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    Introduction of AC DriveIntroduction of AC DriveWelcomeWelcomeLubiLubi ElectronicsToPresented By:Application DepartmentLubi Electronics

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    DC MotorDC MotorDC MotorAdvantages:Advantages:--1.1.To control the motorTo control the motor’’s s armature voltage high and armature voltage high and low for get different low for get different frequency output.frequency output.2.2.The Output Torque is The Output Torque is proportion to the A...

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    Induction Motor principleInduction Motor principle33--phase voltage phase voltage ►►Stator rotated currentStator rotated currentStator rotated current Stator rotated current ►►Stator rotated magnetic flux Stator rotated magnetic flux Stator rotated magnetic flux Stator rotated magnetic fl...

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    Motor TorqueMotor TorqueStator magnetic field rotated and drive Rotor magnetic field whiStator magnetic field rotated and drive Rotor magnetic field which ch just like 2 magnet are pursued each other just like 2 magnet are pursued each other SNNSBsBr

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    2,4,6 pole motor stator magnetic field2,4,6 pole motor stator magnetic fieldR.P.M.= Frequency*120/PoleRPM=fre*30SNSNRPM=Fre*60SNRPM=fre*20NSNSSN

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    What is AC MOTOR Drive ?What is AC MOTOR Drive ?Input a AC1Input a AC1ψψ or 3or 3ψψpower source, convert it to become DC Source power source, convert it to become DC Source (via Converter). After, using the Inverter part to become a (via Converter). After, using the Inverter part to become ...

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    Why do we need InverterWhy do we need InverterMotor: Transforms electricity into mechanical energyMotor: Transforms electricity into mechanical energyMotor application: NC machine, manufacture line, Lift, Elevator Motor application: NC machine, manufacture line, Lift, Elevator door, Textile indus...

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    AC Motor Drives FeatureAC Motor Drives FeatureFeaturesFeaturesControlling variables are Voltage & FrequencyControlling variables are Voltage & FrequencySimulation of variable AC sine wave usingSimulation of variable AC sine wave usingmodulatormodulatorFlux provided with constant Flux prov...

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    Significantly, this method does not use a feedback deviceSignificantly, this method does not use a feedback devicewhich takes speed or position measurements from the which takes speed or position measurements from the motormotor’’ shaft & feeds these back into the control loop.shaft &...

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    Currently AvailableCurrently AvailableV/HzV/HzOpen Loop Vector or Open Loop Vector or SensorlessSensorless VectorVectorClosed Loop Vector or Flux VectorClosed Loop Vector or Flux VectorNoteNote: All the above utilize : All the above utilize IGBTIGBT’’ss (For Power) & PWM switching (For Po...

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    V/HzV/HzGenerically called Generically called vvvfvvvf or Variable Voltage Variable Frequency or Variable Voltage Variable Frequency control modecontrol modeAttempts to improve low speed torque performance by means of Attempts to improve low speed torque performance by means of Fixed Voltage Boos...

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    Any improvements?Any improvements?Open Loop Vector mode....Open Loop Vector mode....Using the advantages of microUsing the advantages of micro--processors, this improves upon the processors, this improves upon the v/fv/f mode by :mode by :Mathematical Mathematical modellingmodelling of motor for ...

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    Open Loop VectorOpen Loop VectorBoost at low speeds is machine Boost at low speeds is machine -- specificspecificDefinite improvement on the N Definite improvement on the N v/sv/s T characteristics....T characteristics.........But still an approximation!!.....But still an approximation!!Finally t...

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    So whatSo what’’s next??s next??Closed Loop Flux Vector Closed Loop Flux Vector -- The exact wayThe exact wayUses a measurement device physically attached to the motor NDE, Uses a measurement device physically attached to the motor NDE, typically an encoder with Marker pulsetypically an encod...

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    Flux Vector???Flux Vector???FluxFlux : Idea is to calculate Stator Field distribution by means of : Idea is to calculate Stator Field distribution by means of measuring rotor orientation measuring rotor orientation at all instantsat all instants!!!!VectorVector : Since both direction & magnit...

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    The Net GainThe Net GainGives you the luxury of full torque right down to zero speed Gives you the luxury of full torque right down to zero speed (Hold/Standstill / Stall Tension events)(Hold/Standstill / Stall Tension events)

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    The Vital differenceThe Vital differencev/fv/f & OL Vector confer control advantages due to low speed torque & OL Vector confer control advantages due to low speed torque correction thru APPROXIMATION ONLYcorrection thru APPROXIMATION ONLYFlux Vector mode gets you an instantaneous current...

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