Device for check-up of tram and trolleybus electric apparatuses
FIELD: electric measurements, applicable in check-up of tram and trolleybus electric apparatuses in the process of manufacture and in service.
SUBSTANCE: current in the current source is fed to the current winding of the current relay from the rectifier via a key, choke, shunt. The device uses a pulse-width modulator that controls the keys, slowly varying voltage is applied to the modulating input of the pulse-width modulator that is preliminarily modulated by the rectifier ripple voltage. Besides, use is made of a sample-release circuit of operate (release) currents and voltages. The signals from these circuits are fed to indicators via analog-to-digital converters.
EFFECT: reduced error of determination of operate and release current and voltage relays, enhanced capacity of check-up in the device due to reduced ripples of the source of smoothly varying current.
2 cl, 4 dwg
The device relates to the field of electrical measuring and checking electrical quantities, in particular voltage and current actuation and release of the relay DC. Can be used in the manufacture, repair and control devices protection and control of trams and trolleybuses.
A known device for testing electric vehicles trams and trolleybuses (leaflet Voronezh experimental mechanical plant. Russia, 394055, Voronezh, street 121 Infantry division, 9, tel/Fax : (0732) 36-48-75, dated 02.07.2002,). The stand contains a starter, switch machine, ammeter, voltmeter, manual controls current and voltage (Latry laboratory autotransformers), the signal lamp.
The disadvantage of the stand, according to the authors, is a large error in the determination of current and voltage actuation or release of the relay, due to the fact that the current and voltage on the test apparatus of the change by hand, turning the engine Later, and it does not provide the smoothness and monotonicity change settings. In addition, the voltage or the current operation of the apparatus, the operator observes arrow on the meter (ammeter, voltmeter), which has significant inertia.
When adjusting devices for monitoring the current (voltage) operation must be repeated several times, and when manual methods for the e change of current (voltage) it requires a considerable investment of time. Low performance testing apparatus is also the disadvantage of the stand.
A known device for testing devices tram and trolley-bus, developed by the Academy of municipal economy to them. Kdepimlibs and produced Nevinnomyssk Electromechanical plant (see TO RSFSR 2.151-87. Stand for testing devices tram and trolleybus 0-267. Technical conditions. Technical description). This stand, selected as a prototype, contains a power supply unit for testing high-voltage relay unit for testing high-current devices, measuring current and voltage in the form of analog devices, control buttons, indicator lamps, forming the control unit. This stand has the disadvantages of the above stand, because the change of the current (voltage) is also produced by the operator by turning the handles of the controls and the test results are observed on analog devices.
To reduce the measurement error of current and voltage actuation (release) devices, and to reduce time spent on control devices, in the known device in the current block between the output of the rectifier and inductor placed in series, the first power switch, and between the common point of the first key and the inductor and a common output of the second rectifier si the new key. The control input of the first key is connected to the output of pulse-width modulator (PWM) and the input of the inverter, and the control input of the second key is connected to the inverter output. Modulating the PWM input connected to the output of summing amplifier, a first input which corresponds to the amplifier and decoupling element such as a capacitor, is connected to the output of the rectifier and the second input of the summing amplifier connected to the output of the standby generator. The input of the generator is connected to the control input of the current block, the starting PWM is connected to the output of the clock generator. This high performance unit allows a wide range to smoothly change the current in the winding of the test apparatus in an automatic mode.
The proposed solution allows to reduce ripple current 3-phase period of the rectifier winding apparatus at the expense of the tracking control pulse duration of the current through the power switches.
Measuring current and voltage have the first and second channels each, with each channel input is enabled schema of the sample-hold informational inputs which are connected to information inputs of the meter, and the control inputs of circuits sample-and-hold in the first channels of both meters are connected to the first control inputs of the meter, and the second channel with the second Manager of the inputs of the meter, the first control inputs of the meter are connected with the third output of the control unit and the second control inputs of the meter are also connected with each other and with the fourth output of the control unit. In each channel, the output of the circuit of the sample-hold through analog-to-digital Converter is connected with the corresponding indicator.
All the elements of the device on supply input connected to the output of the power supply. This design allows for parallel-loop control when the current and voltage are adjusted simultaneously in the current coil and the coil voltage, automatically with a minimum error measure and remember the first voltage and the current at which the actuation of the apparatus without stopping the process of changing the current and voltage, and then measure and memorize the voltage and current release of the contacts of the device.
