SU915178A1 - Method of dynamic braking of induction electric motor with open magnetic circuit of inductor - Google Patents

Description

The invention relates to electrical engineering, and more specifically to linear electric machines, and can be used for dynamic braking of various translational mechanisms.

There is a known method of dynamic braking of induction electric machines with an open magnetic circuit, according to which two phases are connected to the DC source, and the third does not flow around with a direct current I '] ·

The disadvantage of this method of braking is a decrease in the developed braking force due to the non-switched third phase.

The closest to the proposed technical solution is in its essence a method of dynamic braking of an induction electric machine ι with an open inductor magnetic circuit carrying a three-phase winding and a secondary element when

2

where the beginning of one Phase is connected to the end of the second phase, its end to the end of the third phase, and the beginnings of the second and third phases are connected to a DC source [2 ^

⁵ The disadvantage of this method of dynamic braking is that due to the manifestation of the longitudinal edge effect, the magnitude of the braking force differs significantly in size ¹⁰ not with an arbitrary choice of Phases as the first, second and third.

The purpose of the invention is to increase the braking force.

⁵ The object is achieved in that to one pole of the DC source connected top phase placed but symmetric about the transverse axis of the inductor and to the other pole - the beginning of phase-shifted relative to the transverse axis in the direction of movement vtorichnogo- element.

3 915178

The drawing shows a three-phase

induction electric machine ·

with an open magnetic circuit.

The device contains an inductor 1 with a three-phase winding, the working body 2 (secondary element), moving with speed V from left to right. The beginning and end of the first phase winding are marked with clips ΙΗ, 1K. The axis of the winding of this phase is offset relative to the axis of the first inductor 1 against the direction of movement of the working fluid 2. The beginning and end of the second phase winding are marked with clips 2H, 2K, and the third phase winding - clips ZN, LC. The axis of the second phase winding is offset relative to the axis of the inductor 1 in the direction of movement of the working fluid 2, and the axis of the third phase winding coincides with the axis of the inductor 1. End 1K ₂ o

the first Phase winding is connected to the end of the third phase winding.

The beginning of the 1H of the first Phase winding is connected to the end of the 2K of the second phase winding. The beginning of the 2H and the beginning of the EZ of the second and third phase windings are connected respectively to the minus and plus of the DC source.

The process of dynamic braking proceeds as follows. _thirty

When you turn on the DC source in phase windings induk-. torus 1 will pass the current. This current excites a stationary magnetic field. When moving the operating box body 2 there is induced an electromotive force which causes current to flow in the working fluid 2. Interaction working body 2 with currents magnetic field ₄₀ nym DC inductor 1 results in a braking force.

The force generated by an induction electric machine with an open magnetic circuit in the dynamic braking mode is defined as the sum of two components

^p- g ^{= P} about ^{+ P} PKE

where Ro is the main effort

^P ~ SCE ^{force P} P ° D ^Aulnay kraevo- ⁵⁰ th effect.

The main force F is generated _on the electromagnetic field existing in the area of the inductor 1. The value etogr force does not depend on successive phase windings ³⁵ NOSTA connection between soboy'i for a given value of DC remains unchanged.

The force of the longitudinal edge effect ^ ^ is due to the electromagnetic field outside the inductor 1 '. The appearance of this field is due to the presence of magnetic conductivity outside the inductor 1 and the magnetizing force acting at the edges of the inductor 1.

For this machine, the magnetic conductivity outside the inductor 1 is constant. Consequently, the magnitude of the electromagnetic field outside the inductor 1 and the magnitude of the force ^ cdpolnostyo determined by the magnetizing force at the edges of the inductor 1. The magnitude of the magnetizing force at the edges of the inductor 1 for a given DC value depends only the direction of the current in the coil sides of the phase windings, i.e. the sequence of the connection of the phase windings together.

The magnetizing force at the edges of the inductor 1 when using the circuit shown in the drawing, is equal to its maximum value. Therefore, the force of the longitudinal edge effect 1 ^ _cd for this scheme is also maximal. Maximum will be the total force P ^.

Claims (1)

Claim The method of dynamic braking of an induction electric machine with an open inductor magnetic circuit carrying a three-phase winding and a secondary element in which the beginning of one phase is connected to the end of the second phase, its end to the end of the third phase, and the beginning of the second and third phases is connected to a DC source, characterized in that in order to increase the braking force, a pole of a phase located symmetrically relative to the transverse axis in the direction of movement of the secondary is connected to one pole of the DC source an item.