What is the reason for applying reverse-bias voltage (-VGE) between the gate and emitter?

An insufficient reverse-bias voltage (-VGE) between the gate and emitter may cause the IGBT to mis-fire, leading to a short-circuit current. If the current is cut off the surge voltage and the generated loss may damage the product. For details, refer to Application Manual Chapters 4-3.3 and 7-1.2.

Which terminal should be used to measure the collector-emitter voltage (VCE) when switching?

Please measure at the main terminal of the product. If a terminal is separately specified for measurement in the data sheet, please use the specified terminal.

What are the points we need to be aware of when determining the gate resistance (RG)?

A larger gate resistance (RG) will increase switching loss, and make it more prone to generating an arm short circuit due to an insufficient dead-time. A smaller gate resistance (RG)may cause a sudden surge voltage. For details, refer to Application Manual Chapters 2-2.2 and 7-1.3.

What ohm value is set for internal gate resistance (RG) in an IGBT module?

“Refer to the data sheet where internal gate resistance (RG) values for the 6th-generation V-series and 7th-generation X-series IGBT module are described. Please contact us with a model type number if it is not shown in the 6th-generation data sheet or if it is a product prior to the 6th-generation (U-series, S-series).”

How can the surge voltage be reduced?

A surge voltage is generated by high di/dt, and wiring inductance outside the module, at the time of switching (L*di/dt). Some of the ways to suppress this problem are as follows: (1) Add a protective circuit (2) Reduce di/dt by adjusting RG or –VGE (3) Reduce inductance by making the main circuit wiring thicker and […]

How should the gate resistance (RG) be determined?

The gate resistance value (RG) greatly impacts dv/dt, radiation noise, voltage/current surge, and switching loss. Please comprehensively determine an appropriate value that corresponds to the target figure of your actual design. As for reference, a recommended turn-on resistance value (RG(on)) is twice or higher than that of the standard value from datasheet, and a recommended […]

Is it always expedient to use the gate resistance (RG) value indicated in the data sheet?

The optimum gate resistance value (RG) varies depending on the circuit configuration or operating environment used. The data sheet describes the recommended resistance value to minimize switching loss. Determine an appropriate gate resistance (RG) after considering the relevant switching loss, EMC/EMI, surge voltage, and unexpected characteristics such as vibration, without deviating from the descriptions contained […]

Can the voltage exceed IGBT’s maximum collector-emitter voltage (VCES) for a short time?

Maximum collector-emitter voltage (VCES) is specified as the maximum rating in the relevant specifications. The voltage should never exceed this value.

How do I select a module by the rated parameters?

Regarding voltage and current rating, refer to Application Manual Chapter 3-1 on “how to select an IGBT module”. Before use, please verify that the voltage, current, temperature, and other factors stay within the maximum rating range. Please contact Fuji Electric Corp. of America or your local sales representative or distributor for support.

What is the difference between PIM and IPM?

PIM is a product that integrates a 3-phase converter circuit, brake circuit, and 3-phase inverter circuit into a single module. This leads to a compact main circuit design. IPM, on the other hand, offers an advantage of simple peripheral circuit designing, by use of its built-in control IC. This IC contains gate driving and protection […]