Improved traction excitation circuit for direct current-driven internal combustion locomotive

Abstract

Disclosed is an improved traction excitation circuit for a direct current-driven internal combustion locomotive. In the present invention, a typical traction excitation circuit for an internal combustion locomotive is additionally provided with devices such as a circuit breaker, a relay group, and a new excitation regulation apparatus, so as to provide a locomotive having a newly added power generation function in addition to the original properties and functions thereof. An excitation control apparatus is newly added to an original switch device. Surplus traction power in a locomotive traction mode is used to supply power to carriages, thereby enabling convenient switching between train traction and traction power supply while eliminating the need to add a head-end power car for supplying power to a train and related operators when the train consists of a large number of carriages, thereby reducing fuel consumption and noise pollution and improving the riding comfort of passengers in the carriage adjacent to the locomotive.

Description

An improved traction excitation circuit for DC drive diesel locomotive Technical Field

[0001] The invention belongs to the field of traction excitation circuit transformation and relates to an improved traction excitation circuit for a DC transmission diesel locomotive. Background Art

[0002] According to the "China Railway Statistical Bulletin 2020", the national railway locomotive ownership is 22,000 units, of which 13,700 are electric locomotives, accounting for 63.0%; 8,000 are diesel locomotives, accounting for 36.9%. Preliminary analysis shows that the ownership of diesel locomotives with AC-DC transmission is no less than 5,000 units.

[0003] The DF4D diesel locomotive is a typical example of a DC-driven diesel locomotive with a relatively large inventory in China. It uses a 16V240ZJD diesel engine with a nominal power of 2425 kW. The principle of its traction excitation circuit is shown in Figure 1. In the figure, CF represents the tachogenerator, L represents the excitation generator, the 2ZL rectifier unit, and the LTQ excitation regulator. The excitation current for the DF4D diesel locomotive's synchronous main engine F is supplied by the traction excitation generator L, while the excitation current for the excitation generator L is supplied by the tachogenerator CF. The tachogenerator's excitation current is supplied by the battery XDC or the starter generator QF. Under normal traction conditions, the traction excitation circuit includes the excitation of the tachogenerator CF and the excitation of the traction excitation generator L. The excitation of the tachogenerator CF is divided into two parts: the oil motor excitation and the excitation regulator excitation.

[0004] Specifically, the excitation circuit of the excitation regulator is as follows: (+) 110V, X5 / 8 → R1cf1 → 1HKg → X7 / 12 → CF(E1-E2) → X7 / 9 → LTQ(14, 15) → LTQ(5) → X8 / 21, (-) 110V. Excitation of the traction excitation generator L: The rotor of the tachometer generator CF is driven by the diesel engine, and its excitation winding is excited by the oil motor resistor Rgt or the excitation regulator LTQ. When the armature circuit excitation generator excitation contactor LLC is closed, the tachometer generator generates electricity and provides excitation current to the excitation winding of the excitation generator L. The circuit of this excitation current is as follows: CF(+) → X7 / 7 → GLFC → 2HKg → 2DZ → LLC → Rwq (or 1ZJ) → R1t → 2HKg → X7 / 5 → L (excitation winding) → X7 / 6 → CF(-). The three-phase AC power generated by the traction excitation generator L is rectified by the three-phase bridge rectifier 2ZL and then provides excitation current to the excitation winding of the synchronous main generator F. The AC power generated by the main generator is converted into DC power by the rectifier and then provided to the six DC traction motors to drive the locomotive.

[0005] From the above content, it can be seen that the current fuselage only has traction and braking functions and is not capable of directly supplying power to the rear passenger car. Large passenger trains need to add a diesel-powered car to power the train, and a special train needs to be equipped with two crew members to operate the generator car. The generator car needs to be equipped with three 300kW generator sets, which consumes a lot of fuel and causes great noise pollution, seriously affecting the riding comfort of passengers at the stop station and on adjacent passenger cars.

[0006] In view of this, the present inventor provides an improved traction excitation circuit for a DC drive diesel locomotive to solve the above technical problems.

