Motor Control Switch Stage for Roller Shutter Without Neutral Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing roller shutter control devices require a neutral connection for operation, which is not available during habitat renovation when replacing manual control switches with remote-controlled devices, posing a challenge in supplying power to the transceiver for remote control without a neutral conductor.
Innovation Solution
A device with a motor control switch stage using phase-cutting of mains voltage, a switching stage for power supply between motor windings, an auxiliary power supply for initial startup, and a control unit for managing power transfers and switch control, allowing discontinuous feeding of the motor and interface power without a neutral connection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a neutral connection is used for powering the control device, then the man-machine interface can be continuously powered, but the device cannot be installed in existing installations during renovation where only phase and motor supply conductors are available
Solution Approach 1:
The patent applies periodic action by feeding the man-machine interface discontinuously during specific time windows within each mains voltage half-period. The interface is powered only when the motor is not actively controlled, utilizing the natural periodic cycles of the AC mains voltage to provide intermittent power supply that accumulates sufficient energy for interface operation.
Solution Approach 2:
The patent employs preliminary action by using an auxiliary power supply activated during startup to ensure the control unit is operational before the main power supply takes over. This preliminary powering allows the system to initialize and detect voltage presence before switching to the discontinuous main power supply mode.
2Adaptability or versatility
If the main power supply feeds through the motor when the shutter is stationary, then the interface can be powered without neutral connection, but the motor impedance may be affected by the continuous current flow
Solution Approach 1:
The patent applies partial action by allowing a low current to flow continuously through the motor when the shutter is stationary, sufficient to power the interface but negligible compared to the motor's impedance rating. This partial current flow provides the necessary power without causing significant voltage drop or interference with motor operation.
3Ease of operation
If the switching stage controls power supply through relay and mechanical contact, then the circuit can be switched between up and down circuits, but the system requires additional components increasing device complexity
Solution Approach 1:
The patent uses a mechanical contact as an intermediary element that can be controlled by a relay to switch between the up and down circuits. The mechanical contact provides reliable circuit switching while being controlled indirectly through the relay, separating the high-current switching function from the low-current control signal.
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 the control of roller shutters and supply of the man-machine interface without a neutral connection, ensuring reliable operation by using phase-cut power supply and auxiliary power for initial startup, with minimal disruption to motor operation.
Implementation Method 1
This comprises a reservoir capacitor charged by the two conductors connected to the motor windings and ensuring the temporary supply of the control unit
Data Source
Figure 1
Figure 2
AI summary
The device has a commutation stage (5) connected between an interrupter stage (1) and conductors (M, D) connected to windings of a motor, for commutating one of the windings in case of interruption of a connection with one of the conductors. A control unit (2) controls the stage (1), and processes supply interruptions and transfers between primary and auxiliary supplies (4, 6), and controls the stage (5). A sector voltage zero passing detection stage (3) sends a synchronization signal to an address of the unit (2) for controlling the stage (1). An independent claim is also included for a method for feeding a motor control device.