DE3018327C2 - Procedure and arrangement for testing the control and regulation functions of a speed-controlled drive - Google Patents

Description

2. Arrangement for performing the method according to claim 1, characterized in that all Connections and switchover points required for the test within the operating control circuit to an open diagnostic connector (31) and then over this and an attachable so Test device (30) with passive components, voltage transmitters and key sets (32) the operating control circuit can be switched over to the test and applied externally

3. Arrangement according to claims 1 or 2, r ~> characterized in that the control loops to be interrupted for testing between the armature current controllers (3a, 3b) and d *, m speed controller (2) during the test by negative feedback networks in which only Resistors (34a, 3Ab) w are closed.

4. Arrangement according to claim 3, characterized in that the resistors (34a, 3Ab) required for the production of the test circuit for the negative feedback are accommodated on plug-in cards of the operational «system.

5. Arrangement according to claims 1 or 2 with a field current regulator and a field weakening device, characterized in that the field current regulator (17) has its input connected to the w operational field weakening device (20) and a field current setpoint transmitter (18) are connected, receives its input voltage from the inverter (33) and via a feedback resistor (35) its output is connected

6. Arrangement according to claim 5, characterized in that the feedback resistor (35) with is housed on a plug-in card of the operational system

7. Arrangement according to claim 2, characterized in that that via a switch (32/7,) of the key set (32) that of the regular actual value transmitter for the excitation current separate threshold value element (24) for the excitation current with a test signal can be acted upon

8. The arrangement according to claim 2, characterized in that a switch (321) of the key set (32) of the separate from the regular actual value transmitter for the armature current anti-slip protection (12) can be acted upon with a test signal

9. Arrangement according to claim 2, characterized in that over separate switches (32Λ, 32k) of the key set (32) the electrically from the safety switches of the semiconductor bridges (4a, Ab) separate pulse amplifier stages (9a 1,9a 2 and 9b 1,96 2 ) can be acted upon with blocking signals.

10. The arrangement according to claim 2, characterized in that the threshold element for overcurrent (25) which influences the armature current regulator (3a, 3b) is disconnected from its previous control lines and via a switch (32e) of the set of buttons (32) with an "overcurrent" -Signal can be acted upon

11. Arrangement according to claim 2, characterized in that the pulse generator stages (8a, 8b) fed by the armature current regulator (3a, 3b) can be supplied via separate switches (32a 32j) forcing pulses and pulses for commutation locking.

12. The arrangement according to claim 2, characterized in that the pulse monitoring (29) influencing the pulse generator stages (8a, Sb) can be acted upon by unlocking pulses via a switch (32 /? Of the key set (32))

13. The arrangement according to claim 2, characterized in that instead of the semiconductor temperature monitoring via a switch (32a) of the key set (32) of the speed controller (2) can be influenced with a test signal.

14. Arrangement according to claim 2, characterized in that test switches (326 and 32c) of the key set (32) are provided for simulating controller blocking pulses, which via threshold value elements (38, 39) for actual speed values and speed setpoints and a logic element (40) on the speed controller (2 ), Armature current regulator (3a ^ and field current regulator (17) act.

15. The arrangement according to claim 2, characterized in that a switch (32g) of the key set (32) can influence the frequency switching (36), which is connected to an auxiliary voltage via insert (32 ^) of the test device (30).

16. The arrangement according to claim 2, characterized in that a switch (32m) of the key set (32) a direct switch (41) to the speed setpoint for braking operation can be carried out.

The invention relates to a method for testing the control and regulating functions as well special additional influencing variables within a speed-controlled drive with subordinate armature current control. In the known drives of this type with analog control and regulation devices and the Use of converters as power control elements, e.g. B. on electric railways, must be used for a functional test sensitive cables are led out of the control cabinet to the test device. That is not only cumbersome, but also brings problems with regard to possible electromagnetic coupling. In addition, the exam is sometimes only after

The power unit can be connected to the high voltage.

For such drives there is therefore a need to carry out the control in a simpler and more fail-safe manner can, whereby the operational signal flow are not significantly changed and also no need for high voltage SHOULD exist

This object is achieved for a method of the type mentioned according to the invention in that in the high-voltage-free switched-off state of the drive to the armature current regulator above a fictitious Armature current setpoint is fed from an inverter that is fed by the speed setpoint. That continues the speed controller receives a fictitious actual speed value via feedback from the output of the Armature current controller is supplied and that by means of variation of the speed setpoint and the input external signals or impulses to associated operational threshold value or functional element T the effectiveness the essential influencing variables on speed setpoint generation and the controller can be checked.

