CN109192617B - Electromagnetic controllable attraction force is as alternating current contactor of twin coil structure of counter-force - Google Patents
Electromagnetic controllable attraction force is as alternating current contactor of twin coil structure of counter-force Download PDFInfo
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- CN109192617B CN109192617B CN201811104601.1A CN201811104601A CN109192617B CN 109192617 B CN109192617 B CN 109192617B CN 201811104601 A CN201811104601 A CN 201811104601A CN 109192617 B CN109192617 B CN 109192617B
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 125
- 230000003068 static effect Effects 0.000 claims abstract description 56
- 230000005284 excitation Effects 0.000 claims description 12
- 238000001514 detection method Methods 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 4
- 230000000694 effects Effects 0.000 claims description 3
- 239000003302 ferromagnetic material Substances 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000005291 magnetic effect Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H50/00—Details of electromagnetic relays
- H01H50/44—Magnetic coils or windings
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H50/00—Details of electromagnetic relays
- H01H50/16—Magnetic circuit arrangements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H50/00—Details of electromagnetic relays
- H01H50/54—Contact arrangements
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Relay Circuits (AREA)
- Electromagnets (AREA)
Abstract
The invention provides an alternating current contactor with an electromagnetic controllable suction force as a counter force and a double-coil structure, which comprises an electric control system, a contact system, a movable iron core switching-on end, a movable iron core switching-off end, a static iron core, a switching-on coil and a switching-off coil, wherein the movable iron core is provided with a movable iron core; the contact system is arranged at the closing end of the movable iron core; the movable iron core switching-on end is connected with the movable iron core switching-off end through a push rod; the static iron core is positioned between the closing end and the opening end of the movable iron core, a closing coil and an opening coil are arranged at the static iron core, the closing coil attracts towards the closing end of the movable iron core, and the opening coil attracts towards the opening end of the movable iron core; when the switch is switched on, the switch-on coil is electrified and the switch-off coil is powered off, so that the switch-on end of the movable iron core is attracted with the static iron core, and the switch-off end of the movable iron core is pushed away from the static iron core by the push rod; when the switch is switched off, the switch-on coil is powered off and the switch-off coil is powered on, so that the switch-off end of the movable iron core is attracted with the static iron core, and the switch-on end of the movable iron core is pushed away from the static iron core by the push rod; the invention has the advantages of no arc, stability and long service life.
Description
Technical Field
The invention relates to the technical field of power equipment, in particular to an alternating current contactor with a double-coil structure and electromagnetic controllable attraction as counter force.
Background
In the prior art, part of alternating current contactors are designed to be respectively connected with a pair of unidirectional thyristors in parallel or connected with a bidirectional thyristor on a three-phase contact to realize micro-arc operation of the contactor, but the scheme has higher requirements on overvoltage and overcurrent bearing capacity of power electronic elements, and if no reliable protection measures are adopted, the power electronic elements can be damaged due to heating loss of the power electronic elements to cause circuit faults.
In the design of the existing alternating current contactor, a permanent magnet mechanism is used for realizing all functions of a transmission wiring or an electromagnetic mechanism by combining a permanent magnet and an existing electromagnet; because of the existence of the permanent magnet, the opening counter force of the contactor is the permanent magnet magnetic force and the spring counter force which is obviously much larger than the counter force of the electromagnetic contactor; the permanent magnet provides a stable magnetic field, which is an advantage, but it is a disadvantage in the normal state that the contactor cannot be separated without electricity, which may cause accidents at the time of next operation or sudden power supply.
In combination with the above problems, the invention adopts the AC contactor with the double-coil structure, skillfully uses the electromagnetic controllable attraction as the counter force, and solves the problem that the performance of the contactor is influenced when the counter force spring is too large or too small. Therefore, the problem of repeated bouncing when the contact is disconnected or switched on is well solved. And the main loop is disconnected near the current zero crossing under the control of the singlechip, so that micro-arc breaking is effectively realized. And a low-voltage holding loop is added, so that on the premise of ensuring the power-on holding, the resources can be saved, and the problems of long-time power-on heating of the coil and the like are reduced.
