Ship Propulsion Machine Inverter Mounting Strategy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ship propulsion machines with AC motors and inverters face challenges in size and weight, leading to increased motor cover and ship propulsion machine sizes due to the need for robust support structures for the heavy inverter and motor.
Innovation Solution
The ship propulsion machine design includes a motor with a lower and upper motor bracket, where the inverter is attached to both brackets, allowing it to be supported by the motor and a motor holder, thereby concentrating the components in a smaller area and reducing the need for a larger motor holder.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the motor and inverter are distributed and supported on the bottom portion of the motor cover, then the support strength is improved, but the size of the motor cover and ship propulsion machine increases
Solution Approach 1:
The inverter is attached not only to the bottom portion but also to the side portion of the motor cover, utilizing a second spatial dimension. This distributes the support load across multiple surfaces (bottom and side) rather than concentrating it on the bottom alone, thereby maintaining support strength while preventing excessive increase in motor cover size
2Strength
If the motor and inverter are distributed and supported on the bottom portion of the motor cover, then the support strength is improved, but the weight of the ship propulsion machine increases
Solution Approach 1:
The attachment structure is segmented into multiple locations (bottom portion and side portion) rather than using a single large high-rigidity base. This distributes the weight-bearing function across multiple smaller attachment points, reducing the need for excessive material and overall weight while maintaining sufficient support strength
3Strength
If a large high-rigidity base is provided to support the motor and inverter, then the support strength is improved, but the size of the motor cover increases
Solution Approach 1:
Instead of expanding the bottom area with a large base, the solution utilizes the side portion of the motor cover for attachment. This transitions from a two-dimensional bottom-area expansion to a three-dimensional multi-surface utilization, maintaining support strength without increasing the horizontal footprint of the motor cover
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A ship propulsion machine (1) includes: a motor (3); an inverter (14) configured to generate a driving current for controlling drive of the motor; a propeller (25); and a power transmission mechanism (26, 27, 28) configured to transmit power of the motor to the propeller. The motor includes: a motor shaft (4); a rotor (5); a stator (6); a motor housing (7) in which the motor shaft, the rotor, and the stator provided are housed; a lower motor bracket (8) to which a lower portion of the motor housing is fixed; and an upper motor bracket (11) to which an upper portion of the motor housing is fixed. A lower portion of the inverter is attached to the lower motor bracket, and an upper portion of the inverter is attached to the upper motor bracket.