CS231507B1 - Connexion for signalization of current limiting in automatic control systems - Google Patents

Abstract

Connection for Restricted Signaling current in the control circuits logical output, transient signaling the state of the control circuit when it is the control circuit current to the constraint that the voltage is sensed at the collector resistors. The sensed voltage is further evaluated in comparators with hysteresis and modified in the output circuit for the output logic signal at TTL and DTL level. engagement can be used in all regulatory unidirectional and alternating circuits drives where transistor is used current limiter.

Description

The circuit for signaling the limited current in the control circuits provides logic outputs, signaling the transient states of the control circuit when the control circuit current is limited by sensing the voltage at the collector resistors. The sensed voltage is further evaluated in comparators with hysteresis and adjusted in the output circuit for the output logic signal at TTL and DTL levels. The wiring can be used in all DC and AC control circuits where a transistor current limiter is used.

The present invention relates to the connection of a pre-filamentate of a limited number of birds in irregular multidirectional circuits of DC and AC drives.

There are known wiring where BsObithé dhima provides current from the sensor and a separate control deviation signal, the two signals being compared and evaluated. Such wiring is complex and poorly reliable.

These drawbacks are eliminated by the limited current signaling circuits in the control circuits of the present invention, which are based on the fact that the hysteresis comparators are connected via their inputs to the collector resistors while their outputs are connected to the evaluation circuit, with one collector resistor connected to one end. a resistor divider via a positive reference voltage source and a second collector resistor connected at one end to the resistor divider via a negative reference voltage source, while the other ends of the collector resistors are coupled to the collector transistor collectors connected between the replacement controller and the current regulator.

Such wiring is simple and reliable.

In FIG. 1 shows an example of a circuit for limiting current signaling in control circuits.

The basic part of the signaling is comparators with hstephysics, which serve for sensing voltage drop and its polarity from the collector resistors 3, 4. The evaluation circuit 5 serves for processing the output signals 13, 23 from the compressors with hysteresis 1, 2 and for adjusting the logic output. signal to TTL or DTL logic level. The circuit further comprises potentiometers 9, 10, which together with the reference voltage sources 6, 8 serve to adjust the value of the limited current. The current setpoint limiter 7 is coupled together with the controller 11 and the voltage regulator 12 in the drive control circuit.

On the resistor divider 9, a voltage value is set which corresponds to the desired current current, e.g. during start-up and at the resistance divider 10 during braking. The reference voltage sources 6, 8 maintain these set values at a constant precise level and form hard sources for supplying the collector resistors 3, 4.

With small signal changes in the control circuit at the output of the master controller 11, the voltage is lower than on the collectors of transistors 71, 72, which are in the active region at this stage. Only a small current flows from the collector resistors 3, 4 from the reference source 6, 8 to the input of the current regulator 12. At the same time, the voltage drops on the collector resistors 3, 4 are also small and the comparators with hysteresis 1, 2 are swiveled.

In the event of large signal changes in the control circuit, during start-up or braking, a higher absolute voltage value is generated at the output of the master controller 11, as set on the resistors 9 or 10. The transistor 71 or 72 goes into the inverse region. The difference in this voltage changes the direction of the current through the collector resistor 3 or 4, with the comparator having hysteresis 1 or 2 swiveling to the operating state. The output 13 or 23 transfers the signal to the evaluation circuit 5, where it is adjusted to the TTL or DTL level and can control the logic of the control circuit. The logic pulse at the output of the evaluation circuit 5 lasts as long as the drive control circuit is limited.

Such wiring can be used to timing the time when the drive current is limited and to block the digital speed correction in the transient states of DC and AC drives.

SUBJECT

Claims (2)

The circuit for signaling the limiting current in the control circuits is characterized by the fact that the circuit with the current (1, 2] They are connected by their inputs (11, 12, 21, 22) to the collector resistors (3, 4) while their outputs (13, 23) are connected to the evaluation circuit (5) »wherein the first collector resistor (3) is the one end connected to the resistive length (9) via the positive reference voltage source (6) and the long collector resistor (4) is connected to the resistive divider (10) by the third condenser and the negative reference voltage source (8) while the other ends of the collector resistors (3) 4] are connected to the collectors of transistors (71, 72) of the limiter (7), which is connected between the master controller (11) and the re-