[0007] Summary of the Invention

[0008] The object of the present invention is to overcome the shortcomings of the above-mentioned prior art and propose an improved traction excitation circuit for a DC transmission diesel locomotive. By modifying the existing traction excitation circuit, the surplus power of the locomotive in traction mode is used to power the passenger cars, so that the train can not only realize the traction function, but also the power supply function, thereby eliminating the need to add a power generation vehicle and operators to large passenger car formations, thereby reducing fuel consumption and noise pollution, and improving the riding comfort of passengers in adjacent passenger cars; at the same time, the modified excitation circuit can facilitate the locomotive's conversion between traction and traction power supply functions without affecting the performance and functions of the original locomotive.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] The present invention provides an improved traction excitation circuit for a DC transmission diesel locomotive, comprising: an original traction excitation circuit, and additionally provided with a circuit breaker, a relay group, a new excitation regulating device, and a disconnection point of the original traction excitation circuit to obtain the improved traction excitation circuit;

[0011] The relay group includes a first relay, a second relay, a third relay and a fourth relay;

[0012] One end of the first relay is connected to the circuit breaker, and the other end is connected to the disconnection point of the original traction excitation circuit, and the disconnection point of the original traction excitation circuit is connected to the excitation contactor of the first excitation generator in the original traction excitation circuit;

[0013] One end of the second relay is connected to the new excitation regulating device, and the other end is connected to the tachometer generator in the original traction excitation circuit;

[0014] The new excitation regulating device is also connected to the excitation winding of the excitation generator in the original traction excitation circuit;

[0015] One end of the third relay is connected to the excitation winding of the tachometer generator in the original traction excitation circuit, and the other end is connected to the negative pole of the power supply of the excitation regulator in the original traction excitation circuit;

[0016] One end of the fourth relay is connected to the positive electrode of the excitation power supply, and the other end is connected to the positive input terminal of the power supply of the excitation regulator in the original traction excitation circuit.

[0017] Furthermore, the first relay includes an open point and a closed point, the open point and the closed point are respectively arranged on two branches, the branch where the open point is located is connected to the excitation winding of the excitation generator in the original traction excitation circuit, and the branch where the closed point is located is connected to the excitation contactor of the first excitation generator in the original traction excitation circuit, the open point is used to control the connection state of the relay and the improved traction excitation circuit, and the closed point is used to connect the disconnection point of the original traction excitation circuit;

[0018] The second relay, the third relay and the fourth relay have the same structure;

[0019] The second relay is used to control the connection state between the original traction excitation circuit and the new excitation regulation device;

[0020] The third relay is used to control the connection state between the original traction excitation circuit and the excitation regulator of the original traction excitation circuit;

[0021] The fourth relay is used to control the working state of the excitation regulator in the original traction excitation circuit.

[0022] Furthermore, when the original traction excitation circuit is working, the open point of the first relay is disconnected, the closed point of the first relay is closed, the contact of the second relay is disconnected, the contact of the third relay is closed, and the contact of the fourth relay is closed.

[0023] Furthermore, when the improved traction excitation circuit is working, the open point of the first relay is closed, the closed point of the first relay is opened, the contact of the second relay is closed to connect the new excitation regulation device, the contact of the third relay is opened to cut off the excitation regulator in the original traction excitation circuit, and the contact of the fourth relay is opened to cut off the working power supply of the excitation regulator in the original traction excitation circuit.

[0024] Furthermore, the improved traction excitation circuit also includes an operating condition selection circuit, which includes a first operating condition selection switch, a second operating condition selection switch and a traction excitation circuit switching relay. The first operating condition selection switch is used to switch between the original traction excitation circuit and the improved traction excitation circuit, and the second operating condition selection switch is used to control different functions of the improved traction excitation circuit.

