A Beginner’s Guide to Power Modules

Power modules are the power switching/control circuit elements that are integrated into convenient isolated-base packages in order to offer a broad spectrum of commonly used diodes. They are often used to power semiconductor devices and provide an easy way to cool the device, as well as connect to the outer circuit.

They provide physical containment for several power components, usually power semiconductor devices which provide electrical and thermal contact and electrical insulation as needed. Compared to plastic housings, power modules provide a higher power density and, in many cases, are more reliable.

Characteristics of Power Modules

These devices are ensured to be mechanically and thermally optimized for easy assembly, long life, and reliable operation by power module manufacturers. There are several common structures that power modules are available in, such as IGBT or MOSFET.

Power Modules manufacturers maintain a similarity in qualities of diodes and thus power modules are often classified by the diode that they feature. Fast recovery, Hybrid SCR-High Voltage, Schottky, Standard, Standard Hybrid SCR, Standard SCR, etc. are common examples.

Applications of Power Modules

Power module manufacturers ensure power modules can be used in a variety of applications, such as Electroplating, Motor controls, AC, Motor controls, DC, Motor starters, Power Supplies, Heater controls, Elevator controls, Welding, Battery charging, Appliances, Switches, Transportation, Converters, HVAC controls, Inverters, Medical Electronic, and many more.

Intelligent Power Module

An intelligent power module contains additional control and protection circuitry with the goal of optimizing and making the overall solution easier to design and implement. It incorporates the digital intelligence usually provided by a microprocessor, which makes an IMP (Intelligent Power Module) advanced and highly integrated solid-state power switch.

Optimized high-power switching is more than just turning a switch on or off. Some of the basic functions of an IPM, over and above those of a regular power module, include:

1. Applying proper voltage and supplying large amounts of current for fast switching.
2. Protecting the circuitry by detecting and addressing overcurrent, overtemperature, short-circuit, and under-voltage conditions. 
3. Some applications also require power factor correction (PFC). 

Intelligent power module manufacturers try to integrate any feature or functionality that can enhance the device’s performance. These include increasing manufacturability, lowering the cost, accelerating the speed of switching, reducing its size, improving the reliability of circuitry or simplifying the device’s implementation in real-life applications.

Different Types of Power Modules

Components that help in providing a push or physical containment to several power units that are embedded in an electrical or electronic device are known as power modules. Among the most common devices where the use of power modules can be seen are semiconductor units, which are also called dies. They are soldered to the power electronic substrate that comprises of the power semiconductor, which allows for the supply of electrical and thermal contact, and electrical insulation, whenever required. Power modules have high power density, which makes them more durable and extremely reliable. In addition to this, power modules also allow for an efficient operation of electrical or electronic devices. Today, with several advancements in technology, power modules manufacturers have come up with several advanced products that can be used in a range of electrical and electronic devices for more effective and convenient operations.

The first power module was introduced in 1975. Ever since, they have contributed to the constructive operation of power devices. In addition to their extensive use in semiconductors, power modules are also used in power conversion devices like industrial motor drives, AC-DC, welded power supplies, and embedded motor drives. They can be also used in renewable energy inverters like wind turbines, electric vehicles (EV), tidal power plants, and solar power panels, to name a few.

Types of Power Modules

There are various types of power modules available today. However, the following are the main types that are offered by power modules manufacturers -

• Thyristor Modules: These are latch type modules that turn ON when the holding current reaches the required level and goes OFF when there is an alteration in the current. They are mainly used in welding machines, electric furnaces, motor controls, static switches, etc. 
• SiC-SBD: Another popular type of power module is the SiC-SBD module. It is designed with material characteristics that help in achieving significant power savings in home appliances that require heavy power.
• IGBT: IGBT power modules help in converting direct current to alternating current with minimal loss. They are used in various industrial applications as well as for wind power generation.

Power modules also have different network topologies for their operation. With the help of power modules, the needed power control of a device’s operation can be achieved efficiently.