RU34464U1 - Vehicle AC traction device - Google Patents

Description

DEVICE FOR DRIVING AC VEHICLES

The utility model relates to the field of electrical machines and can be used in a traction asynchronous electric drive with linear single-phase motors.

A vehicle alternating current traction device is known which comprises two or more induction capacitor motors, each of which includes two field windings. These windings are located on the moving part of the installation in one row along the vehicle at a distance of pole division from each other. In addition, the device contains a non-winding secondary element located stationary, as well as switches with contacts and connected in each motor between the beginning and the end of the field windings, a chain of series-connected resistor and capacitor (AS USSR No. 1818260, 60 L 13/00 , N 02 K 41/025, publ. 30.05.93, Bull. No. 20).

This device allows you to create traction, braking and levitation forces.

However, it has several disadvantages, namely:

- relatively low value of efficiency especially in the start-brake operation modes due to large energy losses in the resistors;

- low value of the power factor of the device in the running mode;

- a large number of contacts and switches in power circuits; as well as significant masses and dimensions of starting resistors and capacitors and the associated mass-dimensional indicators.

   60 L 1zSh

H 02 to 41/025

The first one includes at least two field windings located in one row along the transnational means at a distance of pole division one relative to the other, and a stationary non-winding secondary element. In addition, the device is equipped with two inverters, a four-quadrant converter and a control unit with their interconnections. The first excitation windings of the motors are combined with the beginnings and ends that are connected to the outputs of one inverter, the second excitation windings of the motors are also combined with the beginnings and ends that are connected to the outputs of another inverter (Utility certificate No. 11513, 60 L 13/00, Н 02 К 41/025, publ. 16.10.99, Bull. No. 10) - prototype. This device traction on the vehicle’s alternating current allows you to increase the energy efficiency of the device when creating traction and levitation forces and reduce its weight and size indicators.

However, the possibility of increasing traction and levitation forces, and hence the speed and reliability of the crew’s suspension above the track, is limited by the capabilities of the magnetic system of the winding-free element.

The objective of the utility model is to increase the efficiency and reliability of the device by increasing the traction and levitation forces by improving its design.

The problem is solved by means of an alternating current traction device of a vehicle containing two asynchronous linear motors, each including at least two field windings arranged in a row along the vehicle at a distance of pole division one relative to the other, and a stationary non-winding secondary element , a power source whose outputs are connected to the inputs of the control unit, the first three outputs of which are connected respectively to the inputs of the four-quadrant reobrazovatelya, fourth and fifth outputs of the control unit connected to the first

the inputs of autonomous inverters, the output of the four-quadrant converter is connected to the second inputs of the first and second inverters, the beginnings and ends of the first windings of induction motors are connected to the outputs of the first inverter, and the beginnings and ends of the second windings of the motors are connected to the outputs of the second inverter equipped with a plate of ferromagnetic material, rigidly fixed in the vehicle’s crew housing, along it above the engine excitation windings.

The introduction of a ferromagnetic plate in the design of the device allows you to increase the magnitude of the working magnetic flux of the on-board electromagnets of the field windings and thereby increase the value of the traction force and levitation force of the device.

The foregoing allows us to conclude that the proposed technical solution meets the criterion of novelty, as well as that there is a causal relationship between the totality of essential features and the achieved technical result.

In FIG. 1 shows a block diagram of the proposed device.

Figure 2 shows a block diagram of a control unit.

