Siemens Aktiengesellschaft

Firma Carl Freudenberg

Siemens Aktiengesellschaff

Diethard Runggaldier

Gerd Griepentrog

Bernhard Streich

Reinhard Maier

Johann Seitz

Norbert Mitlmeier

Dirk Hertz

Norbert Elsner

Andreas Fritsch

B Claus Doerwald

Peter Kaluza

Wilfried Jaehner

Marco Dornauer

Stefan Zitzler

Christian Schreckinger

Marcel Benecke

Bruno C Doerwald

Alexander Müller

Reinhard Herbst

Lynn Johnson

Franz Ultsch

Peter Heider

Synchronous motors are controlled using a three-phase AC power controller. According to at least one embodiment of the invention, a fundamental wave having the desired frequency is defined for the first phase, and corresponding fundamental waves which have the same frequency as the frequency in the first phase but are out of phase by specific values are defined in the other phases. The triggering times during which the generated current pulse concurrently has the same polarity as the respective fundamental wave in two of the phases are determined for each phase and are used. Two of the three fundamental waves are generated in phase opposition when the desired frequency amounts to half the system frequency.

Method for the operation of synchronous motors, and associated device

A method is disclosed for slowing-down control of an asynchronous machine, wherein the value of a start energy is determined and stored while the asynchronous machine is being run up from being stationary to the operating rotation speed. The asynchronous machine is braked, in the reversing mode, with braking energy which corresponds to the start energy multiplied by a correction factor wherein the correction factor assumes a value between 0 and 1. In at least one embodiment, the asynchronous machine is braked further by DC braking after braking has been carried out in the reversing mode.

Method for slowing-down control of an asynchronous machine

Disclosed is an electromagnetic switching device including a number of fixed contact pieces, a solenoid-operated mechanism, a contact support which can be moved counter to restoring devices in at least one embodiment, with the aid of the solenoid-operated mechanism and on which a number of movable contact pieces are arranged, and an off stop for the contact support. A sensor is provided, in at least one embodiment, for detecting the position of the contact support while a control unit is provided which is connected to the sensor and regulates and/or controls the solenoid-operated mechanism during a switch-off process in order to decelerate the contact support before the same hits the off stop. Also disclosed is a method for operating such a switching device. The contact support, in at least one embodiment, transmits only a small momentum to the off stop, thus reducing the load applied to the involved parts. Such a switching device therefore has a longer service life than conventional switching devices.

Electromagnetic switching device and method for the operation thereof

A method is disclosed for operating a two-phase rotary current controller. In order to optimize the operation of a two-phase rotary current controller, magnitudes of a parameter that can be varied in both controllable phases of a two-phase rotary current controller is matched in these phases. In particular, the existing principle of phase-symmetric control with a uniform ignition delay in both controlled outer conductors is abandoned, and a separate ignition delay is stipulated for each of the two controlled outer conductors.

Method for operating a two-phase rotary current controller

Control part of an electronic device

An input voltage contacted at the input of a contact can be through-connected to an output of the contact or switched off via a movable contactor. In order to determine the switching state of the contact, any drop in the contact voltage between the input and the output is detected. By the detected contact voltage, it can at least be determined whether the input voltage has been through-connected to the output or switched off.

Method for determining the switching state of a contact and evaluation circuit corresponding thereto

A method with which the load current and thus the load moment of an asynchronous motor that is controlled via a phase-controlled two-phase thyristor power controller, can be easily influenced so as to allow a smooth starting operation. According to a first embodiment, the ignition point is determined in the controlled phase in order to adapt the flow angles of the subsequent current half waves. According to a second embodiment, the ignition point of the subsequent current half waves is brought forward in both controlled phases.

Method for reducing the influence of a DC current component in the load current of an asynchronous motor

Asynchronous motors are controlled by way of two- or three-phase controllers that include at least two pair of thyristors connected in antiparallel and fired at certain intervals. According to the inventive method, a fundamental wave with the desired frequency is defined for the first phase and in the other phase a respective fundamental wave is defined that has the same frequency as that in the first phase, but phase-shifted by corresponding values. For every phase, firing intervals are marked that have the same polarity as the respective fundamental wave. Those intervals of the potential firing intervals are used for every phase at which there is a potential firing interval in one of the two other phases. These intervals are used as the actual firing intervals.

Method for operating asynchronous motors and corresponding device

Reduced tensioning time for electronically controlled switch contactors

An electromagnetic switching device includes a contact arrangement with three contacts which couple a three-phase load to three phases of a three-phase power supply system, and disconnect the three-phase load from the three phases. Switching erosion takes place on the contacts. An overall erosion is determined for each contact, and is supplied to a drive circuit. The contact arrangement is operated by the drive circuit as a function of the overall erosion such that the overall erosion of the contacts are approximated to one another.

Method for averaging out overall burn up in an electromagnetic switching device and a corresponding electromagnetic switching device

In order to control the run-down of an induction machine, whose stator is connected to a singe-phase or polyphase AC main power supply system via an AC power controller which can be controlled by phase gating, a phase gating angle is first increased in steps until an operating point is reached, which is defined on the basis of predetermined criteria. The phase gating angle is then controlled in order to ensure that the induction machine runs down in accordance with a predetermined control program.

Method and device for controlling deceleration in an induction machine

In a method and device for determining the torque of an induction machine, stator terminal voltages and the stator terminal currents are integrated and then high-pass filtered to determine a space vector of the concatenated stator flux. The torque is calculated therefrom by multiplication by a complex correction factor.

Method and device for determining the torque of an induction machine

A method for identifying a rotation direction of a three-phase network includes the steps of sampling the individual phases at given times and using an evaluation algorithm to evaluate the measured values or interpolated approximate values, or only the mathematical signs of the values, in order to determine the rotation direction. In addition to the basic method for an ideal signal profile, half-wave-rectified signal profiles of individual phase conductors can preferably be evaluated. The method can advantageously be used to detect the rotation direction with a digital overload relay, using a digital signal control and/or signal processing which is already provided in the digital overload relay.

Method for detecting a rotation direction in three-phase networks

In order to measure the rotation speed of an induction machine whose stator is connected via a controllable AC controller to a single-phase or polyphase AC power supply system, the stator is disconnected from the AC power supply system for at least a predetermined time period (&Dgr;t). This is preferably achieved by opening active devices in the AC controller, with at least one stator voltage, which is induced in the stator by the rotary movement of the rotor, being measured in this time period (&Dgr;t). The measured values are used to determine the frequency of the stator voltage and to derive the rotation speed of the induction machine.

Growing community of inventors

Stegaurach, Germany

Diethard Runggaldier