Case studies: Preventive measures on 2 Masterdrives (800 kW, cabinet with 3 doors)

Project duration: 1 week Project hours: 80 hours

Customer Expectations

Our steel industry client commissioned us to carry out preventive maintenance checks on its two master drives. These systems are critical, as a failure would endanger the blast furnace and cause production downtime and restoration costs running into the millions. Shutdowns must therefore be carefully planned and kept to a minimum, as the powerful but outdated converters are difficult to transport. Upgrading to new systems would be expensive and involve long downtimes.

**Solutions from DV GROUP**

The work was completed within one week and utilized two shutdowns planned by the customer.

Our measures:

* **Complete overhaul** of the converters
* **Risk minimization** through the use of two separate control systems

The first intervention took place in October 2024, the second is planned for January 2025.

**Work Completed**

*On-site:*

* Use of a crane to unload the dismantled parts from the elevated electrical room
* **Disassembly of all components**: capacitors, power supply board, CPU, fans, and IGBT control boards
* **Renewal of the thermal paste** of the IGBTs

*In our workshops:*

* Replacement of **90 capacitors**
* **Modernization of the circuit boards** by replacing wear parts and optical transceivers
* **Overhaul of the fans** with new bearings and capacitors

**Customer Benefits and Advantages**

* 90% remanufactured converters in less than one week
* Significantly increased operational reliability and greatly reduced risk of failure
* In-depth understanding of the systems, enabling fast and efficient interventions