Solar Powered LED Via Capacitor?

My reseach so far indicates that a 6v 1F cap can light 12ohm LED for approx 8 hours, but I need far more understanding to know if this calculation is correct6 volts and 1 farad is an energy storage of 18 joules ($Ccdot V^2/2$). Spread over 8 hours that's a power of 18/(3600 x 8) watts. So, if you consumed a power of 625 micro watts from your capacitor you would take an energy of 625 micro joules every second and over an hour that would be 2.25 joules and over 8 hours that would be 18 joules.You also need to consider that only about 75% of that energy is usable because as the capacitor voltage droops below 3 volts your LED driver circuit may falter and switch off the LED.It's nowhere near enough for even a standard red LED at 1 mA and 2.0 volts.Any help would be great?Glad to oblige but I would recommend dismantling one of those garden lights to see what they use then scale up your PV panel and battery/supercap accordingly to match your needs.

I am building a large garden peice in wood, which I hope to illumine from within, powered by a small, (perhaps 90x65, 6v, 0.6w 100mA as space is limited) solar panel.

After testing, I noticed that this small power supply is insuficient to even enable a charge controller, let alone charge the USB (1x18650 battery) power stick, I suspect that the current is too low to "wake up" the charge controller?

Whilst considering smaller batteries, or replacing charge controller with a diode, I had a "capacitor" moment, and wondered whether this could be an alternative, if even even better solution?

The ultimate goal is to be able to maintain enough charge during the day to illuminate an LED of any colour (pure white requires a lot more power and pale yellow is more than adequate tho I can use any colours which are more efficient, but I need two of high contrast). I have a photoresistor switch which will also take a little power from the solar panel.

Furthermore... I wondered if a combo cap/battery might work well?

My guess is that this is essentially the same circuit used by a solar garden path/accent light... space within the item is not an issue, only the location for the solar collector mounted on the smallest, topmost panel of the assembly, approx 100mm dia.

My reseach so far indicates that a 6v 1F cap can light 12ohm LED for approx 8 hours, but I need far more understanding to know if this calculation is correct, and am very unsure about the resitance of the LED

Any help would be great?

·OTHER ANSWER:

I am building a large garden peice in wood, which I hope to illumine from within, powered by a small, (perhaps 90x65, 6v, 0.6w 100mA as space is limited) solar panel.

After testing, I noticed that this small power supply is insuficient to even enable a charge controller, let alone charge the USB (1x18650 battery) power stick, I suspect that the current is too low to "wake up" the charge controller?

Whilst considering smaller batteries, or replacing charge controller with a diode, I had a "capacitor" moment, and wondered whether this could be an alternative, if even even better solution?

The ultimate goal is to be able to maintain enough charge during the day to illuminate an LED of any colour (pure white requires a lot more power and pale yellow is more than adequate tho I can use any colours which are more efficient, but I need two of high contrast). I have a photoresistor switch which will also take a little power from the solar panel.

Furthermore... I wondered if a combo cap/battery might work well?

My guess is that this is essentially the same circuit used by a solar garden path/accent light... space within the item is not an issue, only the location for the solar collector mounted on the smallest, topmost panel of the assembly, approx 100mm dia.

My reseach so far indicates that a 6v 1F cap can light 12ohm LED for approx 8 hours, but I need far more understanding to know if this calculation is correct, and am very unsure about the resitance of the LED

Any help would be great?

