Diehl Ako Stiftung & Co. Kg

Dielh Ako Stiftung & Co. Kg

Martin Weinmann

Bernd Last

Stefan Zeh

Alexander Müller

Nicola-Valeriu Olarescu

Sebastian Tinius

Andreas Schmid

Roman-Hartmut Wauer

Roland Morent

Rainer Frisch

Thomas Mehrer

Radu Liviu Florea

Martin Rieser

Valeriu Olarescu

Hartmut Wauer

Artur Schütz

Simon Bihler

Lexander Müller

In a method for detecting a motor phase fault of a motor arrangement, the motor phases of which are connected to a drive circuit having a DC voltage intermediate circuit and an inverter. A motor phase voltage at at least one of the motor phases with respect to a reference potential is captured while the inverter is switched off; and a voltage profile of the captured motor phase voltage is used to determine whether there is a motor phase fault on one of the motor phases of the motor arrangement.

Method for detecting a motor phase fault of a motor arrangement and drive circuit for driving an electronically commutated motor

A drive circuit for driving an electronically commutated motor contains a DC voltage intermediate circuit, and an inverter which is connected to the latter and has a bridge circuit containing a plurality of transistors, to which the motor phases of a motor configuration containing the motor can be connected. For detecting an insulation fault in the motor configuration, a positive or negative transistor of the inverter is switched on, while all other transistors of the inverter are switched off before all transistors of the inverter are switched off. A motor phase voltage of a selected motor phase of the motor phases with respect to a reference potential is then captured, while all transistors of the inverter remain switched off in order to determine whether there is an insulation fault on the motor phase on a basis of a voltage profile of the motor phase voltage.

Method for detecting an insulation fault in a motor arrangement, method for detecting a motor phase interruption in a motor arrangement, and drive circuit for driving an electronically commutated motor

A method controls a three-phase converter with a voltage intermediate circuit by pulse-width modulation for supplying a polyphase system, in particular a three-phase machine. The converter is operated with at least two different modulation methods which are selected from among the group of modulation methods which includes single-phase switching, two-phase switching and three-phase switching, and for changeovers to be made between the at least two different modulation methods depending on the operating state of the polyphase system.

Method for controlling a converter

The invention specifies a method for fault identification when driving a polyphase motor by means of a frequency converter, wherein, in a rest state, the frequency converter controls the phase voltages of the polyphase motor and the phase currents of the polyphase motor are measured. In this case, provision is made for, then in the rest state, the phase currents or current variables derived therefrom to be adjusted by closed-loop control to a predetermined setpoint current variable, for the frequency converter to be controlled so as to output an interference voltage variable for the phase voltages, for the response of the adjustment by closed-loop control to the interference voltage variable to be observed, and for a conclusion to be drawn regarding a fault of the frequency converter and/or the phases of the polyphase motor from the response of the closed-loop control. The cited method allows for largely loss-free detection of faults in the drive system of a polyphase motor. In the event of field-oriented closed-loop control, no additional complexity is required in the measuring device.

Method for fault detection in controlling a rotary field motor

A method for operating an electric motor with at least two motor terminals that are driven by a control device contains the steps of short-circuiting of at least two of the motor terminals of the electric motor by the control device; measurement of the motor phase currents at the short-circuited motor terminals; and identification of a standstill of the electric motor if a magnitude and/or a frequency of the motor phase currents measured lies below a predefined limit value. In the case of such a reliable identification of the standstill of the electric motor, an enable signal can then advantageously be generated in order, by way of example, to enable access to an apparatus driven by the electric motor.

Method for operating an electric motor and apparatus for performing the method

An internal unit of a washing machine or spin-dryer normally includes a washing container, which has a laundry drum mounted in the container such that it can rotate, and an electric motor for driving the laundry drum via a reduction gear, a transmission, or direct drive. The internal unit is suspended in a machine housing such that it can vibrate and constitutes an overall system which can vibrate in a damped manner and which is subject to unbalance-dependent resonance phenomena in specific regions of the rotational speed of the laundry drum. The causes of these resonance phenomena are vibratory movements due to momentary unbalances in the load in the laundry drum. To reduce these unbalance-dependent resonance phenomena, the internal unit is provided with a vibration sensor which is rigidly or substantially rigidly coupled to the internal unit

Internal unit, suspended such that it can vibrate, of a laundry treatment machine, method for controlling a laundry treatment machine, and use of an electronic sensor in an internal unit

A drive apparatus for a washing machine includes an electric motor, a drive shaft connected to the electric motor for rotary drive purposes and electronics for controlling operation of the electric motor. In order to achieve a compact construction, the electric motor and the electronics are integrated in a common unit. In order to increase operational reliability of the drive apparatus together with a simple construction, the common unit has a wall which is thermally coupled both to the electric motor and to the electronics and serves to dissipate heat. The electronics have a temperature sensor for detecting the temperature of the wall. Both the temperature of the electric motor and the temperature of the electronics can be monitored with this one temperature sensor.