Disclosure of Invention
The invention provides an alternating current contactor with a double-coil structure and electromagnetic controllable attraction as counter force, which has the advantages of no arc, stability and long service life.
The invention adopts the following technical scheme.
An alternating current contactor with a double-coil structure and electromagnetic controllable suction as counter force is used for switching-off and switching-on operations of a three-phase alternating current circuit, and comprises an electric control system, a contact system, a movable iron core switching-on end, a movable iron core switching-off end, a static iron core, a switching-on coil and a switching-off coil; the contact system is arranged at the closing end of the movable iron core; the movable iron core switching-on end is connected with the movable iron core switching-off end through a push rod by a fastener comprising a push rod retainer ring and a bolt; the movable iron core switching-on end and the push rod are integrated; the static iron core is positioned between the closing end and the opening end of the movable iron core, a closing coil and an opening coil are arranged at the static iron core, the closing coil attracts towards the closing end of the movable iron core, and the opening coil attracts towards the opening end of the movable iron core; when the switch is switched on, the switch-on coil is electrified and the switch-off coil is powered off, so that the switch-on end of the movable iron core is attracted with the static iron core, and the switch-off end of the movable iron core is pushed away from the static iron core by the push rod; when the switch is switched off, the switch-on coil is powered off and the switch-off coil is powered on, so that the switch-off end of the movable iron core is attracted with the static iron core, and the switch-on end of the movable iron core is pushed away from the static iron core by the push rod.
A counter-force spring is arranged between the switching-on end of the movable iron core and the static iron core; when the opening coil and the closing coil are both powered off, the reaction spring keeps the opening end of the movable iron core and the static iron core in a separated state; the contact system comprises a static contact and a moving contact; the moving contact is arranged at the closing end of the moving iron core; when the switch is switched on, the switch-on end of the movable iron core drives the movable contact to move towards the fixed contact and be connected.
The static iron core is fixed at the shell of the alternating current contactor; the static iron core is of an E-shaped combined structure; the closing coil is wound at the closing coil framework and is fixed by a closing coil retainer ring; the opening coil is wound on the opening coil framework and is fixed by an opening coil retainer ring.
The electric control system comprises a single chip microcomputer, a power supply module, an intelligent control module and a circuit detection module; the intelligent control module comprises a strong excitation module and a low-voltage maintaining control module.
The moving contact comprises an A-phase main contact, a B-phase main contact and a C-phase main contact; the B-phase main contact is arranged between the A-phase main contact and the C-phase main contact; and when the switch is switched on, the A-phase main contact and the C-phase main contact are firstly jointed with the static contact to enable the A-phase main contact and the C-phase main contact to be switched on, and then the B-phase main contact is jointed with the static contact to enable the B-phase main contact to be switched on.
The circuit detection module detects the zero crossing point of the first-phase load current of the three-phase alternating-current circuit, determines a delay time length T by taking the zero crossing point as a reference, and after the delay time length T, the electric control system is switched off by the alternating-current contactor; the closing coil is powered off and the opening coil is powered on through the strong excitation module, the moving contact is driven to be separated from the static contact at a preset speed, three phases of alternating current are quickly disconnected near a load current zero crossing point, and micro-arc opening is achieved.
The working voltage of the closing coil is a pulsating direct-current voltage obtained by rectifying a single phase of alternating-current voltage by an electric control system; and the electric control system selects an optimal closing phase angle during closing according to the pulsating direct current voltage so that the alternating current contactor finishes closing suction action at the optimal initial closing phase angle.
After the switching-on coil performs switching-on operation under the strong excitation effect of the strong excitation module, the electric control system enables the switching-on coil to be connected with a low-voltage direct-current power supply under the control of the single chip microcomputer, and the alternating-current contactor enters a low-voltage direct-current holding state.
And in the low-voltage direct current holding state, the low-voltage direct current power supply connected to the closing coil is a direct current power supply of DC 9V.
The movable iron core switching-on end and the push rod are of an integrally formed structure; the movable iron core switching-on end, the push rod and the movable iron core switching-off end are all parts of the movable iron core; the movable iron core and the static iron core are both formed by ferromagnetic materials without remanence.
