DE2405198A1 - BATTERY OPERATED TRANSPORT SYSTEM, ESPECIALLY FOR PUBLIC TRANSPORT - Google Patents

Description

Battery operated transport system, especially for the public Local Transportation The present invention relates to a battery powered transportation system for traffic on roads or rails.

It is particularly aimed at a traffic system in which relatively short journeys between stops take place, such as z0B. in the inner-city Public transport services.

The means of transport used for urban mass transport have remained practically unchanged over the past 50 years. Under these A distinction is to be made between those that are mass transport one have their own routing, such as trams, suburban trains, subways and monorails, and those who drive on the same traffic areas as private traffic, such as the bus. In the latter category, distinctions can again be made are divided between fully autonomous systems using e.g. diesel-powered buses, and semi-free systems, which in the context of a bound route guidance a certain Allow a degree of freedom in traffic, such as with the trolleybus, in short Called 0 bus.

In the last few years one could observe that the trams gradually disappear, since their rail-bound nature makes it impossible for any obstacles Kind of overcome along the line. In the absence of a separate route, there is a tram often so wedged into the heavy individual traffic that those can be reached with them Average speeds become unacceptably low for the audience.

As a result, the bus is the most widely used means of transport almost everywhere in local public transport, since it has the highest degree of mobility and the has the best adaptability to the traffic flow and the routing. The drive system used here, the diesel engine, however, has a heavy one Disadvantage that is increasingly no longer overlooked in the interests of environmental protection becomes: The air pollution from its exhaust gases, which also takes place when that Vehicle e.g. is at the stop and the noise caused by the engine. Another The disadvantage is the waste of energy due to the low overall efficiency of the drive system, a question that especially under the aspect of Energy shortages must be taken into account.

The electrically operated O-bus is not a fixed one Route bound like the tram and therefore seemed a serious one for a long time Competitor for the tram, since it runs almost noiselessly, not the air contaminated, good driving characteristics due to the elasticity of the electric drive system and can adapt to the flow of traffic to a certain extent. Still has it was only used to a limited extent, since such a system was also considerable Has disadvantages: The installation costs for the line network are proportionate large and its maintenance is quite expensive, because of the double polarity complicated structure of the contact wire arrangement is very prone to failure. In addition, Changes in the route are practically impossible. Even in the given The trolleybus has only limited freedom of movement, as its Pantographs detach themselves from the double catenary when the trolleybus around obstacles to avoid, veers too far out of the lane.

One therefore has to find new means of mass transport for the inner city Looking for traffic that is free of its own route and that is in traffic can move freely and have the advantages of electrical operation. However, none of the proposed solutions has so far been entirely satisfactory.

For example, a system has already become known in which electrical powered vehicles get their energy from batteries. To date, however, has no way found to implement this system satisfactorily because the energy source, d, h, the battery or the accumulator according to the current state of the art is a fundamental one Has the disadvantage, namely the very low value of the storable energy, related on the unit of weight compared to fuels such as z0B0 diesel fuel or gasoline.

It should be noted that if the conditions are the same, i.e. if same mileage, the ratio between the weight of the battery to be carried and that of diesel fuel with today's state of the art is about 100: 1, that can perhaps be reduced to 20: 1 in the next few years, provided that the ongoing investigations bring the hoped-for success. In other words, 120 1 Diesel fuel that weighs around 100 kg, a common normal one for the bus Quantity, contains as much energy as an accumulator that weighs about 10 tons. The latter Weight can possibly be reduced to 2 t in the next few years, however, it still puts a significant strain on the vehicle.

An idea, this inadmissibly high weight for the operation of the electric Vehicle reduction (apart from the cost) is in the early 1970s Germany became known from investigations by an industrial group.

After that, the radius of action is taken into account with a certain reserve reduced to a predetermined fraction, so that the battery weight accordingly is decreased. These are in a network of stations within a few minutes exchanged. While the vehicle is back on the road with the new batteries is smuggled in, the batteries removed from the vehicle are in the stations recharged.