[0025] Furthermore, the traction excitation circuit switching relay opens the contacts of the traction excitation circuit switching relay when the original traction excitation circuit is selected for operation, and closes the contacts of the traction excitation circuit switching relay when the improved traction excitation circuit is selected for operation;

[0026] The second operating mode selection switch, if the train direct power supply system is not required to work, the second operating mode selection switch is set to "0"; if it is necessary to use the improved traction excitation circuit to control the locomotive for traction working condition, the second operating mode selection switch is set to "traction"; if it is necessary to use the improved traction excitation circuit to control the locomotive for power supply working condition, the second operating mode selection switch is set to "power supply"; if it is necessary to use the improved traction excitation circuit to control the locomotive for both traction working condition and power supply working condition, the second operating mode selection switch is set to "traction power supply";

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention relates to an improved traction excitation circuit for a DC-driven diesel locomotive. By modifying the original traction excitation circuit, utilizing existing electrical switches and key components, and adding a new excitation regulation device, the invention utilizes the excess traction power in the locomotive traction mode to power passenger cars. This achieves the function of both traction and power supply for the train, thereby eliminating the need for a power generator car and operator for large passenger car formations. This reduces fuel consumption and noise pollution, improves the riding comfort of passengers in adjacent cars, and has significant social and economic benefits.

[0029] 2. The improved traction excitation circuit of a DC transmission diesel locomotive of the present invention transforms the original traction excitation circuit. Without affecting the original performance and function of the locomotive, a dual backup is formed by the working condition selection circuit and the original vehicle traction excitation circuit. Not only is the switching between the old and new circuits convenient, but the conversion between traction and traction power supply can also be realized, greatly improving the operating reliability of the locomotive. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the invention.

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] FIG1 is a schematic diagram showing the principle of an original traction excitation circuit of an improved traction excitation circuit for a DC drive diesel locomotive according to the present invention;

[0033] FIG2 is a schematic diagram showing the principle of an improved traction excitation circuit for a DC drive diesel locomotive according to the present invention;

[0034] FIG3 is a schematic diagram of a working condition selection circuit of an improved traction excitation circuit of a DC drive diesel locomotive according to the present invention;

[0035] FIG4 is a schematic diagram showing the principle of an improved traction excitation circuit of Example 1 of an improved traction excitation circuit for a DC drive diesel locomotive according to the present invention;

[0036] FIG5 is a schematic diagram of a working condition selection circuit of Example 1 of an improved traction excitation circuit for a DC drive diesel locomotive according to the present invention.

[0037] Among them: 1 is the circuit breaker; 2 is the relay group; 21 is the first relay; 22 is the second relay; 23 is the third relay; 24 is the fourth relay; 3 is the new excitation regulation device; 4 is the disconnection point of the original traction excitation circuit. DETAILED DESCRIPTION

[0038] Here, exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of devices consistent with some aspects of the present invention as detailed in the appended claims.

[0039] As shown in Figure 1, the existing original traction excitation circuit is innovatively designed. On the basis of the original traction excitation circuit, a circuit breaker, a relay group, a new excitation regulating device and a disconnection point of the original traction excitation circuit are added to obtain an innovative circuit topology. The specific modified circuit schematic is shown in Figure 2 as an improved traction excitation circuit. Under the premise that the original performance and function of the locomotive remain unchanged, the improved traction excitation circuit adds a power generation function to the locomotive through the switching equipment in the original traction excitation circuit, and utilizes the newly added circuit breaker, relay group, new excitation regulating device and the disconnection point of the original traction excitation circuit.

[0040] As shown in FIG2 , the improved traction excitation circuit adds a circuit breaker 1, a relay group 2, a new excitation regulating device 3, and an original traction excitation circuit disconnection point 4. The four relays are a first relay 21, a second relay 22, a third relay 23, and a fourth relay 24. Compared with FIG1 , it can be seen that: on the basis of the original traction excitation circuit, the circuit breaker 1, the first relay 21, the second relay 22, and the new excitation regulating device 3 are added, and the third relay 23, the fourth relay 24, and the original traction excitation circuit disconnection point 4 are added to the original traction excitation circuit; the specific positions of the additional components are as follows:

[0041] One end of the circuit breaker 1 is connected to the terminal X4 / 9, and the other end is connected to the first relay 21. One end of the original traction excitation circuit disconnection point 4 is connected to the closed point of the first relay 21, and the other end is connected to the excitation contactor of the excitation generator of the original traction excitation circuit. The original traction excitation circuit disconnection point 4 is set between the resistor Rwq and the resistor Rt1 of the original traction excitation circuit, and the first relay 21 is electrically connected to the original traction excitation circuit disconnection point 4 through a wire.

