JPS6160641B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control method for a dual-mode running vehicle configured to be able to supply power for the traction motor in an electric drive vehicle from both the vehicle-mounted power supply equipment and the overhead line power supply from the ground power supply equipment. .

For large construction vehicles and vehicles for transporting ore and topsoil in open-pit mines, electrically driven vehicles with rubber tires are being used instead of mechanically driven vehicles with conventional mechanical power transmission engines, with the aim of reducing vehicle maintenance costs and transportation costs. The transportation capacity of these vehicles has also increased from 120 tons to 320 tons, and the scale is expected to further expand in the future.

For such large vehicles, conventional mechanical vehicles are not only difficult to configure the power transmission engine, but also require too much kinetic energy to be absorbed during braking, making it difficult to use friction-type mechanical braking devices. Since it is huge and difficult to configure, when the vehicle is running, the engine drives the motor, and the converted electric power is used to create multiple electric motors distributed within or near the drive axle. The mainstream is electric drive vehicles that employ so-called power-generating brakes, in which the traction motor acts as a generator when the vehicle is braked, and the vehicle's kinetic energy is dissipated as heat by a brake resistor. There is. At construction sites and mines where such vehicles are used, the mainstream is a trackless transportation method using large tires that incorporates the off-the-road concept from tracked transportation using trolleys and freight cars.

This eliminates the need for laying rails and overhead wires for conventional tracked vehicle transportation methods, and there are no restrictions on transportation methods due to tracked vehicles, making mining plans in mines easier depending on the plan at the time. This is because it has many advantages, such as being able to be changed, the cost of constructing a transportation route is low, and there are few time constraints. Most of the mines that have been developed in recent years use the transportation method that incorporates the above-mentioned off-the-road concept. has been adopted.

By adopting such a transportation method, it has become possible to improve production efficiency in mines and reduce transportation costs.

However, the recent rise in petroleum costs caused by oil shocks has led to an increase in the fuel efficiency of such vehicles, which has forced changes in mine plans, especially in non-oil producing countries. This means that especially in areas where large-scale hydroelectric power generation or coal-fired power generation is possible, such as in Central and South America and Africa, ore transportation methods that use generated power are attracting attention as an attractive construction method that cannot be overlooked. There is.

From this point of view, recently such mines have adopted an off-the-road concept that uses electric power generated by internal combustion engines mounted on vehicles to drive generators (hereinafter referred to as power generators) at quarry loading yards and dumping sites. At energy-intensive locations such as loading ramps, attempts are being made to develop a system in which vehicles are run using overhead wire power supply using trolleys and the like.

In view of the above, the present invention provides a control system for a dual-mode vehicle configured to be able to run on power supplied from both the vehicle-mounted power supply equipment and the overhead power supply from the ground power generation equipment.

Figure 1 is a circuit configuration diagram showing an example of a conventional vehicle control system using a power generator as a drive source, in which 1 is a diesel engine, and 2 is a rotating field type three-phase AC generator directly connected to the diesel engine 1. The stator of the three-phase alternating current generator 2 includes an armature winding 3 and a field 5 of an alternating current exciter 4. Further, on the rotating shaft of the three-phase AC generator 2, there are an armature 6 of an AC exciter 4, a rectifier 7 for rectifying the AC output thereof, and a main generator field 8 excited by the DC output of the rectifier 7. Therefore, when the AC exciter field 5 is excited while the engine is rotating, the armature winding 3
generates three-phase alternating current. 9 is a three-phase full-wave rectifier that converts the output of the three-phase alternating current generator 2 into direct current, which supplies power in parallel to the traction motors 10 and 11 during vehicle propulsion, and connects the traction motors 10 and 11 to a separately excited generator during braking. The fields 14 and 15 of the traction motors 10 and 11 are configured as follows.
It is used to energize. Traction motor 10,
11 is a DC motor, 12 and 13 are respective armatures, and 14 and 15 are field magnets. In this configuration, when the vehicle is propelled, the power running contactors 16 and 17 are closed, the two traction motors 10 and 11 are connected in parallel, and the two traction motors 10 and 11 are connected in parallel and driven in parallel by the output of the three-phase alternating current generator 2. When braking the vehicle, the brake contactors 18, 19, and 22 are closed and the armature 1
Resistors 20 and 21 for dynamic braking are connected in parallel to 2 and 13, and the fields 15 and 14 are configured to be energized by the output of the three-phase alternating current generator 2 via a contactor 22. With this configuration, the traction motors 10 and 11 perform dynamic braking.

