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TYPES OF LOAD. TYPES OF LOAD. CONSTANT TORQUE LOAD :. TORQUE. 100. 80. NOTE :- A CONSTANT TORQUE LOAD IS NOT NECESSARILY 100% LOAD . PERCENT TORQUE AND HORSEPOWER. 50. 100. 50. PERCENT SPEED. TYPES OF LOAD. CONSTANT TORQUE LOAD :.
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TYPES OF LOAD CONSTANT TORQUE LOAD : TORQUE 100 80 NOTE:- A CONSTANT TORQUE LOAD IS NOT NECESSARILY 100% LOAD PERCENT TORQUE AND HORSEPOWER 50 100 50 PERCENT SPEED
TYPES OF LOAD CONSTANT TORQUE LOAD : Positive Displacement Pumps Conveyors Compressors Root Blowers
TYPES OF LOAD VARIABLE TORQUE LOAD : 100 80 TORQUE 60 TORQUE & POWER IN % 40 POWER 20 0 10 20 30 40 50 60 70 80 90 100 SPEED IN %
TYPES OF LOAD VARIABLE TORQUE LOAD ( Torque Varies as Square of Speed) Centrifugal Pumps Centrifugal Fans
TYPES OF LOAD CONSTANT HORSEPOWER LOAD : TORQUE 100 HORSE POWER TORQUE PERCENT TORQUE AND HORSEPOWER 50 100 50 150 200 PERCENT SPEED
TYPES OF LOAD CONSTANT HORSEPOWER LOAD : • Lathe • Grinders • Winders • Coilers
Energy Savings Key Applications Areas – The Energy Guzzlers • Fans • AHU • Ventilation / Fresh Air • Exhaust • Cooling Tower Fans • ID / FD Fans • Pumps • Process Water • Pressure booster pumps • Compressors • Reciprocating, Screw, Centrifugal
FAN APPLICATION Air flow control of fan Outlet side damper Inlet side damper
Comparison of motor power for fan drive system 100 Damper control Energy saving Shaft or power consumption Inverter control Shaft power for speed control 0 100 50 Airflow or motor speed (%)
Flow Control-Affinity Laws • Flow Speed • Pressure / Head Speed 2 • Power Speed 3 Benefits of Flow Control…
Fundamentals- Traditional Throttle Flow control is achieved by riding the pump or the fan curve…
Fundamentals- Evolution Flow control is achieved by riding the System Curve…
PRINCIPLE - ENERGY SAVING BY SPEED CONTROL OF PUMPS ENERGY SAVING = SHADED REGION = AREA (OEAD) - AREA (OFCD) A E THROTTLECONTROL B PRESSURE F C SPEEDCONTROL O D VOLUME
The energy saving effect to the pump type Axial pump 2.0 mixed flow pump Head H (P.U.) System resistance Centrifugal pump 1.0 Energy-saving effect As shown in the figure, the sharper the pump characteristic is i.e., the bigger the comparative speed is, the bigger the 1st energy saving effect becomes. 0 1.0 0.5 Flow rate Q (P.U.)
PRINCIPLE - ENERGY SAVING BY SPEED CONTROL As Per Affinity Laws Flow (%) HP (%) Required 100 100 75 42 50 12.5
Compressors • Operates in a load/ unload cycle. Load 100% Time
110PSI 100PSI 20 PSI 90PSI PRESSURE MINIMUM SYSTEM PRESSURE REQUIRED TIME 100% FULL LOAD POWER DURING LOAD CYCLE 20-30% OF FULL LOAD POWER DURING UNLOAD CYCLE POWER TIME UNLOAD LOAD Compressor–Load/Unload Control Conventional compressor system work between two set pressures, resulting in pressure generated being higher than the pressure required in the system.
Disadvantages of Traditional Compressor: • Energy consumption as high as 20-30% of full load power during unload period. • Pressure in the system is much more than the minimum system pressure required, resulting in extra power consumption and wear and tear of the mechanical system. • 20PSI extra pressure in the system, results in 10% extra power consumption. • DOL or star/delta starting sequence on a motor creates a power surge in electrical system.
A I R R E C E I V E R PRESSURE TRANSMITTER AC MOTOR AIR COMPRESSOR To Plant VARIABLE SPEED AC DRIVE 4-20 mA/ 0-10V PRESSURE FEEDBACK SIGNAL 3 Ph./ 415V Supply Typical Schematic
Advantages with Inverter Control: • Variablepressure setting possible. • Accurate pressure control. • No unload cycle, thus reducing power consumption typically by 20 to 30% of full load power. • Soft start with inverter control, power to the motor is increased progressively, avoiding peak power demand in the electrical system.