RU2346829C1 - Method of diagnosing branches of reversible converter of loaded alternating current locomotive - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: proposed method is based on use of two control algorithms of reversible converters of a loaded electric locomotive, which allow for diagnosing the loaded electric locomotive without moving out of the first control zone of voltage across traction electric motors at the parking place.

EFFECT: possibility of diagnosing all branches of a reversible converter at the parking place, possibility of identifying a faulty branch of a reversible converter and reduced labour input of detecting faults.

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Description

The invention is applied to railway transport and relates to a method that allows, without leaving the first zone of voltage regulation on traction electric motors in a parking lot, to diagnose all the arms of a rectifier-inverter converter (VIP) of an electric locomotive under a contact wire.

VIP is designed to rectify a single-phase alternating current with a frequency of 50 Hz into a constant, continuously regulating the supply voltage of traction motors in traction mode and converting direct current into a single-phase alternating current with a frequency of 50 Hz and smoothly regulating the counter-EMF of the inverter in the mode of regenerative braking [1]. Several VIPs are used on an electric locomotive, depending on its series.

Figure 1 presents a simplified schematic diagram of an electric locomotive. The circuit diagram contains a traction transformer having a primary (U ₁ ) and a secondary winding made in the form of three series-connected sections, two of which are of equal voltage (a1-1 and 1-2), and the third is of double voltage (2-x1 ), and four parallel branches of VIP, parallel connected between the DC bus (Fig.1). Each branch of the VIP contains a pair of serially connected controlled arms of the thyristors, and their midpoints are connected to the corresponding terminals of the secondary winding of the transformer. The power part of the VIP, shown in figure 1, consists of eight thyristor arms V1, V2, V3, V4, V5, V6, V7, V8. To the positive and negative buses, the VIPs are connected through a smoothing reactor (3), parallel-connected traction motors of an electric locomotive containing an armature (D1, D2, Dn) and field windings (OBI, OB2, OBn), Fig. 1.

There is a known method of operation of the VIP control, consisting of four zones of regulation of the rectified voltage on the traction motors, in order to control the speed of the electric locomotive by supplying control pulses (α ₀ is the minimum opening angle of the thyristors, α _p is the angle of phase control) on certain shoulders of the VIP control unit rectifier-inverter converters (BUVIP) or microprocessor-based motion control and diagnostics system (MASD), table 1 [1].

The method includes four voltage control zones (figure 1):

The first zone: control pulses are fed to the shoulders of the VIP V3, V4 and V5, V6, connected to the section 1-2 of the secondary winding of the transformer, - form the first zone of voltage regulation;

The second zone: control pulses are fed to the shoulders of the VIP V1, V2, V3, V4 and V5, V6 connected to the secondary winding section A1-2, - form the second voltage control zone;

Third zone: control pulses are fed to the shoulders of the VIP V3, V4, V5, V6 and V7, V8 connected to the transformer secondary section 1-x1, - form the third voltage regulation zone;

Fourth zone: control pulses are fed to the shoulders of the VIP V1, V2, V3, V4 and V7, V8 connected to the transformer secondary section a1-x1, - form the fourth voltage control zone.

Currently, a method for diagnosing the operability of an electric locomotive after repair in a parking lot is a control algorithm that is used only in the first regulation zone, shown in Table 1. The serviceability of the arms of the VIP of an electric locomotive, electronic and electrical equipment is controlled by the appearance of currents from the armature of the traction motors when applying control pulses to the shoulders of the VIP V3 , V4 and V5, V6 (first zone), the current is observed by the ammeter located in the driver’s cab of the electric locomotive, or by the monitor of the microprocessor control system and diagnostics the notes. The opening angle of the VIP thyristors is made by turning the control wheel of the controller to position P (preparation, collection of the traction scheme) and then from the HP position (beginning of regulation) smoothly turning in the direction of the end position of the first zone [1]. The driver sets the current value required to check the VIP and electronic equipment channels.

The functional purpose of the VIP, its design and principle of operation, determine the special requirements for its repair in a locomotive depot and the verification of its operability after repair under load.

The disadvantages of a typical VIP control method are the inability to diagnose all the shoulders of a VIP electric locomotive parked under load. This is especially necessary after the repair of AC electric locomotives in the locomotive depots according to the cycle of all current repairs (TR), maintenance (MA), medium and major repairs, since after that the electric and electronic equipment of the electric locomotive under the contact wire is diagnosed at operating currents of the load and transfer of the electric locomotive into operation. However, the repair team has the ability to check the operability of the VIP arms in a parking lot under load with only four arms (first zone), V3, V4, V5, and V6 (without leaving the first voltage regulation zone), instead of eight of them due to the formation of high currents of traction motors , since in the parking lot of the electric locomotive the counter-EMF of the traction engines are equal to zero and the active resistance is small. An attempt to enter the second regulation zone leads to the movement of the electric locomotive and the emergency mode of the traction motors due to the occurrence of high currents, which causes a trip that protects the traction scheme of the electric locomotive. Consequently, half of the electrical and electronic parts of the equipment, which operates under the control of the respective shoulders of the VIP, remains untested. It is also impossible to determine the malfunction of the VIP arm with an accuracy of one, which significantly increases the complexity in determining the malfunction that occurs, which in operation leads to the failure of the electrical equipment of the electric locomotive.

As a result, when applying the standard method of checking the shoulders of the VIP of an electric locomotive, a “technological hole” was formed, which allowed issuing electric locomotives after repair was put into operation, while not guaranteeing its serviceability in the entire voltage control range, i.e. in zones 2, 3 and 4 (table 1).

