Thyristor gate drive units  

Preferred in high power systems with low switching frequency

In many applications, especially in systems with high power and relatively low switching frequency, the thyristor is still the first choice among the large variety of available power semiconductors. In conjunction with the right gate control, it is able to conduct and switch large currents with low conduction losses over many years or even decades without requiring maintenance.

Thyristor gate drive unit

Astrol’s thyristor gate drive units combine various functions in an optimized circuit design and have proven to be extremely reliable and efficient in hundreds of projects over the last twenty years.

Optical triggering vs. triggering via Power Loop

Depending on the application, our customers can choose between two main option of gate triggering, the triggering via Power Loop and the optical triggering.

Triggering via the power loop is the most cost-effective method of controlling series-connected thyristors. The gate trigger pulses are generated by a single device, the GU-LCT, which sends the pulses to the various stack levels via the power loop. Connected to the power loop by inductive coupling, the GU-LCTind receives the energy pulse and sends it to the thyristor gate. If all GU-LCTinds are connected to the same power loop, all levels receive the pulse at exactly the same time. Simultaneous control of the gate can be achieved with a minimum of components and complexity.

More complex systems which special requirements, such as high di/dt, swich-off capability or backporch functionality require the separation of gate drive unit power supply and triggering.

Our offering of thyristor gate drive units

GU-LCT  and GU-LCT_IND: The cost effective solution for series connected thyristors.

  • Comprises one trigger pulse generator and up to 24 inductive coupled boards
  • Simultaneous triggering
  • Optical interface for trigger signal from system controller
  • Optical status feedback to system controller

GU-NT: Thyristor gate unit with optical trigger input and feedback

  • Comprises one trigger pulse generator and up to 24 inductive coupled boards

GU-NT dual: Thyristor gate unit with all the feature of the GU-NT, but able to simultaneously control two thyristors in anti-parallel connection.

  • GU-SGMIII                              
  • GU-PCT-Crowbar
  • GU-Crowbar 40kV

At Astrol, we are more than just a design partner. With our commitment to quality, innovation, and customer satisfaction, we are your long-term collaborator in success.

Astrol long-term collaborator

We answer all your technical and application related questions

Send your question(s) to