In a traveling vehicle with such a configuration, for example, an electric dump truck, the vehicle operation control method is the same as in conventional mechanically driven vehicles, in which the vehicle propulsion circuit is configured by pressing the accelerator pedal, and at the same time, the diesel engine fuel injection control the amount,
The engine speed is increased from the idle speed to the rated speed, and the engine speed can be arbitrarily controlled from the idle speed to the rated speed according to the amount of depression of the accelerator pedal.

The reason why the engine speed is adjusted in accordance with the amount of depression of the accelerator pedal is to improve the comfort of the driver's cabin, improve fuel efficiency, and reduce mechanical wear on the engine and the like.

In order to enable the vehicle to run smoothly with the above configuration, the control of the generator, which is directly connected to the diesel engine and converts the power obtained by the diesel engine into electrical energy, must be coordinated with the output of the diesel engine. Vehicles must be operated in a manner that does not cause the engine to stall. For this reason, the power generator is controlled as shown below.

FIG. 2 is a diagram showing the output characteristics of a diesel engine, with the horizontal axis showing the engine rotational speed and the vertical axis showing the engine net shaft output. As shown in FIG. 2, while a stable maximum engine net shaft output is obtained near the rated rotation speed A, the output characteristics become unstable in the low rotation speed region.
Moreover, when the rated rotational speed A is exceeded, the output obtained rapidly decreases. In order to use a diesel engine with the above output characteristics and create a stable power generator, the generator output must be controlled according to the engine speed so that it does not exceed the engine net shaft output at that speed. There must be.

For this reason, for example, if the generator output is controlled in proportion to the engine speed as shown in characteristic A in Figure 3, the generator output can be reliably lower than the engine output in the low engine speed region, and the efficiency can be increased. It is possible to obtain stable maximum output near the rated rotation speed A with good speed.

For the reasons mentioned above, the generator control of the prime mover is generally performed as shown in characteristic A shown in FIG.

In order to carry out such control, a frequency-voltage converter 23 that detects the engine rotation speed from the output of the three-phase alternator 2 shown in FIG. 1, a PT 24 that detects the output voltage of the three-phase full-wave rectifier 9, A CT25 that detects the same output current, and a multiplier 26 that receives the signals of the PT24 and CT25 and detects their product, that is, the power.
Accordingly, the engine rotation speed and the output power of the three-phase alternator 2 are determined.

Both signals obtained in this way are given to the controller 27 that controls the field 5 of the AC exciter 4, and the engine rotation speed (frequency-voltage converter 23) and the output power of the three-phase alternator 2 are The controller 27 controls the above characteristics. Since the diesel engine 1 and the three-phase alternator 2 are operated in coordination with each other by the above control, the output characteristics of the three-phase alternator 2 are as shown in FIG. 4.

FIG. 4 is a diagram showing the output characteristics of a three-phase alternating current generator, with the horizontal axis representing the output current and the vertical axis representing the output voltage. In the figure, curve a is the output characteristic obtained when the excitation of field 8 is constant, and curve b
is a characteristic of constant power. Therefore, when the engine net shaft output has the characteristic of curve b, the output characteristic curve a of the three-phase alternating current generator 2 has the region shown in the figure as follows.
Excessive than engine net shaft output. Therefore, by controlling the output of the three-phase alternator 2 to the predetermined power as described above,
The output characteristics are those shown by diagonal lines in FIG.

This control allows the motor generators to operate in a coordinated manner, allowing the vehicle to arbitrarily adjust its traction force according to the amount of depression of the accelerator pedal, allowing smooth and stable vehicle operation.

