Showing papers by "ebm-papst published in 2020"

Measurement-Based Optimization of Thermal Networks for Temperature Monitoring of Outer Rotor PM Machines

Abstract: This paper is about deriving suitable lumped parameter thermal networks for modeling the transient thermal characteristics of electric machines under variable load conditions. The network should allow for an accurate estimation of the temperatures of critical machines’ components. In best case, the model can be run in real time to adapt the motor control based on the load history and maximum permissible temperatures. Consequently, the machine’s capabilities can be exhausted at best considering a highly-utilized drive. The model further shall be as simple as possible while guaranteeing a decent accuracy of the predicted temperatures. A lumped parameter thermal network is selected and its characteristics are explained in detail. Besides the model selection and the optimization of its critical parameters through an evolutionary optimization strategy, an experimental setup will be described in detail. The model accuracy is evaluated for both static and dynamic test cycles with changing load torque and speed requirements. Finally, the significant improvement of the accuracy of the predicted motor temperatures is presented and the results are compared with measurements.

Beamforming for measurements under disturbed propagation conditions using numerically calculated Green's functions

Abstract: Beamforming methods for sound source localization are usually based on free-field Green's functions to model the sound propagation between source and microphone. This assumption is known to be incorrect for many industrial applications and the beamforming results can suffer from this inconsistency regarding both, accuracy of source power estimation, and accuracy of source localisation. The aim of this paper is to investigate whether the use of numerically calculated Green's functions can improve the results of beamforming measurements. The current test cases of numerical and experimental investigations consists of sources placed in a short rectangular duct. The measurement is performed outside the duct in a semi-anechoic chamber. A typical example for this kind of installation is a fan with a heat exchanger. The Green's functions for this test case are calculated numerically using the boundary element method. These tailored Green's functions are used to calculate the corresponding beamforming steering vectors. The weighting of the Green's functions in the steering vectors has a decisive influence on the beamforming results. A generalization of the common steering vector formulations is given based on two scalars. It is shown that arbitrary differentiable Green's functions can be used to find the correct source position or source power level by using the appropriate steering vector formulations. Beamforming measurements are performed using a loudspeaker as a reference source at different positions in the heat exchanger duct. The measurements are evaluated in the frequency domain and by means of different validation criteria it can be shown that the results with the numerical calculated Green's function are improved compared to free field beamforming especially at low frequencies.

Consideration of the Skin Effect in a Transient Model of Line-Start Synchronous Reluctance Machines

Abstract: An analytical calculation model of line-start synchronous reluctance machines with flux barriers filled with conductive material considering the skin effect is presented. The rotor bars are divided into multiple layers, where the current density is assumed to be evenly distributed. The subdivision is done with respect to the skin depth in the used material at the given frequency. The stator and rotor voltage equations are adapted to the new approach. The results of the analytical model at stall and synchronized state are compared to a transient linear two-dimensional Finite Element Analysis. As proven by the good agreement of the stator currents and rotor winding losses with FEM, the proposed method to consider the skin effect is accurate.

Electric motor, internal rotor and rotor plate

Abstract: An internal rotor (150) for an electric motor (100) has a laminated rotor core (200; 600) with a multiplicity of rotor plates (310), which laminated rotor core (200; 600) has multiple pockets (210) in each of which a rotor magnet (221; 621) is at least partially arranged. The rotor plates (310) have first recesses (211; 611) for forming the pockets (210) and at least a first rotor plate (11) which has at least a second recess (231-236; 631), which second recess (231-236; 631) is assigned to a first recess (211-216; 611), wherein a sprung web-shaped clamping element (291; 691) is formed between the second recess (231-236; 631) and the assigned first recess (211-216; 611), which clamping element (291; 691) is tensioned towards the second recess (231-236; 631) by the assigned rotor magnet (221, 621), and which clamping element (291; 691) as a result applies a force to the assigned rotor magnet (221; 621) toward the first recess (211-216; 611) in order to hold the assigned rotor magnet (221; 621) in the pocket (210). A rotor plate (311) for holding a rotor magnet (221) in a pocket (210) of a laminated rotor core (200; 600) is also presented.