The invention adopts the AC contactor with the double-coil structure, skillfully takes the electromagnetic controllable attraction as the counter force, and solves the problem that the performance of the contactor is influenced when the counter force spring is too large or too small. Therefore, the problem of repeated bouncing when the contact is disconnected or switched on is well solved. And the main loop is disconnected near the current zero crossing under the control of the singlechip, so that micro-arc breaking is effectively realized. And a low-voltage holding loop is added, so that on the premise of ensuring the power-on holding, the resources can be saved, and the problems of long-time power-on heating of the coil and the like are reduced.
The invention solves the problem that large electric arc is generated when the AC contactor is disconnected and the problem that the conventional AC contactor only relies on spring reaction force for opening, and improves the performance index of the product.
The invention can enter into a low-voltage direct current holding state after closing, thereby realizing reliable, energy-saving and silent holding operation.
In the switching-on action of the AC contactor, different switching-on initial phase angles are selected, and the contactor has completely different pull-in dynamic processes; the invention can select different optimal closing phase angles according to different power voltages, so that the contactor finishes the suction process under the optimal initial closing phase angle, thereby effectively avoiding the non-closing phenomenon of the contactor or avoiding serious iron core impact and contact bounce.
Drawings
The invention is described in further detail below with reference to the following figures and detailed description:
FIG. 1 is a schematic of the present invention;
FIG. 2 is a partial schematic view of the contact system of the present invention;
FIG. 3 is a schematic diagram of the control principle of the present invention;
in the figure: 1-a movable iron core opening end; 2-bolt; 3-a push rod; 4-opening coil retainer ring; 5-opening coil; 6-opening the brake coil framework; 7-closing coil framework; 8-closing coil; 9-a stationary core; 10-moving core switching-on end; 11-a stationary contact; 12-a moving contact; 13-a contact spring; 14-a counter force spring; 15-closing coil retainer ring;
a phase 101-A main contact; a 102-B phase main contact; a 103-C phase main contact;
300-push rod retainer ring.
Detailed Description
As shown in fig. 1-3, an ac contactor with a dual-coil structure with electromagnetically controllable attraction as a counter force is used for switching on and off a three-phase ac circuit, and includes an electric control system, a contact system, a moving core switching-on end 10, a moving core switching-off end 1, a stationary core 9, a switching-on coil, and a switching-off coil; the contact system is arranged at the closing end of the movable iron core; the movable iron core switching-on end and the movable iron core switching-off end are connected through a push rod 3 by a fastener comprising a push rod retainer ring 300 and a bolt 2; the movable iron core switching-on end 10 and the push rod are integrated; the static iron core is positioned between the closing end and the opening end of the movable iron core, a closing coil 8 and an opening coil 5 are arranged at the static iron core, the closing coil attracting direction faces the closing end of the movable iron core, and the opening coil attracting direction faces the opening end of the movable iron core; when the switch is switched on, the switch-on coil is electrified and the switch-off coil is powered off, so that the switch-on end of the movable iron core is attracted with the static iron core, and the switch-off end of the movable iron core is pushed away from the static iron core by the push rod; when the switch is switched off, the switch-on coil is powered off and the switch-off coil is powered on, so that the switch-off end of the movable iron core is attracted with the static iron core, and the switch-on end of the movable iron core is pushed away from the static iron core by the push rod.
A counter-force spring 14 is arranged between the switching-on end of the movable iron core and the static iron core; when the opening coil and the closing coil are both powered off, the reaction spring keeps the opening end of the movable iron core and the static iron core in a separated state; the contact system comprises a static contact 11 and a moving contact 12; the moving contact is arranged at the closing end of the moving iron core; when the switch is switched on, the switch-on end of the movable iron core drives the movable contact to move towards the fixed contact and be connected.
The static iron core is fixed at the shell of the alternating current contactor; the static iron core is of an E-shaped combined structure; the closing coil is wound at the closing coil framework 7 and is fixed by a closing coil retainer ring 15; the opening coil is wound on the opening coil framework 6 and is fixed by the opening coil retainer ring 4.
