1. From the First Motors to Electronic Control

The history of frequency inverters parallels the evolution of industrial automation. The induction motor, invented by Nikola Tesla in 1888, became the basis of industrial electrification. However, for decades, speed control was still limited, expensive, and inefficient.

The first inverters began to appear in the 1960s and 1970s, using thyristors (SCRs). These were large and inefficient devices, used only in specific applications.

2. The Arrival of Bipolar Transistors

In the 1970s, the first frequency inverters based on bipolar power transistors (BJTs) appeared. They represented a significant advance, as they allowed higher switching frequencies than thyristors, resulting in lower vibration, greater efficiency, and better motor performance.

Even so, they presented challenges such as high heat generation and complex control, but they were fundamental in paving the way for the next generation.

3. The IGBT and DSP Revolution

In the 1980s and 1990s, two advances definitively changed the market:

IGBTs (Insulated Gate Bipolar Transistors), which combined the robust current of BJTs with the speed of MOSFETs. They made inverters more compact, reliable, and efficient.

DSPs (Digital Signal Processors), which enabled the use of advanced control algorithms, such as vector and PID, bringing precision and flexibility to industrial applications.

Thanks to these technologies, inverters have established themselves as indispensable equipment in factories, automation systems, and even critical energy applications.

4. Provolt and National Development

Provolt, founded in 1988 in Blumenau, Santa Catarina, closely followed this evolution. As early as 1990, it began developing its own frequency inverters, at a time when the technology was still gaining traction in Brazil.

Over time, the company incorporated modern IGBTs and high-performance DSPs into its lines, increasing the reliability of its products and ensuring competitive solutions for industrial and critical applications.

5. Lines and Differentiators

CFP-II – Developed in Brazil, it uses an integrated DSP and IGBTs, standing out for its practicality and robustness.

PI (imported) – Compact, high-performance equipment, also based on IGBTs and 32-bit DSPs, ideal for demanding applications.

PFlex One – The world's first inverter with a housing produced entirely using 3D printing in ABS, combining national innovation with global power and digital control technologies.

6. Conclusion

The history of variable frequency drives is marked by stages of innovation: from thyristors to bipolar transistors, from these to IGBTs, and finally to the era of digital control with DSPs.

Provolt's trajectory reflects this evolution, demonstrating how a Brazilian company was able to keep pace with each technological leap and develop its own robust and modern solutions for the industry.