Thus, in the General case at the end of the test cycle on the indicators shows the current and voltage actuation of the contacts, as well as current and voltage release contacts.
This is achieved due to the fact that the control unit contains a shaper circuit OR two circuits And the first and second triggers, inverter, first and second switches, the first pole of the first switch is connected to the first output unit, and the first pole of the second winding of relay contacts is, otorongo is connected to the second output unit, the second pole of the switch is connected to the first output driver, the input connected to the start button, and the second output with the first input of the first circuit And the input of the inverter, the output of which is connected to the first input of the second circuit And second input circuits And connected to the circuit output OR inputs which are connected to first and second inputs of the block, the outputs of the first and second circuits connected respectively to the inputs of the installation in the “1” of the first and second triggers, inputs reset flip-flops connected to the “reset”button, the outputs of triggers connected with the third and the fourth outputs of the block.
Figure 1 presents the block diagram of the proposed device, figure 2 - block diagram of the control unit, figure 3, 4 shows the signals in a time-dependent characteristic points of the device.
Below is described as an example implementation of a device for controlling devices of the trolley, such as relay current REV-571, relay minimum current REV-830, automatic switch AV-8A-1, voltage relay REV-827, relays acceleration P-B-3, which are described in the book Vesnik GV Trolleybus passenger ZIU 682B, M., Transport, 1977, p.118-122, 139, 199.
The device (1) contains the unit 1 power supply (PSU), which by means of the switch B1 is connected to 3-phase industrial mains supply.
In BP there is a source of constant voltage VPpower e the trip elements of the entire device, and powerful step-down transformer connected to output output 1 BP. Output 1 is connected to the input high-current block 2, containing 3-phase full-wave rectifier 3 with a relatively small output voltage, for example 5, but is designed for high current, for example up to 1000 A.
Outputs 41, 42the rectifier is loaded on the chain containing connected in series key 5, the inductor 6, the shunt 7, the current coil 8 of the controlled apparatus 9. Between the common point of the key 5 and the inductor 6 and 42switch 10.
To exit 2 PSU connected to the power input of the high voltage unit 11 containing the controller 12 AC voltage, the output of which is connected to the block 13 containing a rectifier and a filter.
As the block 12 may be used by the regulator, allowing the team to smoothly increase the AC voltage and then decrease (similar to the controller described in A.S. No. 741389, M CL H 02 M 5/12).
To the output unit 11 is connected to the winding 14 of the audited unit 15, which has the contacts 16 (normally open and normally closed). Such contacts 17 and has audited current device 9.
There is a block of 18 management (BU), which contains (1, 2) shaper 19, the inverter 20, the circuit of the first 21 and second 22 And the first 23 and second 24 switches, relay K24, the circuit 25 OR the first 26 and second 27 triggers, the outputs of which soy is inany respectively to the outputs of the “o 3”, “o 4” BOO.
The first input circuit 21 And is connected with the second output driver 19 and the input of the inverter 20, the output of which is connected to the first input circuit 22 I.
The second input circuits connected to the output of the circuit 25 OR its inputs connected to the inputs I 1 and I 2 BU. The first output driver is connected with the first poles of the switches 23, 24, the second pole of which is connected respectively with the output “o 1” BU and the relay coil 24K. The input of the shaper 19 is connected to the button 28 “start”. The outputs of the circuits 21, 22 And connected with the installation inputs respectively of the first 26 and second 27 triggers, the outputs of which are connected respectively to the outputs of the “o 3, o 4” BU. Inputs reset flip-flops 26, 27 are connected with the button 29 “reset”. The relay contacts 24K connected to the output “o 2” BOO.
As part of the device there is a measure of the current 30 and voltage 31, each of them contains two channels: channel measuring and memorizing the current (voltage) operation and channel measuring and memorizing the current (voltage) release devices. Each channel contains respectively schema 32, 33, 34, 35 sample-hold (similar to the scheme described in the book Lffacename. “Operational amplifiers and linear IC's”. M. MIR, 1995, str-241), analog-to-digital converters (ADC) 36, 37, 38, 39, indicators 40, 41, 42, 43. The information inputs of the circuits 34, 35 meter neprezentabelen with the output of block 11, and the information inputs of the circuits 32, 33 current meter connected in parallel with the shunt 7. Control inputs of the circuits 35, 33, designed to measure and record the voltage and current operation, are interconnected and the output “o 3” BOO, control inputs of the circuits 34, 32, intended for storing the voltage and current release, interconnected, and the output “o 4” BU. The outputs of the circuits 32, 33, 34, 35 are connected with the inputs of the ADC 36, 37, 38, 39, respectively, and the outputs of the latter are connected respectively to the inputs of the indicators 40, 41, 42, 43.