Device For Reducing Harmful Bearing Voltages

Abstract: A device (1) to reduce harmful bearing voltages in an electrical machine (M) fed by a DC link voltage of a DC link. The electrical machine has a rotor (2) and a stator (3) with windings (W), and is insulated to ground. At least two bearings (4), with an outer bearing ring (4a) and an inner bearing ring (4i), are between the rotor (2) and the stator (3). A shielding arrangement (S) is between the windings (W) of the stator (2) and the respective outer bearing rings (4a). A stator electrical connecting arrangement (5) is connected to a potential that is stable with respect to the DC link.

Mixed-flow or diagonal ventilating fan with consistent cooling

Abstract: A self-cooling diagonal ventilating fan (30; 130) has a fan housing (36) and a fan wheel (80), rotatable around a rotation axis (168), that has, associated with it, an electronically commutated motor (73) which has an internal stator (64) and an external rotor (68, 152). Cooling air, after it emerges from the electric motor (73), is drawn through at least one opening (90) formed in the fan wheel (80) to the outer side of the fan wheel (80), in order, during operation, to maintain a constant cooling air stream (158) in a consistent flow direction through the internal stator (64) of the electric motor (73), regardless of possible backpressure.

Auto-addressing with position determination of bus subscribers

Abstract: The present invention relates to a position-sensing method and a position-sensing device for sensing the installation location (F1,....., Fi) of slave units (SE1,....., SEi) in an operating region (A1,....., Ai) of a system (A) comprising a number i of adjacent operating regions (A1,....,Ai) each having a slave unit (SE1,..., SEi), the individual slave units (SE1, SEi) having a changeable operating function for achieving or changing the physical state in the operating region (A1,....., Ai) in question of the system and a sensor (S1,...., Si) being provided in each operating region (A1,...., Ai) in question in order to sense a measurement variable (T) proportional to the physical state in the operating region in question and an evaluating device being provided in order to determine, upon the activation or changing of the operating function of at least one slave unit (SE1,..., SEi), the installation location (F1,..., Fi) of said slave unit from the change in the measurement variables (T) over time.

Synchronous Machine And Method For Regulating The Rotational Speed Of The Synchronous Machine Without Sensors

Abstract: A permanent magnet synchronous machine (1) having a rotor (R) and a stator (S). Connection terminals (2) apply a feed alternating voltage with a feed frequency (f0). The permanent magnet synchronous machine (1) has a motor controller (10). The controller (10) has an assembly (11) to detect the terminal voltage on the connection terminals (2) and the current frequency (fa). Also, the controller has an analysis device (12). The analysis device (12) ascertains whether the current frequency (fa) contains a frequency component (fr) with a frequency that deviates from the feed frequency (f0).

Holding system for a fan

Abstract: The invention relates to a holding system for a fan comprising a wall ring and a protective grille. A holding system according to the invention for a fan with a protective grille having at least one protective-grille strut arranged in the circumferential direction and comprising a wall ring having a first end face is characterized in that the wall ring has at least one first connecting element on the first end face and the protective grille has at least one second connecting element, whereby the first connecting element can be operatively connected to the second connecting element, and the second connecting element is arranged so as to be sunk in the first end face of the wall ring.

