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The IGBT module requires special attention in preventive maintenance plans. More precisely, it is not the module itself that requires this attention, but different elements of the servo system that directly interfere with the IGBT. Understanding the possible failures of crucial components such as IGBT modules is essential. Perhaps the first step is to define exactly what an IGBT module is.

The IGBT module.

An IGBT module, which stands for Insulated Gate Bipolar Transistor, is a semiconductor device that combines the characteristics of two types of transistors. Specifically, the bipolar junction transistor (BJT) and the field effect transistor (FET). It is designed to control large currents and voltages in power electronics applications.

IGBT modules play a crucial role in power electronics. They enable the efficient control of large currents and voltages, thus facilitating the regulation and variation of electrical power in various industrial and commercial applications.

Functions of the IGBT Module.

Specifically, the IGBT module has five typical applications.

  • Power Amplification and Switching: IGBTs are used in power electronics systems to amplify and switch large amounts of electrical power. They can handle significant currents and voltages, making them ideal for motor control applications, frequency inverters, power supply systems, and other applications where efficient power regulation is required.
  • Current Control: IGBTs allow precise control of the electrical current flowing through them. This is essential in applications where the amount of power supplied needs to be modulated, such as electric motors, variable speed drives and power converters.
  • Switch Controlled: IGBTs act as electronically controlled switches. They can be quickly switched on and off by a control signal. This facilitates power regulation and enables energy efficient performance.
  • Electrical Isolation: The oxide layer on the IGBT provides electrical isolation between the control gate and the main part of the device. This isolation contributes to improved safety and allows precise control without the risk of short circuits.
  • Typical Applications: IGBT modules are essential in a variety of applications, such as electric drive systems in vehicles, industrial motor control, regulated power supplies, frequency inverters for renewable energy systems, among others.

Breakdown of IGBT Module Failures.

  • Overheating: One of the most common causes of failure in IGBT modules is overheating. This phenomenon can be due to excessive currents, inadequate design of the cooling system or even unfavourable environmental conditions. Overheating can manifest itself as deformation in the package and affect the conductivity of the device.
  • Overvoltage and Overcurrent: Uncontrolled variations in electrical voltage and current can cause severe damage to IGBT modules. Overvoltage and overcurrent can cause arcing, compromising the integrity of the device and affecting its switching capability.
  • Mechanical Damage: Shock, vibration or rough handling can cause mechanical damage to IGBT modules. Even small cracks in the package can compromise the efficiency and reliability of the component.

Case Study: Breakdown in an ALLEN BRADLEY Driver.

Throughout this article we can see different images of an ALLEN BRADLEY brand driver. It is specifically the model 20BC072A0AYNANC0. By simple inspection it can be seen that the IGBT module was exploded, with the door plate loose, with the resistors and diodes in poor condition. The precharge relays were stuck together.

The repair involved replacing the IGBT, as it was totally unserviceable. In addition, the repair of the gates and of course the replacement of the capacitors was obvious.

The picture on the left clearly reveals the devastating effects of the failure, highlighting the importance of understanding and preventing these problems. We can also see different moments of the inspection measurements, in order to locate damaged elements.

Preventive Maintenance: Key Strategies.

These devices require preventive maintenance to avoid the typical breakdowns mentioned above. A good preventive maintenance plan almost completely eliminates breakdowns linked to component wear and tear. Many of the potential failures are also evident with signs that can be easily detected by simple visual inspections.

  • Periodic Visual Inspections: Regular visual inspections can help identify early signs of damage, such as discolouration, deformation or cracks in the IGBT package.
  • Electrical Parameter Monitoring: Implementing monitoring systems to continuously monitor voltage, current and temperature can help detect anomalies before they become major problems.
  • Cooling System Optimisation: Ensuring that the cooling system is properly designed and operating efficiently is crucial to prevent overheating and ensure optimal performance.
  • Staff Training: Providing adequate training to maintenance staff is essential. This ensures careful handling of components and application of safe practices.

The Influence of IGBTs on industrial maintenance.

Understanding the potential failures in IGBT modules is critical to ensuring the continued operability of servo drive systems. Through preventive maintenance practices and the application of specific strategies, such as those mentioned above, companies can avoid costly downtime and extend the life of their equipment. The striking image of the ALLEN BRADLEY IGBT module underlines the importance of taking proactive measures to safeguard the integrity of industrial systems.

In the image on the left we can see another IGBT module, in this case from HOMAG, which shows a very similar explosion to the one we have seen in the previous image. It is clear that these devices need preventive maintenance to avoid these situations.

Good preventive maintenance avoids this type of breakdowns and unwanted stops in production. If you want to know more about these devices or if you have any problem with them,