Coreless Generator Double Magnetic Circuits
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Solution Overview
Problem
Conventional permanent magnetic generators suffer from hysteresis and eddy current resistances due to silicon steel sheet core structures, leading to reduced energy conversion efficiency and heat energy consumption, while coreless generators lack magnetic permeability, resulting in lower magnetic field density.
Innovation Solution
A rare-earth permanent-magnetic axial coreless generator with double magnetic circuits is designed, featuring a coreless stator winding between an inner and outer rotor structure, allowing simultaneous cutting of rotating magnetic fields from both rotors to enhance power generation capacity without silicon steel sheet cores.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a silicon steel sheet core structure is used in the stator winding, then the magnetic field density is improved, but hysteresis resistance and eddy current resistance are generated causing heat energy consumption and reduced energy conversion efficiency
Solution Approach 1:
The invention divides the magnetic circuit into two separate parts: an inner rotor with permanent magnets and an outer rotor with electromagnetic windings. This segmentation allows the magnetic field generation and energy conversion to occur in distinct zones, eliminating the need for a silicon steel sheet core in the stator and thereby removing the source of hysteresis and eddy current losses while maintaining magnetic field density through the dual-rotor configuration
Solution Approach 2:
The invention extracts and removes the silicon steel sheet core from the stator structure, replacing it with a coreless design. This extraction eliminates the harmful hysteresis and eddy current effects associated with ferromagnetic materials while the magnetic field density is compensated by the dual-rotor permanent magnet configuration, which creates a stronger overall magnetic field
2Loss of energy
If a coreless stator winding structure is used, then hysteresis and eddy current resistances are eliminated improving energy conversion efficiency, but the magnetic field density is reduced
Solution Approach 1:
The invention merges two rotor structures (inner rotor and outer rotor) with permanent magnets into a single generator system. This combination creates a dual magnetic field that penetrates through the coreless stator winding, compensating for the reduced magnetic field density that would otherwise result from removing the silicon steel sheet core, while maintaining the high energy conversion efficiency of the coreless design
Solution Approach 2:
The invention uses rare-earth permanent magnets in both the inner and outer rotors to create a composite magnetic circuit. This composite structure, consisting of two permanent magnet systems working together, generates a sufficiently dense magnetic field that compensates for the absence of ferromagnetic core materials, thereby maintaining magnetic field density without sacrificing energy conversion efficiency
3Device complexity
If only one permanent magnet rotor structure is used, then the device complexity is reduced, but the power generation capacity is limited
Solution Approach 1:
The invention transitions from a single-rotor configuration to a dual-rotor configuration, adding a spatial dimension to the magnetic circuit. The inner rotor and outer rotor are arranged concentrically, creating two separate air gaps and two independent magnetic fields that both contribute to power generation. This dimensional change effectively doubles the power generation capacity without proportionally increasing device complexity
Solution Approach 2:
The invention employs a nested configuration where the inner rotor with permanent magnets is placed inside the outer rotor with electromagnetic windings. This nesting arrangement allows both rotors to share the same stator structure and magnetic circuit path, effectively doubling the power generation capacity while minimizing the increase in overall device size and complexity through space-efficient utilization
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design increases power generation capacity by eliminating hysteresis and eddy current resistances and heat energy consumption, while maintaining high energy conversion efficiency through the use of double magnetic circuits.
Implementation Method 1
the coreless stator winding can simultaneously cut the magnetic force lines of the rotating magnetic field with double magnetic circuits formed by the outer rotor structure and the inner rotor structure by using contact surfaces inside and outside the winding, thereby increasing the power generating capacity of the generator
Data Source
AI summary
Disclosed a rare-earth permanent-magnetic axial coreless generator with double magnetic circuits, including a main shaft, a coreless stator winding, an inner rotor structure connected with the main shaft and an outer rotor structure. The outer rotor structure and the inner rotor structure are spaced apart by the coreless stator winding and are connected with the main shaft; the coreless stator winding is arranged between the inner rotor structure and the outer rotor structure, to establish a generator structure with two magnetic field air gaps; when the main shaft drives the outer rotor structure and the inner rotor structure to rotate simultaneously under the action of an external force, a rotating magnetic field with double magnetic circuits is generated in the generator; and the coreless stator winding can simultaneously cut magnetic lines of the rotating magnetic field with double magnetic circuits by using contact surfaces inside and outside the winding.