Sensorless Brushless DC-Servomotors

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Ellen Douglas
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Sensorless Brushless DC-Servomotors FAULHABER Brushless DC-Servomotors are built

They are precise, have exceptionally long lifetimes and are highly reliable.

that these motors deliver top performance dynamics within minimum overall

The SMARTSHELL motor series is especially designed for use in sensorless motor

1 Sensorless Brushless DC-Servomotors FAULHABER Brushless DC-Servomotors are built for extreme operating conditions. They are precise, have exceptionally long lifetimes and are highly reliable. Outstanding qualities such as smooth running and especially low noise levels are of particular note. The rare earth magnet as rotor, and the FAULHABER skew winding technology, ensure that these motors deliver top performance dynamics within minimum overall dimensions. The SMARTSHELL motor series is especially designed for use in sensorless motor applications and complements the existing Brushless DC-Servomotor product line. The modular design concept offers Hall sensor modules, for precise speed and positioning control, as well as a selection of precision spur and planetary gearheads to increase the torque range. 9

Sensorless Brushless DC-Servomotors Technical Information Three phase sensorless brushless DC-Servomotor Sensorless Brushless DC-Servomotor Rear bearing cover Ball bearing Shaft Permanent magnet Lead

Front bearing cover 7 Concept Technology The SMARTSHELL motor series is designed with high quality components, as used in the high-performance brushless DC-Servomotors, in an innovative and simple

Performance Lifetime The performance lifetime of the sensorless SMARTSHELL brushless motors is mainly influenced by the ball bearings service life.

2 Sensorless Brushless DC-Servomotors Technical Information Three phase sensorless brushless DC-Servomotor Sensorless Brushless DC-Servomotor Rear bearing cover Ball bearing Shaft Permanent magnet Lead wires Spring washer 7 Encapsulated all-inone stator with: 7. Printed circuit 7. Coil 7. Lamination stack 7. Front bearing cover 7 Concept Technology The SMARTSHELL motor series is designed with high quality components, as used in the high-performance brushless DC-Servomotors, in an innovative and simple design solution. The combination of leading-edge technology, know-how and long standing experience gives the sensorless SMARTSHELL brushless motors cost effective performance and reliability. Performance Lifetime The performance lifetime of the sensorless SMARTSHELL brushless motors is mainly influenced by the ball bearings service life. On average, the lifetime may exceed hours if the motors are operated within the recommended values indicated on the data sheet SMARTSHELL - an innovative shell with a High-Tech core. The SMARTSHELL brand name synthesizes the design concept of this new motor series. The skew-wound self-supporting coil, System FAULHABER, the printed circuit board, the laminated stack and the front-end bearing cover are all encapsulated and meshed together with a mould-injected LCP (Liquid Crystal Polymer), exhibiting outstanding mechanical and thermal features. With this approach, a monolithic (all-inone), particularly stable, compact and robust stator is obtained. The anodized aluminium front and rear bearing covers optimally secure the fit of the preloaded ball bearings, ensure heat dissipation and allow secure motor mounting in the application. A dynamically balanced rotor with a powerful two-pole NdFeB magnet completes the motor construction. 9

Hall sensor Module Hall sensor Module Support Printed circuit Hall

design concept of the SMARTSHELL motors offers two Hall sensor

With these modules assembled to the rear end of the motors, the BDS

options are available for use with the appropriate drive electronics.

with servoamplifiers are the ideal solution for all applications

80 Index Example E 0 BSL 807 Motor Length Motor Diameter Available

Shaft Ø mm U = Shaft Ø mm Production date code (ww.

3 Hall sensor Module Hall sensor Module Support Printed circuit Hall sensors Wires Magnetic disc Cover Concept - Technology The modular design concept of the SMARTSHELL motors offers two Hall sensor modules for precise speed and position control. With these modules assembled to the rear end of the motors, the BDS (Brushless Digital Sensors) and BAS (Brushless Analog Sensors) options are available for use with the appropriate drive electronics. Ordering information Drive Electronics SMARTSHELL motors together with servoamplifiers are the ideal solution for all applications requiring long performance lifetime, such as fans, pumps, stirrers and scanners. Example Scale : BAS 707 MINIMOTOR SA swiss made 807 SMARTSHELL E0BSL 80 Index Example E 0 BSL 807 Motor Length Motor Diameter Available versions: Nominal Voltage Output shaft: E = Pinion m = 0,; z = 9 S = Shaft Ø mm U = Shaft Ø mm Production date code (ww.yy) - not necessary for ordering BSL = Brushless Sensorless Standard BAS = Brushless Analog Sensors Optional BDS = Brushless Digital Sensors Hall Sensor Module Brushless DC-Servomotor 9