[0042] The new excitation regulating device 3 is connected to the second relay 22, and the second relay 22 is connected to the connection terminal X7 / 6 in the original traction excitation circuit through a wire;

[0043] The third relay 23 is set between the connection terminal X7 / 9 of the original traction excitation circuit and the excitation regulator 14.15 port of the original traction excitation circuit, and the fourth relay 24 is set between the connection terminal X5 / 8 of the original traction excitation circuit and the positive power supply of the excitation regulator of the original traction excitation circuit.

[0044] When the locomotive only needs to perform traction, the original traction excitation circuit can be used to realize the train traction function; when the locomotive needs power supply, the improved traction excitation circuit can be used. The improved traction excitation circuit can not only realize the traction or power supply function alone, but also realize the traction and power supply functions at the same time.

[0045] When the original traction excitation circuit is working, the open point of the first relay 21 is in the disconnected state, and the closed point of the first relay 21 is in the closed state to connect with the disconnection point 4 of the original traction excitation circuit, thereby connecting the original traction excitation circuit, so that when the improved traction excitation circuit is not working, it will not affect the normal operation of the original traction excitation circuit. The normally open contact of the second relay 22 cuts off the connection with the new excitation regulation device 3, and the normally closed contact of the third relay 23 is connected to the excitation regulator in the original traction excitation circuit. The normally closed contact of the fourth relay 24 is connected to the working power supply of the excitation regulator in the original traction excitation circuit, so that the original traction excitation circuit remains connected and works normally, so that the three-phase AC power generated by the traction excitation generator L in the original traction excitation circuit is rectified by the three-phase bridge of the rectifier device 2ZL to provide excitation current to the excitation winding of the synchronous main generator F. The AC power generated by the main generator is converted into DC power by the rectifier device and provided to the DC traction motor to drive the locomotive.

[0046] When the improved traction excitation circuit is working, the open point of the first relay 21 is in a closed state, the closed point of the first relay 21 is in an open state, and the contact of the second relay 22 is in a closed state to connect to the new excitation regulation device 3, thereby realizing the traction and power generation functions of the locomotive, and the contacts of the third relay 23 and the fourth relay 24 are both in an open state, thereby disconnecting the connection between the improved traction excitation circuit and the excitation regulator in the original traction excitation circuit and the working power supply of the excitation regulator in the original traction excitation circuit, so that the excitation regulator in the original traction excitation circuit does not work, and the improved traction excitation circuit realizes the purpose of traction and power generation functions through the new excitation regulation device 3, and when the improved traction excitation circuit is working, if the current in the improved traction excitation circuit is too large, the circuit breaker 1 is disconnected to complete the overcurrent protection of the improved traction excitation circuit.

[0047] The new excitation regulation device 3 is an LTQ-Z type excitation regulator, which consists of a module power supply, a control chassis, an excitation drive unit (i.e., a voltage regulator), a terminal block, an air circuit breaker, and a sensor. The module power supply is used to provide working power to the new excitation regulation device, the control chassis is used to install the excitation regulation control board, the excitation drive unit is used to adjust the excitation current, the terminal block is used to connect the internal and external circuits, the air circuit breaker is used to implement overcurrent protection and disconnect the circuit, and the sensor is used to detect the voltage and current of the main circuit. If the voltage and current in the main circuit do not meet the requirements, they are automatically adjusted and controlled through a closed loop. The new excitation adjustment device 3 inputs a control signal to the excitation board, and the MCU of the excitation board generates a PWM wave, controls the on and off of the optocoupler, and thus generates a PWM signal output with an adjusted amplitude. The on and off of the IGBT is driven by the voltage adjustment circuit, thereby adjusting the excitation current of the GQL-45 locomotive induction sub-excitation generator. The three-phase AC voltage emitted by the GQL-45 locomotive induction sub-excitation generator is rectified by the rectifier device and converted into DC power, thereby realizing the function of the traction locomotive to supply power to the train.

