Thyristor Modules With Increased Power Density

November 17, 2020 by Gary Elinoff

The new devices feature higher surge current ratings and lower thermal junction-case resistance

The new МТ3-700-18-А2 modules are solidly based on their predecessor devices, the МТ3-540-18-А2. The higher power density was achieved by improving the semiconductor topology, with very few changes to other design elements. This involved increasing the active cathode area by 10%, reducing the thickness of the diffusion element and improving the diffusion profile. 

 

Image courtesy of Proton-Electrotex
Image courtesy of Proton-Electrotex

 

The new МТ3-700-18-А2 Thyristor Modules feature repetitive peak off-state and reverse voltage (VDRM/ VRRM) values are 1400 - 1800 volts. Turn off time (TQ) is 250 µs.

 

As compared to the previous MT3-540-18

  • The junction to case thermal resistance (Rthjc), has improved by 8% to 0.049 ℃/W per arm
  • Surge on-state current is up 20% to 23 kA
  • Mean current in open state (ITAV) has increased by 20% to 700 amps

 

Available Configurations for the МТ3-700-18-А2

The new device is available as a:

  • Thyristor module (MT)
  • Thyristor – Diode module (MT/D)
  • Diode – Thyristor module (MD/T)

 

Internally, the sub-units are connected as either:

  • In a serial connection
  • Common cathode mode
  • Common anode mode

 

The wide array of choices are illustrated as below:

 

Thyristor module, from left to right: serial connection, common cathode, common anode.
Thyristor module, from left to right: serial connection, common cathode, common anode. Modified image courtesy of Proton-Electrotex Data Sheet

 

The next diagram illustrates the Thyristor – Diode modules (MT/D) and the Diode – Thyristor modules (MD/T). 

 

Modified image courtesy of Proton-Electrotex Data Sheet
Modified image courtesy of Proton-Electrotex Data Sheet

 

Going from left to right, the 1st, 3rd, and 5th places are the serial connection, common cathode, and common anode MT/D modules. 

Again going from left to right, the 2nd, 4th, and 6th places are the serial connection, common cathode, and common anode MD/T modules. 

 

Important Maximum Allowable Ratings for МТ3-700-18-А2 Thyristor Modules

Triggering

  • Peak forward gate current (IFGM): 8 amps
  • Peak reverse gate voltage (VRGM): 5 volts
  • Gate power dissipation (PG): 4 watts

 

Switching

  • Critical rate of rise of on-state current, non-repetitive ((diT/dt)crit): 1000 amps/microsecond (f=1 Hz)

 

Mechanical

  • Acceleration under vibration: 50 meters/second2

 

Representative Characteristics for the МТ3-700-18-А2 Thyristor Modules

Triggering

  • Gate trigger direct voltage (VGT ): Ranges from 1.0 to 2.0 volts, depending on junction temperature
  • Gate trigger direct current (IGT): Ranges from 100 to 300 mA,  depending on junction temperature

 

Switching

  • Total recovered charge (QRR): 1800 µC
  • Delay time: (tgd):    1.0 µsec
  • Turn-on time: (tgt): 3.0 µsec
  • Turn-off time: (tq): 250 µsec

 

Applications

  • Energy conversion
  • AC regulators
  • Electric drives
  • Power sources
  • Rectifier bridges
  • DC motor control

 

Physical Considerations

Mounting the МТ3-700-18-А2 Thyristor Modules is simplified because the necessary pressure of the semiconductor element is provided structurally 

Junction temperature can range from -40 to +130 ℃ 

As can be seen from the picture at the top of this article, these Modules, like all devices of this type, have a complex geometric shape. At their largest extent, length and width are 149 by 60 by mm 

Weight is 1500 grams