In an advantageous arrangement for carrying out the method, all are for this purpose for the test necessary connections and switching points within the operating control circuit to an open diagnostic connector guided and via this and a plug-in test device with exclusively passive components, The operating control circuit can be switched to test and external to the voltage sensors and key sets can be charged.

The possibility of a malfunction of the test device itself was minimized and the effort for technical Realization of the test circuit kept low. The test device can be small, easy to handle and cheap are executed. The test can be carried out without high voltage on the power control element and can be done with trainees be performed.

In an expedient embodiment, the control loops to be interrupted for testing are between the Armature current regulators and the speed regulator during the test through negative feedback networks in which there are only resistors, closed. It can be advantageous for the production of Resistances required for the negative feedback on the plug-in cards of the test circuit be housed in the operational system.

Advantageously, in an arrangement of the type mentioned with a flow current regulator and a field weakening device, the field current regulator has its input connected to the operational field weakening device and a field current setpoint generator, receives its input voltage from the inverter and is connected to its output via a feedback resistor. Here, too, the feedback resistor is expediently accommodated on a plug-in card of the operational system. Using switches in the key set, essential threshold value and function elements can be addressed directly with test signals, which is further evident from the claims and the description of the example

The invention is explained in more detail below with the aid of circuit examples to be evaluated schematically explained it shows

1 shows a converter-fed mixed current drive in a simplified block diagram,

F i g. 2 the associated test circuit.

Before the actual test circuit according to the invention and its operating method can be described, the circuit to be tested must be discussed. According to FIG. 1, the speed of a motor 1 is controlled via a common speed controller 2 with a subordinate armature current control divided into two channels (a and b) with the armature current regulators 3 and 3b, as well as a sequential circuit of two asymmetrically half-controlled converter pulse bridges 4a, Ab. Via a potentiometer 5, a speed setpoint W _{n is} specified for this purpose, and in point 6 with an actual speed value

ι ο X _n compared. The difference is given to the speed controller 2. Its output corresponds to the armature current value WiA, which is compared in points 7a and Tb with the armature current values Xn of the two channels and fed to the armature current regulators 3a and 3b.

The outputs of the armature current regulator 3a and controlling 3b practice; - Impulsbildnerstufen 8a and 86 and pulse amplifier stages 9 ai, 9 _a2 and 9 * ι and 9 ", the controllable valves of the converter bridges 4a and down the output voltage of the speed controller 2, the.

: o Corresponds to the armature current value, is also used by the four system variables speed setpoint value, actual speed value, Motor temperature (via function block 13) and valve temperature (via switch 14) influenced. Your maximum value «v is determined by the maximum armature current

r> limit (voltage divider block 15) limited. The motor current setpoint is limited via the constant amplifier 11 is used to limit the starting torque and the armature current value is set via anti-skid protection 12 influenced so that at low speeds it

Ki speed remains below the maximum armature current limit and can only reach the maximum armature current limit with a relatively large gain after an adjustable limit speed has been exceeded. The converter bridges 4a and Ab are

ü Usually controlled one after the other. For this purpose, the current regulator 3a influences the current regulator 3b via a comparator 16.

The field current control via the valves 21 ^; st implemented as a fixed value control with a field current regulator 17 to which a setpoint voltage divider 18 is connected and which controls the valves 21 via pulse generator stages 26, 27, 28. Is a certain speed setpoint reached and. if the actual speed value has exceeded the threshold of a threshold value element 19, a

4> Field weakening device 20 (characteristic element) effective. Strength and speed range are adjustable. There are still numerous functional elements for the arrangement Monitoring assigned. The speed setpoint can be blocked via an OR gate 21. On the

> o OR gate 21 is in the sense of this blocking (i.e. to Bring zero) the control of the main switch 22 (if the locomotive is not upgraded), a temperature monitor 23 z. B. from an electronics cabinet, a threshold value element 24 for the excitation current at under-

exceeding the threshold value and an overcurrent block for the armature current actual value via threshold value element 25 placed.

