Centralized Drive System Safety Circuit for Safe Torque-Off
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive systems with decentralized safety functions for electric motors are costly and labor-intensive due to the need for individual motor converters and complex wiring, making it difficult to implement a reliable and centrally controlled safe torque-off function.
Innovation Solution
A method and system for safely switching off a drive system using a centrally controlled safety function, where a connecting and disconnecting circuit interrupts the intermediate circuit voltage, allowing for a simple and cost-effective shutdown of multiple electric motors through a control unit, reducing assembly and wiring efforts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If decentralized safety functions are implemented in individual motor converters, then reliable safe torque-off function is achieved, but production costs and assembly complexity increase significantly
Solution Approach 1:
The patent merges the safety function from decentralized motor converters into a single centralized disconnecting circuit in the converter. Instead of each motor converter having its own safety mechanism, the invention combines all safety functions into one central location that can control power distribution to multiple motors, thereby reducing assembly complexity while maintaining reliability
Solution Approach 2:
The centralized disconnecting circuit serves multiple functions: it provides safe torque-off capability for all motors, acts as a central power distribution control, and enables simplified wiring architecture. This multi-functional design eliminates the need for separate safety circuits in each motor converter
2Reliability
If decentralized safety functions are implemented in individual motor converters, then reliable safe torque-off function is achieved, but production costs increase
Solution Approach 1:
By combining safety functions into a single centralized circuit rather than duplicating safety mechanisms in each motor converter, the invention reduces the total number of components required. This consolidation lowers production costs through reduced component count, simplified manufacturing processes, and decreased wiring material requirements
Solution Approach 2:
The centralized disconnecting circuit provides universal safety control for all motors in the system, eliminating the need for multiple specialized safety circuits. This universal approach reduces production costs by standardizing the safety function across the entire drive system
3Ease of manufacture
If centralized control is implemented by interrupting the intermediate circuit, then assembly effort is reduced, but control of multiple motors must be coordinated
Solution Approach 1:
The invention extracts the safety control function from the motor converter level and moves it to the converter level. By taking out the disconnecting circuit from individual motor controls and placing it in the central converter, the patent simplifies assembly while the control unit naturally handles coordination of multiple motors through centralized power distribution control
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The invention relates to a method for safely switching off a drive system (2) with a converter (6) connected to a supply network (12) with a DC intermediate circuit (16) for providing an intermediate circuit voltage (DCV) for a number of electric motors (4) each with a motor converter (8) connected to the intermediate circuit (16), and with a switched control unit (28), wherein the control unit (28) safely interrupts the intermediate circuit (16) on the basis of a switch-off signal (A, A1, A2).