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Motor Actuators Basics

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Motor Actuators Basics Motor Actuators Basics - 1 - Note: All specifications and other information are not guaranteed and are subject to change without notice. Prior to any new usage of JE motor actuators it is recommended to contact Johnson Electric. All information below and content of links are subject to the disclaimer of the Johnson Electric website - 2 - Contents Overview ....................................................................................................................................................................... 4 Classification ............................................................................................................................................................. 5 DC Motors ................................................................................................................................................................. 6 Universal Motors ....................................................................................................................................................... 7 BLDC Motors ............................................................................................................................................................. 8 Synchronous Motors ................................................................................................................................................. 9 Stepper Motors ........................................................................................................................................................ 10 Shaded Pole Motors ................................................................................................................................................ 11 Solenoids ................................................................................................................................................................. 12 Piezo Motors ........................................................................................................................................................... 13 DC Motors ................................................................................................................................................................... 14 Basics ...................................................................................................................................................................... 15 Encoders.............................................................................................................................................................. 24 BLDC Motors ............................................................................................................................................................. 25 Basics ...................................................................................................................................................................... 26 Closed Loop Speed Control ................................................................................................................................ 31 Stepper Motors ........................................................................................................................................................... 32 Basics ...................................................................................................................................................................... 33 Gearmotors ................................................................................................................................................................. 46 Basics ...................................................................................................................................................................... 47 Motor mounting .................................................................................................................................................... 53 Linear motors .............................................................................................................................................................. 54 Basics ...................................................................................................................................................................... 55 - 3 - Overview - 4 - Classification DC AC 1~ Voltage Supply Voltage supply Brushed DC Motors Universal Motors Solenoids Synchronous Motors Brushless Shaded Pole Motors Brushless BLDC Motors Driver electronics Stepper Motors required Claw Pole Motors Hybrid Motors Piezo Motors JE product range - 5 - DC Motors  Contents Power supply DC Battery supply possible Driver electronics need No Effected by load torque Speed accuracy Low Manufacture tol +-10% of no load speed Open loop or closed loop speed control Speed control ↕ Voltage Closed loop – high accuracy, but sensor need Closed loop position control and sensor need Position control High effort High start torque or peak load torque Overloadablity / load inertia High Able to accelerate high load inertia 300…2000 h (limited by wear of brushes) Lifetime Low Depend on speed, current and brush config. Speed range [rpm] 1000…25000 No load speed Efficiency 60…80% At operating point of max.efficiency Power vs. size High If overload (mechan.blocking) not excluded - Winding thermal protection Need Current limitation or thermal contacts Load sensing Easy Current rises with load Stalling permissible No No or only short time (winding overheat) Electromag.interference EMI Critical Suppression means (capacitors / varistors) Detent torque Braking/Holding torque Low Braking improveable by winding short circuit Max.output power from JE [W] Linear motors from JE No JE Brand - 6 - Universal Motors  Contents Power supply AC or DC Mainly AC , direct connection to mains Driver electronics need No Effected by load torque Speed accuracy Low Manufacture tol +-10% of no load speed Open loop speed control Speed control ↕ Voltage Closed loop position control and sensor need Position control High effort Very high start torque or peak load torque Overloadablity / load inertia High Able to accelerate high load inertia 300…2000 h (limited by wear of brushes) Lifetime Low Depends on speed, current and brush config. Speed range [rpm] 10000…50000 No load speed Efficiency 60…80% Operating point of max.efficiency Power / motor size High If overload (mechan.blocking) not excluded - Winding thermal protection Need Current limitation or thermal contacts Load sensing Easy Current rises with load Stalling permissible No No or only short time (winding overheat) Electromag.interference EMI Critical Suppression means (capacitors / varistors) No permanent magnets (field winding instead) Braking (Holding) torque Low Braking improvable by winding short circuit Max.output power from JE [W] Linear motors from JE No JE Brand - 7 - BLDC Motors  Contents Power supply DC Battery supply possible Driver electronics need Yes External or inside motor Effected by load torque Speed accuracy Low Manufacture tol +-10% of no load speed Driver output voltage controlled by PWM Speed control ↕ Voltage Closed loop – using integrated Hall sensors Closed loop position control and sensor need Position control High effort Possibly Hall sensors applicable High start torque or peak load torque Overloadablity / load inertia High Able to accelerate high load inertia Only limited by bearings Lifetime High Depends on lateral force and speed Speed range [rpm] 1000…25000 For no load speed Efficiency 60…80% At operating point of max.efficiency Power vs. size High If overload (mechan.blocking) not excluded - Winding thermal protection Need Current limitation in Driver circuitry Load sensing Easy Current rises with load Stalling permissible No No or only short time (winding overheat) Electromag.interference EMI Not critical No brushes ; PWM voltage may cause EMI Detent torque Braking/Holding torque Low Braking improvable by winding short circuit Max.output power from JE [W] 80 Approximately, for continuous duty cycle Linear motors from JE No JE Brand - 8 - Synchronous Motors  Contents Power supply AC Driver electronics need No Not effected by load torque Speed accuracy High No closed loop speed control need Not possible Speed control No Speed fixed by mains supply frequency Not possible Position control No Only by limit switches Only little reserve for peak load torque Overloadablity / load inertia Low Can’t accelerate high inertia Limited by bearings Lifetime High Depends on lateral force Speed range [rpm] 250…3600 Depend on pole number and mains frequency Efficiency 15…45% Power vs. size Low Higher for 2pole motor Inductance protected Winding thermal protection No need (if winding designed for 100% duty cycle) Load sensing Difficult Load has little impact on current Stalling permissible Yes If winding designed for continuous duty cycle Electromagn.interference EMI Not critical No brushes Braking/Holding torque Low Detent torque (when power switched off) Max.output power from JE [W] 14 Approximately, for short time duty cycle S2 Linear motors from JE Yes JE brand - 9 - Stepper Motors  Contents Power supply DC Battery supply possible Driver electronics need Yes Constant voltage or Chopper driver circuitry Not effected by load torque Speed accuracy High No closed loop speed control need No additional electronics need Speed control Step frequency ↕ No sensor need Commanded by number of steps Position control Low effort No sensor need Only little reserve for peak load torque Overloadablity / load inertia
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