Abstract: There is described a method for controlling a quenching device for a converter bridge with line regeneration, whereby the converter bridge controlled by a network-timed control circuit by ignition pulses is connected with its three inputs to the phases of a three-phase network and the two outputs of the bridge are connected to a direct-current motor which feeds, when operated as a generator, current back to the three-phase network via the bridge. The quenching device is controlled by a trigger unit which emits trigger pulses depending on the monitoring of electrical and temporary variables. The quenching device comprises, for each bridge half, a quenching condenser that can be charged by a charging circuit quenching voltage. The quenching condensers, in the event of quenching, can be connected to the bridge halves by means of switches that are controlled by the trigger unit.

Abstract: There is described a method for controlling a quenching device for a converter bridge with line regeneration, whereby the converter bridge controlled by a network-timed control circuit by ignition pulses is connected with its three inputs to the phases of a three-phase network and the two outputs of the bridge are connected to a direct-current motor which feeds, when operated as a generator, current back to the three-phase network via the bridge. The quenching device is controlled by a trigger unit which emits trigger pulses depending on the monitoring of electrical and temporary variables. The device has measuring values “direct output current” and/or “supply voltages” used to determine characteristic values which are compared with theoretical characteristic values. Depending on the result of said comparison, the quenching device is optionally activated.

Abstract: There is described a method for controlling a quenching device for a converter bridge with line regeneration, whereby the converter bridge controlled by a network-timed control circuit by ignition pulses is connected with its three inputs to the phases of a three-phase network and the two outputs of the bridge are connected to a direct-current motor which feeds, when operated as a generator, current back to the three-phase network via the bridge. The quenching device is controlled by a trigger unit which emits trigger pulses depending on the monitoring of electrical and temporary variables. The quenching device comprises, for each bridge half, a quenching condenser that can be charged by a charging circuit quenching voltage. The quenching condensers, in the event of quenching, can be connected to the bridge halves by means of switches that are controlled by the trigger unit.

Abstract: There is described a method for controlling a quenching device for a converter bridge with line regeneration, whereby the converter bridge controlled by a network-timed control circuit by ignition pulses is connected with its at least three inputs to the phases of a three-phase network and the at least two outputs of the bridge are connected to a direct-current motor which feeds, when operated as a generator, current back to the three-phase network via the bridge. The quenching device is controlled by a trigger unit which emits trigger pulses depending on the monitoring of electrical and temporary variables. The device has measuring values “direct output current” and/or “supply voltages” used to determine characteristic values which are compared with theoretical characteristic values. Depending on the result of said comparison, the quenching device is optionally activated.

Abstract: A protective circuit (SCH) for a line-commutated thyristor bridge (B, B?), which is designed for feeding energy of a power circuit connected to the bridge and also for feedback from this circuit, and which is connected between the thyristor bridge and the power circuit. In a series branch of the protective circuit, there is at least one IGBT transistor (GT1, GT2), which is biased in the feedback direction with an inverse-parallel diode (D1, D2; D1p), and which can be deactivated for the appearance of a tipping recognition signal (sk, Us1), which is supplied by a control circuit (AST) associated with the transistor.

Abstract: A protective circuit (SCH) for a line-commutated thyristor bridge (B, B′), which is designed for feeding energy of a power circuit connected to the bridge and also for feedback from this circuit, and which is connected between the thyristor bridge and the power circuit. In a series branch of the protective circuit, there is at least one IGBT transistor (GT1, GT2), which is biased in the feedback direction with an inverse-parallel diode (D1, D2; D1p), and which can be deactivated for the appearance of a tipping recognition signal (sk, Us1), which is supplied by a control circuit (AST) associated with the transistor.

Abstract: A device for controlling the field current of a DC motor supplied from an AC network and which is operated beyond the normal speed of the DC motor in the higher speed range obtainable by weakening of the field of the DC motor, there being provided for the apportioning of the field current of the DC motor a phase angle control circuit which is operated depending on a control variable obtained from the respective measured speed of the DC motor by a function-forming device as a function of the speed, the function-forming device comprising a function memory which contains values of the control variable correlated to individual speed values stored in a matrix in tabulated form, the correlation of these values individually corresponding to the DC motor being established when the DC motor starts up for the first time, and where a constant dependence of the control variable on the speed is established either by a polygonal line obtained by linear interpolation from the value pairs stored in tabulated form or by a cur

Abstract: For controlling d-c motors which are supplied with an armature current obtained by phase gating, the bucking voltage induced in the motor is particularly well suited. This voltage is calculated indirectly by a measuring unit which calculates the instantaneous bucking voltage of the d-c machine as a function of the phase gating angle calculated in the preceding computing cycle, the measured current conduction angle, the measured magnitude of the line voltage, the mean armature current value and the armature circuit resistance specific to the machine and the armature circuit inductance specific to the machine.