Solusyon ng Intelligent Control Module para sa Voltage Sag Ride-Through ng AC Contactor
1. Disenyo ng Background at Pagsusuri ng Pangangailangan
Sa pag-operate ng sistema ng kuryente, ang mga voltage sag—na may karakter na biglang pagbaba ng RMS voltage sa 10%–90% ng rated value na tumatagal mula 10 ms hanggang 1 minuto—madalas nangyayari dahil sa lightning strikes, short-circuit faults, o pagsisimula ng malaking equipment. Ang mga pangyayaring ito ay maaaring magresulta sa pag-trip ng traditional AC contactors, na nagdudulot ng hindi inaasahang pagtigil sa continuous production processes at malaking economic losses.
Kahit na ilang intelligent control solutions (halimbawa, high-voltage DC starting, PWM control) ang ipinroporsyon, may isang pangunahing limitasyon pa rin: ang pagkakakulang na i-integrate ang automatic module fault transition functionality kasama ang voltage sag ride-through capability. Upang tugunan itong isyu, ang solusyon na ito ay gumagamit ng CDC17-115 AC contactor bilang target ng kontrol at ginawa ang isang intelligent control module na may fault redundancy upang panatilihin ang patuloy na produksyon kahit na may pagkakamali sa module.
2. Prinsipyong Paggana ng Module at System Design
2.1 Kabuuang Operational Logic Architecture
Ang intelligent control module ay gumagamit ng dual-mode power supply design upang matiyak ang reliable operation sa iba't ibang kondisyon:
|
Operating State |
Power Supply Method |
Core Function |
Trigger Condition |
|
Normal Operation |
DC Supply (via control module) |
Silent DC operation, voltage sag ride-through |
Fault protection circuit detects no abnormality |
|
Module Fault |
AC Supply (via contact switch) |
Maintain production, issue alarm signal |
Electronic circuit fault or coil DC under-voltage |
|
Voltage Sag |
Activate ride-through function |
Maintain contactor pull-in state |
Sampled voltage drops below 60% of rated value |
|
Voltage Recovery |
Deactivate ride-through function |
Resume normal low-voltage holding |
Voltage recovers within n ms (adjustable) |
|
Voltage Not Recovered |
Contactor breaks |
Safe shutdown |
Voltage sag exceeds n ms without recovery |
2.2 Mga Detalye ng Teknikal na Component
2.2.1 Switching Power Supply Design
Ang high-performance switching power supply ay nagsisilbing core power unit na may sumusunod na katangian:
- Core Architecture: Pulse-width modulation IC (switching frequency 132 kHz), MOSFET (MTD1N80E), special transformer (primary inductance 900 μH, leakage inductance 15 μH, turns ratio 0.11), at π-type output filter (L3, C2, C3)
- Multi-Protection Functions: Input overvoltage/undervoltage, output overvoltage/overcurrent/short-circuit/overheat protection, integrated soft-start and frequency jitter technology
- Performance:
- Stable load start-up time < 35 ms, supports rapid switching between ride-through and normal states
- Automatically limits power during short circuits and quickly stabilizes after fault clearance
- Triggers overvoltage protection and immediately shuts off PWM output upon feedback loop open
Table 1: Impact of Filter Parasitic Parameters on Short-Circuit Recovery Voltage
|
Simulation Condition |
R4/mΩ |
R3/mΩ |
R5/mΩ |
Umax/V |
Umin/V |
|
Only varying filter capacitor parasitic resistance |
10 |
100 |
300 |
14.78 |
7.41 |
|
Only varying filter capacitor parasitic resistance |
10 |
20 |
70 |
8.89 |
4.79 |
|
Only varying filter inductor parasitic resistance |
10 |
100 |
300 |
14.78 |
7.41 |
|
Only varying filter inductor parasitic resistance |
800 |
100 |
300 |
6.11 |
6.06 |
2.2.2 Fault Transition Circuit Design
Ang isang bagong kombinasyon ng contact at contactless switches ang ginamit:
- Structural Design: Ang contact switches ay naghahandle ng full breaking at isolation functions para sa high-power switching; ang power electronic switches ay nagbibigay ng arc-free, high-frequency operation
- Intelligent Transition Logic:
- Ang AC power ay na-supply via normally closed contacts sa initial power-up
- Awtomatikong lumilipat sa DC supply mode sa normal operation
- Pagka-detekta ng fault, deactivates ang contact switch drive; resumes AC direct supply pagkatapos ng reset upang matiyak ang continuity
- Contact Protection Technology: Gumagamit ng universal AC/DC absorption suppression circuit (diode RC + bidirectional TVS diode D3) upang mabawasan ang overvoltage, dissipate ang inductive magnetic energy, at mabawasan ang arcing
2.2.3 Transition Process Optimization
- AC-to-DC Transition: Nag-apply ng full-wave rectified pulsating voltage via power electronic switches, delayed 10 ms bago lumipat sa low-voltage DC, na mabisa na nagpapahinto sa core rebound; pinagsubok na smooth at walang vibration ang transition
- DC-to-AC Transition: Pinutol ang DC pagka-detekta ng fault at awtomatikong idine-introduce ang AC supply; ang arc energy ay iniiwasan sa pamamagitan ng reverse diodes sa transition, na may phase-angle control upang iwasan ang voltage spike interference
- Parameter Optimization (based on simulation results):
- Resistors (R2, R3): Mas maliit na resistance values ay nagreresulta sa mas mabagal na decay ng amplitude ng voltage ngunit hindi nakakaapekto sa transition phase angle
- Capacitors (C1, C2): Mas maliit na capacitance values ay nagreresulta sa mas mataas na oscillation decay frequency (f = 174.7 Hz at C = 2 μF; f = 795.4 Hz at C = 0.1 μF)
3. Simulation at Experimental Verification
3.1 Simulation Analysis
Ang mga system simulations ay isinagawa gamit ang Multisim software, kabilang dito:
- Switching power supply start-up characteristics and protection performance simulation
- Analysis of resistance, capacitance, and phase angle effects on voltage oscillation during transition
- Evaluation of parasitic parameter impacts on system stability
3.2 Experimental Verification
Ang mga test sa CDC17-115 AC contactor ay napatunayan:
- Ang switching power supply no-load/full-load (50 A contactor) waveforms ay sumasalamin sa design expectations
- Ang protection mechanisms ay mabilis at mabisa sa short-circuit/feedback open-circuit faults
- Ang transition processes ay smooth, walang core vibration, at lahat ng functions ay sumasalamin sa design requirements
4. Core Advantages at Conclusion
- High-Performance Switching Power Supply: Compact size, high efficiency, at comprehensive protection functions na malaki ang kontribusyon sa electrical reliability, na ideyal para sa smart electrical applications.
- Intelligent Fault Transition: Bagong disenyo na naglalaman ng contact at contactless switches na nag-uugnay upang maipaglaban ang AC operation sa panahon ng module faults, na nagpapatibay sa continuous power supply sa contactor system.
- Efficient Energy Management: Universal AC/DC absorption suppression circuit na mabisa sa pag-convert ng overvoltage at arc energy sa stable electromagnetic force, na nagpapatibay sa uninterrupted production.
- Voltage Sag Ride-Through Capability: Awtomatikong aktibo kapag ang system voltage ay bumaba sa 60% ng rated value, na nagpapanatili ng reliable contactor pull-in upang iwasan ang unplanned shutdowns.
Ang solusyon na ito ay matagumpay na nag-integrate ng module fault transition kasama ang voltage sag ride-through functionality, na nagbibigay ng mataas na reliable power assurance solution para sa continuous production processes at epektibong nag-iwas sa downtime dahil sa voltage sags.