[0048] Excitation current in the improved traction excitation circuit: (+)110V, X4 / 9→50DZ (circuit breaker 1)→opening point of the first relay 21→Rt1→2HKg→X7 / 5→L excitation generator excitation winding→X7 / 6→second relay 22→new excitation regulation device 3→(-)110V (negative pole of excitation power supply).

[0049] The original traction excitation circuit is newly modified through the circuit breaker 1, the first relay 21, the second relay 22 and the new excitation regulating device 3, the third relay 23, the fourth relay 24 and the disconnection point 4 of the original traction excitation circuit. The original switchgear and other components are borrowed. The improved traction excitation circuit uses the surplus power in the locomotive traction mode to add a traction power generation function to the locomotive through the newly added new excitation regulating device 3, while the original performance and function of the locomotive remain unchanged. As a result, the train power supply generator car and operators added to the large passenger car formation can be eliminated, thereby reducing fuel consumption and noise pollution and improving the riding comfort of passengers on adjacent passenger cars.

[0050] As shown in Figure 3, the improved traction excitation circuit also includes a working condition selection circuit, which controls the relay to switch between the original traction excitation circuit and the improved traction excitation circuit through the working condition selection switch. The working condition selection circuit includes a relay that controls the circuit to be disconnected or connected. The contacts of the relay are connected in series in the improved traction excitation circuit, and the working state of the excitation circuit is controlled by controlling the coil of the relay.

[0051] The operating condition selection switch 1LK (with lock) in the operating condition selection circuit realizes the selection and switching of the original traction excitation circuit and the improved traction excitation circuit of the locomotive. When the original traction excitation circuit is selected to work, the relay in the operating condition selection circuit is disconnected, and the locomotive works normally under the original traction excitation circuit, realizing the locomotive traction function; when the improved traction excitation circuit is selected to work, the relay in the operating condition selection circuit is closed, and the locomotive works normally under the improved traction excitation circuit, realizing the locomotive traction and power generation functions.

[0052] The operating condition selection switch 2LK in the operating condition selection circuit realizes the selection of locomotive functions during the operation of the improved traction excitation circuit. If the train direct power supply system is not required to work, the second operating condition selection switch is set to "0". If the improved traction excitation circuit is needed to control the locomotive for traction working condition, the second operating condition selection switch is set to "traction". If the improved traction excitation circuit is needed to control the locomotive for power supply working condition, the second operating condition selection switch is set to "power supply". If the improved traction excitation circuit is needed to control the locomotive for both traction working condition and power supply working condition, the second operating condition selection switch is set to "traction power supply".

[0053] The improved traction excitation circuit topology borrows the switching devices and other components of the original circuit to achieve the conversion purpose of the original traction excitation circuit to realize the traction function and the improved traction excitation circuit to realize the traction and power supply functions. It realizes the new performance and functions of the locomotive without interfering with the original traction excitation circuit, eliminates the train's power generation car, and uses the surplus traction power in the locomotive traction mode to power the passenger car, realizing the train's function of both traction and power supply, which has extremely high social and economic benefits.

[0054] Example 1

[0055] This embodiment implements the modification of direct train power supply according to the diesel locomotive traction excitation circuit modification principle diagram shown in FIG4 . When modifying the diesel locomotive traction excitation circuit, a circuit breaker 1, a first relay 21, a second relay 22, and a new excitation adjustment device 3 are added to the original traction excitation circuit. A third relay 23, a fourth relay 24, and the original traction excitation circuit disconnection point 4 are added to the original traction excitation circuit. The specific locations of the additional components are as follows:

[0056] As shown in FIG4 , a circuit breaker 1 is added between the terminal LX1:9 and the terminal LX1:10. The circuit breaker model is IC65N DC 1P C10A, rated voltage is 125V, rated current is 10A, and an additional first relay 21 is connected after the circuit breaker 1. The open point of the first relay 21 is connected to the terminal LX4:35, and the closed point of the first relay 21 is connected to the terminal LX4:34. The original traction excitation circuit disconnection point 4 is set between the variable resistors Rt1 and Rwq of the original traction excitation circuit. The new excitation regulation device 3 is connected to the second relay 22. The model of the new excitation regulation device is LTQ-Z type excitation regulator. The working power supply of the LTQ-Z type excitation regulator is DC110V, and the second relay 22 is connected to the terminal X7 / 6 in the original traction excitation circuit through a wire. The third relay 23 is set between the terminal X7 / 9 of the original traction excitation circuit and the terminal X7:3 of the original traction excitation circuit. The fourth relay 24 is set between the terminal X5 / 8 of the original traction excitation circuit and the positive pole of the power supply of the excitation regulator of the original traction excitation circuit.