get in touch with us
추천 기사
Maxim Introduces Offline LED Driver Max16841
key word:LED driver, max16841, Maxim, offlineMaxim Integrated Products, Inc    (NASDAQ: mxim) launched the offline LED driver max16841, which adopts leading edge (three terminal bidirectional thyristor) and trailing edge (transistor) dimmers to realize flicker free dimming from maximum light intensity to zero light intensity. Fixed frequency control optimizes the efficiency of working in low-voltage and high-voltage AC power grids. Max16841 adopts 90vac to 265vac input range, which is a general solution for dimmers in Japan, China, the United States and Europe. The driver allows direct replacement of incandescent and halogen lamps, thus avoiding compatibility problems when pre installing dimmers. Max16841 can work without electrolytic capacitor, thus prolonging the service life of LED lamp. Eliminating these capacitors can also save space and cost. The LED driver is very suitable for the upgrading of dimmable LED lamps and general LED lamps in industrial, commercial and residential lighting applications.Dimming problems in upgrading applicationsThe dimmer increases or decreases the transmitted light intensity by increasing or decreasing the power supply of the lamp. Now, the two most common voltage regulation methods are leading edge (three terminal bidirectional thyristor) and trailing edge (transistor) dimmers. Both types of dimmers adjust the power of the lamp by cutting off part of the AC waveform. As the name suggests, the leading edge dimmer cuts the leading edge after the waveform crosses zero, and the trailing edge dimmer cuts the part before the waveform crosses zero. The leading edge dimmer is suitable for resistive or inductive loads, and the trailing edge dimmer is suitable for resistive or capacitive loads.In order to directly upgrade the traditional lighting, LED lamps must be compatible with front and rear edge dimmers at the same time. These dimmer designs are usually suitable for traditional halogen and incandescent resistive loads. However, the LED driver is completely nonlinear and is not suitable for the pure resistive load of the dimmer. Therefore, when the LED is connected to an existing electrical facility with a dimmer, the LED usually flashes and often darkens, and in some cases it does not even light at all.Max16841 uses patented technology to control the input current of the lighting lamp to solve this problem. By actively correcting the input current, the driver ensures no flicker and works in most electronic transformers and dimmers. Now, LED lamp designers can design replacement products that directly replace halogen lamps and incandescent lamps with adjustable light intensity to zero.Flexible design optimizes efficiency under any operating conditionsMax16841 can be designed in isolated (flyback) and non isolated (step-down) configurations, suitable for both high-voltage AC power grid (220VAC to 230VAC) and low-voltage AC power grid (100vac to 120VAC). The fixed frequency control architecture selects the optimal conduction mode (DCM or CCM) according to the input voltage, so as to improve the efficiency. Since the regulator itself can ensure sufficient holding current when switching, max16841 current control technology does not need a shunt to maintain the dimmer current, so as to improve the dimming efficiency.Universal input expands the application field, shortens the design time and reduces the costThe max16841 can be configured as a universal input (90vac to 265vac) for flicker free dimming in newer applications worldwide. The max16841 also reduces inventory and design costs because it can meet global voltage requirements without a separate LED driver.Prolong lamp life and save spaceMax16841 can be designed not to use electrolytic capacitors. Electrolytic capacitor is usually the most fault prone component of driver circuit, so it prolongs the service life of LED lamp. If electrolytic capacitors are used in existing designs, the max16841 can continue to maintain normal lighting even when these capacitors fail.Eliminating the electrolytic capacitor can also reduce the cost of the driver and reduce the volume, which is suitable for small volume applications.   More detailsMax16841 operates in the temperature range of - 40 ° C to 125 ° C. 8-pin, SOIC package.2011-10-17 13:07:27 uploadDownload attachment (10.68 KB)
Design of LED Driver Circuit Based on a High Efficiency
Best Practice for Wiring an LED Driver to the Lighting Circuit
Application Analysis of Power Supply Applied to LED Driver
Lt3922 Low EMI LED Driver Meets the Design Requirements of LED System
Troubleshooting Defective LED Bulbs
Application of White LED Driver Cat3636 in Portable Equipment
Power Pc Fan Using Led Driver: 3 Steps - Instructables.com
LED Driver Power Supply Solution - MEAN WELL
10 Problems That Can Cause Led Driver Failure (Part 3)
related searches
Troubleshooting Defective LED Bulbs
When Performing an LED Retrofit on T8 Fluorescents, Is It Better to Direct Wire, Replace the Ballast
Deco 90C Watt-Controlled Drivers Outperform the Competition
Portable High Lumens Array Closed
What Is the Driver of the Led Light
Is the OPA860 a Diamond Transistor?
Connecting KY-009 to GPIO of Raspberry Pi
Dimmer Rotation Span Wider Than the Light Intensity Span
Arduino, Best Way to Talk with Multiple SPI Devices (LED Drivers)

Copyright © 2020  Shandong Abusair Agricultural Machinery Co,. Ltd- |  Sitemap

Multifunctional farm Abusair machinery  |  Tea Professional Cultivator farm machinery