Non-through Rotor Mechanical Drive System for High-Speed Compressors

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing mechanical drive systems with rotating electrical machines featuring a through rotor are limited by high mass, size, and efficiency due to the need for coupling shafts and flexible coupling devices, which also restrict peripheral speed and torque transmission.

Innovation Solution

A mechanical drive system with a non-through rotor comprising a cylindrical magnetic mass sandwiched between two half-shafts, integrated with a transfer box and toothed wheels, eliminating the need for coupling shafts and flexible couplings, allowing for reduced mass, increased speed, and enhanced efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a through shaft is used in the rotor, then the structural simplicity is improved, but the peripheral speed is limited to 200 m/s due to excessive stresses in the magnetic mass under centrifugal force

Engineering Contradiction:

Improvestructural simplicityVSAvoidperipheral speed

Core Design Contradiction:

Device complexityVSSpeed

Solution Approach 1:

The rotor shaft is divided into two half-shafts that do not traverse through the magnetic mass. The half-shafts are positioned at opposite ends of the cylindrical magnetic mass and are coupled together, eliminating the need for a through shaft and allowing peripheral speeds greater than 200 m/s without excessive centrifugal stresses.

Inventive Principle:

Principle #1Segmentation

2Force

If coupling shafts and flexible coupling devices are integrated, then the torque transmission capability is improved, but the system mass and size increase

Engineering Contradiction:

Improvetorque transmission capabilityVSAvoidsystem mass

Core Design Contradiction:

ForceVSWeight of moving object

Solution Approach 1:

The coupling shaft and flexible coupling devices are completely removed from the system. Instead, the half-shafts are directly coupled at their free ends to the input shaft of the transfer box, eliminating the need for separate coupling components and reducing system mass.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The function of the coupling shaft and flexible coupling devices is merged into a direct coupling between the half-shafts and the input shaft. This integration eliminates intermediate components while maintaining torque transmission capability.

Inventive Principle:

Principle #5Merging (Combining)

3Force

If coupling shafts and flexible coupling devices are integrated, then the torque transmission capability is improved, but the system size increases in the axial direction

Engineering Contradiction:

Improvetorque transmission capabilityVSAvoidaxial dimension

Core Design Contradiction:

ForceVSLength of moving object

Solution Approach 1:

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Inventive Principle:

Principle #5Merging (Combining)

4Reliability

If flexible coupling devices are used, then the compensation for thermal expansion and coaxiality defects is improved, but energy dissipation increases and overall efficiency decreases

Engineering Contradiction:

Improvecompensation for thermal expansion and coaxiality defectsVSAvoidenergy dissipation

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The flexible coupling devices are completely removed from the system. The half-shafts are directly coupled at their free ends to the input shaft, eliminating the flexible coupling components that cause energy dissipation.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The half-shafts themselves provide the coupling function through their free ends, eliminating the need for separate flexible coupling devices. The system uses its own structural components (half-shafts) to perform the coupling function, reducing energy losses.

Inventive Principle:

Principle #25Self-service

5Ease of manufacture

If a hollow rotor shaft is used, then the manufacturing ease is improved, but the torque transmission capability is limited

Engineering Contradiction:

Improvemanufacturing easeVSAvoidtorque transmission capability

Core Design Contradiction:

Ease of manufactureVSForce

Solution Approach 1:

The rotor shaft is segmented into two solid half-shafts positioned at opposite ends of the magnetic mass. Each half-shaft is solid rather than hollow, providing high torque transmission capability while being manufacturable as separate components that are coupled together.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentEP3911872B1Mechanical drive system and associated motor compressor

Publication Date: 2023.03.01 GE ENERGY POWER CONVERSION TECHNOLOGY LTD(GB)

Figure 1
Figure 2
Figure 3~4

AI summary

The invention relates to a mechanical drive system (20) comprising a frame (21), at least one rotating electrical machine (22) having a rotor with a non-through shaft (25) disposed on the frame, and at least one transfer box (23) comprising at least one driving gearwheel (37). The driving gearwheel is secured to a rotor shaft of the rotating electrical machine, the transfer box being disposed on the frame.