RU2067350C1 - Linear induction motor - Google Patents

Abstract

FIELD: automatic control and robotics. SUBSTANCE: linear induction motor has inductor built up of core 1 incorporating yoke and teeth carrying three-phase winding coils; each coil has N equivalent sections (N = 2, 3... ); each tooth of core 1 carries one coil; it has also secondary member 3 on ball supports 4 and switching device 5 connecting coil section 2 with voltage supply. Switching device 5 is connected to voltage supply through knife-switch 6. EFFECT: provision for discrete control of secondary member step. 10 dwg

Description

 The invention relates to the field of electrical engineering, and more specifically to a linear electric drive and is intended for use in robotics and machine drive.

 Known linear asynchronous electric drive (ed. St. USSR N 790080 class N 02 K 41 \ 02, 1980), containing an inductor consisting of individual cores with windings connected by a switching device to a voltage source. Limited functionality The disadvantage of this drive.

 The closest in technical essence to the claimed one is a linear asynchronous electric drive (ed. St. USSR N 1755352 class N 02 K 43 \ 025), containing an inductor consisting of a core including yoke and teeth, with multiphase winding coils, each of which covers one core tooth, an electrically conductive secondary element and a switching device connecting the winding coils to a voltage source, with at least the first five winding coils connected by the switching device to the voltage source, They form the initial row, the winding coils of the initial row form a straight line until the middle of the row, and the opposite sequence of phases after the middle. To take a step of the secondary element, the switching device disconnects the last coil of the winding of the initial row from the voltage source, for electromagnetic fixation of the secondary element, the switching device disconnects the first coil of the initial row and connects the winding coil next to the last of the initial row to the voltage source, creating a new row , the winding coils of which form up to the middle of the row a straight line, and after the middle the opposite order of phases. The secondary element is placed on supports mounted for rotation. We selected this electric drive as a prototype.

 This electric drive provides stepwise translational movement of the secondary element with a step of one tooth division, while not allowing the regulation of the step size.

 This is a disadvantage of the prototype.

 The purpose of the invention is the discrete control of the step size of the secondary element.

 The goal is achieved in that in a linear asynchronous electric drive containing an inductor consisting of a core including yoke and teeth with three-phase winding coils, an electrically conductive secondary element mounted on supports mounted for rotation, and a switching device connecting the winding coils to a voltage source according to the invention, on each tooth of the core of the inductor there is a winding coil made of N sections equivalent to each other (N 2,3), with at least the first five coils of quipment connected switching device to a voltage source to form an initial row of an initial set of the winding coil to form a series of mid-line, and after the middle of the row opposite phase order. This makes it possible for the secondary element to make step-by-step movements with the value S L \ N of tooth divisions, where L is the number of sections of the last coil of the initial row disconnected from the voltage source (L 1, 2, N).

When the drive is operating to take the step of the secondary element, the switching device disconnects at least one section of the last coil of the initial row, and at least the last coil of the inductor of the initial row from the voltage source, while the step of the secondary element is at least 1 \ N of tooth divisions, and at least one tooth division, and the step value S of the secondary element is calculated by the formula:
SL \ N, serrated divisions;
where L is the number of sections of the last coil of the initial row disconnected from the voltage source (L 1, 2 N), after the secondary element moves one tooth division, for its more reliable electromagnetic fixation by the switching device, the first coil of the initial row winding is disconnected from the voltage source and the last coil of the initial row and the coil of the coil following it are connected to the voltage source, and a new row is created, the winding coils of which form up to the middle of the row ryamoy, and after the middle - opposite phase order.

 The location on each tooth of the core of the inductor of the coil of the winding made of N sections equivalent to each other (N 2, 3), this feature determines the novelty of the technical solution.

 We did not find any similar solutions in the field of linear asynchronous electric drives and in related fields of technology in patent searches. This allows us to make a judgment that the inventive electric drive has significant differences.