This solution has the following problems. The service of the vehicle must be interrupted, which is required quite often, every hour for about five minutes to replace the batteries. It has to be a network of stations set up and maintained so that the batteries can be changed quickly can be. The accumulators have to be recharged in the stations. Both require a considerable amount of personnel. Also is for every vehicle a larger number of battery packs is required as the charging time is longer is than the service life in operation, in order to ensure a quasi-uninterrupted operation enable. These difficulties are e.g. in the report in the magazine "Product Engineering, May 1971 Page 23, titled" German Electric Prototype Vehicle Features Fast eRefuelt Stops ”.

Another well-known proposal, the requirements of the urban Satisfying transports in an ideal manner became unsuccessful in the 1950s carried out by the OERLIKON company in Zurich: the vehicle looked like a Trolleybus off because it was equipped with pantographs. However, it was not a catenary system Installed. Rather, a high-mass gyro was arranged in the vehicle, which was driven by an electric motor was driven at high speed Energy at the stops via the pantograph and corresponding contacts. While During the journey, this top served as a kinetic energy store, it drove you Generator, which in turn was the source of electrical energy for an electric motor.

This system has not found widespread use because there are some essential ones Inconvenience. For example, the value of the energy to be stored is very high limited and therefore also the The vehicle's range of action is very small. It was about a kilometer for a normal bus weight and performance compared to a 0 bus. The time for the gyro to get going was relatively long and critical (every kilometer needed a standstill of approx. 2 minutes). Since it was a dynamic accumulator, could the stored energy cannot be stored indefinitely, it is reduced in the Relatively quickly over time due to the effects of friction. The coupling organs and the regulators for generated voltage and current were proportionate The uncomfortable driving behavior of the vehicle was complicated and could not be overlooked as a result of the precession forces of the gyro with dynamic inclinations of the vehicle.

This idea was recently proposed by an American airline company taken up again, with the help of the most diverse technological solutions The attempt was made to determine the value of the specific energy that can be stored in the flywheel are to be multiplied by a larger radius of action compared to the solution from Oerlikon.

It was suggested to like the vehicle on part of the route to operate an O-bus, i.e. a contact wire system had to be installed, and the vehicle in the sections of the route that are not equipped with an overhead contact line to operate with the help of the energy obtained from the gyroscope. A report on this can be found in the journal "Product Engineering" from July 20, 1970, page 80 and of April 12, 1971, page 54. This means that the vehicle is subject to the same uncomfortable driving characteristics caused by the precession forces of the gyro at. DT-OS 2 161 266 also shows this solution.

DT-OS 2 121 566 suggests energy storage as a modification of this idea for operation on wireless routes with the help of batteries in the vehicle to undertake. As with the system described above, however, there is again an overhead line network necessary in certain sections> making this system to a large extent again inherent the same disadvantageous properties as those of the usual ones O-bus systems are known.

The present invention is based on the object of a battery-operated Transport system to indicate that all the disadvantageous properties of those previously described Systems and in particular a high degree of freedom and security guaranteed in the course of operations.

According to the present invention, this object is achieved by that batteries are used in the vehicle with a charge capacity that covers a distance enable multiple stop sequences and can be recharged quickly, that the reloading time is only a fraction of the driving time, and that at least some of the stops are equipped with electrical supply connections and the vehicle is provided with appropriate connecting means.

The supply connections expediently consist of an over the roadway, e.g. installed at a bus stop above the parking bay Rail and a contact strip embedded in the road surface, and the vehicle is accordingly with top and bottom, preferably extendable pantographs fitted.

The invention thus proposes a system that is also used in temporary failure of the public power supply in a certain way Mass is able to maintain operations, which is especially true for an underground operated traffic is important. Because of the lack of a catenary network is the susceptibility to failure is reduced to a minimum, the vehicle does not produce any exhaust gases and annoying noises, while the vehicle is stationary, there is no energy consumed and the environment is not spoiled by annoying overhead lines.

