Recently, the high-speed permanent magnet motor fan high-voltage variable frequency drive (VFD) speed control system project custom-built by Guangzhou Zhiguang Electric Technology Co., Ltd. (hereinafter referred to as “Zhiguang Electric Technology”) for Shandong Tianrui Heavy Industry has been successfully commissioned. The project not only ensures stable and reliable equipment operation with high efficiency, but also sets a new benchmark for the application of high-power power electronics technology under special load conditions

This cooperation project focuses on the variable frequency control requirements of high-speed permanent magnet motor fans. Such loads are widely used in high-end manufacturing industries due to their high operating efficiency and high energy density. However, their rated frequency of up to 500 Hz and rated speed of 15,000 r/min impose extremely stringent performance requirements on VFD equipment.

To overcome this technical challenge, Zhiguang Electric Technology leveraged more than 20 years of R&D experience in high-power power electronics, combined with the customer’s actual operating conditions, to deliver a tailor-made integrated solution for an intelligent high-voltage variable frequency speed control system.

Shock-free startup, adaptable to complex operating conditions: An innovative proprietary “STT” speed-tracking algorithm accurately captures the motor’s rotational state, enabling shock-free startup at any speed. The system fully adapts to special scenarios such as fan “windmilling” or runaway conditions, ensuring safe start-up and shutdown of the equipment.

Efficient heat dissipation and loss control, outstanding stability: The system is equipped with an H-class insulated dry-type phase-shifting rectifier transformer, for which Zhiguang Electric Technology participated in drafting the industry standard. Combined with a hybrid cooling solution integrating forced air cooling and air-conditioning internal circulation, it effectively and evenly manages temperature rise under high-frequency operation, strictly controlling transformer losses within 2.5%, thereby extending equipment service life.

Low harmonic output, enhanced motor protection: By adopting multi-level sinusoidal PWM control technology, the output current harmonic THD is reduced to below 4%, far exceeding national standards. This fundamentally avoids damage to motor insulation caused by high-frequency harmonics and reduces equipment maintenance costs.

High energy efficiency with excellent control accuracy: Across a wide load range of 20%–100%, the system maintains an input power factor consistently above 0.95, achieving an overall operating efficiency of up to 96%. At the same time, fan control accuracy is improved to 0.01 Hz, delivering both energy savings and precise control.

As an innovation expert in high-power power electronics technology, Zhiguang Electric Technology’s high-voltage VFD products have been deployed and commissioned across multiple regions nationwide, with wide applications in power generation, metallurgy, petrochemicals, and other industries.

The success of this project fully demonstrates Zhiguang Electric Technology’s technical strength in variable frequency control for special loads. Looking ahead, the company will continue to focus on the R&D of high-power power electronics, providing more innovative solutions to meet market demands and driving efficiency improvement and energy-saving upgrades across the industrial sector.