DE2412221A1 - Differential fluid electrodynamic magnetic hover transport - with right angled figure eight shaped secondary coils parallel to primary coil planes - Google Patents

Abstract

The principle of the system is the attainment of zero-fluid operation with the primary coil utilisation of normal fluid operation, so as to achieve the simplest possible configuration of track and vehicle layout. The coil axes run horizontally, and the secondary coils may be mounted on the vertical interior of the track longitudinal supports, with an overall height of 80 cm. The magnetic support and guiding system requires a low iron content, and is operated by inductive effect on a secondary coil system by a primary energising coil system. The coils in the latter are mounted in the form of a figure 8 with roughly right-angles corners, and the planes of primary and secondary coils are parallel. The short-circuited couls may be half-overlapped, to prevent oscillations in supporting energy - or one-third overlapped if there are three coils involved. Aluminium semiconductors may be used in individual coils for suppression of eddying effects.

Description

"Supra-eight differential flow method, a new variant of the electrodynamic Levitation technology "1. Introduction It is recommended to use electrodynamic support systems as Train zero flow method, since the normal flow technique leads to braking forces that are of the order of magnitude of the aerodynamic resistance and are therefore too oversized Installations for the drive and lead to high energy consumption. Of this Powell and Danby were guided by over-flexion, whose design proposal (the Zero flow method) a reduction in braking forces from around 5% to around 1% of the Vehicle weight allows.

The idea of the zero-flow method on which the physical principle is based is based on Revhner and partially experimentally reconstructed. n however to convert it into a convincing arrangement of vehicle and roadway elements be extraordinarily difficult. The reasons for this are that it protrudes in several levels Lane shape, the flying arrangement of secondary and excitation coils (Fig. 1).

If you move the excitation device for the primary field to the outside and the secondary part to the inside, a zero-flow arrangement also arises if there is counteract the two subfields.

The advantages of this modified zero flow arrangement (Fig. 2) lie especially in the simplified carriageway element, which will be an aluminum flat conductor can. However, this must also be attached in a flying arrangement. Disadvantageous is further that on the vehicle now double the number of magnets increased electrical Flooding must be installed so that the weight and cooling capacity of the vehicle structure affect. In addition, the simultaneous use of a zero flow method for carrying and that of a synchronous long-stator propulsion vehicle and roadway configuration further complicate and therefore prohibit themselves.

2. The differential flux method with load-bearing forces in the direction of the coil plane The method described below is physical with the zero flow arrangements related, but differs in terms of the flow management and the winding design fundamental.

The main idea behind the proposal to be described here is with the Primary coil effort of the normal flux method the effect of the zero flux method to achieve the simplest possible lane and vehicle configuration to achieve.

It should be less drastic here if the tracking element not designed as a homogeneous aluminum rail, but in the form of pronounced coils must be, provided that this avoids complicated designs of the roadway and vehicle can be. An additional advantage is a conductor arrangement with pronounced coils the more favorable material utilization. Since the secondary conductor system is a Short-circuit winding with coil voltages in the range of 1 volt exists here no isolation problem.

The simplicity of the geometrical arrangement of the supra-eight differential flow method is essentially determined by the fact that the coil axes run horizontally. she are thus rotated by 900 compared to the previously known support systems.

The secondary coils are so z. B. on the vertical inside of the To arrange fatjrbahn longitudinals. Their total height is in the range of approx. 80 cm (Picture 3a).

The mode of operation of the support arrangement is based on the induction effect moving magnetic fields and has the characteristics typical for this. Takes one assumes that - as shown in Figure 3b - the hatched area of the coil surface and with it represents the zone of the induction component By running in the coil axis, a voltage is induced in the coil at a sufficiently high speed vx, which leads to rivers. Coil currents and magnetic field of the excitation coil result Forces in the three main directions perpendicular to each other. Of which are Fx the braking forces, F lateral forces and Fz the load-bearing forces. Requirement for the y The creation of the coil currents is a deflection in the z-direction. With a vertical shift t creates a resulting voltage in the secondary coil, which is shaped into an 8, which causes the electricity. The direction of the current, which determines the direction of the force is determined so that in accordance with Lentz's rule the effect of the primary field is weakened by the current. From this it follows z. B.

the direction of the current in the middle parts of the coil. With the current Ix in the middle branch and the y-component of the magnetic induction follows for each unit of length of the conductor the load capacity Fz = 2 Ix By.

This makes it clear that here, in contrast to those previously described Arrangements the normal component of the coil induction used to generate forces will. The generation of tension and the effect of force are based on the same induction component.

For an example, the curves of the load-bearing capacity F z and are shown in Figure 4 the braking force Fx, based on F the load capacity value, at very high speed applied. Fx cycles at a fraction of the vehicle's top speed a maximum value in order to then decrease approximately inversely proportional to the speed Vx. The use of more conductor material results in the upper speed range a reduction in braking force and shifts the increase in load capacity to lower speeds.

The dependence of the load-bearing capacity on the deflection is constant Speed shown in Figure 5. Fo and 0 are the values at rest, in the vehicle weight is compensated without dynamic influences.

3. Execution of excitation coils and secondary winding For superconductor technology the task is to build an excitation coil that is spaced 20 -. 25 cm from the winding plane an induction component of acting in the coil axis about 1 T.

Inductions of this size are also used with the normal flow method at a similar distance provided.