Drive apparatus for a washing machine

A drive apparatus for a washing machine includes an electric motor, a drive shaft connected to the electric motor for rotary drive, a fan for cooling the electric motor and electronics for controlling operation of the electric motor. In order to achieve a compact construction, the electric motor and the electronics are integrated in a common unit, such as a motor housing. In order to protect the electronics and at the same time ensure that the electronics are sufficiently cooled, the common unit has a dividing wall, with the electric motor and a printed circuit board of the electronics disposed on opposite sides of the dividing wall. The dividing wall has at least one aperture. The electronics include power components protruding at least partially through the aperture and being in contact with the dividing wall and/or with a cooling air stream generated by the fan.

A method is specified for controlling a polyphase brushless electric motor, wherein the motor phase currents which are associated with the phases are produced by clocked variation of the respectively applied electrical potential. In this case, the motor phase currents flow back from the electric motor via a common return line with the peak current value in the return line being detected and being included in a controlled variable. Furthermore, a circuit configuration is specified, which is provided in a corresponding manner in order to carry out the control method. The control method and the circuit configuration allow the motor phase currents to be taken into account in the control of the electric motor in a simple and cost-effective manner.

Method and circuit configuration for controlling a polyphase brushless electric motor

A method is specified for controlling a multiphase motor that is commutated by an inverter-side bridge circuit, in the course of which a particularly precise and technically simple detection of a control-relevant variable of a considered motor phase, in particular of a motor phase current and/or a back EMF voltage and/or a variable derived therefrom, takes place. It is provided here to determine the control-relevant variable with the aid of the current state of a freewheeling diode that is disposed in a phase half bridge, assigned to the respective motor phase, of the bridge circuit, the current state being detected during an on time in which a power switch, connected in parallel with the freewheeling diode, of the phase half bridge exhibits a conducting state, and a power switch connected in series with the freewheeling diode exhibits a blocking state.

Method and device for controlling a multiphase electronically commutated motor

A circuit configuration for driving an electric motor, in particular of a washing machine, includes power switches connected to connection terminals of the electric motor and to a voltage intermediate circuit. A driver circuit is connected to the voltage intermediate circuit and to the power switches. A control unit, in particular a micro controller, is connected to the driver circuit. The control unit generates control signals for controlling at least one rotation speed of the electric motor. The driver circuit generates short-circuit control signals for driving the power switches, which bring about a short circuit of the connection terminals connected to the power switches, independently of the control signals from the control unit. The driver circuit generates the short-circuit control signals as a function of a detection of an overvoltage of the voltage intermediate circuit over a desired voltage range. A method for controlling an electric motor is also provided.

Circuit configuration and method for controlling an electric motor, in particular of a washing machine

In order to be able to implement higher rotary spin speeds without structurally endangering the machine, a characteristic value that is as accurate as possible for the currently prevailing drum loading is desirable, for loading-dependent rotary speed limitation. Acceleration to a spin speed is interrupted in order to measure the respective electrical power consumption of the drive motor for a given rotary speed and then for a lower rotary speed that does not lead to the further removal of water from the laundry in the drum. Then the energy requirement and the acceleration period back up to the given rotary speed are measured, before the drum is accelerated to spin speed. The latter is to be limited in load-dependent manner, namely in accordance with the instantaneous mass moment of inertia of the drum, which is proportional to the acceleration energy less the frictional energy during the acceleration phase, formed from the average value of the two friction powers measured at constant rotary speeds and the acceleration period.

Method of determining the loading of the drum of a laundry treatment machine

A circuit configuration and a method for determining a current drawn from a mains by a converter through a dc voltage intermediate circuit, replaces a required pulse-resistant input current measuring resistor with a conductor track of the circuit configuration itself. Since the input current drawn from the mains by the dc voltage intermediate circuit is on average equal to the output current delivered to the converter, the present resistance of the conductor track is given by the resistance of the measuring resistor downstream of the dc voltage intermediate circuit, weighted with the quotient of the input and output voltage drops. In that way, the mains current and therewith the power factor can be influenced by way of a current limiter without requiring an expensive pulse-resistant special resistor for mains current measurement.

Circuit configuration and method for measuring and limiting currents

Before a washing machine is switched over to a very high spin speed in the spin program of the washing machine, the existing imbalance due to irregular distribution of laundry in the drum should be checked. If the imbalance is too strong, the spin program should be interrupted if there is a threat of excessively high bearing forces to be expected. The fluctuation in rotary speed, which may have a high frequency due to the drum speed, and of the power consumption of the washing machine motor measured downstream of the direct current intermediate circuit prior to the feed thereof into the inverter for producing the rotary field in the motor. There, the vector product of the current and the voltage for imbalance measurement by determining power is blocked off from mains network interference effects by the high capacitance of the direct current intermediate circuit.

Method of determining the imbalance of a laundry drum

A large domestic appliance has main and auxiliary drives () thereof supplied from the same dc voltage intermediate circuit () which is provided only once, by way of change-over switch sets (), by half-bridge circuits (). For that purpose a frequency converter () with its bridge circuit () for the main drive () is switched over in single-pole or multiple mode to the rotary field motor () of the auxiliary drive () by way of a change-over switch set () connected in its output-side motor lines (); or in the frequency converter () two half-bridge circuits () which are associated with the main and the auxiliary drives () are operated in parallel from the dc voltage intermediate circuit ().

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Bad Waldsee, Germany

Martin Weinmann