Further refinements and advantages of the invention emerge from the following Description, here with reference to the drawings, an advantageous Embodiment is explained. In the drawing, Fig. 1 shows in perspective schematic representation of a vehicle for a battery-powered transport system according to the present invention at a stop; Fig. 2 partially broken in rough outlines a side view of the illustration in FIG. 1 with emphasis the electrical connection accessories; 3 schematically shows a traffic network with stops and supply lines for those places where the batteries of the vehicle should be reloaded.

All urban transport run predetermined during operation Trips from that in routes with a series of stops of certain mutual Distance are divided. The density of stops depends on the characteristic of Means of transport and the traffic density and depends in particular on the Claims of users who seldom walk up more than half a kilometer want to travel to the next stop.

Usually the distance between stops is a few hundred meters in the interior of a city and decreases with increasing distance from City center too.

In the case of a subway, the mean distance between stops is about 1 km, in the case of a vehicle traveling above ground, this is usually 200 m were proposed, for example, by the Urban Technology Conference in 1971.

The operational sequence of the aforementioned means of transport is characterized through a sequence of regular cycles in which travel sections and stop sections (for getting on and off passengers). It was found> that the average journey time between two stops is usually less than one Minute and grows to two minutes in heavy traffic. The average Stopping time at a stop is between 5 and 15 seconds. One can so say that the ratio of driving time to stopping time is about 10: 1 and rarely reached 20: 1.

The present invention is based on the knowledge that during When driving, the engine does not have to do work all the time in which no electrical energy is consumed. These are e.g.

the sections of the route in which the vehicle is idling or during is braked. This means that the period of time is consumed during the energy is generally not greater than ten times the holding time the invention before> the skills new types of accumulators exploit that are able> without damage within a short period of time Absorb energy with an amperage that is several times that during normal Driving is the average current intensity.

Although the generally known and applied norms for reloading of accumulators prescribe long periods of time, usually many hours and those The maximum charging current should not be greater than the nominal value in order to avoid damage to avoid on the plates and excessive heating of the electrolyte with subsequent To prevent excessive gas formation, it was found that these phenomena for certain types of accumulators only at very much higher currents than the nominal current strength and occur only after a much longer time. These Phenomena do not show up in practice when the very high charging current is only a few Flows for seconds. Taking advantage of this fact, the invention proposes such Use accumulators that run in a fraction of the discharge time with very high Currents can be recharged. The invention thus becomes the ruling one Operating conditions in public inner-city local transport.

Nickel-cadmium batteries are particularly suitable as such batteries because they can be recharged quickly and because of their low internal resistance show only slight heating during charging and thus the phenomena mentioned above not triggered. Investigations have shown and were appropriately documented, that these batteries are up to 90% of their capacity within can be charged for about 30 minutes.

It has also been found that these batteries work normally without being damaged to become very heavily loaded, with currents that are a hundred times that Correspond to the nominal amperage (the nominal amperage in amperes results if the number of AmpAre hours of the battery is divided by 5). It should be noted, however, that these strong discharge currents are only drawn for about a minute to be allowed to. Conversely, these batteries are also able to generate charging currents in of the same order of magnitude for periods of a few tens of seconds, provided adequate regulation of the charging voltage is ensured. More about this is in the files of the Electrochemical Society Inc., which on the occasion of Cleveland Fall Meetings October 3-7, 1971.

The possibility of rapid partial charging by periods of discharge be replaced, is the prerequisite for a vehicle with electric operation, that is suitable for urban service. A vehicle that does this Type of batteries, and a correspondingly installed bus stop network open up the possibility that the vehicle, i.e. the bus, while stopped In a stop for passengers to get on or off, the energy is restored that it has used on the previous route.

