Laminated Busbars
Busbars are specialized components made of copper, used to create low-profile, high-current busbar connections in power electronic devices. Their design aims to minimize parasitic inductance and limit electromagnetic interference (EMI) emissions, making them an indispensable component of modern power converters, especially where fast power transistors, such as IGBTs, are used.
Why busbars?
Modern power electronic converters use high-frequency IGBT transistor modules. During their switching, overvoltages can occur at the terminals, the main cause of which is the parasitic inductance of the converter's internal connections. Rapid changes in high current values flowing through these internal connections are now between 1 and 2.5 kA/μs, and they cause overvoltage to be induced at the transistor terminals, which the transistor must withstand in the blocking state.
Overvoltages generated during converter operation negatively affect its performance and are, among other things, a source of electromagnetic interference. They also impact the quality of waveforms obtained at the converter's output or, in extreme cases, can lead to damage to the IGBT modules.
The parasitic inductances of connections cannot be completely eliminated, but their value can be reduced by using low-inductance busbar connections.
Benefits of using busbars
Low-inductance busbar connections are made in the form of two or more electrically conductive layers separated by a dielectric layer. A beneficial aspect of using low-inductance laminated busbar connections is the reduction of costs associated with making the converter's internal connections by streamlining the device assembly process (shortening assembly time, high repeatability, and error elimination) and by eliminating or reducing the need for additional capacitors to suppress commutation overvoltages (Snubber cap).
Busbar solutions are successfully used in areas such as: rail transport, power supply systems, renewable energy sources (wind turbines), telecommunications, industrial power, and military applications.
What distinguishes our busbars
Laminated multi-layer construction - allows for several current paths to be run in a compact structure while maintaining minimal inductance and high current density.
Minimization of overvoltages - reduction of switching effects in transistor circuits with steep current slopes (up to 25 kA/μs).
Parameter stability - predictable electrical behavior, especially important in pulsed and converter circuits.
Optimized geometry - full customization is possible for a specific circuit, including the placement of connection points.
Applications of busbars
- inverters and power electronic converters
- industrial drive systems and UPS systems
- high-power power electronics (e.g., chargers, energy storage systems)
- applications where compact dimensions, low losses, and resistance to interference are key