For the actual test procedure, reference is made to the circuit according to FIG. 2 pointed out. The reference symbols are

bo, as well as similar components, remained the same. The converter valves of bridges 4a and 4b do not need high voltage for the test, ie motor 1 does not carry any current. The normal actual armature and field current values

fai are missing. They are replaced by fictitious values. The inputs of the armature current regulator 3a and 3b for the armature current actual value are when a test device 30 is connected to a diagnostic connector 31, of which only

the set of buttons 32 is shown, interrupted and the output of an inverter 33 is looped in, which outputs the fictitious armature current actual value. The inverter 33 is ultimately fed by the operational speed setpoint (potentiometer 5). Likewise, fictitious actual speed values are now fed to the common speed controller 2 via point 6 via feedback, namely via the resistors 34a and 34f> from the outputs of the armature current controllers 3a and 3b. A stable state can thus be established in the voltage control loop that has been created in this way. The setpoint for the speed controller 2 is the same as set in the operational circuit to the set value potentiometer 5, however, the desired value for the armature current controller 3a and 3b does not come now more from the output of the speed controller 2, but forward inverter 33, whose input variable is the speed setpoint. In the steady, steady state, the output voltage of the speed controller 2 is thus equal to the speed setpoint voltage. The output voltages of the current regulators 3a and 3b , on the other hand, are dependent both on the speed setpoint voltage and on the feedback resistors 34a and 346 . In the transition area in which both current regulators 3a and 3b are involved in the formation of the actual speed value, the circuit is unstable. However, as soon as the current regulator 3a of the bridge 4a or 3b of the bridge Ab is locked, the situation is clear again and therefore stable.

Checking the effectiveness of the influencing variables on the anti-skid protection 12, the maximum armature current limit (voltage divider block 15), the run-up limitation (constant amplifier 11), the semiconductor temperature switch 11 for overcurrent and field current monitoring (welding value element 24) on the speed setpoint generation, the speed controller 2 and the armature current controller 3a, 3b , boxes 32a to π of key set 32 can be checked here by setting different speed setpoint voltages or by actuating corresponding test device switches. It is not possible to check the engine temperature in this way.

The field current regulator 17 is also disconnected from its operational actual value line by connecting (plugging in) the test device 30. It becomes a first-order delay element through feedback with the resistor 35. Its input voltage also comes from the inverter 33 and can therefore be adjusted with the speed setpoint potentiometer 5. Its output voltage is influenced by the feedback resistor 35, the field weakening device 20 and the field current setpoint voltage divider 18. The functioning of the field weakening device itself remains unchanged.

As can be seen, the signal flow of the pulse formation and amplification remains essentially unaffected by the test circuit. The synchronization voltage for the triangulation (frequency switching block 36) is supplied by the normal 220 volt alternating voltage network 20 to 60 Hz via the test device 30 from the insert 32 *. The operational synchronization transformer (37 in Fig. 1) is short-circuited. The thyristors of the converter bridges 4a and Ab receive their normal ignition pulses in the test circuit. The commutation lock can be controlled via the corresponding switch 32j of the test device 30.

The following list shows those assigned to the other monitoring functions Switches and buttons.

Monitoring function switch /

button

Valve temperature monitoring (at 14) 32a

Controller inhibit speed actual value 326

Controller inhibit speed setpoint 32c

Main switch control (instead of 22) 3Id

Overcurrent lock (at 3a, 3b) 32e

Pulse monitoring 32 /

Frequency switching (at 36) 32g

Fuse monitoring (bridge Aa) 31h

Fuse monitoring (bridge Ab) ilk

Forced pulses (at 8a, Sb) 32 /

Commutation lock (for Sa, Sb) 32 /

Anti-skid 12 32 /

Switchover braking circuit (at 41) 32m

Field current monitoring (with 24) 32n

The invention makes it easy and quick to monitor the temperature of the electronics all individual functions of the monitoring via corresponding switches or keys 32 of the test device 30 independently verifiable. The vehicle or the drive does not need to be in operation and skilled workers are not required for the exam.

For this purpose 2 sheets of drawings

Claims (1)

15 claims: 1. Procedure for testing the open-loop and closed-loop control functions as well as special additional influencing variables within a speed-controlled drive with subordinate armature current control, d a through characterized that in the high-voltage-free switched-off state of the drive - the armature current regulator (s ) (3a, 3b) is supplied with a fictitious armature current setpoint from an inverter (33) which is fed by the speed setpoint, - A fictitious actual speed value is fed to the speed controller (2) via feedback from the output of the armature current controller or controllers (3a, 3b), and - By varying the speed setpoint and input of external signals or pulses to associated operational threshold value or function elements, the effectiveness of the essential influencing variables on the speed setpoint formation and the controller (2, 3a, 3b, 17) can be checked.