Let us consider an example in which the omnibus is the same Has the same performance as a normal 0-bus. The one installed for the operation of the vehicle Motor power is usually 70 kW. A vehicle of this type takes at the However, starting up a higher power than the nominal power, e.g. 100 kW. she is required to accelerate the vehicle within 10 seconds.

During the journey to the next stop, a middle one becomes Power for exercise maintenance of an average of 25 kW consumed for one Driving time of around 25 seconds, i.e. for a few hundred meters. In the final phase the journey in which the vehicle is braked is usually provided that the kinetic energy is recovered and converted into electrical energy. Nevertheless, let us assume here that there is no recovery, but rather that the kinetic energy is converted into heat loss. Under these conditions is the energy consumed to travel a route ETot = Es + E Tot s m where E = total energy dead E = acceleration energy 5 E = average energy for the maintenance of exercise.

m Under the assumptions made, E = 100 x 10 + 25. 25 = 0.45 kWh.

3,600 3 * 600 This energy can easily be taken from one of the vehicle battery can be picked up and recharged at a stop. Assume that the Trans ~ port system voltage used 500 V and the available recharging time at a stop 14 sec long (i.e. that only one person gets on or off the bus quickly) and provided that there is an efficiency of 0.7 when recharging, then the charging current is about 320 A. If now the charging current is about 10 times as much should be as large as the rated current for one-hour charge, what - as experience show - as the ratio for a quick reload is completely sufficient, then it is enough a battery capacity of around 34 Ah installed in the vehicle.

The nickel-cadmium cells available as alkaline batteries have a nominal charge of 25 Wh per 3 kilograms of weight and 50 Wh per dm3 on. It is therefore a battery of approximately 650 for the present operating case kg weight necessary with a volume of about 0.32 m3. These values are for a vehicle whose curb weight is about 8 t is fully acceptable and the total weight the batteries and the motor system will not be much higher in this case than at a vehicle powered by a diesel engine.

It should also be emphasized that in this example calculation the installed Charging allowed about 10 to 15 trips without having to be recharged, like this that there is an extremely high reserve factor and a perfect one for the vehicle Mobility permitted in inner-city traffic. It is therefore not dependent on to go to the next stop for quick recharging, so that it is also possible to provide diversions in the route on a case-by-case basis, if this should become necessary for some reason. in the The example given has also not taken into account that the average Stop on a main line is usually of longer duration than assumed above so that a charge can be recovered at such a stop, which corresponds to the consumption for a route of several stop sequences.

From this it can be concluded that it is not necessary that Provide all stops with electrical supply connections for recharging must be. For example, you can stop at the stops that are only optional, skip the installation with supply connections. The stops that have such supply connections are expediently designed in such a way that that they do not require any special activity from the driver, so that the reloading happens automatically. This will be discussed in the explanation of the drawings to be received.

First of all, FIG. 1 is considered. On two cantilevered masts 2 is a stable, rigid electrically conductive rail 1 attached to one of the lines 10 is connected, this rail is so robust that it has a certain Can withstand impact from the pantograph 5 of the preferably vehicle 12. Your length is / is dimensioned so that, if necessary, several vehicles can be connected to it at the same time can be connected. The overall arrangement is expediently in one Parking bay next to the actual carriageway 0 If the overall system is also thus adapted to a tram system that may exist in the same city is that the height of the busbar 1 above the track and the voltage with correspond to the corresponding size of the road ban network, then in emergencies the vehicle 12 can also be supplied from the tram power network.

An electrically conductive plate 3 is inserted into the ceiling of the roadway, which is connected to the other pole of the line 10. This is usually earthed. On the roof of the vehicle 12 is a pantograph consisting of the rod 4 and the grinder 5 attached. The grinder 5 has a certain minimum width, in order to make it easier for the vehicle driver to drive under the busbar 1. That The present system is designed so that when the vehicle 12 enters the busbar 1 of the pantograph arm 4 is pressed down. Through a of this operated switch 8, a servomechanism 9 is triggered, the one Current collector 6 on the underside of the vehicle presses on the plate 3. The servo system 9 can be carried out electrically, hydraulically or pneumatically.