Diagonalventilator mit optimiertem Gehäuse

Abstract: Die Erfindung betrifft einen Diagonalventilator (1) umfassend einen Elektromotor (10), ein Gehause (11) und ein innerhalb des Gehauses (11) aufgenommenes und uber den Elektromotor (10) antreibbares Diagonallaufrad (12), dessen im Betrieb erzeugte Diagonalstromung in eine axiale Stromungsrichtung umgelenkt wird, wobei das Diagonallaufrad (12) in Umfangsrichtung verteilte Laufradschaufeln (121) sowie einen Lufteintritt und einen Luftaustritt aufweist, wobei das Gehause einen Stromungskanal fur eine durch das Diagonallaufrad erzeugte Luftstromung bildet, der einen nicht-rotationssymmetrischen Axialabschnitt und einen sich in Stromungsrichtung gesehen axial unmittelbar axial daran anschliesenden zylinderformigen Axialabschnitt aufweist, wobei ein luftaustrittsseitiges radial auseres Ende des Diagonallaufrads im zylinderformigen Axialabschnitt des Stromungskanals des Gehauses angeordnet und zwischen dem radial auseren Ende und dem Gehause ein Luftspalt vorgesehen ist, und wobei der nicht-rotationssymmetrische Axialabschnitt des Diagonallaufrads in einem sich an den Luftspalt lufteinlassseitig anschliesenden Bereich des Stromungskanals in einer Axialebene mit dem Diagonallaufrad angeordnet ist, so dass der nicht-rotationssymmetrische Axialabschnitt das Diagonallaufrad zumindest abschnittsweise umschliest.

Vorrichtung zur kontinuierlichen Schwingungsüberwachung

Abstract: Die Erfindung betrifft eine Drehfeldmaschine (1), insbesondere ein Elektromotor mit einem Stator und einem Rotor, ausgebildet mit einer Motorsteuerung (10) zum Steuern der Rotation und der Drehzahl n des Rotors der Drehfeldmaschine (1), wobei die Motorsteuerung (10) eine Schwingungssensorik (20) integral aufweist, um Ist-Messwerte von Schwingungen der Drehfeldmaschine (1) abhangig von der Drehzahl n zu erfassen.

Pump device with pump ring having curved contact portion

Abstract: A pump device for pumping a liquid, has a hydraulics housing (12), in which a pump ring (14) with a contact surface (46), a pump ring support (16) and an eccentric (18), which can be driven by a shaft (20), are accommodated. The hydraulics housing (12) has an annular portion (22) and a first and a second lateral section (24, 26), the two lateral sections (24, 26) being arranged opposite each other. The pump ring (14) is mounted between the two lateral sections (24, 26) of the hydraulics housing (12) at least in some portions. The profile of the contact surface (46) has a contour with a curvature that changes at least in portions, and specifically in such a way that the curvature increases at least in some portions towards the ends of the contact surface (46).

Valve monitoring system for a coaxial dual-safety valve

Abstract: The invention relates to a valve monitoring system for a coaxial dual-safety valve of a gas valve unit which controls the gas request of a gas burner resulting in the course of a heat request and which has at least the coaxial dual-safety valve and a control valve serially arranged downstream of the dual-safety valve in a fluidic manner in order to control the gas quantity.

Method for regulating a gas mixture by using a gas sensor and a gas mixture sensor

Abstract: A method for regulating a gas mixture formed from a gas and a fuel gas in a fuel gas-operated heating appliance, wherein the gas mixture is created by providing and mixing a gas quantity by way of a first control element and a fuel gas quantity by way of a second control element, wherein a microthermal gas sensor and a gas mixture sensor are used and sensor signals are relayed to a controller, and wherein upon change in the detected sensor signal [of the] gas sensor the newly detected sensor signal of the gas sensor is compared to reference values which have been measured in the laboratory and saved in a table of values in the controller and from this a target value of the sensor signal of the gas mixture sensor is determined without a mixture ratio of the gas mixture composed of fuel gas and gas being changed.

Stator apparatus with wiring end disc for an electric motor, and use of the stator apparatus