The electric control system comprises a single chip microcomputer, a power supply module, an intelligent control module and a circuit detection module; the intelligent control module comprises a strong excitation module and a low-voltage maintaining control module.
The moving contact comprises an A-phase main contact 101, a B-phase main contact 102 and a C-phase main contact 103; the B-phase main contact is arranged between the A-phase main contact and the C-phase main contact; and when the switch is switched on, the A-phase main contact and the C-phase main contact are firstly jointed with the static contact to enable the A-phase main contact and the C-phase main contact to be switched on, and then the B-phase main contact is jointed with the static contact to enable the B-phase main contact to be switched on.
The circuit detection module detects the zero crossing point of the first-phase load current of the three-phase alternating-current circuit, determines a delay time length T by taking the zero crossing point as a reference, and after the delay time length T, the electric control system is switched off by the alternating-current contactor; the closing coil is powered off and the opening coil is powered on through the strong excitation module, the moving contact is driven to be separated from the static contact at a preset speed, three phases of alternating current are quickly disconnected near a load current zero crossing point, and micro-arc opening is achieved.
The working voltage of the closing coil is a pulsating direct-current voltage obtained by rectifying a single phase of alternating-current voltage by an electric control system; and the electric control system selects an optimal closing phase angle during closing according to the pulsating direct current voltage so that the alternating current contactor finishes closing suction action at the optimal initial closing phase angle.
After the switching-on coil performs switching-on operation under the strong excitation effect of the strong excitation module, the electric control system enables the switching-on coil to be connected with a low-voltage direct-current power supply under the control of the single chip microcomputer, and the alternating-current contactor enters a low-voltage direct-current holding state.
And in the low-voltage direct current holding state, the low-voltage direct current power supply connected to the closing coil is a direct current power supply of DC 9V.
The movable iron core switching-on end and the push rod are of an integrally formed structure; the movable iron core switching-on end, the push rod and the movable iron core switching-off end are all parts of the movable iron core; the movable iron core and the static iron core are both formed by ferromagnetic materials without remanence.
In this example, the push rod is connected with the opening end of the movable iron core by a bolt 2; the moving contact is supported on the moving core switching-on end 10 by a contact spring 13.
Claims (5)
1. The utility model provides an alternating current contactor of twin coil structure of controllable suction of electromagnetism as counter-force for to the separating brake of three-phase alternating current circuit, closing operation, its characterized in that: the alternating current contactor comprises an electric control system, a contact system, a movable iron core switching-on end (10), a movable iron core switching-off end (1), a static iron core (9), a switching-on coil (8) and a switching-off coil (5); the contact system is arranged at the closing end of the movable iron core; the movable iron core switching-on end is connected with the movable iron core switching-off end through a push rod (3) by a fastener comprising a push rod retainer ring (300) and a bolt (2); the movable iron core switching-on end (10) and the push rod are integrated; the static iron core is positioned between the closing end and the opening end of the movable iron core, a closing coil (8) and an opening coil (5) are arranged at the static iron core, the closing coil attracts towards the closing end of the movable iron core, and the opening coil attracts towards the opening end of the movable iron core; when the switch is switched on, the switch-on coil is electrified and the switch-off coil is powered off, so that the switch-on end of the movable iron core is attracted with the static iron core, and the switch-off end of the movable iron core is pushed away from the static iron core by the push rod; when the switch is switched off, the switch-on coil is powered off and the switch-off coil is powered on, so that the switch-off end of the movable iron core is attracted with the static iron core, and the switch-on end of the movable iron core is pushed away from the static iron core by the push rod;
a counterforce spring (14) is arranged between the switching-on end of the movable iron core and the static iron core; when the opening coil and the closing coil are both powered off, the reaction spring keeps the opening end of the movable iron core and the static iron core in a separated state; the contact system comprises a static contact (11) and a moving contact (12); the moving contact is arranged at the closing end of the moving iron core; when the switch is switched on, the switch-on end of the movable iron core drives the movable contact to move towards the fixed contact and be connected;
