Elevator Controller Internal Power Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Elevator systems are dependent on external power sources, making them unreliable when power is unavailable, especially in machine room-less systems where a separate power source is not housed.
Innovation Solution
A controller is used to manage an internal power source, switching between motoring, near balance, and regenerative modes to maintain elevator operation and control, allowing the system to transition to an internal power source when external power is lost, and adjust velocity to bring the elevator to a controlled stop.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the elevator system uses an external power source, then the system can operate normally under standard conditions, but the system becomes unreliable when external power is unavailable
Solution Approach 1:
The elevator system incorporates an internal power source (battery) that enables the system to serve itself when external power is unavailable. The controller detects power loss and automatically switches to internal power, allowing the elevator to complete its current trip and return to the home position without external power assistance.
Solution Approach 2:
The power supply system is designed to accept multiple power sources - both external power and internal battery power. The controller universally manages both power sources, switching between them based on availability, making the power supply system adaptable to different operating conditions.
2Reliability
If the system switches to internal power source, then the elevator can continue operation during power outage, but the internal power source has limited energy capacity
Solution Approach 1:
The system uses the internal power source partially - only for the duration needed to complete the current trip and return to home position. It does not attempt to sustain full operation indefinitely, but rather provides enough energy to get the elevator to a safe state where it can be serviced or external power restored.
Solution Approach 2:
The battery is pre-charged during normal operation when external power is available. This preliminary energy storage allows the system to immediately switch to internal power without interruption when external power fails, ensuring continuous operation.
3Adaptability or versatility
If the controller manages multiple operating modes, then the system can optimize performance for different conditions, but the control system becomes more complex
Solution Approach 1:
The controller dynamically adjusts its control strategy based on the detected operating mode and power source availability. It automatically transitions between motoring mode, near balance mode, and regenerative braking mode, and manages switching between external and internal power sources, adapting its behavior to current conditions without requiring manual intervention.
4Device complexity
If the elevator operates in machine room-less system, then the system structure is simplified, but there is no separate space to house backup power equipment
Solution Approach 1:
The drive unit and power conversion device are merged into the hoistway structure, eliminating the separate machine room. The internal power source is integrated with the drive unit, combining the motor and power supply functions in one location within the hoistway, maintaining structural simplicity while providing backup power capability.
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
Enables a controlled stop of the elevator car when external power is unavailable, ensuring safe operation and efficient use of internal power sources by seamlessly transitioning power and adjusting velocity according to detected modes.
Implementation Method 1
an internal power source (18)
Implementation Method 2
a power conversion device (21)
Implementation Method 3
a brake (24)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of operating an elevator system (10) is presented. The method comprises controlling, using a controller (30), a plurality of components of the elevator system (10). The controlling comprises operating at least one of an internal power source (18), an elevator car (23), a drive unit (20), a power conversion device, and a brake (24). The method also comprises detecting, using the controller (30), when an external power source (12) is unavailable; deactivating, using the controller, the power conversion device when an external power source (12) is unavailable; and determining, using the controller (30), a mode of the elevator car (23). The mode includes at least one of a motoring mode and a near balance mode. The method further comprises connecting, using the controller (30), to an internal power source (18), when at least one of the motoring mode and the near balance mode is determined; and increasing, using the internal power source (18), voltage of the drive unit (20).