Abstract: The invention relates to a stator apparatus (2) for an electric motor having a plurality of windings (1' to 12') which are provided on a winding carrier (4), are designed for electromotively interacting with a rotor which is mounted such that it can rotate about a centre axis relative to the winding carrier (4), extend parallel in relation to one another and in relation to the centre axis and are arranged along a profile which is in the form of an arc of a circle and are designed such that they can be individually electrically contacted by winding connections of a winding wire, wherein at least two discs and/or annular, electrically conductively designed wiring rings (8u, 8v, 8w) are associated with the windings (1' to 12') such that they are arranged, in a manner electrically insulated from one another, along an axial direction of the centre axis on the winding carrier (4) such that the winding connections with the same electrical connection polarity (U; V; W) of the windings (1' to 12') are connected to the wiring ring (8u, 8v, 8w), which is associated with this connection polarity (U; V; W), for external common contact-connection in a non-releasable manner by means of welding hooks (20) which are integrally formed with the radially inner side of the wiring ring (8u, 8v, 8w), wherein the wiring rings (8u, 8v, 8w) are integrated into a hollow-cylindrical wiring end disc (6), and in that an annular deflection disc (10) with deflection pins (12), which are arranged distributed around the periphery of the inner side of the deflection disc (10), for deflecting the winding wire is provided on the wiring end disc (6) in the axial direction.

Method for producing a drive unit device

Abstract: The invention is based on a method for the production of a drive unit device, in particular of a fan device, which has at least one first modular unit (12) and at least one second modular unit (16) which concentrically receives at least part of the first modular unit (12), wherein the first and second modular units (12, 16) are intended to cooperate mechanically in a change in torque, wherein in at least one method step (100, 110) the first modular unit (12) is secured in the second modular unit (16). In order to increase safety and reduce method costs, it is proposed that the first modular unit (12) be secured in the second modular unit (16) by at least one concentric pressing process step.

Method for monitoring rolling bearings

Abstract: The present disclosure relates to a method and an apparatus for monitoring a rolling bearing of an electric motor, wherein the rolling bearing forms a capacitive parasitic antenna, having the following steps of: a capturing the electromagnetic spectrum emitted by the parasitic antenna in a manner triggered by spark formation in the rolling bearing over a respectively defined period t during operation of the electric motor; b evaluating the number N of electromagnetic pulses (a, b, c, d, e) received in the spectrum and the amplitude A of said pulses; c capturing the change in the number N of electromagnetic pulses (a, b, c, d, e) and/or the amplitude A of said pulses, and d determining whether the increase in the number N and/or in the amplitudes A of the electromagnetic pulses (a, b, c, d, e) increases in a non-linear manner with time

Method for checking a time-discrete signal value of a sensor for freedom from errors

Abstract: The invention relates to a method for checking a time-discrete signal value of a sensor for freedom from errors, wherein the signal value from the sensor is transformed by two different evaluating devices of an electronics system into a first measured value and a second measured value, wherein the first and the second measured values are transmitted by the electronics system to a control system and the control system calculates a first control signal from the first measured value and in parallel therewith a second control signal from the second measured value, wherein the control system comprises a comparator which compares the first control signal and the second control signal to verify the identity thereof.

Rotary pump with deformable pump ring

Abstract: The invention relates to a pump device (10) for pumping a fluid (13), comprising: a pump housing (12) having an annular portion (22); a pump ring (14), which is deformable and defines an annular pump chamber (57) at least in some portions; a first connection (51) and a second connection (52), said first connection (51) and said second connection (52) being in fluid communication with the pump chamber (57); an eccentric (18), which is designed to be rotatable relative to the pump housing (12) and which is arranged such in the pump device (10) that the eccentric (18), depending on a current rotational position of the eccentric (18), deforms the pump ring (14) in such a way that the pump ring (14) presses at least partially against the annular portion (22) in order to pump, by way of a rotation of the eccentric (18), the fluid (13) along the pump chamber (57) from the first connection (51) to the second connection (52) depending on the current rotational position of the eccentric; and a clamping element (114), which is designed to statically press the pump ring (14) against the annular portion (22) of the pump housing (12) in a clamping link region (45). The pump ring (14) has at least one recess (47) for accommodating at least part of the clamping element (114), said recess (47) being dimensioned such that in each rotational position of the eccentric (18) at least in some portions a distance (48) between the radially inner side (50) of the clamping element (114) and the pump ring (14) is provided.

