GB2357270A

GB2357270A - Rapid transit system for compact electric vehicles

Info

Publication number: GB2357270A
Application number: GB9925554A
Authority: GB
Inventors: Michael Godwin; Haider Al-Abadi
Original assignee: AL ABADI HAIDER
Current assignee: AL ABADI HAIDER
Priority date: 1999-10-29
Filing date: 1999-10-29
Publication date: 2001-06-20
Anticipated expiration: 2019-10-29
Also published as: GB9925554D0; GB2357270B

Abstract

The transit system comprises a self propelled electric vehicle 13 modified to run on a rail system 10 via flanged wheels attached to the vehicle. A pair of permanent magnets 12 fitted beneath the vehicle sequentially couple magnetically with sections 29 of stator 11 located alongside the rails. Each stator section 29 is energised at the appropriate frequency via electronically switch inverter in response to sensors (24 fig 3) to externally drive the vehicle and comprises a single phase winding 22 associated with an assembly of alternating inner and outer (wrt the winding sides) pole structures 18,19.

Description

2357270 Means for providing Rapid Transit for Compact Electric Vehicles

(Syncho-rail) This invention relates generally to all non-polluting urban and city centre rapid transit systems, more specifically to a low cost distributed linear synchronous motor using permanent magnets as one of the elements to provide the thrust for moving compact vehicles at high speed.

Air pollution in modern cities caused by emissions from vehicles burning fossil fuels is becoming a serious problem. Government authorities are under pressure to exploit non-polluting energy sources, e.g. electricity, to replace the internal combustion engine in transport systems necessary for city centres and the urban environment. The gap. between the present day electric vehicle and its automotive counterpart in terms of performance, i.e. speed and range, remains as challenge for new technology to lessen and resolve.

According to the present invention there is provided the means by which a mass produced electric vehicle is permitted to engage a rail system via flanged wheels attached to the vehicle. Permanent magnets fitted beneath the vehicle then couple magnetically with the fixed stator located alongside or between the rails. Energising the stator with appropriate current, voltage and frequency will then cause the vehicle to accelerate to a substantially high speed without absorbing any power from the vehicles' own power drive system.

The track is formed of two parallel steel rails of suitable gauge alongside or between which a low cost design of linear synchronous motor stator is located. This track assembly which may be many kilometres long is hereinafter known as "Synchro-rail".

The key technical features of "Synchro-rail" are:

1. A low cost, very compact, efficient design of the "Synchro-rail" stator using a single coil single phase winding with'claw type pole pieces.

2. The use of at least two flanged wheels on the vehicle to provide a substantially accurate location for the permanent magnet assembly with respect to the "Synchro-rail" stator.

3. The use of electronic switches and sensors as the means for locally energising the section of "Synchro-rail" directly beneath the vehicle and its magnet frame, and thus ensure control at all times.

4. The use of a third/fourth tyred wheel/wheels located towards the rear of the vehicle so that once the vehicle has mounted the "Synchro-rail" and the front pneumatic tyred wheels are out of contact with the track the vehicle 2 weight is substantially taken by the front flanged wheels and this rear tyred wheel/wheels. The purpose is to limit the normal vehicle suspension to ensure the magnetic gap alignment is satisfactory and the vehicle is safe in case of punctured rear pneumatic tyre.

5. To use of this third/fourth tyred wheel to provide both the necessary power to charge the vehicle's batteries during its journey and a suitable very low speed independent drive if required to enable the synchronous motor to get into step and accelerate the vehicle in the case of it becoming stationary on the "Synchro-rail".

6. The vehicle once travelling on the "Synchro-rail" is entirely under the control of the linear motor and thus immune from any action the driver/passenger may choose to make. With the vehicies'front wheels lifted clear steering and power train are inoperable as are the rear brakes.

7. Once moving the vehicle is entirely under the control of "Synchrorail", its acceleration and speed being determined exclusively by the supply frequency. Thus all vehicles are forced to travel at the same speed and safety is assured by the nature of any synchronous motor i.e. high electrical and magnetic stiffness. Exploiting this unique property mean safe travel at high density and high flow rates, possible easily exceeding a single lane of existing motorway.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing in which:

Figure 1 shows the "Synchro-rail" system with a modified electric vehicle, Figure 2 shows a section of the synchronous 'Claw motor used in the "Synchro-rail"; Figure 3 shows the electronic switching arrangement for the "Synchro- rail".