When leaving the stop, the aforementioned process takes place in the reverse order, whereby while driving under the busbar 1 there is an additional dwell time of the vehicle on the power supply circuit.

One takes care that immediately upon making contact with the grinder 5 on the busbar 1, the charging process is put into operation, then the Stop a loading time of maximum length available.

Since the dragging path length of the current collector 5 on the busbar 1 is very short compared to e.g. with tram operation and the busbar 1 can be made very robust, the system according to the invention enables the Realization of relatively large contact areas and higher Contact pressures. In this way, the contact resistance at the contact is sufficiently small that the already to be able to process the high currents mentioned.

The power supply line 10 is from the route of the vehicles 12 largely independent, it can e.g. be relocated with abbreviations, in particular wired underground. The achievable insulation values between the individual conductors with free wiring are considerably better than those with an O-bus line, because with the latter due to the carrying mechanism, especially on switches and crossings, certain transitional conductance values cannot be avoided.

Finally, it should be noted that the stops are several at the same time Lines can serve, whereby a transport network can be created that at a limited number of charging stations the vehicles extensive freedom of action leaves on the lines.

Fig. 3 shows the latter relationships in schematic form The solid lines represent the possible routes of the individual Vehicles represent, while the dashed lines are an image of the possible Line routing for the power supply of the individual stops by means of the lines 10 show. This line network has a control center 11 for the power supply tied together. But it is also possible to have several control centers for the power supply of the Network to be provided.

From Fig. 3 it can be seen that the supply network is completely different Can be guided as the routes of the vehicles, so that it is according to its own Needs, such as lowest costs, highest efficiency and something similar can be created. The only caveat lies in the location of the stops for which the aspects already mentioned are decisive are.

In other words, while the conventional transportation systems with electrical operation are based on a structure with meshes in the mobile network, So depend on the structure of given routes, the supply network is based in the transport system according to the present invention on a node structure, which allows the vehicles to adapt to traffic conditions without difficulty adapt It is also possible to create additional stops without further ado, which do not necessarily have to be included in the power supply. The system is therefore practically as flexible in inner-city traffic as one that diesel powered vehicles used.

Although basically a unipolar power supply network for the supply was enough, it is advantageous to use a bipolar one because it does the harmful effects of stray interference currents in the earth are avoided.

Although the system described above using the example of the public Local transport has been explained, it goes without saying that it applies to this application is not restricted. It turns around in equal measure and with innumerable benefits also in solutions that use rail-bound vehicles, such as the tram, the U-Bahn and the S-Bahn, with the necessary modifications, is its use too usable in public shipping with fixed stops or also in in-house transport systems, where electric carts, forklifts and the like Vehicles are used.

Claims (4)

Patent claims 1. Transport system with at least one battery-powered vehicle and stops, in particular for local public transport, characterized that in the vehicle (12) batteries of a charge capacity are used1 for one route enable multiple stop sequences and can be recharged quickly, that the reloading time is only a fraction of the driving time, and that for reloading of the batteries at least some of the stops have electrical supply connections (1, 3) and the vehicle with appropriate connecting means (5, 6) are provided. 2. Transport system according to claim 1, characterized in that as Batteries Nickel-cadmium batteries are used. 3. Transport system according to claim 1 or Z, characterized in that that the connecting means (5, 6) when the vehicle (12) drives into a stop automatically establish contact with the supply connections (1, 3). 4. Transport system according to claim 1, characterized in that the Connecting means consisting of a rod fastened to the vehicle (12) with it (4) with a current collector bracket (5) and one attached to the floor of the vehicle (12) Current collector roller (6) exist. 50 transport system according to claim 1, characterized in that the Supply connections in the bus stop from a statically rigid, at least a mast (2) or the like. Attached busbar (1) and one in the floor of the roadway electrically conductive plate (3) attached in the area under the busbar or like exist.