 In FIG. 1 shows a general view of a linear asynchronous electric drive (front view); FIG. 2 depicts (schematically) a fragment of an inductor of a linear asynchronous electric drive (front view); FIG. 3 order of connecting sections of the coils of the three-phase winding of the inductor to the phases of the voltage source before completing the step of the secondary element (initial row); FIG. 4 the same at the beginning of the first step of the secondary element by half of the tooth division; FIG. 5 the same at the end of the first step of the second element by half of the tooth division; FIG. 6 the same at the beginning of the second step of the secondary element by half of the tooth division; FIG. 7 the same at the end of the second step of the secondary element by half of the tooth division; FIG. 8 - the procedure for connecting sections of the coils of the three-phase winding of the inductor to the phases of the voltage source after moving the secondary element to one tooth division (new row); FIG. 9, the procedure for connecting sections of the coils of a three-phase winding of the inductor to the phases of the voltage source at the beginning of the step of the secondary element by one tooth division; FIG. 10 fragment of the connection diagram of the conclusions of the sections of the coils of the inductor winding by means of a switching device to a voltage source.

 The linear asynchronous electric drive (Fig. 1) contains an inductor consisting of a core 1, comprising a yoke and teeth, with three-phase winding coils consisting of sections 2, an electrically conductive secondary element 3, supported by ball bearings 4. A switching device 5 connects sections 2 of the coils to voltage source through the circuit breaker 6. O, A, B, C designations of the conclusions of the voltage source.

 In FIG. 2 shows (schematically) a fragment of an inductor of a linear asynchronous electric drive, namely, the arrangement of sections 2 of the coils of a three-phase winding on the teeth of the core 1.

 In FIG. Figure 3 shows the connection of sections 2 of the coils of the three-phase winding of the inductor to the phases of the voltage source until the step of the secondary element 3 (its electromagnetic fixation) is completed. The forces F1 and F2 acting on the secondary element 3 are indicated by arrows. A, B, C designate the phases of the sections of the 2 coils of the inductor winding connected to a voltage source. The remaining notation is the same as in FIG. 1.

 FIG. 4 depicts the same as FIG. 3, but when one of the sections 2 (in this case the lower one) of the last coil of the inductor of the initial row is switched off, the moment of the start of the first step of the secondary element 3 by half of the tooth division.

 FIG. 5 depicts the same as FIG. 4, but at the end of the first step of the secondary element 3 by half of the tooth division, its electromagnetic fixation.

 FIG. 6 depicts the same as FIG. 5, but with the last coil of the initial row disconnected from the voltage source, the moment of the beginning of the second step of the secondary element 3 by half of the tooth division.

 FIG. 7 depicts the same as FIG. 6, but at the end of the second step of the secondary element 3 by half of the tooth division, the electromagnetic fixation of the secondary element 3.

 FIG. 8 depicts the order of connecting sections 2 of the coils of the three-phase inductor winding to the phases of the voltage source after the secondary element 3 moves one tooth division (a new series of groups of inductor winding coils) electromagnetic fixation of the secondary element 3.

 FIG. 9 shows the connection of sections 2 of the coils of the three-phase winding of the inductor to the phases of the voltage source at the beginning of the step of the secondary element 3 by one tooth division, i.e. when the last coil of the inductor of the initial row is disconnected from the voltage source.

 FIG. 10 shows a fragment of a circuit for connecting sections 2 of inductor winding coils by means of a switching device 5 to a voltage source. The contacts of the switching device 5 are indicated by the positions 7 42. O, A, B, C are the designations of the terminals of the voltage source.

 Consider the operation of this linear asynchronous electric drive.

Depicted in FIG. 3 10 electric drive, where N 2 sections (each coil contains two sections 2) allows you to make the secondary element 3 steps of size:
S 1 \ 2 tooth division;
S 1 tooth division;
when one section 2 of the last coil of the winding of the initial row and both sections 2 are disconnected, i.e. the entire last coil of the winding of the initial row, respectively.

 Prior to completing the step of the secondary element 3 (Fig. 3) by the switching device 5, the first five coils of the winding of the electric inductor are connected to the voltage source, forming the initial row. In this case, the contacts 7, 10, 14, 17, 21, 24, 26, 29, 31, 34 (Fig. 10) of the switching device 5 are closed. All other contacts are open. The coils of the initial row, consisting of sections 2, form up to the middle of the row a direct sequence of phases, and after the middle the opposite: A, A; B, B; C, C; B, B; A, A (Figs. 3 and 10). Oncoming magnetic fields are generated, excited by currents flowing through the systems of sections 2 of the coil of the inductor winding, containing five sections 2: A, A; B, B; From left to right and A, A; B, B; From right to left. Running towards each other, magnetic fields intersect the electrically conductive secondary element 3 and induce electromotive forces in it, causing eddy currents to flow. When magnetic fields interact with eddy currents, mechanical counter-directed forces F1 and F2 are created, acting on the secondary element 3 (Fig. 3). These efforts balance each other and hold the secondary element 3 in its original position.

