Electric motor windings transforming into an organized four-phase system.

Rethinking Motor Design: Can a Simpler Winding System Boost Efficiency?

Jordan Keane in Tech & Innovation December 2025 • 4 min read.

"Engineers explore a novel four-phase winding approach for single-phase induction motors, potentially reducing complexity and cost."

Induction motors are the workhorses of industry and home appliances due to their simple design and robust construction. Traditionally, these motors come in two main types: three-phase and single-phase. Three-phase motors, known for their high power capabilities, require a three-phase electrical system. Single-phase motors, typically found in lower-power applications, operate on a single-phase supply.

Operating three-phase motors on a single-phase power supply often involves adding capacitors to the windings. This approach essentially mimics a two-winding, single-phase capacitor motor. While functional, this workaround can be complex, prompting the search for simpler and more efficient solutions.

This article explores an innovative winding design for single-phase capacitor motors, drawing from research that investigates a four-phase winding system. This novel approach uses four identical windings, potentially streamlining motor construction and enhancing performance.

The Four-Phase Advantage: A Simpler Winding Design?

Electric motor windings transforming into an organized four-phase system.

The core of this innovation lies in redesigning the motor windings. Traditional single-phase motors use two distinct windings: a main and an auxiliary winding. The auxiliary winding, often paired with capacitors, creates the necessary phase difference to start and run the motor.

The research explores a different approach, adapting the principles of a four-phase induction motor. This involves using four identical windings, labeled U, V, W, and X, all with the same cross-sectional area. The U, V, and W windings are connected as auxiliary windings, while the X winding serves as the main winding.

Simpler Construction: The four identical windings simplify the manufacturing process.
Potential Cost Savings: A more streamlined design could translate to lower production costs.
Improved Performance: The design aims to enhance motor performance through optimized winding configuration.

To evaluate this new design, researchers compared it to a standard three-phase induction motor. The comparison motor had the following specifications: 1400 RPM, 1.5 HP, 50Hz, 380/220V, Υ/Δ, 2.74/4.7A, 4 poles. The windings in both motors were made of the same size wire (0.65 mm²).

Efficiency Gains and Future Directions

The results of the study indicated that the four-phase design could achieve 88.18% of the output power of the comparison motor, with a power factor approaching unity. This suggests that the motor design could operate close to the rated power of a comparable motor.

However, the efficiency of the prototype motor was lower than the three-phase motor. The researchers attribute this to using the same size winding for both the main and auxiliary windings. Limiting the current in both windings constrained the motor's overall performance.

Future research will focus on optimizing the size of the auxiliary windings, potentially increasing them to improve motor efficiency. This refinement could unlock the full potential of the four-phase winding design, paving the way for simpler, more efficient single-phase induction motors.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1051/matecconf/201821501023, Alternate LINK

Title: Windings Design For Single-Phase Induction Motors Base On 4-Phase Induction Motor (Case Study: Identical Windings Design)

Subject: General Medicine

Journal: MATEC Web of Conferences

Publisher: EDP Sciences

Authors: Zuriman Anthony, Erhaneli Erhaneli, Zulkarnaini Zulkarnaini

Published: 2018-01-01

Everything You Need To Know

How does the winding system in this new motor design differ from traditional single-phase motors?

The new motor design incorporates four identical windings (U, V, W, and X) each with the same cross-sectional area. Windings U, V, and W act as auxiliary windings, while winding X functions as the main winding. Traditional single-phase motors utilize two distinct windings: a main winding and an auxiliary winding.

What are the potential advantages of using a four-phase winding system in single-phase induction motors?

The four-phase winding design can potentially offer simpler construction because it uses four identical windings streamlining the manufacturing process. This could translate to potential cost savings due to the streamlined design, leading to lower production costs. Additionally, the design aims to enhance motor performance through an optimized winding configuration, potentially improving overall efficiency and output.

How does a three-phase motor differ from a single-phase motor, and where does the four-phase motor fit in?

Traditional three-phase motors are known for their high power capabilities and require a three-phase electrical system. Single-phase motors, on the other hand, are typically found in lower-power applications and operate on a single-phase supply. The four-phase system is designed for single-phase power, but seeks to improve efficiency and output compared to typical single-phase designs.

What existing motor was the four-phase motor design compared to, and what were its specifications?

Researchers compared the novel four-phase motor design with a standard three-phase induction motor having the following specifications: 1400 RPM, 1.5 HP, 50Hz, 380/220V, Υ/Δ, 2.74/4.7A, and 4 poles. Both motors used windings made of the same size wire (0.65 mm²). This comparison helped evaluate the performance and efficiency of the new design relative to a common industrial standard.

What performance metrics have been achieved using the four-phase design, and what do these results imply about its efficiency?

The research results indicated that the four-phase design achieved 88.18% of the output power of the comparison three-phase motor, with a power factor approaching unity. This suggests that the four-phase motor design could operate close to the rated power of a comparable motor, indicating promising performance characteristics and efficiency gains. Further research is needed to optimize the design and explore its full potential in various applications.