the static iron core is fixed at the shell of the alternating current contactor; the static iron core is of an E-shaped combined structure; the closing coil is wound at the closing coil framework (7) and is fixed by a closing coil retainer ring (15); the opening coil is wound on the opening coil framework (6) and is fixed by an opening coil retainer ring (4);
the electric control system comprises a single chip microcomputer, a power supply module, an intelligent control module and a circuit detection module; the intelligent control module comprises a strong excitation module and a low-voltage maintaining control module;
the movable iron core switching-on end and the push rod are of an integrally formed structure; the movable iron core switching-on end, the push rod and the movable iron core switching-off end are all parts of the movable iron core; the movable iron core and the static iron core are both formed by ferromagnetic materials without remanence;
the push rod is arranged at the symmetrical axis part of the static iron core in a sliding manner; the closing coils are positioned on two sides of the push rod; the opening coils are positioned on two sides of the push rod; a protruding part of the static iron core is arranged between the closing coil and the opening coil;
the moving contact comprises an A-phase main contact, a B-phase main contact and a C-phase main contact; the B-phase main contact is arranged between the A-phase main contact and the C-phase main contact; and when the switch is switched on, the A-phase main contact and the C-phase main contact are firstly jointed with the static contact to enable the A-phase main contact and the C-phase main contact to be switched on, and then the B-phase main contact is jointed with the static contact to enable the B-phase main contact to be switched on.
2. An ac contactor having a double coil structure with an electromagnetically controllable attraction as a reaction force according to claim 1, wherein: the circuit detection module detects the zero crossing point of the first-phase load current of the three-phase alternating-current circuit, determines a delay time length T by taking the zero crossing point as a reference, and after the delay time length T, the electric control system is switched off by the alternating-current contactor; the closing coil is powered off and the opening coil is powered on through the strong excitation module, the moving contact is driven to be separated from the static contact at a preset speed, three phases of alternating current are quickly disconnected near a load current zero crossing point, and micro-arc opening is achieved.
3. An ac contactor having a double coil structure with an electromagnetically controllable attraction as a reaction force according to claim 1, wherein: the working voltage of the closing coil is a pulsating direct-current voltage obtained by rectifying a single phase of alternating-current voltage by an electric control system; and the electric control system selects an optimal closing phase angle during closing according to the pulsating direct current voltage so that the alternating current contactor finishes closing suction action at the optimal initial closing phase angle.
4. An ac contactor having a double coil structure with an electromagnetically controllable attraction as a reaction force according to claim 1, wherein: after the switching-on coil performs switching-on operation under the strong excitation effect of the strong excitation module, the electric control system enables the switching-on coil to be connected with a low-voltage direct-current power supply under the control of the single chip microcomputer, and the alternating-current contactor enters a low-voltage direct-current holding state.
5. An ac contactor having a double coil structure with an electromagnetically controllable attraction as a reaction force according to claim 4, wherein: and in the low-voltage direct current holding state, the low-voltage direct current power supply connected to the closing coil is a direct current power supply of DC 9V.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811104601.1A CN109192617B (en) | 2018-09-21 | 2018-09-21 | Electromagnetic controllable attraction force is as alternating current contactor of twin coil structure of counter-force |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811104601.1A CN109192617B (en) | 2018-09-21 | 2018-09-21 | Electromagnetic controllable attraction force is as alternating current contactor of twin coil structure of counter-force |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109192617A CN109192617A (en) | 2019-01-11 |
| CN109192617B true CN109192617B (en) | 2020-03-10 |
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| CN201811104601.1A Expired - Fee Related CN109192617B (en) | 2018-09-21 | 2018-09-21 | Electromagnetic controllable attraction force is as alternating current contactor of twin coil structure of counter-force |
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Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2505975Y (en) * | 2000-01-17 | 2002-08-14 | 吕永祥 | Magnetic force operating structure |
| US10176953B2 (en) * | 2016-09-29 | 2019-01-08 | Schneider Electric USA, Inc. | Weld resistant contactor |
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Granted publication date: 20200310 |