The traction device on the alternating current of the vehicle (Fig. 1) contains two asynchronous linear motors, each including, as primary elements, two field windings 1, 2 and 3, 4 located in a row along the vehicle 5 at a distance pole division one relative to the other, and a stationary non-winding secondary element 6. In addition, the device contains a power source 7, the outputs of which 8 and 9 are connected to the inputs of the control unit 10, the first three outputs of which 11,12,13 are connected respectively with the inputs of the four-square converter 14. The fourth and fifth outputs 15 and 16 of the control unit 10 are connected to the first inputs of the same name of the autonomous inverters 17 and 18. The output 19 of the four-quadrant converter 14 is connected to the second inputs 20 and 21 of the first 17 and

second 18 inverters. The beginnings (indicated by dots) and the ends of the nerve windings of 1 and 3 induction motors are connected to the outputs 22 and 23 of the nerve inverter 17, respectively. The beginnings (indicated by dots) and the ends of the second windings of 2 and 4 motors are connected to the outputs 24 and 25 of the second inverter 18. In addition, the device equipped with a plate 26 of ferromagnetic material, rigidly fixed in the hull of the vehicle crew 5, along it above the motor excitation windings 1,2,3,4.

The control unit 10 (figure 2) contains a phase meter 27, the inputs of which are the inputs 8.9 of the control unit 10. For the first time, the two outputs of the phasemeter 27 are the first two outputs 11,12 of the control unit 10, intended for connection with the inputs of the same name of the quadrant converter 14 (Fig. 1). The output 28 of the phase meter 27 (figure 2) is connected to the input of the pulse-width modulator 29, the output of which is the output 13 of the control unit 10, designed to connect to the third input of the quadrant converter 14 (figure 1). In addition, the control unit 10 (figure 2) contains a sinusoidal voltage generator 30, the output of which 31 is connected to the inputs 32 and 33 of the phase shifters 34 and 35. The output 36 of the phase shifter 34 is connected to the input of the phase shifting element 37, the output 38 of the latter is connected to the input of the pulse shaper 39, the output of which is the fourth output 15 of the control unit 10, designed to be connected to the first input of the first inverter 17 (Fig. 1). The output 40 (FIG. 2) of the phase shifter 35 is connected to the input of the phase shifting element 41, the output 42 of the latter is connected to the input of the pulse shaper 43, the output of which is the fifth output 16 of the control unit 10, designed to be connected to the first input of the second inverter 18.

The four-quadrant converter circuit 14 can be used from the book “Non-educational devices of electric trains with asynchronous traction motors / Soludonov A.M., Inkov Yu.M., Kovalivker G.N., Litovchenko V.V .; Ed. A.M.Solodunova.- Riga: Zinatne, 1991.- 351 p.

The phasometer 27 and the pulse-width modulator 29 are designed to set the operating mode of the four-quadrant Converter 14 (figure 1). A sinusoidal voltage generator 30 (FIG. 2) generates clock pulses for the control unit 10. Phase shifters 34 and 35, together with phase shifting devices 37 and 41 produce the required control angle for autonomous inverters 17 and 18 (figure 2). The pulse shapers 39 and 43 (figure 2) create control pulses for power elements of autonomous inverters 17 and 18.

With the number of motors and greater than two, for example, with n 4, two more pairs of field windings appear in the device. In this case, the windings of the third and fourth motors, respectively, are interconnected with the outputs 22, 23 and 24, 25 of the inverters 17, 18 (Fig. 1) similarly to the second pair of coils 3 and 4 of the second motor.

Field windings 1, 2, 3, 4 are made of a superconducting material, for example, Y-Ba-Cu-O.

The non-winding secondary element 6 is made of a non-magnetic material, for example, aluminum. The magnetic permeability of the material of the winding-free secondary element 6 / /, where / Id is the magnetic permeability of the vacuum; the specific conductivity cg of the material of element 6 is nonzero.

Another material for the non-winding secondary element 6 are alloys of aluminum, copper and other metal having a low electrical resistivity.