Control input key 5 is connected to the output of pulse-width modulator (PWM) 44 and the input of the inverter 45, and the control input key 10 with the output of the inverter 45, the input start PWM is connected to the output of the clock generator 46, and the modulating input - the output of summing amplifier 47, the first input connected to the output impedance of the amplifier 48, the amplifier input is connected to output 4irectifier 3 through a decoupling element such as a capacitor 49. The second input of the amplifier 47 is connected to the output of the standby generator 50, the control input of which is connected to the output “o 2” BOO.
Before the start of the control, if the apparatus - voltage relay, the winding 14 is connected to terminals 511, 512designed for constant flow slowly changing the voltage, and output the one of the contacts 16 - to input “I 1” BOO.
If the controlled apparatus - current relay 9, the winding 8 (its resistance substantially less than 1 Ohm) across the power terminals 521, 522include in the source circuit high current to the elements 3, 5, 6, 7, 10, and conclusions one of the contacts 17 - to the entrance of “I 2” BOO.
Then in BU 18 closes the switch 23 associated with the current unit 2, if the controlled apparatus - current relay, or the switch 24, if the controlled device is a voltage relay, or both, if the controlled device is a relay with two windings: current and voltage. In the latter case, the winding current of the device is connected to terminals 521, 522the winding voltage to terminals 511, 512and the relay contact is connected to input 1 or 2 BU.
Consider first the case of monitoring current relay. Close the switch 23. When the relay is connected to the device include the switch B1. After some time, necessary for the completion of transient processes in the elements of the device, press the button 29 “reset”. Output triggers 26, 27 are set to low voltage levels, which corresponds to the establishment of schemes 32...35 sample-hold in the state of tracking the input signal for informational inputs. Then press the button 28 “start” (figure 2, 3). Shaper 19 on the leading edge of a start signal produces them is the pulse duration t and.
tnthe rise time of current on the outputs 521, 522(or voltage rise at the outputs 511, 512);
tin- exposure time controlled apparatus under maximum current (voltage).
Time tnas twiththe fall time of the current (voltage) from the maximum to 0, selected from considerations of acceptable values of the test time and component of error due to inertia ratio of scanned devices, delays in meters and rate of rise (fall) test current (voltage). Almost to the above-mentioned apparatus of the trolley is acceptable tn≈twith≈ 20 sec.
For tnthe generator 50 generates the rising edge, which goes to the “input 2” summing amplifier 47, the input 1 of the amplifier receives the signal from the output of the amplifier 48. This signal “o 48” is an inverted variable component (ripple as 6-th harmonic for 3-phase 2-half-cycle rectifier with respect to the network) of the current output of the rectifier. The output of the amplifier 47, as by modulating the PWM input 44, a signal “o 47” represents the sum of signals output 50” and “o 48”, and at the input of the start pulse from the output of the generator 46 are of the type “o 46”, moreover, the frequency several times, for example 6 times, as shown in figure 4, is greater than the frequency of the pulsations. The ripple amplitude for 3-phase full-wave rectifier (Fig 3, 41-42) is approximately 10%, as well as their period is one order of magnitude over time of actuation (release) of the controlled apparatus, make a ripple error in the determination of the current (voltage) operation.
In the proposed device for modulating the PWM input 44 receives the signal “o 47”, (Fig 4), pre-modulated amplifier 47 ripple in antiphase.
