Arrangement for supplying a rail vehicle with electrical energy

Abstract

The invention relates to an arrangement for supplying a rail vehicle with electrical energy. One electrical machine is allocated to each of at least two internal combustion engines for generating electrical energy. A common controller is designed to start the internal combustion engines individually as required. At least one pre-heating device is designed to pre-heat the internal combustion engines before a start. A temperature detection device is thermally coupled to the internal combustion engines. The controller is designed, during an operation of one of the internal combustion engines, to start another of the internal combustion engines if, due to cooling of the other internal combustion engine, a temperature of the other internal combustion engine detected by a temperature identifying device reaches or exceeds a temperature threshold.

Claims

1. An arrangement for supplying a rail vehicle with electrical energy, the arrangement comprising: at least two internal combustion engines, each having an associated electrical machine for generating electrical energy, wherein the electrical machine is coupled mechanically with the internal combustion engine so as to be driven by the internal combustion engine when the electrical machine is in generator operating mode so that at least one first and one second internal combustion engine-machine combination are formed, a common control of the internal combustion engine-machine combinations wherein the common control is designed to start the internal combustion engines individually as required, at least one preheating device designed to preheat the internal combustion engines before a start, at least one temperature determining device coupled thermally with the internal combustion engines and connected to the common control by a signal link to transfer information about temperatures of the internal combustion engines to the common control, wherein the common control is designed, while one of the internal combustion engines is running, to start another one of the internal combustion engines when, a temperature of the other internal combustion engine determined by the at least one temperature determining device reaches or drops below a first predefined temperature limit, and wherein, the common control reduces the engine power of one or more of the internal combustion engines already in operation as soon as the other internal combustion engine has started and contributes to a total engine power of all internal combustion engines in operation.

2. The arrangement as claimed in claim 1, wherein the common control starts the other internal combustion engine when the first predefined temperature limit is attained even though engine power of one or more of the internal combustion engines already in operation suffices for supplying the rail vehicle with electrical energy.

3. The arrangement as claimed in claim 1 comprising a ventilation device assigned to each of the engine-machine combinations comprised of one or more ventilation units wherein the ventilation units are activated only when the internal combustion engine of the engine-machine combination associated with it is in operation and when the temperature of the engine-machine combination associated with it satisfies a second predefined temperature limit.

4. A rail vehicle comprising the arrangement as claimed in claim 1.

5. A method for operating an arrangement for supplying a rail vehicle with electrical energy comprising: operating simultaneously at least two internal combustion engines, each having an associated electrical machine for generating electrical energy, each of which is coupled mechanically with the internal combustion engine so that in generator operating mode of the electrical machine it is driven by the internal combustion engine and at least one first and one second internal combustion engine-machine combination are formed, measuring information about temperatures of the internal combustion engines, with at least one temperature determining device coupled thermally to the internal combustion engines and connected to a common control, starting, while one of the internal combustion engine-machine combinations is running, one other of the internal combustion engines when, a temperature of the other internal combustion engine determined by the at least one temperature determining device attains or drops below a first predefined temperature limit, reducing the engine output of one or more of the internal combustion engines that are already in operation as soon as the other internal combustion engine has started and contributes to a total engine power of all internal combustion engines in operation.

6. The method of claim 5, further comprising the step of starting the other internal combustion engine when the first predefined temperature limit is attained even though an engine power of one or more of the internal combustion engines already in operation suffices for supplying the rail vehicle with electrical energy.

7. The method of claim 5, further comprising the steps of ventilating each of the engine-machine combinations by one or more ventilation units associated with it wherein the ventilation units are activated only when the internal combustion engine of the engine-machine combination associated with it is in operation and when the temperature of the engine-machine combination associated with it satisfies a second predefined temperature limit.

8. The method of claim 5, further comprising the step of preheating the internal combustion engines before starting the internal combustion engines.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will now be described with reference to the attached drawings. The different figures in the drawings represent schematically:

(2) FIG. 1 one embodiment of an arrangement for supplying at least one traction motor and additional electrical auxiliary devices in a rail vehicle with electrical energy,

(3) FIG. 2 a control system in a rail vehicle,

(4) FIG. 3 a top view of an engine space with three engine-machine combinations associated to each of which is one ventilation unit, and

(5) FIG. 4 a flow chart illustrating the sequence of the control of the operation of a plurality of internal combustion engine-machine combinations.

DETAILED DESCRIPTION OF THE INVENTION

(6) The embodiment shown in FIG. 1 comprises a plurality of internal combustion engine-machine combinations 1, 3, wherein the internal combustion engines 1a, 1b, . . . 1n are preferably diesel engines. The electrical machines 3a, 3b, . . . 3n are, e.g., permanent magnet synchronous motors. Shown are three specimens each of the component, with the three dots between the combinations 1b, 3b and 1n, 3n indicating that still other specimens can exist. Each of the internal combustion engines 1 is coupled, by a drive shaft with coupling 2a, 2b, 2n, to the associated electrical machine 3.