The ferromagnetic plate 26 has a magnetic permeability // / and cg 0. Moreover, the specific conductivity cg of the ferro plate 26 to reduce eddy current losses in it has a significantly lower value than the specific conductivity cg of the secondary element 6. The device operates as follows. Steady state mode. Inverters 17 and 18 (figure 1) under the influence of the control unit 10 generate voltages that change in phase in time. In this case, current flows through windings 1 and 3 from the beginning to the end, and in windings 2 and 4 from end to beginning. As a result, the magnetic field created by windings 1 and 3 is directed in the opposite direction to the magnetic field created by windings 2 and 4, Currents in windings 1, 2, 3, 4 they create around them a pulsating magnetic flux that changes in time, which is equivalent to two identical magnetic fluxes of constant magnitude, but traveling in different directions with the same speed V (direct and reverse field). The interaction of these traveling magnetic fields in the secondary element 6 gives rise to a levitation force (from interaction with a direct field) and traction force (from interaction with a reverse field). At zero speed, the traction force is zero, and the levitation force provides suspension of the moving part of the device, the mode of the start (acceleration). Inverters 17 and 18 under the influence of the control unit 10 create voltages shifted in time relative to each other so that the currents in adjacent field windings are phase shifted by 90 el. degrees, and the current in the subsequent winding should lag behind the current in the previous winding, namely: the current in winding 2 is behind the current in winding 1, the current in winding 3 is behind the current in winding 2, and the current in winding 4 is behind the current in winding 3. As a result, a traveling magnetic field is created, which induces eddy currents in the secondary element 6. The interaction of the magnetic field of the field windings 1, 2, 3, 4 with the magnetic field of the eddy currents of the winding-free secondary element 6 causes, firstly, traction.

forcing, the moving part of the device will accelerate in the direction indicated by the arrow in FIG. Secondly, this interaction of magnetic fields causes the appearance of a levitation force, pushing the moving part of the device from the fixed part

Braking mode.

Inverters 17 and 18 under the action of the signals of the control unit 10 create voltages that are shifted in time relative to each other so that the currents in the adjacent field windings are phase shifted by 90 el. degrees, and the current in the subsequent winding should be ahead of the current in the previous winding, namely: the current in winding 2 is ahead of the current in winding 1, the current in winding 3 is ahead of the current in winding 2, the current in winding 4 is ahead of the current in winding 3. As a result, around These field windings produce a traveling magnetic field directed in the opposite direction to the magnetic field at start-up. The interaction of the magnetic fields of the field windings and the magnetic field of the eddy currents in the secondary element 6 causes two forces: traction, which makes the moving part of the installation slow down, or move in the opposite direction to the arrow in FIG. 1; and levitation force pushing the movable part of the device from the fixed part.

Due to the presence of the ferromagnetic plate 26, the flux linkage of the magnetic field created by the currents of the field windings 1,2,3,4 increases with the stationary part of the vehicle, as a result of which the emf values increase and eddy currents induced in the non-winding secondary element 6, which leads to increased interaction of the traveling magnetic fields of the field windings with the magnetic field from the eddy currents in element 6, that is, to an increase in traction (braking) and levitation forces.

to the accuracy of laying the track structure and, accordingly, to reduce the cost of its installation and operation.

The increase in traction allows you to increase the speed of the crew on the highway and, therefore, increase the throughput of this system.

While maintaining a constant suspension height, the presence of a ferromagnetic plate can reduce the amount of current required in the on-board electromagnets, and therefore increase the efficiency system by reducing energy losses in the elements of the internal and external power supply system of the vehicle.

The additional mass introduced by the ferromagnetic plate is compensated, according to the theoretical calculations, by the gain in lift that appears as a result of their use.

Claims (1)

Vehicle alternating current traction device containing two asynchronous linear motors, each including at least two field windings arranged in a row along the vehicle at a distance of pole division one relative to the other, and a stationary non-winding secondary element located, power source the outputs of which are connected to the inputs of the control unit, the first three outputs of which are connected respectively to the inputs of the four-quadrant converter, the fourth and fifth output The control unit s are connected to the first inputs of the autonomous inverters, the output of the four-quadrant converter is connected to the second inputs of the first and second inverters, the beginnings and ends of the first windings of induction motors are connected to the outputs of the first inverter, and the beginnings and ends of the second windings of the motors are connected to the outputs of the second inverter, characterized in that it is equipped with a plate of ferromagnetic material, rigidly fixed in the vehicle’s crew housing, along it above the motor excitation windings.