Electrical Current Managing System Soft Start Phase Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrical circuits face sudden in-rush currents when turned on, leading to potential circuit failures and the need for oversized breakers and conductors, especially at lower temperatures, due to high current demands from inductive and dynamic loads.
Innovation Solution
The electrical current managing system (ECMS) employs phase control and a soft start mechanism to gradually ramp up the current from zero to full over a two to three second period, using an electronic control circuit, power control relay, silicon controlled rectifier, and AC to DC converter to limit in-rush currents and prevent sudden power surges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional power switch is used to turn on the light bulb, then the light bulb can be illuminated immediately, but a sudden in-rush of current is applied to the filament causing potential circuit failure
Solution Approach 1:
The ECMS applies preliminary action by gradually ramping up the voltage from zero to full operating voltage over a two to three second period before fully energizing the load. This controlled voltage ramp prevents sudden in-rush current while still achieving illumination, resolving the contradiction between immediate operation and circuit protection
Solution Approach 2:
The system employs dynamic voltage control through phase-controlled switching of the SCR, transitioning from a static on/off switch to a dynamic voltage ramping mechanism. The electronic control circuit continuously adjusts the voltage level during the startup period, enabling both fast response and circuit protection
2Reliability
If oversized breakers and conductors are used to handle in-rush current, then circuit reliability is improved, but system cost and complexity increase
Solution Approach 1:
The ECMS changes the voltage parameter dynamically during startup, ramping it from zero to full voltage over two to three seconds. This parameter control allows standard breakers and conductors to handle the load, eliminating the need for oversized components while maintaining circuit reliability
Solution Approach 2:
The electronic control circuit provides feedback control by monitoring the voltage ramp progression and adjusting the SCR firing angle accordingly. This feedback mechanism ensures precise current control during startup, protecting the circuit without requiring oversized protective devices
3Reliability
If phase control with soft start is implemented, then in-rush current is limited and circuit reliability improves, but device complexity increases
Solution Approach 1:
The electronic control circuit performs multiple functions: it controls the SCR phase angle, ramps the voltage, monitors circuit status, and provides protection. This multi-functionality consolidates what would otherwise require separate components into a single integrated control unit, managing complexity while achieving reliable soft start
Solution Approach 2:
The SCR acts as an intermediary device between the power source and the load, enabling phase-controlled voltage ramping. This intermediary component allows precise control of the voltage application to the load, achieving soft start functionality while protecting the circuit from in-rush current
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
This solution prevents circuit failures, allows for larger load installations without oversizing breakers and conductors, reduces electrical consumption, and continuously monitors current, making it cost-effective and reliable.
Implementation Method 1
The ECMS utilizes 'phase control' to set a maximum current draw of an inductive and/or a dynamic load
Implementation Method 2
An AC to DC converter having an input that is applied the a-c voltage from the input power source, and an output that produces a regulated d-c voltage that is applied to the ECC
Data Source
AI summary
An electronic current managing system (ECMS) (10) that utilizes “phase control” to set the maximum current draw of an output load (28) that can consist of an inductive or a dynamic load. The ECMS (10) features a “soft start” that ramps the electric current from zero to full current over a two second period of time. The “soft start” eliminates high in-rush current or power surges from being applied to a system distribution panel or master breaker, thereby allowing a larger output load (28) than would otherwise be possible. The ECMS (10) includes an SCR (22) that causes a power control relay (20) to close or to open in the event the SCR (22) fails and the output load (28) attempts to stay “on”. An example of an ECMS (10) output load (28) is a self regulating cable which has a high in-rush current draw that is approximately three times the rated current per watt.