In addition to the above-mentioned control, when the vehicle is being towed, armature current limitation (Fig. 4- _p ) is generally provided to protect the traction motor, and this control is carried out by the controller 27. Do it with

The object of the present invention is to arbitrarily switch the driving source of a vehicle that runs on this principle to a method other than the one shown here, such as using a trolley overhead wire or the like, to receive power from a ground power supply facility. The objective is to provide a running vehicle at the lowest possible price.

Hereinafter, the present invention will be explained based on the drawings of the embodiments.

FIG. 5 is a configuration circuit showing one embodiment of the present invention,
Products with the same numbers as those in FIG. 1 indicate products with the same functions. In FIG. 5, when traveling with a motor generator, the pantograph 28,
29 is lowered, and the vehicle is driven by the diesel engine 1 under the control described above.

When running on ground power, the vehicle is accelerated by the control described above, and then the pantographs 28 and 29 are raised by means other than those shown here, and the pantograph 28 is connected to the (+) overhead wire installed above the ground. is connected to the (-) overhead wire, and power is supplied from the ground power source to the train. In this state, the ground power supply voltage is detected by the PT 30, and the output of the PT 30 and the output voltage of the three-phase alternating current generator 2, that is, approximately the reverse induced voltage of the traction motors 10 and 11, are detected.
The output voltage difference between both PTs 24 and 30 is detected by the PT 24, and the output voltage difference between the two PTs 24 and 30 is detected to be smaller than a predetermined constant value, and the control coil 32R of the contactor 32 is activated. Excite.
When the control coil 32R is excited, the contactor 32 is closed, and the ground positive electrode power supply → pantograph 2
8 → Contactor 32 → Limiting resistor 34〓〓〓〓〓〓〓〓
〓〓〓〓〓〓 In the process of pantograph 29→ground negative electrode power supply, a current value obtained by dividing the above-mentioned voltage difference by the resistance value of the limiting resistor 34 flows to the traction motors 10 and 11 and is driven.

At the same time, the contact 32 moves in conjunction with the contactor 32.
The field 5 of the AC exciter 4 is cut off by RC,
As a result, the output of the three-phase alternating current generator 2 is rapidly throttled and the drive source of the traction motors 10 and 11 is switched from the diesel engine 1 to the ground power source.

This allows the vehicle to connect ground power to the pantograph 2.
The vehicle will receive power and start running on August 8, 29. Next, in this embodiment, when running on ground power, when running on the diesel engine 1 described above, there is no power restriction due to cooperation between the diesel engine 1 and the three-phase alternator 2, so this embodiment In this case, the ground power supply voltage is set to a voltage value higher than the maximum voltage obtained by the three-phase alternating current generator 2, and the configuration is such that high-speed performance can be obtained.

Therefore, when switching from the driving mode using the prime mover generator to the driving mode using the ground power source, since the limiting resistor 34 is inserted into the drive circuit, the current flowing through the limiting resistor 34 is detected by the controller 31 (i.e., the current flowing through the limiting resistor 34 is detected by the controller 31 (i.e., The voltage is PT30 and the traction motor voltage is PT24.
The controller 31 detects the output difference between both PTs 24 and 30.
If the value is smaller than a predetermined constant value, the contactor 33 is detected by the output of the controller 31.
The control coil 33R is excited.

As a result, the limiting resistor 34 is short-circuited, and the traction motors 10 and 11 are driven by the ground power source according to the characteristics determined by the motor characteristics.

Through the control described above, the vehicle changes from the driving mode using the prime mover to the driving mode using the ground power source.
without using expensive and complicated chopper devices or resistance starting devices that control multiple contactors in combination.
Can be smoothly transitioned.

In the above explanation, the switching from the driving mode using the motor generator to the driving mode using the ground power source was controlled by the voltage difference between the two power sources, but since the ground power source voltage is a substantially constant value, the vehicle speed, that is, the rotation of the traction motor It can be seen that substantially similar control values can be obtained even if the control is performed numerically.

