CS231507B1 - Connection for restricted current signaling in control circuits - Google Patents

Abstract

The circuit for signaling the limited current in control circuits provides a logic output for signaling the transient states of the control circuit when the current of the control circuit is limited by sensing the voltage on 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 circuit can be used in all control circuits of DC and AC drives where a transistor current limiter is used.

Description

BACKGROUND OF THE INVENTION The present invention relates to a coupled feeder device for limiting circuits in control circuits of unidirectional and alternating drives.

Connections are known where the BsObithé conducts the current from the sensor and signals the control deviation signal while comparing and evaluating the two signals. Such connections are complex and not reliable enough.

These drawbacks are eliminated by the current limiting signaling circuits in the control circuitry of the invention, the principle of which is that the hysteresis comparators are connected to the collector resistors with their inputs while their outputs are coupled to the evaluation circuit, with one collector resistor connected to a resistive divider through the positive reference voltage source, and the second collector resistor is connected at one end to a resistive divider through a negative reference voltage source, while the other ends of the collector resistors are coupled to the limiter collectors connected between the alternate regulator and the current regulator.

Such involvement is simple and reliable.

FIG. 1 illustrates an exemplary circuit for signaling a constrained current in a control circuit. The basic part of the signaling are comparators with a power factor which serves to detect the voltage drop and its polarity from the collector resistors 3, 4. The evaluation circuit 5 serves to process the output signals 13, 23 from the comers with the hysteresis 1, 2 and to adjust the logic output signal to TTL or DTL logic. The connection further comprises potentiometers 9, 10, which together with the reference voltage sources 6, 8 serve to adjust the current-limited value. The setpoint limiter 7 is coupled with the 4 quenched controller 11 and the flow controller Ϊ2 in the drive circuitry.

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

In the case of small signal changes in the control circuit at the output of the master controller 11, there is less voltage than at the collectors of transistors 71, 72 which are in this phase in the active region. Only a small current flows from the reference port 6, 8 to the current regulator input 12 through the collector resistors 3, 4. The voltage drops at the collector resistors 3, 4 are also small and the comparators with the hysteresis 1, 2 are turned into a rest state.

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

Such a connection can be used to delay the time when the drive current is limited and to block the digital speed correction in the transients of unidirectional and AC drives;

Claims (2)

SUBJECT CONNECTIONS FOR RESTRICTED REDUCTION IN REGULATORY CIRCUITS ARE FACILITATED BY THAT INCLUDING THAT WORKING WITH THE PERSONNEL (1, 2] They are connected to their collector resistors (3, 4) with their inserts (11, 12, 21, 22) while their outputs (13, 23) are connected to the evaluation circuit (5) »while the first collector resistor (3) is the one the end connected to the resistor divider (9) via the positive reference voltage source (6J and the tapered collector resistor (4), the conductor connected to the resistor divider (10) is the negative reference source (8) while the other end of the collector resistor (3, 4) ) are connected to the collectors of the transistors (71, 72) of the limiter (7), which is connected between the master controller (11) and the current regulator (12). Fig <1