IPMs – An Answer for Compact Motor Drive Applications?

Application

Greater integration and much more complex subsystems are the current mega trends in power electronics. Extremely popular are Intelligent Power Modules (IPM) for motor drive applications. They’re a mix of power semiconductors like IGBTs, MOSFETs and diodes with peripheral components like driver circuits. If whole subsystems have a very good match to applications, an IPM may bring various benefits.

Transfer Molded IPMs

Very frequently IPMs are created inside a transfer molding process. The ability semiconductors along with other components are installed on a lead frame. For isolation and protection things are molded with plastic. The benefit of fraxel treatments may be the simple production process. Disadvantages would be the scale lower limitation from the lead frame and also the limited heat conductivity from the isolation material. The mechanical design also offers some strong limitations. Typical applications are consumer items like white-colored goods or inexpensive standard motor drives.

Thick-Film Technology

Another possibility for top integrated power electronics may be the thick-film technology. Different layers of conduction and isolating materials are printed on the ceramic sheet. The layers can take shape tracks, pads, or resistors. Benefits of fraxel treatments would be the good thermal conductivity and also the possible ways to create layouts much like a PCB. The style of the housings and also the pins don’t have any limitation. Thick-film is an extremely mature technology. It’s already being used for quite some time, particularly in critical applications, e.g. in the automotive industry.

One thick-film based intelligent power modules may be the flowIPM from Vincotech. This power module has power semiconductors for that rectifier along with a 3- phase inverter, an entire driver circuit with bootstrap circuit and shunt resistors for current sensing altogether in a single package. Optional a PFC (Power Factor Correction) power stage can also be integrated (MOSFET with driver, diode, and capacitor). Almost all components that are focusing on grid current are built-into the module.

Probably the most featured applications for that flowIPM take root motor drives. They are systems in which the motor and it is driving electronics are integrated, e.g. fans, pumps, compressors, ac, or professional tools. Many of these systems offering only limited space. The compact and frequently hermetical design is a huge problem for heat dissipation of electronic components. This kind of atmosphere is the best spot for the flowIPM to exhibit his strength:

High Integration: The flowIPM contains all power semiconductors and the majority of the peripherals for any motor drive. Just the big passive components need to be mounted individually. The bond pins are separated in 2 lines, one using the power connections and something using the control signals. An order from the power connections prevents any input/output crossings. The in- and outputs from the driver circuit take presctiption logic level and may directly linked to a microcontroller or similar.

Cooling Concept: The ceramic sheet of the IPM includes a really low thermal resistance. All components are put around the ceramic the ceramic is directly attached to the heatsink. All components are directly and optimal cooled. For that power semiconductors this will be relevant to possess good performance and efficiency. But additionally components like driver circuits and shunt resistors have a take advantage of a great cooling. Particularly when utilized in a hermetic atmosphere without air flow.