The crux of the problem has to do with the direct current (DC) generated by solar panels being changed to alternating current, which occurs when the current is passed through an inverter circuit; specifically, the power loss occurs in the devices used within the solar system.
Now, what’s interesting here is that cutting power loss in insulated-gate bipolar transistors actually enhances the power generation performance of solar systems. And it’s not just with this technology – it also has a positive effect for uninterruptible power systems (UPS) in server rooms / data centers because power here has to constantly pass through a power converter circuit for the purpose of monitoring the supply and making sure power never goes interrupted.
One company that has taken IGBT’s already established advantages and improved them is Renesas. The company claims it has achieved the industry’s first TO-247 plus package for a 1,250V IGBT with built-in diode. And it achieved this mark by incorporating a metal to the underside of the TO-247 so that heat generated by the IGBT’s power loss can be quickly and efficiently transferred to the package’s exterior.
As a result of this improvement, the device is able to function even when exposed to temperatures of up to 175 degrees Celsius.
An additional advantage to this newly designed IGBT is the company’s use of a trench gate configuration in the process structure. Renesas officials explains explained this design solution is exclusive to the company, and that it allows the device to more easily achieve a combination of fast switching performance and low saturation voltage features. The result is a 30% increase in performance index.
Worth noting about these new IGBTs—Renesas also took a closer look at the various elements contributing to power loss in inverter circuits, and designed these new devices specially to minimize conduction and switching loss. The company also claims there’s less gate noise during the actual switching; this, in turn, allows system manufacturers to completely eliminate the gate resistors that were included with previous IGBT iterations for the sole purpose of reducing noise.
To learn more, reference the specification sheet for the company’s 8th generation G8H IGBT Series.