[0057] When the modified improved traction excitation circuit of the diesel locomotive is working, the open point of the first relay 21 is in a closed state, the closed point of the first relay 21 is in an open state, and the contact of the second relay 22 is in a closed state to connect to the new excitation regulation device 3, wherein the new excitation regulation device 3 is an LTQ-Z type excitation regulator, which is composed of a module power supply, a control chassis, an excitation drive unit (i.e., a voltage regulator), a terminal block, an air circuit breaker, and a sensor. The new excitation regulation device 3 inputs 110VDC, and outputs a 15V voltage through the power module and inputs it to the excitation board. The MCU of the excitation board generates a PWM wave, controls the on and off of the optocoupler, and then generates a square wave signal output with an amplitude of 15V. The square wave signal with an amplitude of the adjusted voltage drives the on and off of the IGBT, thereby adjusting the excitation current of the GQL-45 locomotive induction sub-excitation generator. The adjusted output voltage of the excitation generator is rectified by the rectifier device and converted into direct current, thereby realizing the function of the traction locomotive mechanism to supply power to the train. The contacts of the third relay 23 and the fourth relay 24 are both in the disconnected state, thereby disconnecting the connection between the improved traction excitation circuit and the excitation regulator in the original traction excitation circuit and the working power supply of the excitation regulator in the original traction excitation circuit. When the improved traction excitation circuit is working, if the current in the improved traction excitation circuit is too large, the circuit breaker 1 is disconnected to complete the overcurrent protection of the improved traction excitation circuit.

[0058] As shown in Figure 5, the working condition selection circuit included in the modified improved traction excitation circuit of the diesel locomotive is used to switch between the original traction excitation circuit and the improved traction excitation circuit through the working condition selection switch control relay.

[0059] The operating condition selection switch 1LK (with lock) in the operating condition selection circuit realizes the selection and switching of the original traction excitation circuit and the improved traction excitation circuit of the locomotive. When the original traction excitation circuit is selected to work, the K8 relay in the operating condition selection circuit is disconnected, and the locomotive works normally under the original traction excitation circuit to realize the locomotive traction function; when the improved traction excitation circuit is selected to work, the K8 relay in the operating condition selection circuit is closed, and the locomotive works normally under the improved traction excitation circuit to realize the locomotive traction and power generation functions.

[0060] If the train direct power supply system is not required, set the second operating condition selection switch to "0"; if it is necessary to use the improved traction excitation circuit to control the locomotive for traction operation, set the second operating condition selection switch to "traction"; if it is necessary to use the improved traction excitation circuit to control the locomotive for power supply operation, set the second operating condition selection switch to "power supply"; if it is necessary to use the improved traction excitation circuit to control the locomotive for both traction and power supply operation, set the second operating condition selection switch to "traction power supply".

[0061] In this embodiment, a new circuit topology is created on the basis of the original traction excitation circuit, and the surplus traction power in the locomotive traction mode is used to power the passenger cars, thereby eliminating the need for a power generation vehicle and operators to be added to a large passenger car train. This not only realizes the function of both traction and power supply of the train, but also reduces fuel consumption and noise pollution, improves the riding comfort of adjacent passengers, and has obvious social and economic benefits. Moreover, the modified internal combustion engine traction excitation circuit and the original car traction excitation circuit form a dual backup, which facilitates the conversion between traction and traction power supply without affecting the original performance and function of the locomotive, greatly improving the operational reliability of the locomotive.

