CN111477501A - A Magnetic Retaining Operating Mechanism for Direct Opening of Microcomputer Protection Device - Google Patents

Abstract

The invention discloses a magnetic holding operating mechanism that can be directly driven by a microcomputer protection device to open the gate. It is composed of a washer, a cylindrical moving iron core armature and an upper magnetic insulating plate. By increasing the working voltage of the excitation coil, reducing the volume of the excitation coil, improving the structure of the yoke and reducing the magnetic resistance, the excitation coil is wound according to specific working parameters. It can meet the protection output drive parameters of the microcomputer protection device, realize the direct drive opening of the microcomputer protection device, and reduce the protection trip time of the medium and high voltage circuit breaker; it can also increase the line resistance of the excitation coil, reduce the closing drive current, the saturation conduction current, and reduce the excitation. Risk of thermal damage to the coil.

Description

A Magnetic Retaining Operating Mechanism for Direct Opening of Microcomputer Protection Device

technical field

The invention relates to high and low voltage vacuum electrical switch accessories, in particular to an operating mechanism, and belongs to the technical field of electrical appliances.

Background technique

In the current power transmission and distribution system, circuit breaker switches with spring mechanisms are commonly used. The control signal is output by the microcomputer protection device to drive the shunt release on the spring mechanism. The action of the shunt release releases the power of the energy storage spring and drives the circuit breaker to open. From the output of the microcomputer protection device to the opening of the circuit breaker, the spring mechanism circuit breaker switch requires a relatively long time, and cannot adapt to the higher distribution network grading protection arrangement. In recent years, the permanent magnet holding operating mechanism has attracted widespread attention in the industry due to its advantages of high reliability, long life, and easy control. Popularized and applied, although the components of the permanent magnet holding operating mechanism are few, they can form a variety of magnetic circuit structures. In the process of vacuum switch state transition, the static mechanical characteristics, dynamic mechanical characteristics and motion characteristics of the time-related mechanical, electrical and magnetic coupling are very different, which directly affect the control system, operating mechanism and vacuum switch. matching properties. At present, in the application process of the permanent magnet holding operating mechanism, the driving voltage of the excitation coil is DC110V or DC220V. In order to output enough power within the specified time, the line resistance of the excitation coil is often small, which brings a disadvantage: the short-circuit current of the excitation coil is very high. It is so large that in the case of continuous operation, the excitation coil is seriously heated until it is burned out, and the circuit components of the control system will also be burned out due to overcurrent. The control system and the excitation coil are easily damaged, which also seriously affects the application prospect of the permanent magnet holding operating mechanism.

SUMMARY OF THE INVENTION

In order to solve the problems existing in the application process of the current spring mechanism circuit breaker and the permanent magnet holding operating mechanism circuit breaker, the present invention discloses a magnetic holding operating mechanism in which the microcomputer protection device is directly opened. By increasing the working voltage of the excitation coil, accurately controlling the conduction time of the excitation coil, reducing the wire diameter of the excitation coil, increasing the wire resistance of the excitation coil, reducing the diameter of the outer ring of the excitation coil, optimizing the design of the magnetic circuit system, and reducing the magnetic resistance of the magnetic conducting circuit; and Compared with the traditional permanent magnet operating mechanism, under the condition of outputting the same driving force, the new magnetic holding operating mechanism can reduce the volume by one-third, reduce the peak current of the excitation coil by one-half, and can reduce overcurrent, Risk of overheating damage; at the same time, after reducing the driving current, the new magnetic latching operating mechanism can directly drive the opening through the microcomputer protection device. Compared with the spring mechanism, the microcomputer protection device directly drives the magnetic latching operating mechanism to open, which can reduce The action time of the spring mechanism shunt release will ultimately reduce the protection opening time, which is beneficial to the hierarchical protection arrangement of the power transmission and distribution network.

The working process of the permanent magnet holding operating mechanism is: when the excitation coil is positively loaded with a power supply for a certain period of time, the positive electromagnetic field generated by the excitation coil superimposes the permanent magnet field of the permanent magnet, and the moving iron passes through the magnetic conductive yoke and the working air gap. The core armature generates the clap motion, outputs the closing operating force, and completes the closing action. After closing, the permanent magnet field of the permanent magnet passes through the magnetic conductive yoke and the moving iron core armature to maintain the suction force of the clap surface, and outputs the closing retention force. , enter the closing state; when the excitation coil is reversely loaded with the power supply for a certain period of time, the reverse electromagnetic field generated by the excitation coil reduces the permanent magnet field of the permanent magnet, and the suction force of the snap-fit surface decreases. After reaching the critical point, under the action of external force, The moving iron core armature is separated from the yoke to complete the opening action and enter the opening state.