(7) Each of the combinations 1, 3 is connected, by a three-phase connection line 4a, 4b, 4n, to a generator rectifier 5a, 5b, 5n assigned to the combination 1, 3. The rectifiers 5 are connected with a DC link by lines 8, 10.

(8) Each of the engines 1 is combined with a cooling circuit 18a, 18b, . . . , 18n in which cooling liquid circulates and cools the engine 1 when the cooling circuit 18 is in operation. Each cooling circuit 18 is combined with at least one temperature sensor 19a, 19b, . . . 19n which measures the temperature of the cooling liquid. As shown by the dashed line on top in FIG. 1 only for the temperature sensor 19a, the temperature sensors 19 are connected, by a signal link, with the control 17 which controls the operation of the combinations 1, 3. The dashed line from the control 17 to the combination 1a, 3a shown on top in FIG. 1 indicates that the control can control the operation of each of the combinations 1, 3, more particularly it can start and stop the respective internal combustion engine 1.

(9) The two conductors of an auxiliary devices inverter 12 on the direct voltage side are connected to the lines 8, 10 of the DC link. On its alternating voltage side, the auxiliary devices inverter 12 is connected electrically to a ventilation unit 13 for ventilating and thereby cooling the internal combustion engine-machine combinations 1, 3, where the ventilation units 13 are represented schematically by a square. FIG. 3 illustrates a concrete embodiment in which four ventilation units are shown.

(10) Also connected to the DC link are a traction motor inverter 14 and a bus bar inverter 15. During the operation of the rail vehicle the traction motor inverter 14 supplies at least one traction motor with alternating current and therefore with electrical energy. The bus bar inverter 15 supplies, via a train bus bar 16, electrical consumers such as, for example, the air-conditioning system, heaters, lighting system. In addition to the ventilation units 13, the auxiliary devices inverter 12 or another auxiliary devices inverter not seen can supply other auxiliary devices with electrical energy from the DC link.

(11) When the electrical consumers connected to the DC link do not need the maximum possible electrical power which the internal combustion engines 1 can generate through their electrical machines 3, individual combinations 1, 3 can be turned off because of the plurality of the internal combustion engine-machine combinations 1, 3, i.e., the internal combustion engine of the combination is out of operation. Alternately such a combination can operate at idle speed of the internal combustion engine. The decision of turning off the internal combustion engine or an idle mode can be made by an automatic control, e.g., a driver assist system. Alternately, the driver, i.e., the train operator, himself can make or influence the decision.

(12) The number of combinations 1, 3 to which the generation of electrical energy is split can be made particularly depending on the momentary power demand or the requested power requirement. In particular, the power demand and the requested power requirement can be referenced to predefined power thresholds, for which information for the operation of the engine-machine combinations is stored.

(13) Illustrated in FIG. 2 are entries which, e.g., the driver or the driver assist system provide for the operation of a control represented by the INP block in FIG. 2. They are sent to a higher-level vehicle control TOP. The higher-level vehicle control TOP has, in particular, the function of preparing operating values, e.g., the power balance sheet of the controlled engine-machine combinations and setting priorities for the selection of the internal combustion engines of the arrangement for operation.

(14) As indicated by arrow A, the higher-level vehicle control TOP controls the operation of a lower-level engine-machine control or regulation REG. The purpose of this lower-level control REG is to control the start and stop of the different internal combustion engines of the arrangement MOT (as indicated by arrow B) while, in particular, paying attention to a balanced load or balanced operation of the internal combustion engines over longer periods of time. The combination of the controls TOP, REG is an embodiment of the control 17 illustrated in FIG. 1. As indicated by double arrow C, the higher-level control TOP and the lower-level control REG exchange information between each other during operation. For example, the lower-level control REG transfers information about the balanced or unbalanced utilization of the different internal combustion engines to the higher-level control TOP. Corresponding information is, e.g., process variables such as speeds, temperatures, electrical currents, but also fault messages. The higher-level control TOP transfers to the lower-level control REG particularly for each of the internal combustion engines a power setpoint and/or the specification which internal combustion engines shall operate (arrow A). Except the start and stop instructions, the lower-level control REG also transfers to the engine-machine combinations power and/or speed setpoints.

(15) The electrical consumers that supply particularly the traction motors, the auxiliary devices and the consumers supplied via the train bus bar are illustrated schematically by the block CON in FIG. 2. Control instructions and other specifications can be sent by the higher-level control TOP to the consumers (arrow G), e.g., traction forces for the traction system and braking forces for the brake system. Reversely, the consumers CON can send information about their operation (e.g., actual electrical powers or forces) as well as fault messages to the higher-level control TOP (arrow D).