[0062] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0063] It should be understood that the present invention is not limited to the above description and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An improved traction excitation circuit for a DC drive diesel locomotive, characterized in that, An improved traction excitation circuit is obtained by adding a circuit breaker (1), a relay group (2), a new excitation regulating device (3), and a disconnection point (4) of the original traction excitation circuit on the basis of the original traction excitation circuit; The relay group includes a first relay (21), a second relay (22), a third relay (23), and a fourth relay (24); One end of the first relay (21) is connected to the circuit breaker (1), and the other end is connected to the disconnection point (4) of the original traction excitation circuit. And the disconnection point (4) of the original traction excitation circuit is connected to the first excitation generator excitation contactor in the original traction excitation circuit; One end of the second relay (22) is connected to the new excitation regulating device (3), and the other end is connected to the tachogenerator in the original traction excitation circuit; The new excitation regulating device (3) is also connected to the excitation winding of the excitation generator in the original traction excitation circuit; One end of the third relay (23) is connected to the excitation winding of the tachogenerator in the original traction excitation circuit, and the other end is connected to the negative power supply of the excitation regulator in the original traction excitation circuit; One end of the fourth relay (24) is connected to the positive excitation power supply, and the other end is connected to the positive power supply input terminal of the excitation regulator in the original traction excitation circuit.

2. The improved traction excitation circuit of the DC drive diesel locomotive according to claim 1, characterized in that, The first relay (21) includes an open contact and a closed contact. The open contact and the closed contact are respectively arranged on two branches. The branch where the open contact is located is connected to the excitation winding of the excitation generator in the original traction excitation circuit. The branch where the closed contact is located is connected to the first excitation generator excitation contactor in the original traction excitation circuit. The open contact is used to control the connection state of the relay and the improved traction excitation circuit, and the closed contact is used to connect the disconnection point (4) of the original traction excitation circuit; The second relay (22), the third relay (23), and the fourth relay (24) have the same structure; The second relay (22) is used to control the connection state between the original traction excitation circuit and the new excitation regulating device (3); The third relay (23) is used to control the connection state between the original traction excitation circuit and the excitation regulator of the original traction excitation circuit; The fourth relay (24) is used to control the working state of the excitation regulator in the original traction excitation circuit.

3. The improved traction excitation circuit of the DC drive diesel locomotive according to claim 1, characterized in that, When the original traction excitation circuit is working, the open contact of the first relay (21) is disconnected, the closed contact of the first relay (21) is closed, the contact of the second relay (22) is disconnected, the contact of the third relay (23) is closed, and the contact of the fourth relay (24) is closed.

4. The improved traction excitation circuit of the DC drive diesel locomotive according to claim 1, characterized in that, When the improved traction excitation circuit is working, the open contact of the first relay (21) is closed, the closed contact of the first relay (21) is disconnected, the contact of the second relay (22) is closed to connect the new excitation regulating device (3), the contact of the third relay (23) is disconnected to cut off the excitation regulator in the original traction excitation circuit, and the contact of the fourth relay (24) is disconnected to cut off the working power supply of the excitation regulator in the original traction excitation circuit.

5. The improved traction excitation circuit of a DC drive diesel locomotive according to claim 1, characterized in that, The improved traction excitation circuit further includes a working condition selection circuit, which includes a first working condition selection switch, a second working condition selection switch, and a traction excitation circuit switching relay. The first working condition selection switch is used to switch between the original traction excitation circuit and the improved traction excitation circuit, and the second working condition selection switch is used to control the realization of different functions of the improved traction excitation circuit.

6. The improved traction excitation circuit of the DC drive diesel locomotive according to claim 5, characterized in that, For the traction excitation circuit switching relay, when the original traction excitation circuit is selected to work, the contacts of the traction excitation circuit switching relay are disconnected, and when the improved traction excitation circuit is selected to work, the contacts of the traction excitation circuit switching relay are closed; For the second working condition selection switch, if the train's direct power supply system is not required to work, the second working condition selection switch is placed in the "0" position. If it is necessary to use the improved traction excitation circuit to control the locomotive in the traction mode, the second working condition selection switch is placed in the "traction" position. If it is necessary to use the improved traction excitation circuit to control the locomotive in the power supply mode, the second working condition selection switch is placed in the "power supply" position. If it is necessary to use the improved traction excitation circuit to control the locomotive in both the traction mode and the power supply mode simultaneously, the second working condition selection switch is placed in the "traction and power supply" position.

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