Diagonalventilator mit Nachleiteinrichtung

Abstract: Die Erfindung betrifft einen Diagonalventilator umfassend einen Elektromotor, ein Gehause und ein innerhalb des Gehauses aufgenommenes und uber den Elektromotor antreibbares Diagonallaufrad, dessen im Betrieb erzeugte Diagonalstromung von einer Innenwand des Gehause in eine axiale Stromungsrichtung umgelenkt wird, wobei in axialer Stromungsrichtung gesehen dem Diagonallaufrad anschliesend eine Nachleiteinrichtung mit einer Vielzahl von in Umfangsrichtung verteilten Leitschaufeln angeordnet ist, welche eine von dem Diagonallaufrad erzeugte Luftstromung vergleichmasigt, wobei die Leitschaufeln eine Radialerstreckung von einem Nabenbereich der Nachleiteinrichtung zu dem Gehause aufweisen, und wobei eine gedachte Verlangerung im Abstromwinkel des Diagonallaufrads in einem axialen Abstand K von dem Diagonallaufrad auf die Innenwand des Gehauses trifft und die Nachleiteinrichtung in einem axialen Abstand H zu dem Diagonallaufrad angeordnet ist, dass gilt 0,75≤K/H≤1,25

Verfahren zur Erkennung eines fehlerhaften Betriebs eines über einen Gleichstrommotor angetriebenen Gasgebläses

Abstract: Die Erfindung betrifft ein Verfahren zur Erkennung eines fehlerhaften Betriebs eines uber einen elektronisch kommutierten Gleichstrommotor angetriebenen Gasgeblases, wobei der Gleichstrommotor des Gasgeblases uber eine integrale Motorelektronik geregelt wird, wobei uber die Motorelektronik eine im Betrieb benotigte elektrische Stromaufnahme des Gleichstrommotors zur Erreichung einer vorbestimmten Geblasedrehzahl des Gasgeblases als Messgrose gemessen wird, wobei eine Plausibilitatskontrolle der gemessenen elektrischen Stromaufnahme durch die Motorelektronik erfolgt, bei welcher der gemessene Wert der elektrischen Stromaufnahme bei der vorbestimmten Geblasedrehzahl mit einer in der Motorelektronik hinterlegten Referenzwertkennlinie der Stromaufnahme verglichen wird und bei Abweichungen des gemessenen Werts der elektrischen Stromaufnahme auserhalb eines Toleranzkorridors um die Referenzkennlinie von der Motorelektronik eine Warnung und/oder ein Fehlercode ausgegeben wird.

Multi-motor operation

Abstract: The invention relates to a method for the closed-loop and open-loop control of two or more EC motors operated using a common converter, wherein for the purpose of setting the operating point of the EC motors, common open-loop or closed-loop control using at least one controller is provided, wherein a combination of at least two control options is provided and in this case a controlled variable regulates the voltage setting at the output of the converter such that the two or more EC motors follow an intended sequence of operating points in a stable manner.

Modular aufgebautes Radantriebsmodul

Abstract: Die Erfindung betrifft ein Radantriebsmodul umfassend ein Rad (R), ein Uberlagerungsgetriebe (G) sowie einen ersten Elektromotor (M1) und einen zweiten Elektromotor (M2), wobei der erste und der zweite Elektromotor (M1, M2) ausgebildet sind, das Rad (R) gemeinsam mittels des Uberlagerungsgetriebes (G) um eine Radachse (A) anzutreiben und um eine zu der Radachse (A) orthogonale Lenkachse (L) zu lenken, das Radantriebsmodul ferner eine erste Motorelektronik (10) zur Ansteuerung des ersten Elektromotors (M1) und eine zweite Motorelektronik (20) zur Ansteuerung des zweiten Elektromotors (M2) sowie eine Zentralelektronik (30) umfasst, die mit der ersten und zweiten Motorelektronik (10, 20) einen Signalaustausch ermoglichend verbunden ist, und wobei das Radantriebsmodul eine Steuerungslogik zur Steuerung des ersten und zweiten Elektromotors (M1, M2) umfasst, welche durch die erste und zweite Motorelektronik (10, 20), die Zentralelektronik (30), eine Applikationselektronik (40), welche einen Signalaustausch ermoglichend mit der Zentralelektronik (30) verbunden ist, oder gemeinsam durch die Zentralelektronik (30) und die erste und zweite Motorelektronik (10, 20) bereitgestellt ist.