FIG. 6 shows an example of the configuration of the main parts of the control circuit, in which numeral 35 is a tachogenerator attached to the end of the traction motor shaft to detect the vehicle speed, and the output of the tachogenerator 35 is detected by a controller 36, similar to that shown in FIG. , control coils 32R' of contactors 32 and 33 shown in FIG.
33R' is controlled. This makes it possible to perform control substantially similar to the voltage difference described above.

Although not shown, the controller 3 shown in FIG.
6 is given the signal of PT30 shown in Fig. 5, and using the arithmetic method commonly used for general control,
By shifting the operational setting values of 32R' and 33R' in proportion to the ground power supply voltage, the influence of ground power supply voltage fluctuations can be made smaller than in the case of FIG.

In the above explanation, the on-vehicle power supply is explained only as a drive system that combines the diesel engine 1 and the three-phase alternator 2, but there is nothing that can be done even if this is configured with a battery or the like mounted on the vehicle. It's no good.

As described above, according to the present invention, in a dual mode vehicle configured to run on either on-board power source or ground power source, the control device can be made as small and simple as possible, and at the same time, an optimal control system can be provided.

In the above explanation, the ground power supply was explained as DC, but the same effect can be achieved even if the AC overhead power line is used and rectified on the vehicle.The motor generator is configured with a DC generator, so that the current does not flow from the ground power supply to the DC generator. It goes without saying that the same thing can be done by connecting a rectifier.

As explained above, according to the present invention, it is possible to provide the most inexpensive and reliable dual mode vehicle control system, and its effects are great.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing an example of a conventional vehicle control system using a power generator as a drive source, and Figures 2, 3, and 4 show the output characteristics of the diesel engine and three-phase alternator. Characteristic diagram for explanation,
Fig. 5 is a circuit configuration diagram showing an embodiment of the present invention in which the vehicle drive source is configured to run using either a prime mover or a ground power source, and Fig. 6 is a main part configuration of a control circuit of another embodiment of the present invention. FIG. 1... Diesel engine, 2... Rotating field type three-phase AC generator, 3... Armature winding, 4... AC exciter, 9... Three-phase full-wave rectifier, 10, 11... Traction motor , 16-19, 22, 32, 33... Contactor, 23... Frequency-voltage converter, 24, 30
...PT, 25...CT, 26...multiplier, 27,
31, 36... Controller, 28, 29... Pantograph, 32R, 33R... Control coil, 32
RC...Contact point, 35...Tachogen.

Claims (1)

[Scope of Claims] 1. A ground power source with a substantially constant voltage is collected in a traveling vehicle equipped with a power generation means capable of operating a DC motor, which is a traction motor for a traveling vehicle, at an arbitrary speed, and a power control means on the vehicle. It is also equipped with a current collector capable of generating electricity, and when the DC motor is driven from the ground power source, the electric power generation means and the electric power control means provided on the vehicle in advance are used to make the vehicle run and stop the vehicle. The vehicle drive power source is switched from the electric power generating means provided on the vehicle to the ground power source while the vehicle is running without any movement, and the direct current motor is directly driven by the ground power source without going through the electric power control means on the vehicle. A dual mode vehicle control system characterized by being configured to run a vehicle. 2. In the dual-mode traveling vehicle control system described in claim 1, a predetermined vehicle speed is used as a control means for switching the drive power source of the traction motor for the traveling vehicle from the electric power generation means provided on the vehicle to the ground power source. A dual mode vehicle control system characterized by being configured to switch between the two modes. 3. In the dual mode running vehicle control system as set forth in claim 1, the control means for switching the drive power source of the traction motor for the running vehicle from the electric power generating means provided on the vehicle to the ground power source is configured to control the ground power supply voltage and the direct current. A dual mode vehicle control system characterized by being configured to switch after confirming that the difference between the voltage and the motor induced voltage is smaller than a predetermined differential voltage. 4. A dual mode vehicle control method according to claim 2, characterized in that the vehicle speed determined in advance is changed in proportion to the ground power supply voltage.