; В,В; С и справа налево: А; В,В; С (фиг. 5).To complete the first step of the secondary element 3 by half the tooth division, the switching device 5 disconnects from the voltage source one of the sections 2 of the last coil of the initial row of the inductor winding, for example, the lower one (Fig. 4). This opens the contact 31 of the switching device 5 (Fig. 10). The contacts 7, 10, 14, 17, 21, 24, 26, 29, 34 remain closed. All other contacts of the switching device 5 are open. The symmetry of oncoming magnetic fields is broken, because from left to right (Fig. 4) a traveling magnetic field is excited by currents flowing through a system of coils consisting of sections 2 containing five sections 2: A, A; B, B; C, and a magnetic field running towards the first (from right to left) is created by currents flowing through a system that includes only four sections 2: A; B, B; C. Thus, a magnetic field running from right to left is asymmetric and has an “elliptical” character. Running towards the magnetic field intersect the secondary element 3 and induce electromotive forces in it, causing the eddy currents to flow in the secondary element 3. When the traveling magnetic fields interact with the eddy currents, counter-directed mechanical forces F1 and F2 are created (Fig. 4). In this case, the force F1 will be greater than the force F2, and the secondary element 3 will begin to move from left to right under the influence of the difference of these forces. This movement will continue until counter-directed efforts become equal in magnitude. The balance of effort F1 and F2 occurs at the completion of the first step of the secondary element 3 by half of the tooth division, while the fields running towards each other will have the same "elliptical" character, that is, from left to right: $\genfrac{}{}{0ex}{}{\text{1}}{\text{2}}$ A

; B, B; C and from right to left: A; B, B; C (Fig. 5).

,

; В,В; С, а магнитное поле, бегущее навстречу первому (справа налево), создается токами, протекающими по системе катушек, включающей лишь три секции 2: В,В; С. Таким образом, магнитное поле, бегущее справа налево, является несимметричным и имеет более "эллиптический" характер, чем магнитное поле, бегущее слева направо. Бегущие навстречу магнитные поля индуктора пересекают вторичный элемент 3 и наводят в нем электродвижущие силы, вызывающие протекание вихревых токов во вторичном элементе 3. При взаимодействии бегущих полей с вихревыми токами возникают встречно направленные механические усилия F1 и F2 (фиг. 6). При этом усилие F1 будет больше усилия F2, и вторичный элемент 3 под действием разности этих усилий начнет двигаться слева направо. Это движение будет продолжаться до тех пор, пока встречно направленные усилия не станут равными по величине. Равновесие усилий F1 и F2 наступает по завершению второго шага вторичного элемента 3 на половину зубцового деления, при этом поля, бегущие навстречу друг другу, будут иметь одинаковый "эллиптический" характер, т.е. слева направо: В,В; С и справа налево: В,В; С (фиг. 7). Суммарное перемещение вторичного элемента 3 за два шага, описанных выше, составило одно зубцовое деление.In order to complete the second step of the secondary element 3 by half of the tooth division, the switching device 5 disconnects from the voltage source the remaining (upper) section 2 of the last coil of the initial row, i.e. now the entire last coil of the initial row is disconnected from the voltage source (Fig. 6). In this case, the contact 34 opens, the contacts 7, 10, 14, 17, 21, 24, 26, 29 remain closed, and all the other contacts of the switching device 5 are open (Fig. 10). The symmetry of the counter-running magnetic fields is broken, since from left to right (Fig. 6) the traveling magnetic field is excited by currents flowing through a system of coils consisting of sections 2 containing five sections:

,

; B, B; C, and a magnetic field running towards the first (from right to left) is created by currents flowing through the coil system, which includes only three sections 2: B, B; C. Thus, a magnetic field running from right to left is asymmetric and has a more “elliptical” character than a magnetic field running from left to right. The magnetic fields of the inductor running towards them intersect the secondary element 3 and induce electromotive forces in it, causing eddy currents to flow in the secondary element 3. When the traveling fields interact with the eddy currents, counter-directed mechanical forces F1 and F2 arise (Fig. 6). In this case, the force F1 will be greater than the force F2, and the secondary element 3 will begin to move from left to right under the influence of the difference of these forces. This movement will continue until counter-directed efforts become equal in magnitude. The balance of forces F1 and F2 occurs at the completion of the second step of the secondary element 3 by half of the tooth division, while the fields running towards each other will have the same “elliptical” character, i.e. from left to right: B, B; C and from right to left: B, B; C (Fig. 7). The total displacement of the secondary element 3 in the two steps described above amounted to one tooth division.

