SU1660110A1 - Linear induction motor - Google Patents

Description

The invention relates to electrical engineering, to a linear inductor motor used for transport on a magnetic suspension. The goal is to improve the mass-abilities and

reduction of power consumption. The device consists of a primary part in the form of a U-shaped magnetic circuit with an active pole 1 with an armature winding 4 and a passive pole 2 connected by a yoke 3 with an excitation winding 5. The yoke and the secondary part 6 are made in the form of a comb. The base of the comb of the secondary part is located in the zone of the passive pole, and the base of the yoke comb is located in the zone of the active pole, while it consists of three teeth, each of which has an excitation winding coil. Extreme coils are connected to the regulators of the magnetic suspension, and the middle to the switch. A positive effect is achieved by improving the distribution of the magnetic flux and reducing scattering. 2 ~

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with:

The invention relates to electrical engineering and can be used for thrust and lifting of the crew on an electromagnetic suspension.

The purpose of the invention is to expand the scope by applying the engine for transport on a magnetic suspension, reducing the weight and size parameters and power consumption, improving the roll stabilization.

Figure 1 and 2 shows the motor, transverse and longitudinal sections; fig.Z the same general view; figure 4 - picture of the longitudinal magnetic field of the electric motor; in Fig.5 is a diagram of the connection of the suspension regulators to the coils of the excitation winding.

The electric motor consists of a primary part, which is made in the form of a U-shaped magnetic circuit with an active laminated pole 1 and a passive pole 2. Both

poles are attached to the yoke 3. Nz active pole is placed winding 4 anchors. On the yoke laid winding 5 excitation. The yoke and the secondary part 6 are made of a comb (fig. 3), with the base of the comb of the secondary part located in the zone of the passive pole, and the base of the comb of the yoke - in the zone of the active pole (figure 2). The yoke consists of three teeth (figure 2), on each of which are located the excitation winding coils. Two extreme coils of the excitation winding 031 and 083 are connected to the regulators of the magnetic suspension ARP1 and ARP2 (figure 5), and the middle coil ОВ2 is connected to the switch B which is controlled by regulators ARP 1 and ARP2. The suspension regulators ARP1 and ARP2 and switch 3 are connected to the onboard power supply source PI. The tip of the passive pole 2 has non-magnetic inserts 7 _about which

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laid symmetrically with respect to the excitation coils 5 (figure 2).

The operation of the motor will consider the example of a longitudinal picture (figure 4) and a transverse (figure 1) magnetic field. As can be seen from figure 1, the magnetic flux F _in , created by the winding 5 of excitation, closes across the electric motor, and the magnetic flux F _i , created by the winding 4 of the armature, closes in the longitudinal direction. Since the secondary part 6 is lengthwise composed of discretely installed ferromagnetic elements (comb teeth), the excitation magnetic flux F _{in is} modulated (distribution curve of the magnetic flux F _in in figure 4). The modulated magnetic flux F _in the excitation can be represented as a sum of a constant and a variable of its components. Depending on how much current to power the armature winding, the electric motor can operate in DC mode or in synchronous mode. In the first case, the thrust force arises due to the interaction of the armature current with the modulated excitation magnetic flux F _in length (Fig. 4). Switching 'current in the armature winding is carried out by a contactless switch (valve mode).

In the second case the thrust force is generated by the interaction of the running magnetic field F _to the armature (4 shows a first harmonic component of this field) with the modulated in the longitudinal direction of the magnetic excitation field F _in. In this case, the thrust force is proportional to the values of the excitation magnetic flux of the PV and the anchor Φ _i . as well as the sine of the load angle Θ. The lifting force, according to Maxwell's formula, is proportional to the square of the magnetic induction in the air gap and the cross-sectional area of the poles in the air gap zone.

To improve the stabilization of the motor roll, it is necessary that the lifting forces generated by the passive and active poles are approximately equal. Since the magnetic flux of excitation in the air gap is common for the passive and active poles, this can be achieved by choosing the cross section (width) of the poles.