Consider the process on the site period TPpulsation. To simplify the reasoning in the diagram) figure 4 intervals of sinusoids presented in the form of a triangular signal. The sawtooth voltage UNRis the internal signal element 44 PWM, which is produced by the internal oscillator with period T3triggered by the leading edge of pulses “o 46”. This signal (UNRcompared to the PWM signal “o 47, in each period T3formed on the PWM output 44 pulses with variable duration of tR1...tsthat include (figure 4 shaded bars) and off key 5. When turning on the key current i8flows through the circuit: o 41the key 5, the inductor 6, the shunt 7, terminal 521the winding apparatus 8 9 terminal 52 , o 42. When this energy is stored in the inductor 6 and the winding 8. When you turn off the key 5 (where there's no shading intervals between tWsignal from the inverter 45 includes a key 10 and in these intervals the current source are the throttle and winding, current flows in the same direction through the circuit: inductor 6, the shunt 7, terminal 521the winding 8, the terminal 522the key 10, the orifice 6. When this current has only a pulsation with a period of T3that amplitude is several times smaller pulsations with a period of Tpat this period it significantly less time actuation (release) system, that reduces the measurement error of the current operation (release) apparatus. For comparison on FIGU shows the current ilfor the case of application of PWM without additional modulation. The magnitude of the current ilproportional to the sites, limited from above by the line “o 41-42” the output voltage of the rectifier 3, the bottom x-axis, left side lines trailing (falling) of the front of the sawtooth voltage UNR,and on the right, the vertical lines drawn through the point of intersection of the linearly increasing voltage UNRvoltage “o 50”, which would have occurred at the output of amplifier 47, if there was no signal I 1 amplifier 47, i.e. for the case of using PWM to control the current known the circuit without mixing signal “o 48” (figure 3). Current contains pulsations with a period of T3and with a period of T6.
Current i8increases starting from 0. When the current value of i8=Icfwhere Icf- current tripping the overcurrent relay 9, one of the contacts 17 is excited by the signal “I 2” BU, who through the circuit 25 is supplied to the inputs of 2 schemes And1And2. Inlet And121 is an enable signal “o 2” shaper 19. The output of the circuit is formed by a setting signal to “1” trigger 26, the output “o 3” BOO when this occurs, a setting signal circuits sample-and-hold 33, 35 in storage. They go into this state. Scheme 33 memorizes the current Icpthe signal proportional to whom was the information input. This value is converted to ADC 37 into digital form and displayed by the indicator 41. Circuit 35 stores the voltage, which in this case is 0, and displays via ADC 39 on the display 43.
Current i8continues to grow to the maximum value for tnwhen this is displayed on the second channel elements 32, 36, 40, followed by exposure tinand at the end of the interval tandcurrent monotonically starts to fall. At some point it reaches a value of lOTP- current release relay, relay 9 releases, one of the contacts 17 again excites the signal “I 2” BOO, across the scheme OR 25 goes on “I 2” schemes And 21, 22, but now an enable signal is present at the output of the inverter 20 and the input 1 And 22, is set to “1” trigger 27, “output 4” BOO, you receive the setting signal circuits 32, 34 in storage. Scheme 32 memorizes the current IOTPthrough ADC 36 displays on the display 40. Scheme 34 stores a voltage that is equal to 0, and displays via ADC 38 on the display 42. The cycle is completed. The indicator displays current Icpand IOTP. Observe the results. If necessary, the cycle is repeated. After this unlock switch B1.
Before the control apparatus with the coil voltage (switch 23 is turned off) include the switch 24, to the terminals 511, 512connect the winding 14 of the apparatus 15, one of the output contacts 16 is connected to “I 1” BU. Include the switch B1. Press the “reset”button, then “start”output BP to the input device 12 is supplied with alternating voltage, BU the signal “o 19 (1, 2), which is supplied through the switch 24 to the relay K24, the relay is actuated and its contacts through the “o 2” BU 18 in the controller 12 starts the mode of fading AC voltage.
For tnat the output of the controller 12 increases the AC voltage “o 12”, Fig 3, which is fed to the rectifier 13 to the filter and the voltage “o 13” is supplied to terminals 511, 512check reuleaux is 15, the winding 14 and to the information inputs of the circuits 34, 35 of the block 31 of the measurement. By analogy with the operation mode control current relay remembered voltage Ucpoperation of the relay circuit 35 through 39 ADC is displayed by the indicator 43. After a time tandrelay K24 releases and their contacts in the controller 12 starts the mode of the voltage dip. The voltage on the coil 14 decreases, reaches the value UOTPreleasing, relay 15 releases, contacts 16 affects “I 1” BU 18, through the scheme, OR 25, AND 22 is set to “1” trigger 27 and “o 4” block 18 team “storage” arrives at the inputs of the control circuits 34, 32. Scheme 34 memorizes the voltage UOTPrelay 15. UOTPdisplayed through the ADC 38 indicator 42.
