RU2454336C1 - Electric locomotive microprocessor-based control system - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to railway transport and aims at perfecting ACS to be used at AC electric rolling stock. Proposed system is designed to be mounted at new electric locomotives and currently operated trains equipped with rectifier-inverter converters with four-range voltage control to allow operation at higher load currents and notable distortions in contact system voltage shape. Microprocessor control system uses one microcontroller exercise manual and automatic control by two parameters: current and speed. Note here that portion of data from transducers is processed before microcontroller to expand diagnostical functions of the system with data display on indication unit. In case protective hardware operates recommendations are displayed to allow engineman to decrease time of detection and recovery of electric locomotive serviceability.

EFFECT: higher efficiency and reliability.

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Description

The proposed system allows for two-level regulation. The first level is manual control of the parameters of the electric locomotive, the second is auto-regulation according to two parameters: armature current and speed in both traction and regenerative braking modes.

Known devices that can operate in two-level regulation. This is the control unit of the rectifier-inverter converter BUVIP-133 together with the automatic control unit BAU-002 on the electric locomotive VL85 [1]. The use of analog elements and the simplest integrated circuits made it possible to implement a rather “hard” mode of operation of the system in this electric locomotive both in traction mode and in regenerative braking mode at both levels of regulation.

The use of microprocessors and integrated circuits of medium degree of integration in a microprocessor-based diagnostic control system (ICS) [2, 3] increased the flexibility of the control system, but required for each input signal to establish matching elements that convert analog, discrete, pulse signals to digital form, which significantly affected on the dimensions and cost of the system.

The use of microcontrollers and integrated circuits of a large degree of integration in the microprocessor-based diagnostic management system (MUDN) [4, 5] made it possible to reduce the size and cost, however, the noise immunity of the system decreased and the number of failures increased.

The closest the claimed device in technical essence is the microprocessor control unit of the rectifier-inverter converter BUVIP (M) [6], which is adopted as a prototype.

The disadvantage of the prototype is the complete exclusion from the tracking channels of the voltage shape of the contact network, especially at high loads of analog circuits and the absence of a second level of regulation - auto-control, which does not allow to implement effective methods of controlling an electric locomotive.

In the proposed device, these disadvantages are eliminated due to the fact that in the synchronization channel, where the clock pulses are generated, on the analog microcircuits, preliminary processing of the actual form of the synchronization voltage is performed using phase correction of the clock pulse. Due to the strong distortion of the voltage shape of the contact network at high loads, the synchronization voltage can go several times through the zero position. Moreover, the absence of a special circuit can lead to the formation of several clock pulses and a malfunction of the control system. Conventional hardware currently generates only one clock pulse, even with several transitions of the synchronization voltage through zero. The hardware-implemented phase delay allows you to create a “floating” clock with an inertia close to the inertia of the traction motors, which eliminates the fluctuation of the currents of the anchors of the traction motors.

To form the minimum permissible thyristor opening phase according to potential conditions, a comparator is used, at the first input of which an output signal of the OR circuit _min is supplied, which emits the minimum amplitude of the rectified voltage from the sensors. Sensors monitor the voltage supplied to the inputs of the VIP. A reference voltage is applied to the second input of the comparator.

Due to the distortion of the voltage shape, the response time of the comparator changes from the beginning of the half-wave. On the front of the comparator, the microprocessor forms the initial opening angle of the thyristors in accordance with the algorithm. In the traction mode, the duration of the first switching is allocated in the form of the tracking voltage, the microcontroller generates a pulse delayed during the switching time and is fed by the algorithm to the corresponding VIP arms. After the passage of the delayed pulse from the tracking voltage, the second switching is allocated, and at the end of it a pulse is formed about the completion of the processes at the beginning of the half-wave of the rectified voltage. All these signals are generated in hardware, and their presence is “hard-checked”. At the same time, the microcontroller is freed from this standard operation, a part of the program is reduced, and the volume for the second-level control program is increased.

At the first level, in the traction and regenerative braking mode, the microcontroller generates only adjustable pulses depending on the control voltage set by the driver and issues them through the amplifiers to the VIPs in accordance with the algorithm.

At the second level of regulation, all signal processing schemes of the first level are used. The voltage regulator of the VIP control becomes the current setter of the traction motors, and the voltage regulator of the control of the VUV-speed setter. The given signals are sent to the microcontroller, but are perceived by another program, a two-loop closed circuit of auto-regulation according to two parameters is assembled. The signals about the actual currents of the anchors and speed are fed through the feedback circuits after preliminary processing to the microcontroller. In accordance with the task, the microcontroller selects the control zone and maintains the speed set by the driver both in traction mode and in recovery mode.

The implementation of the proposal is shown in a specific example, where a simplified diagram of one section of an alternating current electric locomotive with two VIPs, one VVV and a microprocessor control system is given.

Figure 1 shows: current collector 1; main switch 2; primary 3, secondary 4, 5 windings of the power transformer and auxiliary winding 6. The synchronization voltage U _si1 , U _si2 , U _f is removed from the sensors 7, 8, 9. The tracking voltage U _s1 , U _sl2 comes from the sensors 10, 11. V in the recovery mode, signals about the duration of the switching angles U _γ1 -U _γ4 are formed by sensors 12-15. The rectified voltage U _dVIP is supplied to each pair of motors 24, 25 from the VIP 16, 17. The excitation windings are supplied from the VVV 18. The magnitude of the currents of the anchors of the traction motors is monitored by current sensors 19, 20, and speeds of 22, 23.