Pump device with deformable pump ring

Abstract: The invention relates to a pump device for pumping a liquid having a hydraulics housing (12), in which a pump ring (14), a pump ring support (16), and an eccentric (18) are accommodated, which eccentric is to be driven by a shaft (20), which defines an axial and a radial direction, wherein the pump ring (14) has a first axial side (45) and a second axial side (47), wherein the hydraulics housing (12) comprises an annular portion (22) and a first and a second lateral section (24, 26), wherein the two lateral sections (24, 26) are arranged opposite each other, wherein the pump ring (14) is arranged, at least in some portions, between the two lateral sections (24, 26) of the hydraulics housing (12), and wherein on the first axial side (45) and the second axial side (47), the profile of the pump ring (14) in each case follows a contour with an S-formed curve (32) with a convex section (34) and a concave section (36), wherein the convex section (34) lies further outwards in a radial direction of the shaft (20) in comparison with the concave section (36).

Apparatus For Reducing Dangerous Bearing Voltages

Abstract: The present invention relates to an apparatus (1) for reducing dangerous bearing voltages in an electric machine (M) having a rotor (2) and having a stator (3), wherein, between the rotor (2) and stator (3), a rotor-side and stator-side bearing outer ring (4r, 4s) and a respective bearing inner ring (4i) are provided, comprising a connection electronics system for connection of the motor (M), wherein a compensation arrangement (20) is provided to adjust the potential (ULA-stator) of the bearing voltage at the bearing outer rings (4r, 4s) and the respectively corresponding bearing inner ring (4i) to an identical value, wherein the compensation arrangement (20) comprises an impedance (ZKOMP), consisting of at least one first impedance (ZKOMP,R) between the stator (3) and the rotor-side bearing outer ring (4r) and wherein the impedance (ZKOMP) has at least one impedance (ZKOMP.S) between the stator (3) and the stator-side bearing outer ring (4s).

Positioning system and method for determining the position of fans

Abstract: The disclosure relates to a method for determining the positions of a number of fans (Vn,m) for generating an air flow in a preferably enclosed space, which have a speed sensor for determining their position, wherein the fans (Vn,m) are arranged in rows (R1, R2, . . . , Rn) and columns (S1, S2, . . . , Sm), wherein at least the position (i, j) of one fan (Vi,j) is known.

Stator arrangement comprising a winding arrangement

Abstract: An external stator arrangement has a stator core, a wire guiding arrangement and a winding arrangement with a winding wire. The winding arrangement is designed as a delta circuit and has a number SC of stator coils. SC=N*3 where N=1, 2, 3, 4, 5, . . . . The stator core has a magnetic return path, stator poles and slots. The wire guiding arrangement has a first contact-making arrangement, a second contact-making arrangement and a third contact-making arrangement. The winding wire runs from the first contact-making arrangement, via at least one of the stator coils, to the second contact-making arrangement, from the second contact-making arrangement, via at least one of the stator coils, to the third contact-making arrangement, and from the third contact-making arrangement, via at least one of the stator coils to the first contact making arrangement. Contact elements are electrically connected to the winding wire in order to serve as winding connections.

Blower arrangement with flow dividing nozzle

Abstract: A blower arrangement comprising an impeller, which has an axial intake opening formed by a cover plate covering impeller blades at least in sections, by an intake nozzle connected upstream of the impeller, which extends at least in sections into an overlap section in the intake opening of the impeller, wherein a circumferential nozzle gap is formed between the intake nozzle and the cover plate of the impeller, an outer nozzle, which is arranged spaced apart in the radial direction in relation to the impeller and the intake nozzle and enclosing them in the circumferential direction. A first circumferential radial gap is provided between the outer nozzle and the intake nozzle, which forms an inlet nozzle duct extending in the flow direction. A second circumferential radial gap is provided between the outer nozzle and the cover plate of the impeller, which forms a gap duct extending in the flow direction.