When the control apparatus having a winding current and voltage, pre-close both switches 23 and 24, with the current coil is connected to terminals 521, 522the winding voltage to terminals 511, 512and the output contacts to the “Ref 1” or “Ref 2” BOO.
For the coil current and coil voltage processes control flow as described above, and at the end of cycle indicators display the current Icpin the current coil, the voltage Ucpthat took place on the winding voltage, and IOTPand UOTP. After the end of the control switch B1 RA is michaut the food chain.
1. Device for controlling devices tram and trolley-bus, containing the power supply with the switch connected at the first output with a power input high current unit comprising a rectifier connected in series inductor and shunt, the first output current of the unit connected to the current coil of the audited unit, the shunt is connected to the second output unit connected to the information input of the measuring current and the second output of the power supply connected to the power input of the high voltage unit, the output of which is connected with the information input measuring voltage and with winding voltage check of the device, additionally, there are controls that make up the control unit, the first and second the outputs of which are connected to control inputs, respectively, of high-voltage and high-current units, and the first and second inputs connected to the terminals of the contacts of the tested apparatus, characterized in that in the current block, the outputs of the rectifier is loaded on the circuit containing the serially connected first key, the throttle, the shunt and the current coil of the audited unit, and between the common point of the inductor and the first key and the common output of the rectifier connected to the second key, the control input of the first key is connected to the output of pulse-width modulator (PWM) and the input of the inverter, and control of the Commissioner, the input of the second key is connected to the output of the inverter, while modulating the PWM input connected to the output of summing amplifier, a first input which corresponds to the amplifier and decoupling element connected to the rectifier output and the second input of the summing amplifier connected to the output of the standby generator, whose input is connected with the control input of the current block and the input of the start PWM is connected to the output of the clock generator, in addition, a measure of the current and voltage have the first and second channels each, with each channel input is enabled schema of the sample-hold informational inputs which are connected to information inputs of the meter, and the control inputs of circuits sample-and-hold in the first channel both meters are connected to the first control inputs of the meter, and the second channel with the second control inputs of the probes, the first control inputs of the meter are connected among themselves and with the third output of the control unit and the second control inputs of the meter are also connected among themselves and with the fourth output of the control unit, in each channel, the output of the circuit of the sample-hold through analog-to-digital Converter is connected with the corresponding indicator, the device supply input connected to the output of the power supply.
2. The device according to claim 1, characterized in that the control unit contains FD is miraval, the first and the second schema And the schema OR the first and second triggers, the inverter and the first and second switches, relays, buttons "start" and "Reset", and the first pole of the first switch is connected to the first output unit, and the first pole of the second winding of the relay, the contacts of which are connected with the second output unit, and the second pole of the switch is connected to the first output driver, the input connected to the start button, and the second output with the first input of the first circuit And the input of the inverter, the output of which is connected to the first input of the second circuit And second input circuits And connected to the circuit output OR inputs which are connected to first and second inputs of the block, and outputs the first and second circuits And connected to the set inputs of the first and second triggers, respectively, the outputs of which are connected respectively with the third and fourth outputs of the block, and the reset inputs of the triggers are combined and connected to the "Reset"button.
FIELD: measuring and monitoring technique, possibly monitoring of different objects.
SUBSTANCE: system includes control unit, unit for calling testing programs, coupling unit, measuring unit, test stimulation unit, power sources, unit for distributing signals, memory unit, N matching units, N testing program units. Each testing-program unit has evaluation circuit and two memory devices.
EFFECT: lowered volume of equipment, simplified organization of monitoring process and development of software.
FIELD: automatic control, applicable in systems with excessive quality of transducers, for example, accelerometers, a failure of one of which should not result in a failure of the control system.
SUBSTANCE: the method is based on a periodic check-up of relation between the measured parameters of motion characterizing the correct operation of the transducers, fixation of the moment of failure of the relation, comparison of the readings of the transducers at this moment and at the moment preceding the moment of disturbance of the relation, and determination of the failed transducer by the results of the comparison.
EFFECT: expanded functional potentialities due to possibility of determination of the failed transducer in any excess system.