Thyristor frequency converter was reconstructed for Alper a.s., Prostějov. Together with a three-phase separating transformer and the load of oscillatory circuit, which is induction billet heater SOP 500/3-A40 L/L/T, it is used for induction heating of steel billets with circular or square cross-section up to forging temperature.
The aim of the reconstruction was to increase the reliability of its operation. During the reconstruction, the existing controller was replaced by a new one with four base units with progressive CMOS integrated circuits. Also a Programmable Logic Controller was added and the water management system including thyristor coolers was exchanged.
| Nominal input values (power circuits) | ||
| Power Input [kVA] | 600 | |
| Input voltage from separating transformer [V] | 3 x 400 | |
| Frequency [Hz] | 50 | |
| Nominal input values (control circuits) | ||
| Power Input [kVA] | 3 | |
| Voltage [V] | 3 x 400 | |
| Frequency [Hz] | 50 | |
| Cooling water (external cooling loop) | ||
| Consumption [m3/h] | 4,8 | |
| Input temperature [°C] | max. 32 | |
| Input pressure [MPa] | max. 0,4 | |
| Pressure loss [MPa] | 0,12 | |
| Maximum warming thru loop [K] | 5 | |
| Cooling water (internal cooling loop) | ||
| System capacity [l] | 30 | |
| Nominal output values | ||
| Output [kW] | 500 | |
| Nominal output voltage [V] | 600 | |
| Frequency [kHz] | 1 - 3 | |
| Ostatní parametry | ||
| Dimensions (d x š x v) [mm] | 1430 x 830 x 2100 | |
| Weight [kg] | 1300 | |
| Cabinet | IP 43 | |
| Color | RAL 7035 | |