SiC Solid-State Switches for Elevator Power Output Stage Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing elevator systems experience noise disturbances and reduced service life due to high switching frequency in IGBT transistors, which increases power losses and overheating, making it costly and space-inefficient to increase switching frequency to reduce noise.
Innovation Solution
Employing silicon carbide (SiC) solid-state switches with higher electron speed and lower energy bandwidth, allowing for increased switching frequency without excessive switching losses, and using a reduced cooling apparatus due to SiC's better thermal conductivity, enabling a more compact and efficient power output stage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the switching frequency of IGBT transistors is increased to reduce noise, then noise levels are reduced, but switching losses increase causing overheating and reduced service life
Solution Approach 1:
The patent changes the material parameter of the solid-state switches from conventional silicon-based IGBT transistors to silicon carbide (SiC) transistors. This material parameter change enables higher switching frequencies (20-50 kHz or higher) with significantly reduced switching losses, as SiC transistors have lower on-resistance and faster switching characteristics, thereby resolving the contradiction between noise reduction and energy loss.
2Object-affected harmful factors
If the switching frequency is increased to reduce noise, then noise levels are reduced, but the service life of frequency converters is shortened due to overheating
Solution Approach 1:
The patent changes the material parameter from conventional IGBT transistors to silicon carbide (SiC) transistors, which have superior thermal conductivity and lower switching losses. This enables operation at higher switching frequencies (20-50 kHz or higher) without excessive heat generation, thereby reducing noise while maintaining or extending the service life of the frequency converter.
3Object-affected harmful factors
If the IGBT transistors are overdimensioned to enable higher switching frequency, then noise is reduced, but the size and cost of the frequency converter increases
Solution Approach 1:
The patent changes the material parameter to silicon carbide (SiC) transistors, which inherently support higher switching frequencies without requiring oversized components. The SiC transistors' lower on-resistance and faster switching capability allow operation at 20-50 kHz or higher with compact dimensions, avoiding the need for overdimensioning and reducing both size and cost.
4Object-affected harmful factors
If the IGBT transistors are overdimensioned to enable higher switching frequency, then noise is reduced, but the cost of the frequency converter increases
Solution Approach 1:
The patent changes the material parameter from conventional IGBT transistors to silicon carbide (SiC) transistors. Although SiC transistors have higher unit cost, the patent eliminates the need for overdimensioning and associated excess materials, cooling apparatus, and assembly complexity. The compact design enabled by SiC's superior properties reduces overall manufacturing cost while achieving noise reduction at higher switching frequencies.
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
The solution significantly reduces noise levels by increasing switching frequency beyond human hearing range, extends the service life of frequency converters, and enhances space efficiency by minimizing the size of the electricity supply device.
Implementation Method 1
the speed of travel of the electrons in a silicon carbide semiconductor is greater than in conventional power semiconductors, which reduces the switching losses of the silicon carbide power semiconductor
Implementation Method 2
silicon carbide semiconductors have better thermal conductivity as well as smaller losses, and especially smaller switching losses, than conventional semiconductors
Implementation Method 3
silicon carbide semiconductors have better thermal conductivity
Implementation Method 4
the dimensioning of the cooling apparatus of the power output stage comprising a silicon carbide semiconductor/silicon carbide semiconductors can be reduced
Data Source
Figure 1
Figure 2a~2b
Figure 3
AI summary
The invention relates to an elevator system and also to an electricity supply device (1, 2, 3) for supplying electric power in the elevator system. The electricity supply device (1, 2, 3) comprises a controllable power output stage (4, 5), comprising a connection to the load (6, 7, 8) of the elevator system to be supplied. The power output stage (4, 5) comprises one or more controllable solid-state switches (9) in the form of silicon carbide (SiC) solid-state switches.