Durable Toroidal Iron Core for Enhanced Electric Transformer Performance

Toroidal Iron Core Product Description

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Toroidal Iron Core Characteristics

High Magnetic Circuit Efficiency: The toroidal structure creates a fully closed magnetic circuit, free of seams or air gaps found in traditional laminated cores. The magnetic field can conduct smoothly along the toroid, resulting in much lower magnetic resistance than non-toroidal cores (e.g., bar-shaped, U-shaped). This minimizes magnetic energy leakage and improves magnetic circuit efficiency by 10%-30%.

 

Low Energy Loss: The closed magnetic circuit reduces hysteresis loss caused by sudden changes in magnetic resistance. When combined with low-loss magnetic materials (such as silicon steel or amorphous alloys), the overall energy loss (especially no-load loss) is significantly lower than that of non-toroidal cores, meeting high-efficiency and energy-saving requirements.

 

Strong Operational Stability: The toroidal structure has good mechanical balance, leading to small vibration amplitude and low operating noise (5-15dB lower than traditional laminated cores) under alternating magnetic fields. Additionally, its magnetic properties are evenly distributed, preventing local magnetic saturation and ensuring long-term stable operation of equipment.

 

Main Material Classifications and Applicable Scenarios

The performance and application of a toroidal iron core are mainly determined by its base material. Common classifications and their applications are as follows:

 

Soft Iron Toroidal Core:

Made of pure iron or low-carbon soft iron. It has high magnetic permeability and low cost but relatively high high-frequency loss. It is suitable for low-frequency scenarios (e.g., power-frequency transformers, small inductors).

 

Silicon Steel Toroidal Core:

Made of silicon-containing low-carbon steel (grain-oriented or non-grain-oriented silicon steel). It features low iron loss and stable magnetic properties, making it the main choice for medium-to-low frequency fields (e.g., distribution transformers, iron cores for home appliance motors).

 

Amorphous/Nanocrystalline Alloy Toroidal Core:

Made of amorphous alloys (e.g., iron-silicon-boron alloys) or nanocrystalline alloys. It has ultra-low loss and high saturation magnetic flux density, suitable for high-frequency and high-efficiency scenarios (e.g., new energy on-board transformers, high-frequency inductors).

 

Typical Manufacturing Processes

The manufacturing of toroidal iron cores must match the material properties, with two core processes:

 

• Winding Process: Continuous magnetic material strips (e.g., silicon steel strips, amorphous alloy strips) are wound into a toroidal shape using specialized equipment, followed by annealing (to eliminate internal stress) and curing for final forming. This process produces seamless cores with optimal magnetic properties, suitable for scenarios requiring low loss (e.g., high-efficiency transformers).

 

• Lamination Process: Magnetic materials are cut into fan-shaped or arc-shaped pieces, which are then laminated and spliced into a toroidal shape, followed by fixing and annealing. This process offers high flexibility, allowing the production of large-sized or specially shaped toroidal cores. However, it results in a small number of seams, leading to slightly inferior magnetic properties compared to the winding process.

 

Core Differences from Traditional Laminated Cores

Compared with the widely used rectangular laminated cores, the advantages of toroidal cores focus on magnetic circuits and energy consumption, with specific comparisons as follows:

 

Magnetic Circuit and Loss: Toroidal cores have a closed magnetic circuit and no seams, resulting in low magnetic resistance and low loss. Laminated cores have multiple seams and air gaps, leading to more magnetic energy leakage and higher loss.

 

Size and Weight: For the same power, toroidal cores have higher magnetic circuit efficiency, allowing a 20%-40% reduction in size and a 15%-30% reduction in weight. This better meets the demand for equipment miniaturization.

 

Noise and Cost: Toroidal cores have small vibration and low noise. However, their manufacturing process is complex (especially the winding process), leading to a 10%-50% higher cost than ordinary laminated cores.

ring core specification

Magnetic core size(mm)			Protective box size(mm)			Effective cross-sectional area Ae(mm2)		Magnetic path length Ie(mm)		Maximum DC overcurrent class (A)
id	od	ht	ID	OD	HT
14	19	6.5	12	22	8	11.86		51.81		20
14	20	10	12	22.3	11.4	29.68		52.29		40
16	21	10	15	24	12.3	24.85		57.41		60
16	23	8	15	24	9.7	20.44		61.23		60
16	23	10	15	24	12.3	34.62		59.92		60
17	22	10	15.3	24.4	12.3	24.86		60.59		60
17	21	8	15.3	24	9.7	25.56		60.67		60
17	23	8	15.3	24.4	9.7	26.89		61.34		60
18	23	10	16.4	24.4	12.3	29.78		60.38		70
18	24	9	16.4	25	11.2	34.78		60.89		70
18	25	10	16.4	25.9	12.3	37.97		64.56		70
19	24	9	17.3	25	11.2	40.39		65.32		80
19	25	10	17.3	26	12.3	39.42		62.31		80
19	26	10	17.3	27.3	12.3	48.32		69.56		80
20	25	10	18.5	26.3	12.3	39.29		70.32		90
20	28	10	18.5	29	12.3	45.76		73.88		90
20	32	10	18.5	32.3	12.3	58.91		78.75		90
21	29	10	18.2	31.3	12.3	39.65		77.19		100
21	26	8	18.3	27.4	9.7	46.54		78.32		100
21	28	10	18.3	30	12.3	50.39		77.45		100
22	28	10	20.5	30	12.3	49.32		79.89		120
22	32	10	20.5	33.4	12.3	43.58		73.43		120
23	32	10	21.3	33.4	12.3	44.56		74.56		120