Intelligent Power Modules (IPMs): Fundamentals, Features, and Applications

The presence of a power switching component (typically an IGBT) is referred to as a power module, and the module is referred to as “intelligent” because it includes additional control and protection circuitry. The goal is to improve performance while making the overall solution simpler to design and implement.

This terminology could be misconstrued. When one hears the words ” IGBT module,” one’s first thought is “power supply module” (such as a DC/DC converter) plus “processor.”

An  IGBT power module is essentially an integrated power supply device that includes the digital “intelligence” provided by a microprocessor.

IPM Features

Optimised high-power switching entails much more than simply switching on and off a FET or IGBT. The following list conveys features that could be incorporated into a power-switching application, as well as features found in intelligent power modules.

  • For fast switching, gate-drive circuitry must apply the appropriate voltage and provide large amounts of current.
  • Gate-drive logic can also be programmed to prevent both high-side and low-side IGBTs from conducting at the same time. Shoot-through protection, cross-conduction prevention, and interlock circuitry are some of the names for this functionality.
  • Overcurrent, overtemperature, short-circuit, and undervoltage conditions should be detectable and addressed by protection circuitry. If the system needs to keep track of fault events or operational temperatures, communication functionality will be required.
  • Specification for EMI may necessitate specialised switching behaviour.
  • Due to space or cost constraints, a designer may be forced to reduce power losses that occur during switching and on-state conduction in order to use a smaller heatsink or enclosure.
  • Power factor correction is required in some applications (PFC).

IGBT power module

The interlock functionality of the FNB81060T3, an ON Semiconductor 600 V IPM, is depicted in this diagram. Take note of how the high- and low-side gate voltages do not respond to input signals that would cause cross conduction.

Take note of how the high- and low-side gate voltages do not respond to input signals that would result in cross conduction.

Essentially, IPM manufacturers try to incorporate any feature or functionality they can into a semiconductor-based power-switching circuit in order to improve performance, increase manufacturability, lower cost, reduce size, improve reliability, simplify implementation, or accelerate time to market.

Voltage Specifications

The IGBT power module market is primarily focused on high-voltage applications. “High” is a relative term; in the language of low-voltage engineers like myself, 50 V might be considered “high,” but in the context of IPMs, it’s actually quite low.

Infineon’s CIPOS Nano family, for example, has a maximum voltage rating of 40 V and a maximum voltage rating of 600 V, and the Nano line is the smallest, lowest-power option in the company’s lineup. The Maxi family can withstand voltages of up to 1200 V and dissipate up to 50 W per IGBT module.

Form Factor 

Intelligent power modules are frequently packaged in non-standard through-hole packages. Some examples are as follows:

This is a model of the FNB81060T3
                                               This is a model of the FNB81060T3 (mentioned above).
Ipm with PFC for low-power devices.
                                                        Ipm with PFC for low-power devices.

Applications

Intelligent power modules are most commonly associated with motor control, but they are also found in uninterruptible power supplies, inverters, and renewable energy systems. The following is a list of some of the manufacturers’ intended applications.

  • Home appliances: Air purifiers, fans, air conditioners, washing machines, refrigerators, and vacuum cleaners.
  • Automotive: AC compressors, on-board charging in electric vehicles, and oil pumps.
  • Industrial: compressors, pumps, elevators, and
CISSOID created an aerospace IPM that employs silicon carbide (SiC) MOSFETs rather than IGBTs.
CISSOID created an aerospace IPM that employs silicon carbide (SiC) MOSFETs rather than IGBTs.

Conclusion

Intelligent power modules make it much easier to design a reliable, efficient, and compact circuit for high-power solid-state switching. These adaptable components can be used in a wide range of applications, and their popularity and importance will undoubtedly grow as system requirements and performance expectations become more difficult for designers to meet.