 For stable electromagnetic fixation of the secondary element 3 in a new position, the first coil of the initial row is disconnected from the voltage source and the last coil of the initial row and the coil of the inductor winding following it are connected to the voltage source (Fig. 8). A new row of coils of the inductor winding is formed, in structure and properties similar to the original row, but shifted to the right by one tooth division. The procedure for connecting sections of 2 coils of the inductor winding of the new series is as follows: A, A; B, B; C, C; B, B; A, A (Fig. 8). To obtain a new series of coils of the inductor winding, open the contacts 7, 10, 14, 17, 21, 24, 26, 29 and close the contacts 13, 16, 20, 23, 27, 30, 32, 35, 37, 40 of the switching device 5, other contacts remain open (Fig. 10).

 To complete the first step of the secondary element 3 by one tooth division from the initial position, disconnect from the voltage source using a switching device 5 the last coil of the initial row of coils of the inductor winding (Fig. 9). The contacts 31 and 34 are opened, the contacts 7, 10, 14, 17, 21, 24, 26, 29 are closed, all other contacts of the switching device 5 are open (Fig. 10). The symmetry of counter-running magnetic fields is broken, since from left to right (Fig. 9) the traveling magnetic field is excited by currents flowing through the coil system of the inductor winding, consisting of sections 2, containing five sections 2: A, A; B, B; C, and a magnetic field running towards the first (from right to left) is created by currents flowing through a system of coils containing three sections 2: B, B; C. Thus, a magnetic field running from right to left is asymmetric and has an “elliptical” character. Running towards the magnetic fields intersect the secondary element 3 and induce electromotive forces in it, causing eddy currents to flow in the secondary element 3. When traveling magnetic fields interact with eddy currents, counter-directed mechanical forces F1 and F2 are created. In this case, the force F1 will be greater than the force F2, and the secondary element 3 will begin to move from left to right under the influence of the difference of these forces. This movement will continue until counter-directed efforts become equal in magnitude. The balance of forces F1 and F2 occurs at the completion of the step of the secondary element 3 by one tooth division, while the fields running towards each other will have the same "elliptical" character, i.e. from left to right: B, B; C and from right to left: B, B; FROM.

 For stable electromagnetic fixation of the secondary element 3 in a new position after completing a step by one tooth division, a new row of inductor winding coils is formed (Fig. 8), which is described above (the sequence of steps is exactly the same as after completing the second step of the secondary element 3 by half tooth division). In this case, we will have symmetrical magnetic fields running towards each other, intersecting the secondary element 3 and inducing electromotive forces in it, causing eddy currents to flow in the secondary element 3. Mechanical forces F1 and F2 are created when these eddy currents interact with traveling magnetic fields (Fig. 8), directed in the opposite direction and balancing each other. These efforts fix the secondary element 3 in a new position. Etc.

 You can control the inclusion of the contacts of the switching device 5 using a computer.

 Compared to the prototype, the functionality of the electric drive has been expanded: discrete regulation of the step size of the secondary element has been achieved. YYY2 YYY4 YYY6 YYY8

Claims (1)

 A linear asynchronous electric drive containing an inductor consisting of a core including a yoke and teeth with three-phase coil coils, an electrically conductive secondary element mounted on supports mounted for rotation, and a switching device configured to simultaneously connect to a voltage source to fix the armature at least at least five phase coils of the winding, forming along the longitudinal axis of the inductor an initial row in which, until its middle, is straight, and after the middle, the opposite a row of phase rotation, moreover, to take the step of the secondary element, with the possibility of disconnecting the last coil of the row, and for its electromagnetic fixation, with the possibility of disconnecting the first coil of the row and connecting the coil following the last coil of the initial row with the formation of a new row with the same phase sequence, as the initial row, characterized in that on each tooth of the core of the inductor the coil is made of N sections equivalent to each other, where N = 2,3.

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