Variable Frequency Drives Thirty Years Ago
The first Variable Frequency Drive that I remember was installed as a part of the Osaka Gas Pavilion on Expo 90 in Osaka, Japan. It was used to smoothly move the final scenery in the pavilion theatre.
That was thirty years ago and at that time I was responsible for the control systems and the programming for the entire pavilion. This VFD installation represented the absolute latest and greatest technology.
Before the 1990s, VFDs were very expensive and only used in heavy industry for large motors. I remember when one such drive was installed at a paper mill where my father was the R&D Manager.
However, advances in IGBT technology (these are the transistors that are creating output voltage for the motors) in the 1990s meant the VFD technology was becoming less expensive, switching frequency was higher (so the annoying VFD noise was mostly eliminated) and used more often in industrial applications. At the same time inverter grade motors were launched in the 1990.
VFD Meets Ecogate
The first VFD used inside the Ecogate solution was installed in 2000. Some twenty years ago.
By 2000, the advancements in IGBT transistors, processors, and software made VFDs even more reliable and accessible. The VFD is key for Ecogate on-demand ventilation systems: based on fan law, a small reduction of the fan RPM results in huge electricity saving (reducing fan RPM by 20% results in reducing the power by 50%).
Today, around the globe, renewable electricity along with energy efficiency is a key measure to stop global warming. In the USA, AC industrial motors represent 23% of total electricity consumption (971 TWh/year in 2018). Despite a greater acceptance of the VFDs, they are unfortunately still used only with a small percentage of industrial AC motors.
Modern Day VFDs
Modern day VFDs have come a long way since the 1990s when they were solely used in heavy industry. A new generation of devices like ABBs motor combined with VFD (EC Titanium motor) or Matrix drive by Yaskawa (U1000 Industrial Drive) show the way to the future.
By the way, the most advanced, most efficient VFDs are now in electric cars. They use a new class of more efficient output silicon carbide transistors. The Silicon Carbide (SiC) MOSFETs transistors have lower on state resistance and higher thermal conductivity than their silicon counterparts. It results in higher efficienc