01-08-2010, 03:29 PM
ENSAVE-Electronic Energy Saver.ppt (Size: 238.5 KB / Downloads: 151)
INTRODUCTION
Ascent Power Systems Pvt. Ltd. is the manufacturer of energy conservation systems (ENSAVE) for usages in domestic, commercial and small industrial set ups.
ENSAVE basically works for single phase lighting loads and works as a energy saver cum protector.
This is fully equipped with embedded software chips, which results greater accuracy in power-factor monitoring, high/low voltage cut-offs etc.
This device saves energy thus saving electricity bills from 15% to 25% as per the application load.
WORKING PRINCIPLE OF ENSAVE
ENSAVE basically works on the principle of On line monitoring and controlling of power factor of load.
ENSAVE uses the embedded software for monitoring and controlling of power factor.
% SAVING CALCULATIONS
Energy meters are driven on the following formula :
KWH = V.I. COS Ø T/1000
where
V = Coming supply voltage
I = Load current
T = Period
cosØ = Power factor
KWH means kilo watt-hour
This % saving increases as PF increases towards unity depending on the nature of load applied on ENSAVE.
ADVANTAGES OF ENSAVE
By reducing the Transmission and Distribution losses.
By stabilizing the demand and supply ratio.
By reducing the total load on each MSEB transformer and thereby reducing the damage percentage of transformers.
By educating the people about energy crisis and optimum utilization of energy.
ENERGY SAVING IN INDUCTION MOTOR
Originally proposed and developed by Frank Nola of NASA in the mid to late 70s.
Difficulties were experienced in the early days in applying this technology to three phase motors.
The concept of energy saving has always been an attention grabber.
Unfortunately, the marketing was based on the results achieved with very small machines.
LOSSES OF INDUCTION MOTOR
There are 5 losses of IM :
Iron Loss
Copper Loss
Frictional Loss
Windage Loss
Sound Loss
Frictional Loss, Windage Loss and Sound Loss are independent of shaft load.
Iron Loss is Constant -> Independent of shaft load
Copper Loss is dependent of shaft load.
CHARACTERISTICS OF INDUCTION MOTOR
The current flowing into an induction motor comprises of:
Magnetizing current.
loss current and
load current.
MEASUREMENT TECHNIQUES
The standard methods of measuring the input power
on a three phase three wire circuit, are either to use
The single phase watt meters,
one per phase and sum the results, or
use the two watt meter method, or a three phase watt meter.
Measurements made on one phase,
and multiplied by three can be extremely erroneous,
especially under light load conditions.
PAY BACK PERIODS
In many situations, the energy saved would be increased
by altering the operation of the machine to spend less time idling.
To calculate the payback period, it is essential to have an
accurate measurement of the actual energy (kW) being saved.
When the energy saved is known and verified,
then this can be multiplied by the cost of the energy per kilowatt
hour to give a cost saving per hour.
Dividing the savings per kilowatt hour into the installed cost of the energy saver, will give the required number of operating hours to give a payback.
CONCLUSION
¢ The basic concept of reducing the voltage on induction motors operating at less than full load, and thereby reducing the energy consumed, works provided that several constraints are applied.
¢ The motor efficiency can only be improved when it has dropped considerably below the maximum efficiency for that motor.
¢ As the maximum energy that can be saved is a portion of the iron loss, the best savings are going to be on motors with a very high iron loss. Typically, these will be small motors, operating above their design voltage, or below their design frequency.