Tuesday, March 18, 2014

LED Lighting - The Future is Here

LED Lighting is more important than you think it is. Start Using Alternative Energy, like Wind Power and Solar, Tidal and even Magmatic.

LED Lighting at Wikipedia

On September 24, 2009 the DOE announced that Philips Lighting North America was the first to submit lamps in the category to replace the standard 60 W A-19 "Edison screw fixture" light bulb, with a design based on their earlier "EnduraLED" consumer product.

LED Lighting - The Future is Here

On August 3, 2011, DOE awarded the prize in the 60 W replacement category to Philips bulb after 18 months of extensive testing. The 10-W, 900-lumen Philips bulb was made available to consumers in April 2012.

The same day, CREE demonstrated a prototype lamp producing 1330 lumens with a mere 8.7 W of input power. While the CREE lamp has not undergone DOE reliability testing and no commercial release date was promised, it is an indication that the "21st Century Lamp" performance levels may soon be within reach of commercial products.

Highly efficient LED Bulb Driver - Infineon

The highly efficient dimmable LED driver system utilizing ICL8001G sets a new Benchmark with respect to integration, performance, features and total system cost. ICL8001G employs quasi-resonant operation modes with integrated power factor control for off-line residential LED lighting applications in particular 40W / 60W / 100W incandescent bulb replacements.

Highly efficient LED Bulb Driver - Infineon

Infineon ICL8001G - Bulb Driver

The EVAL-LED-ICL8001G-Bulb02 demonstrates the single-stage flyback and PFC controller ICL8001G in an LED  Bulb application. Its quasiresonant operation mode, primary side control, integrated PFC and phase-cut dimming  control makes it the best in class system solution for dimmable LED bulbs.

Thursday, March 06, 2014

The Evolution of Temperature Control

A closed loop controller is the heart of an Industrial Automation System. Right from an On-Off Hysteresis Controller to a Auto Tune PID Controller, we find solutions of different complexities. Each solution might suit a particular system; depending on the requirements of Ease-of-use, Cost and Process Type.
Evolution of Temperature Control
  • Bimetal Thermostat
  • Analog Dial On-Off Controller.
  • Analog Dial Proportional Controller.
  • Digital Display - Analog Controller - On-Off.
  • Digital Display - Analog Controller - Proportional.
  • Digital Display - Analog Controller - PID.
  • Microcontroller Based Process Controller. (On-Off, Prop., Universal TC, RTD, mA Input)
  • Process Profile Controller (Microcontroller Based).
  • Microcontroller Based Fuzzy or Auto-Tune PID Controller.
  • Data Logger, Computer, PLC or SCADA based Solutions.
Even today, the controllers at every stage of evolution, from the thermostat to Auto-Tune, are used in many countries, for many different industrial applications. No solution above is obsolete! The developing Countries still use electro-mechanical or semi-automatic means for control in some areas.

The Evolution of Temperature Control
 A PC based multiplexed scanner controller with data-acquisition cards and I/O Cards can be solution for Laboratory or Research. This is used when real time control is not required or where the control failure will not lead to damage or loss.

A PLC or Microcontroller based controller should be used with a Analog Controller Protection or Over temperature Trip-Alarm.

Outputs could be Relay or SSR, Voltage and Current outputs like 0-10V and 4-20mA are needed sometimes to drive DC/AC Drives or to control Motorized Valves. Relays and SSR can be On-Off or Time proportional (PWM). The Cycle times can be 10-20 Secs for Electromagnetic Relay and around 1 Sec for SSR. This is because Mechanical Relays and contacters have limited number of operations. The zero crossing SSR has to be cycled slower than mains frequency.

In Curing rubber, which is one of the more complicated process, we need a profile based controller, which also triggers other timers or counters which need to be activated at different segments.

When a very big area is controlled, with materials or load placed un-symmetrically, Every corner or section has to have separate sensor and controller. These are then governed by a SCADA, Supervisory PLC or Master Controller.

Industrial Process Control Circuits

Even a Big Die for Plastic Moulding with an Unsymmetrical Object or long object to be moulded; needs compensation for sides which will absorb more heat.