Not just the conductors lying in the center axis of the excitation coil of the secondary coil, the outer return conductors also contribute to the formation of the load capacity. Figure 6 shows the course of the load capacity and braking force as a function of the ratio the coil width b / b. The reference value is the respective sp force with the same coil widths chosen. It makes sense to choose values around 1.5 to 2 for b / b.

The conductors are made of thin aluminum partial conductors to suppress eddy currents perform whose oxidation layer has an insulating effect. You are flexible with it and can be laid and cast in the specified form.

Through the symmetrically overlapping one sketched in Figures 3a and 3b Arrangement of the short-circuited individual coils is achieved that fluctuations in the load capacity be avoided. If 2 coils overlap, the amount of overlap is the same as that half spool width; if 3 coils are involved in the overlap, this amounts to overlap dimension 1/3 of the Spulem ^ Tei-e.

4. The lateral forces - coil plane inclined to the vertical For the lateral guidance of the vehicle, stabilizing forces Fy are required, whereby it seems permissible to use the forces acting in both partial tracks in their To take advantage of Sunde and not to require the stabilization of a partial track.

The support arrangement described so far proves to be in terms of Forces acting in the y-direction as stable in this sense, d. H. in the event of a shift restoring forces occur in the y-direction. However, the amount is lateral Restoring forces too low to be sufficient against all disturbing forces that occur Ensure leadership.

to increase the side forces by a factor of about 10, the is sufficient Application of some additional coils. However, it does not seem necessary to provide additional To apply tracking devices. The few necessary lateral guide coils can be attached in such a way that they make a positive contribution to the secondary ladder system to induce the tensions.

Your induction B forms with the total current 21 of the Tragz x coils the lateral force. For this purpose, the coil axis of the lateral guide coils must be aligned vertically will. Figure 7 shows the arrangement of a double coil in common cryostat can be accommodated. Since the number of lateral guide coils is at most half that When the number of reels is reached, the additional effort appears to be manageable.

It turns out that when the lateral guide coils are used, both F and F increase in approximately the same way, so x that the quotient Fx / F z practically remains constant.

As the calculation also shows, the natural frequency fe decreases in comparison Vertical oscillation .gen due to the superposition of one of the deflection t less than proportional current component. The auxiliary coil with a vertical coil axis can also can be viewed as a means of influencing the spring characteristic.

Another option without additional coils is the side executives To generate, consists in the winding-0 plane by an angle of about 30 against to incline the vertical (see Fig. 8).

The strong dependency of the force F z (and their components Fz and Fy) from the distance between the coil planes z y. At a Shifting the vehicle towards the secondary coil increases the restoring forces Fy. They bring about y (albeit less damped) return to the central plane. In order to achieve a resulting side force of about 0.4 times with such a configuration Vehicle weight with a deflection of 2. Reaching 3 cm seems like an angle oC of little more than 300 is sufficient.

5, The question of the drive Far more than that of the electromagnetic one Electrodynamic levitation technology demands a support system that is not tied to a vehicle Drive that does not have the relatively large clearance between the vehicle and the track limited by the coupling conditions of the short stator motor.

An additional equipment of the vehicle with superconducting coils, exclusively for the formation of tunneling, but encounters difficulties for several reasons, so that the urgent desire to use the support coils at the same time for the formation of propulsion to use remains.

As a consideration illustrated in Figure 9 shows, this induces magnetic field of a coil of the traveling field winding of the long stator in the 8-shaped Coil of the support system no tension, since the two parts of the magnetic Cancel the field in the upper and lower halves for the creation of the clamping mechanism; the both coils are decoupled. This applies to the entire windings as well as to Single coils, including the shape of a single-line meander winding is. The only condition is that there must be a symmetrical arrangement with respect to the vertical position is given, it may be concluded from this that the load-bearing and propulsion winding can be arranged in close proximity to one another in the same guideway bed.

In the case of a coil plane inclined by the angle az, it has an effect favorable from the fact that with a somewhat increased magnetic flux, a smaller current load is required for the formation of thrust compared to a vertical winding plane.

Claims (5)

5 c h u t z a n s p r ü c h e 1); Magnetic carrying and transporting method, which is mainly low in iron is carried out and by inductive influencing of a secondary coil system acts on a primary excitation coil system without contact, characterized in that that the secondary coils are arranged in the form of a figure eight with an approximately rectangular shape and the planes of the primary and secondary coils are parallel. 2) Magnetic carrying and guiding method according to 1), characterized in that that to avoid fluctuations in the load capacity, the short-circuited coils are half be arranged overlapped. If there are 3 coils involved in the overlap, that is Overlap dimension 1/3 of the spool width, etc. 3) Magnetic carrying and guiding method according to 1) and 2), characterized in that that the individual coils to suppress eddy current influences from a variety thin sub-conductors that are interlaced (stranded wire) z. B. consist of aluminum, the be soldered or welded to create a closed circuit. 4) Magnetic carrying and guiding method according to 1) to 3), characterized in that that forces for lateral guidance either by additional exciters rotated by 900 coil or by pivoting the exciter and secondary coil level by approximately 300 can be achieved. 5) Magnetic carrying and guiding procedure according to 1) to 4), thereby characterized that the propulsion winding (traveling wave winding of a synchronous long stator drive) the support winding is arranged closely adjacent and yet inductively decoupled and the excitation coils take on the carrying, guiding and propulsion functions.