The aim of the invention is:

- improving the safety of train traffic;

- without leaving the first zone of voltage regulation on traction electric motors in the parking lot, to diagnose the electrical and electronic equipment of all the arms of the rectifier-inverter converters of the electric locomotive under the contact wire;

- to within one, determine the faulty arm of the VIP;

- reducing the complexity of determining the failure of an electric locomotive.

The proposed method consists in the fact that the control signals of the first regulation zone are fed to the VIP according to the new control algorithm in order to check all the shoulders of the VIP in the parking lot under load. It is proposed to use two versions of the VIP control algorithm: four-arm and two-arm.

,

и т.д. до

, подходящие соответственно к первому, второму и т.д. и восьмому плечам ВИП. При установке первого переключателя в положение 5' производится переключение устройства во второй вариант диагностики по двухплечевому варианту. В таблице 3 показан алгоритм второго варианта работы устройства, представленного на фиг.2.The first option is that control signals are applied to the four arms of the VIP, and all kinds of two-half-wave bridge rectification schemes consisting of four arms of the VIP can be used, forming a single-phase bridge circuit of N-bridges. Table 2 shows the algorithm of the first embodiment of the device shown in figure 2. Figure 2 shows one embodiment of the device. Switching of the checked shoulders is carried out by two dial switches, the moving contact of which is shown by a rectangle, where 1 ', 2', etc. up to 5 'and 1'',2'', etc. up to 8 '' are the numbers of the fixed contact of the switch, where C3, C4, C5, C6 are the output control signals of the BUVIP, MSUD supplied to the third, fourth, fifth and sixth arm of the VIP in the first zone. Figure 2 shows the wires

,

etc. before

suitable respectively to the first, second, etc. and the eighth shoulders of the VIP. When the first switch is set to 5 ', the device is switched to the second diagnostic option using the two-arm option. Table 3 shows the algorithm of the second embodiment of the device shown in figure 2.

The second option is that the control signals are fed to the two arms of the VIP, and all sorts of options for a half-wave rectification scheme consisting of two arms of the VIP, working only at a positive half-voltage with respect to the connected arms of the VIP, can be used.

Thus, the diagnostics of the performance of all the shoulders of the VIP of the electric locomotive, electrical and electronic equipment of the electric locomotive.

The supply of control signals from BUVIP, MSSD to the pulse formation system (SFI) is carried out by applying a switch (figure 2).

Diagnostics according to the first option is necessary to create large currents of traction motors; at such currents, the performance of the shoulders of the VIP of an electric locomotive and its control circuits is more qualitatively checked.

The serviceability of the shoulders of the VIP of an electric locomotive, electronic and electrical equipment is controlled by the appearance of currents of the anchors of the traction motors, when control pulses are applied to the corresponding shoulders (table 2, 3), the current is monitored by an ammeter located in the driver’s cab of the electric locomotive, or by the ICMD monitor.

The lack of armature current signals a malfunction of the VIP arm.

Its exact determination is made according to the two-arm version as follows: for example, when forming control pulses on two arms, V5 and V2, the VIPs observe that the currents of the traction motor anchors are zero, therefore, the V5 or V2 arm is faulty on the VIPs. To accurately determine the faulty shoulder and its control circuits, it is necessary to check the options containing the shoulders V5, V2, in combination with other VIP arms; for example, V5, V4 - by applying control pulses to them, thus checking whether there is a load on the traction motors. If, in combination with other shoulders, the V5 shoulder works and there is a load on the engines, then the VIP arm V2 is faulty.

The proposed algorithm for diagnosing the shoulders of a VIP electric locomotive under load in the first voltage control zone, in the parking lot, can also be implemented in regenerative braking mode.

Information sources

1. Electric locomotive VL85. Operation manual [text] / B.A. Tushkanov, N.G. Pushkarev, L.A. Pozdnyakova et al. - M .: Transport, 1995. - 480 pp., Ill., Tab.

Table 1 Zone Half period VIP shoulders V1 V2 V3 V4 V5 V6 V7 V8 one ← α ₀ α _p → α _p α ₀ , α _p 2 ← α _p α ₀₃ α ₀ → α _p α ₀₃ α ₀ 3 ← α _p α ₀₃ α ₀ → α _p α ₀₃ α ₀ four ← α _p α ₀₃ → α _p α ₀₃ α ₀ α ₀

table 2 Zone Half period VIP shoulders V1 V2 V3 V4 V5 V6 V7 V8 one ← α ₀ α _p → α _p α ₀ ← α _p α ₀ → α _p α ₀ ← α _p α ₀ → α _p α ₀ ← α _p α ₀ → α _p α ₀

Table 3 Zone Half period VIP shoulders V1 V2 V3 V4 V5 V6 V7 V8 one → α _p α _p ← → α _p α _p ← → α _p α _p ← → α _p α _p ← → ← α _p α _p → ← α _p α _p → ← α _p α _p → ← α _p α _p

Claims (1)

A method for diagnosing the shoulders of rectifier-inverter inverters of an AC electric locomotive under load, comprising supplying control pulses to the shoulders of rectifier-inverter converters V3, V4 and V5, V6 connected to the second section of the transformer secondary winding section 1-2, characterized in that in the first zone the control signals are supplied according to the first four-arm variant with the possibility of connecting various variants of half-wave bridge rectification circuits consisting of four treat the rectifier-inverter converter, forming a single-phase bridge circuit of N-bridges, and then the control signals are supplied according to the second two-arm variant of the half-wave rectification circuit, consisting of two arms of the rectifier-inverter converter, operating only at a positive half-voltage with respect to the connected arms of the rectifier -inverter converter via switch.

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