(16) The designation EXH illustrates the exhaust system of the internal combustion engines. This also includes particle filters, particularly in case of diesel engines. The particle filters transfer information about their load with particles to the higher-level control TOP (arrow E).

(17) The cooling device KUL for cooling the internal combustion engines and the engine-machine combinations, respectively transfers to the higher-level control TOP information about their operation such as, e.g., temperatures and fault messages (arrow F). The cooling device KUL is combined with a preheating device which can heat up the cooling liquid in a cooling circuit to preheat the engine before starting it.

(18) The time at which internal combustion engines are started or stopped during part load operating mode depends particularly on the present and future total power demand. If the future total power demand is not known as is the case, for example, with an available stored load profile or in the case of an appropriately designed driver assist system, it is possible, in particular, that the vehicle driver provides information about the future power demand to the control system. For example, the vehicle driver can, in this way, communicate a forecast of the future total power demand to the system. The vehicle driver can do this, e.g., by selecting a predefined operating mode. Alternately or additionally, the vehicle driver himself can enter the engines to be operated or at least the number of engines to be operated.

(19) In the special embodiment of FIG. 3, four internal combustion engine-machine combinations are disposed together in a machine space 21, which comprises a central aisle 22. The space for the vehicle driver is located, e.g., to the right of the machine space 21, as the arrow on the right in FIG. 3 indicates. The different internal combustion engines, e.g., diesel engines, are designated by reference codes DM1, DM2, DM3 and DM4. Some vibration dampers of the engines DM are identified by small circles with the reference signs 23a to 23d. Each of the engines DM is coupled mechanically, by a drive shaft not shown in detail, to an electrical machine G1, G2, G3, G4. Disposed in the power train between the internal combustion engine DM and the electrical machine G, more particularly in the area of a coupling of the power train, is a temperature sensor each 25a, 25b, 25c, 25d.

(20) The engine-machine combinations are disposed in a common machine space 21, not completely separated into parts so that an air exchange can take place in the machine space 21. Air inlet openings with at least one fan 27a, 27b, 27c, 27d each are provided in the side walls 26a, 26b of the machine space 21, which also form the external walls of the rail vehicle. The fans 27 take ambient air into the rail vehicle through the side walls 26 into the machine space, with each of the ventilation units being assigned to one of the internal combustion engine-machine combinations, i.e., the air flow taken in cools primarily the associated combination. The air outlet is provided, e.g., in the roof area of the machine space. The fans are operated particularly depending on the temperature measuring values that are measured by the temperature sensor 25 assigned, in each case, to the same internal combustion engine-machine combination.

(21) The cooling air taken in by the fans from outside during their operation at first flows along the internal combustion engine DM and then past the electrical machine G until the warm cooling air exits through the roof into the atmosphere.

(22) In the embodiment in FIG. 3, in particular, the temperature sensors are disposed in the machine space in such a way that the components to be protected from excessive temperatures such as the coupling between engine and machine, the electrical machine contactors and the vibration dampers 23 can be monitored for excessive temperatures. Therefore, in particular, more temperature sensors than shown in the embodiment of FIG. 3 can be provided. For example, in this case, the highest temperature value of the engine-machine combination measured is used as temperature measuring value for the control of the associated ventilation unit.

(23) In the following, an embodiment of a method is described by which engines can be selected for operation and therefore for the generation of electrical power. This is done with reference to FIG. 4. At step S1, at the beginning of the operation of a rail vehicle, at first all internal combustion engines of the arrangement are started, optionally in succession, as is known from the state of the art. At the following step S2, some of the internal combustion engines are turned off again because only a part load operation mode is foreseen for the momentary operation phase. Alternately, not all internal combustion engines are started at step S1 so that, at step S2, no internal combustion engine is turned off or fewer internal combustion engines are turned off. More particularly, the internal combustion engine which has, or the internal combustion engines which have, not been started are preheated in this case.

(24) At the following step S3, the temperatures of the turned off internal combustion engines are monitored. If it is found that the temperature of one of the internal combustion engines drops below a predefined temperature limit, the engine is started (again) (step S4) to avoid cooling down with subsequent preheating of the engine.

(25) In a subsequent operation phase (step S5), which alternately can also take place before or during the operation phase of the steps S2 and S3, the temperature of at least one of the internal combustion engine-machine combinations is monitored constantly and the ventilation device for ventilating and therefore cooling the associated combination operated only when a predefined temperature limit is exceeded. When another temperature limit that is below the aforementioned temperature limit is not met, the operation of the associated ventilation unit is waived, i.e., the unit remains turned off, even during the operation of the associated internal combustion engine. When the lower predefined temperature limit is exceeded and the associated internal combustion engine is in operation, the associated ventilation unit operates (step S6).