[Switch] Application of IGBT variable frequency power supply in Automobile Crankshaft Quenching

1 Preface

The modern induction heat treatment technology is widely used because of its high quality, high efficiency, and environmental protection. As the basis of induction heat treatment technology, the IGBT module of the inverter has been commercialized and has successfully produced 10 ~ 100 kHz IGBT inverter power supply with hundreds of kilowatts of power. Practice has proved that the use of IGBT variable-frequency power supply can completely replace the variable-frequency generator set with serious energy consumption.

2 working principle and features of IGBT Inverter Power Supply

IGBT Inverter Power Supply Circuit 1:

The Inverter adopts a single-phase bridge inverter circuit. The load is in the form of parallel resonance. The DC filter is used for large inductance filtering to meet the input requirements of the Parallel Inverter. The main function of inverter control adopts the timing principle to achieve automatic tracking of load frequency, inverter bridge startup, and provide reliable driving pulse for inverter bridge power devices. its working principle is 2.

The voltage signal obtained from the load is output ahead of time by adjusting the delay circuit, and the self-excited square wave signal is obtained through the zero-crossing comparison circuit. Before the inverter works, the voltage on the load is zero, so start with him. After the inverter is started successfully, when the power supply output voltage reaches a certain value, the level detection circuit outputs a flip, which converts the electronic switch output from the exclusive signal to the self-excitation signal, this completes the inverter startup process. The phase separation and driving circuit are used to drive the pulse correctly for the IGBT of the Four-arm power device of the inverter bridge.

The inverter is a current inverter. The input power of the inverter is P:

Load Voltage, And the AC equivalent impedance of the parallel resonant load circuit.

When the grid voltage of the IGBT variable-frequency power supply fluctuates by more than 10%, the output voltage fluctuation cannot exceed ± 1%. If the sensor is short-connected, the bus is short-connected, open-circuit, and the load capacitor is damaged, the overcurrent and overvoltage can be properly protected. The water cooling method has corresponding detection protection.

3. Actual Application Results

There are nine heating parts for Crankshaft quenching, which need to be heated separately. Because the nine parts must have their own load matching control parts, and the distance from the power supply equipment to the load matching part is far away, the sensor must be moved when the shaft neck quenching is heated, therefore, the power supply equipment used for Crankshaft quenching should meet the following conditions:

A. high efficiency with a 10-30 kHz frequency:

B. The Server Load balancer can be connected to multiple matching parts, and the size of matching parts is small;

C. The power loss must be small;

D. fast tracking of load changes.

IGBT Inverter Power Supply can fully meet the above requirements

Based on the above, the IGBT inverter power supply has the following advantages:

A. Significant energy saving. During operation, the inverter power supply ratio of IGBT is about 10% ~ 18%; no-load IGBT inverter power loss is very small.

B. High Efficiency under rated load.

C. The frequency can be automatically tracked.

D. small size, light quality, small footprint, and significant water saving.

[Switch] Application of IGBT variable frequency power supply in Automobile Crankshaft Quenching