1.Application Scenarios
Industrial frequency converters are used for motor speed control and are widely applied in industrial equipment such as fans, pumps, compressors, conveyors, and machine tools, with power ratings ranging from a few hundred watts to megawatt levels.
2.The Role of the Product in the System
| Product Category | System Function |
| Bridge rectifier | Rectify three-phase AC input into DC bus voltage |
| Soft recovery/fast recovery diode | Used as IGBT freewheeling diode (FRD) to reduce switching losses |
| SiC diode | PFC or auxiliary power supply for high-frequency design to improve efficiency |
3. Recommended Product Model
| Product Category | Recommended Series/Model (Example) | Key Parameters |
| Three-phase rectifier bridge | GBU/GBJ series (25A – 50A/800V – 1600V) | VF low, strong surge resistance |
| Fast recovery diode | FRxx series (600V-1200V) | Trr < 100ns |
| Ultra soft recovery diode | USRxx series | High soft recovery factor and low EMI |
| SiC diode | SiC SBD(650V/1200V) | Zero reverse recovery, suitable for high frequencies |
4. AC/DC Module Application
● The front-end AC/DC is completed by a three-phase rectifier bridge and a filtering capacitor
● The auxiliary power supply can adopt a flyback topology, using 600V/650V MOSFET+RCD absorption diode
5. Application of PFC Circuit
● High power frequency converters (>5kW) can increase single-phase/three-phase PFC, and it is recommended to use SiC diodes+super junction MOSFETs interleaved parallel PFC topology
● Low power frequency converters usually do not have a separate PFC stage
6. Common Customer Needs
| Demand | Our Response |
| “The efficiency of the frequency converter should reach over 98%” | Recommend low VF rectifier bridge+low Rds (on) MOSFET, provide efficiency test report |
| “EMI radiation exceeds the standard” | Recommend ultra soft recovery diode to reduce switch ringing |
| “Motor low-speed vibration” | Provide optimization suggestions for IGBT/MOSFET drivers |
| “CE/UL certification is required” | Provide device certification documents and EMC rectification suggestions |