Changing the mode of traction for recovery is carried out by contactors of the brake switches 26, 27. Diode-resistor circuits 28, 29 provide stability to the recovery mode and protection against circular current. The magnitude of the excitation of the traction motors is determined by the excitation windings 30, 31. The specified signals to the control system are received from the controller of the driver 32 in both the first and second modes.

The device for microprocessor control of an electric locomotive contains a microprocessor kit with four groups of inputs and three groups of outputs, the first group of inputs of the microcontroller connected via a signal _conditioning unit 33 with three synchronization voltage sensors U _si1 , U _si2 , U _f and two sensors for monitoring the network voltage shape U _sl1 , U _sl2 ; with four current sensors I _i1 -I _i4 and four speed sensors n1-n4; the power supply unit 37 of the control system elements is connected to a power source of the electric locomotive control circuits; the first group of outputs is connected through amplifiers to coils of contactors, relays, etc .; the second group of outputs through the output amplifiers 39, connected to the control electrodes of the power thyristors in blocks 16, 17, 18; the third group of outputs is connected via an RS485 interface to the display unit 40. Unlike the prototype, the first block 33 contains analog microcircuits for preliminary processing of information received at the input of the microcontroller, while, due to the reduction in the volume of the program, the second and third input blocks (34 and 35, respectively) for auto-regulation according to two parameters: armature current and speed, the second block 34 being connected to the current and speed controllers and the armature current sensors, and the third block 35 to the control points for diagnosis with standing equipment; output unit 36 for controlling devices; display unit 40 to reflect operational, emergency and reference information.

On the main panel of display unit 40, two virtual devices with two arrows are displayed to indicate: on the first device the set and actual armature current, and on the second device - the set and actual speed. At the top of the screen, special signs reflect the status of the main protection devices. If any protections are triggered, the corresponding signal is illuminated, and a prompt is given on the screen to the driver about measures to restore the operability of the electric locomotive.

On other panels of the display unit, the currents of each engine, their speed, the status of devices and relays, the parameters of the control angles both in traction mode and in regenerative braking mode are reflected on virtual instruments.

To increase reliability, all units of the microprocessor system have redundant ones, and they are powered separately from unit 37. Switching of the units occurs automatically in the event that individual signals do not meet the permissible values.

Thus, the transfer of processing part of the information to a hardware basis made it possible to unload the microcontroller, organize the second level of regulation, and significantly reduce the size of the system. For example, in comparison with the MCHS, [2, 3] almost 3 times, compared with the MCHS, [4, 5] 2 times.

The proposed control system was made in a mock version, then a prototype was made, which was tested at the stand and in experimental trips on an electric locomotive. After manufacturing the second prototype, the electric locomotive went through trial operation. After the preparation of technical documentation, the management system was presented to the interdepartmental commission, where after discussion a recommendation was received for the release of an experimental batch.

Information sources

1. Electric locomotive VL85. Operation manual / B.A. Tushkanov, N.G. Pushkarev, L.A. Pozdnatova, etc. M .: Transport, 1992. - 480 p.

2. Electric locomotive EP1. Operation manual in 2 volumes. - Novocherkassk: LLC “PK” “NEVZ”, 2008, - T.1. - 528 s.

3. Electric locomotive EP1. Operation manual in 2 volumes. - Novocherkassk: LLC “PK” “NEVZ”, 2008, - T.2. - 576 p.

4. Electric locomotive main 2ES5K. Operation manual in 2 volumes. - Novocherkassk: LLC “PK” “NEVZ”, 2008, - T.1. - 635 s.

5. Electric locomotive 2ES5K. Operation manual in 2 volumes. - Novocherkassk: LLC “PK” “NEVZ”, 2008, - T.2. - 640 s.

6. Patent No. 2251785, Russian Federation, IPC Н02M 1/084. The microprocessor control unit of the rectifier-inverter converter BUVIP (M) / Rabinovich M.D., Sorin L.N., Krivnoy A.M., Kromskov S.A., Plis V.I., Stekolshchikov D.V., Chekmarev A .E .; Applicant and patent holder of CJSC “Industry Center for the Implementation of New Equipment and Technology”. - application 2002128124/09; declared 10/22/02; publ. 05/10/05. Bull. No. 2. - 2 p.: Ill.

Claims (1)

A microprocessor control device for an electric locomotive, comprising a microprocessor kit with four groups of inputs and three groups of outputs, the first group of inputs of the microcontroller connected via a signal conditioning unit with three synchronization voltage sensors and two sensors for monitoring the network voltage shape, with four current sensors and four speed sensors; the power supply of control system elements is connected to a power source of the control circuit of an electric locomotive; the first group of outputs is connected through amplifiers to coils of contactors, relays, the second group of outputs through output amplifiers is connected to control electrodes of power thyristors; the third group of outputs is connected via an RS485 interface to a display unit, characterized in that the first block contains analog microcircuits for pre-processing the information received at the input of the microcontroller, and due to the reduction in the program volume, the second and third input blocks are introduced for auto-regulation according to two parameters: current anchors and speeds, and the second is connected to current and speed controllers and anchor current sensors, and the third to control points for diagnosing equipment status; an output unit for controlling devices and an indication unit for reflecting operational, emergency and reference information.

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