Referring to the drawing the "Synchro-rail" comprises two parallel steel rails between which a linear synchronous motor stator 11 is located. Mounted on the "Synchro-rail" is a modified electric vehicle 13 fitted with a permanent magnet frame 12, two flanged front steel wheels 14 and one/two rear solid tyred wheels 15.

As the modified electric vehicle 13 moves on to the narrow gauge steel rails 10, the front flanged steel wheels 14 lifts the pneumatic tyred front wheels 16 clear of the track. At the same time the magnets 12 attached to the underside of the car drop into place. Between the rails is a "Claw" type linear synchronous motor stator 11. The stator is divided into sections and as the high recoil permanent magnets 21 attached to the underside of vehicle engage the stator section they activate an electronic position sensor 24 which connects that section to an inverter supply 23 by means of electronic 3 switches 25 as shown in fig 3. With the stator is energised, thrust will be produced as the magnets couple with the flux emanating from the stator. The purpose of using oneltwo rear solid tyred wheels 15 is to limit the normal vehicle rear suspension to ensure a magnetic gap alignment is satisfactory and the vehicle is safe in case of punctured rear pneumatic tyrel 7.

The "Claw" type linear synchronous motor stator 11 is assembled by winding a single phase single coil 22 on the laminated inner claws 19 and then inserting the laminated outer claws 18 round the coil 22 to complete the magnetic circuit as shown in fig 2.

The speed of the vehicle is synchronised to the frequency of the sinusoidal supply connected to a stator section 29 by means of the electronic switches which is closed looped to the position sensors 24 as shown in Fig 3. The function of the control circuit 26 which dictates the sinusoidal frequency of the electronic switches 25 is to synchronise this frequency to the synchronising signal 27. If the control circuit 26 fails to synchronise the sinusoidal supply frequency connected to a stator section 29, and hence the speed of the vehicle, to the synchronising signal 27 for say 100 cm of the vehicle travel distance then it activates a change in the synchronising signal 27 to its own so that other vehicles travelling behind will have the same speed as the one at front. This is very important to avoid accidents if one vehicle due to a malfunction can not achieve the top speed of 110 km/hr for any length of the track.

The "ClaW'type linear synchronous motor as described is substantially capable of providing power in the range of 20-25 kw which is sufficient to overcome friction and air resistance encountered by a typical compact vehicle travelling at 110 km/hr.

4

Claims

CLAIMS What we claim is:

1 - Two parallel steel rails of any length alongside or between which are contiguous sections of low cost synchronous linear motor stator the flux from which if suitably energised reacts with a permanent magnet frame located beneath a modified mass produced electric passenger vehicle to cause the vehicle, provided it has mounted the power rail hereinafter known as "Synchro-rail", to travel along the rails at a speed determined exclusively by the frequency of the current applied to the linear motor stator.

2. A "Synchro-rail" as claimed in Claim 1 wherein a contiguous section of linear motor stator comprises a single coil of wire around which is placed Claw'type pole pieces.

3. A "Synchro-rail" as claimed in Claim 1 or Claim 2 wherein the means of ensuring alignment of the permanent magnet frame located beneath the modified electric vehicle is achieved by using flanged wheels attached to the vehicle which accurately locate on to the parallel steel rails.

4. A "Synchro-rail" as claimed in Claim 1 or Claim 2 or Claim 3 which is only permitted to become energised in the presence of the permanent magnet frame located beneath the modified electric vehicle.

5. A "Synch ro-rai I" as claimed in Claim 3 wherein the means of supporting the modified electric vehicle on the "Synchro-rail" is by flanged wheels and solid tyred wheels such that the vehicle's normal pneumatic tyres are substantially clear of the "Synchro-rail" track when the modified electric vehicle mounts the "Synchro-rail" to begin a journey.

6. A"Synchro-rail" as claimed in Claim 5 wherein the means of charging the modified electric vehicle's batteries during its journey on the "synchrorail" is provided by a generator connected to one of the wheels in contact with the "synchro-rail".

7. A "synchro-rail" as claimed in Claim 6 wherein the means of slowly moving the modified electric vehicle should it become stationary on the "Synchro rail" is by switching the charging generator to become a motor that then can move the modified electric vehicle to enable it to become synchronous with the frequency of supply to the "Synchro-rail" stator.

8. A "Synchro-rail" substantially as described herein with reference to Fig 1, Fig 2 and Fig 3 accompanying these claims.