4 Sensorless Brushless DC-Servomotors Technical Information Notes on technical data All values at C. All values at nominal voltage, motor only, without load. All parameters calculated at thermal limit are given with a Rth value reduced by %.. Nominal voltage UN [Volt] The direct voltage applied on the motor phases correspond to a bipolar supply with a 0 square-wave commutation logic. Definition of motor parameters η, no and Io are directly related to it. A higher or lower voltage may be applied according to the application requirement.. Terminal resistance, phase to phase R [ ] ±% The resistance measured between two motor phases. The value is directly affected by the coil temperature (temperature coefficient: α = 0,00 K - ).. Output power P max. [W] The maximum obtainable mechanical power achieved by the motor at continuous operation and at the thermal limit. This power can only be obtained at high speeds. P max. = π n (k m I e max. C o C v n) Efficiency ηmax. [%] The max. ratio between the absorbed electrical power and the obtained mechanical power of the motor. It does not always correspond to the optimum working point of the motor.. No-load speed no [rpm] ±% The maximum speed the motor attains under no-load conditions at the nominal voltage. This value varies according to the voltage applied to the motor. n o = (U n I o R) 000 k E. No-load current lo [A] ±0% The current consumption of the motor at nominal voltage and under no-load conditions. This value varies proportionally to speed and is influenced by temperature. I o = C o + C v n o k M 7. Stall torque MH [mnm] The torque developed by the motor at zero speed and nominal voltage. M H = k M U N C o R 9. Viscous damping factor CV [ 0 - mnm/rpm] The multiplier factor defining the torque losses proportional to speed. This torque is due to the viscous friction of the ball bearings as well as to the Foucault currents in the stator, originated by the rotating magnetic field of the magnet. 0. Speed constant kn [rpm/v] The speed variation per Volt applied to the motor phases at constant load. k n = n o = 000 U N I o R. Back-EMF constant ke [mv/rpm] the induced voltage in the motor phases and the rotation speed. k E = π k M 0. Torque constant km [mnm/a] the torque developed and the current drawn.. Current constant ki [A/mNm] the current drawn and torque developed. k I = k M. Slope of n-m curve n/ M [rpm/mnm] The ratio of the speed to torque variations. The smaller this value, the more powerful the motor. k E Δn = R ΔM π k M. Terminal inductance, phase to phase L [µh] The inductance measured between two phases at khz.. Mechanical time constant τ m [ms] The time required by the motor to reach a speed of % of its final no-load speed, from standstill. m = 00 R J k M 7. Rotor inertia J [gcm ] Rotor s mass. dynamic inertia moment. 8. Friction torque CO [mnm] The sum of torque losses not depending from speed. This torque is caused by static mechanical friction of the ball bearings and magnetic hysteresis of the stator. 9

5 8. Angular acceleration α max. [ 0 rad/s ] No-load rotor acceleration, from standstill and at nominal voltage. max. = (U N/R) k M C o 0 J 9. Thermal resistance Rth / Rth [K/W] Rth corresponds to the value between the coil and housing. Rth corresponds to the value between the housing and the ambient air. Rth can be reduced by enabling exchange of heat between the motor and the ambient air (for example using a heat sink or forced air cooling). All parameters calculated at thermal limit are given with a Rth value reduced by %. 0. Thermal time constant τ w / τ w [s] The thermal time constant specifies the time needed for the rotor and housing to reach a temperature equal to % of final value.. Operating temperature range [ C] The min. and max. permissible operating temperature of the motor.. Shaft bearings The standard bearings used for the Brushless DC-Servomotor.. Shaft load max. [N] The max. load values allow a motor lifetime of hours. This is in accordance with the values given by the bearing manufacturer. The radial load is defined for a force applied at the center of the standard shaft length. Recommended values The maximum recommended values for continuous operation to obtain optimum life performance are listed below. These values are independent each other. The recommended torque (Me max.) and current (Ie max.) are given with the Rth value reduced by %. 8. Speed ne max. [rpm] The max. operation speed limited by Foucault currents is generated by the rotation of the magnet and the magnetic field in the stator. The values are calculated at / of the max. permissible motor temperature, rounded off. n e max. = C o (T 8 T ) C o C v π 0, R th C v C v 9. Torque Me max. [mnm] The calculated torque for a motor at the thermal limit. M e max. = k M l e max. C o C v n 0. Current le max. [A] The calculated current for a motor at the thermal limit. T T π n 0, R th (C o + C v n) I e max. = R ( + (T T )) (R th + 0, R th ). Shaft play [mm] The shaft play on the bearings, measured at the bearing exit.. Housing material The housing material and the surface protection.. Weight [g] The average weight of the basic motor type. 7. Direction of rotation The direction of rotation is given by the external servo amplifier. All motors are designed for clockwise (CW) and counterclockwise (CCW) operation; the direction of rotation is reversible. 97

4,5 / 27 2,0 / steel, black coated. clockwise, viewed from the front face. ø15,9 ø17-0,052 ø6-0,05. ø3,5 8,1 ±0,3 2, T

4,5 / 27 2,0 / steel, black coated. clockwise, viewed from the front face. ø15,9 ø17-0,052 ø6-0,05. ø3,5 8,1 ±0,3 2, T DC-Micromotors Precious Metal Commutation mnm For combination with (overview on page 4-5) Gearheads: 5, 6, 6/7 Encoders: IE 6... 5 Series 3 4 77... SR Nominal voltage Terminal resistance Output power Efficiency