In accordance with Maxwell’s equation, the lifting force is

where f is the magnetic flux;

5 - pole section;

/ * o - magnetic constant.

The lifting forces generated separately active (EPA) and passive (P _P p) poles Е _P P = EPA.

For an electric motor, these efforts are defined by the following expressions

_with _ F 'Kya ^na 2-Za-Do'

_from _ f ι4η

^{Ρηη 1}

where K _rp and K _va are the coefficients of buckling of the magnetic field, depending on the geometry of the poles and the size of the air gap.

Za-la ‘Lg2’ P, “Zn-2bn 'R'T, where bn is the width of the passive pole:

B _a is the width of the active pole;

L2 is the width of the tooth of the comb of the secondary section;

p is the number of pairs of anchor poles; t - pole division of the armature (fig.Z). Substituting the values of Za and 5 _P in the expressions for Epa and Epp and equating them, get an expression that defines the ratio between the width of the passive and active poles

The control by tagnazh is carried out by regulating the current in each excitation coil (in the extreme coils OV1 and OVZ of FIG. 5),

To exclude the passage of the magnetic flux of the excitation created by one of the excitation coils to the neighboring section, the tip of the passive pole 2 has non-magnetic inserts 7 (Figures 2, 3). When increased requirements are imposed on the electric motor for mechanical rigidity, these inserts are made of titanium or non-magnetic steel and are rigidly connected to the sections of the passive pole. The width of the non-magnetic inserts is equal to the size of the air gap between the primary and secondary parts of the electric motor. Reducing the width reduces the effectiveness of the solution, and increasing it worsens the picture of the magnetic field in the gap under the passive pole, reduces the effective cross section of the pole.

Since the excitation winding of the electric motor is divided into three parts, and only two coils ОВ1 and ОВЗ are connected to the regulators of the magnetic suspension, the total power and, accordingly, the weight of the suspension regulators is reduced by 1/3. At the same time, the middle coil ОВ2 (figure 5) creates a constant lifting force equal to about 1/3 of the total lifting force generated by the electric motor. For emergency inclusion of the middle coil (for example, when

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drastically reducing the air gap

between the primary and secondary parts) is a switch B (for example, contactless), controlled by one or two

regulators suspension ARP 1, ARP2.

Thus, the effectiveness of the solution is to reduce the width of the magnetic circuit in the air gap zone, which helps to improve the roll stabilization, reduce the mass of the primary part and the suspension controllers by about 1520% (the additional mass of the middle coil switch is much less than the mass of the magnetic suspension controller) under-15 weights about 1/3,

Claims (3)

Claim 1. A linear inductor motor containing a primary part in the form of a U-shaped magnetic circuit with an active 20 pole on which the armature winding is placed, a passive pole and a yoke on which the excitation winding is placed, and a passive secondary part separated from it by an air gap The form of discrete 25 ferromagnetic elements, characterized in that, with the aim of expanding the scope of application by applying the engine for transport on a magnetic suspension, reducing the weight and size indicators 30 and consumed power, the yoke of the primary magnetic core is made in the form comb with a base adjacent to the active pole, and three teeth, each of which contains an excitation winding coil, and ferromagnetic elements 5 of the secondary part are also made in the form of a comb with a base connecting discrete ferromagnetic elements and located in the zone of the passive pole. 2. The motor according to claim 1, characterized in that it is equipped with two non-magnetic inserts placed between the passive poles of the primary magnetic core in the zone adjacent to the air gap, while the width of the inserts is equal to the size of the air gap between the primary and secondary parts. 3. The electric motor according to claims 1 and 2, which is based on the fact that, in order to improve roll stabilization, the width of the passive and active poles is determined from the ratio where L _p , b _a is the width of the passive and active poles; L2 is the width of the tooth of the comb of the secondary section; Кпп, Кьа ~ the coefficients of buckling of the magnetic field in the gap for the passive and active poles, respectively; g-pole division. 1660110 5 1660110 5