Under the condition that the number of turns of the excitation coil is unchanged, reducing the diameter of the wire can reduce the diameter of the outer circle of the excitation coil, which can increase the wire resistance of the excitation coil; increasing the loading voltage of the excitation coil can keep the excitation coil at a suitable number of ampere turns, so , the excitation coil has optimal parameters. Under the condition that the cross-sectional area of the magnetic permeability remains unchanged, reducing the diameter of the outer ring of the excitation coil can reduce the diameter of the outer magnetic yoke and the length of the magnetic conductive circuit, that is, reduce the magnetic resistance of the magnetic conductive circuit, which can improve the working air gap. Magnetic flux, improve the suction force of the clap surface. Therefore, under the condition that the closing actuation force and the output of the permanent magnet braking holding force remain unchanged, the area of the contact surface is not changed, the diameter of the outer yoke is appropriately reduced, the diameter of the wire is reduced, and the working parameters of the excitation coil are improved, which can reduce the excitation Risk of overcurrent damage to the coil.

The technical scheme adopted in the present invention is:

A magnetic holding operating mechanism for direct opening of a microcomputer protection device, comprising a drive shaft (1), a guide sleeve (2), a lower magnetic insulating plate (3), a cylindrical inner magnetic yoke (4), and a permanent magnet (5) , excitation coil (6), cylindrical outer yoke (7), washer (8), cylindrical moving iron core armature (9) and upper magnetic insulating plate (11), the permanent magnet (5) provides a permanent magnetic field source, The current and direction of the excitation coil (6) are controlled by the control circuit to generate positive and negative instantaneous electromagnetic fields and the superposition of the permanent magnetic field, drive the cylindrical moving iron core armature (9), drive the drive shaft (1), transmit power, and complete the opening and closing The conversion between the action and the closing permanent magnet holding state; wherein, the cylindrical inner yoke (4) is inserted into the guide sleeve (2) in the center, the drive shaft (1) passes through the guide sleeve (2), the cylindrical inner yoke (4) and the center of the lower magnetic insulating plate (3); the cylindrical outer yoke (7) is composed of two parts, a thick-walled cavity and a thin-walled cavity, and the thick-walled cavity of the cylindrical outer yoke (7) is filled with washers in turn. (8), excitation coil (6), cylindrical inner yoke (4), permanent magnet (5) and guide sleeve (2), the thin-walled cavity of the cylindrical outer yoke (7) is a cylindrical moving iron core The upper and lower movement space of the armature (9), the upper and lower magnetic insulating plates (11) and the lower magnetic insulating plates (3) are fixed on the upper and lower end faces of the cylindrical outer yoke (7), forming one end closed and one end with the output of the drive shaft (1) the operating mechanism as a whole.

The opening working parameters of the excitation coil (6) meet the output control parameters of the microcomputer protection device, so that the microcomputer protection device can directly control the opening; the specific working parameters of the excitation coil (6) are: the two ends of the excitation coil (6) are connected by The energy storage capacitor with energy storage voltage between DC260V ~ DC450V applies power forward for 30mS ~ 80mS, the microcomputer protection device directly opens the magnetic latching operating mechanism to reliably close, and the closing current is between 20A ~ 100A , the closing response time is not more than 1mS, the closing action time is between 30mS and 80mS, and the short-circuit current of the excitation coil (6) is not more than 100A; when the reverse voltage of the excitation coil (6) is applied DC140V ~ DC450V, the excitation coil ( 6) The generated reverse electromagnetic field makes the permanent magnet hold invalid, and the magnetic hold operating mechanism of the microcomputer protection device is opened reliably, the opening current is 1A~5A, the response time is not more than 1mS, and the opening action time is not more than 20mS; when the reverse applied voltage at both ends of the excitation coil (6) is lower than DC100V, the reverse electromagnetic field generated by the excitation coil (6) cannot make the permanent magnet retention fail, and the magnetic retention operating mechanism of the microcomputer protection device directly opening is reliable Do not switch off. Under normal circumstances, the protection action output of the microcomputer protection device can provide a driving signal with a voltage of DC220V or AC220V and a current of not less than 5A. Therefore, the working parameters of the excitation coil (6) can meet the requirements of the action output parameters of the microcomputer protection device, and realize the microcomputer protection device. Open directly.

The thick-walled cavity and the thin-walled cavity form a stage-level separation on the inner wall of the cylindrical outer magnetic yoke (7), and there is a boss (14) on the side edge of the stage-level thick-walled cavity into the cavity. When the magnetic holding operating mechanism of the microcomputer protection device for direct opening is in the closed state, the lower end face of the cylindrical moving iron core armature (9) on which the drive shaft (1) is installed and the upper end face of the cylindrical inner magnetic yoke (4) Form a snap surface (13); the upper part of the cylindrical moving iron core armature (9) has an "umbrella"-shaped structure, and the lower cross section of the outer edge of the "umbrella"-shaped structure of the cylindrical moving iron core armature (9) is connected to the cylindrical outer magnetic The stage-level cross-section of the inner wall of the yoke (7) forms a snap surface (12), and the permanent magnetic field generated by the permanent magnet (5) passes through the magnetic conductor cylindrical outer yoke (7), which is a thick-walled, cylindrical moving iron core armature (9). , the cylindrical inner yoke (4) and the snap surface (12) and the snap surface (13) form a magnetic circuit; the boss (14) on the edge of the thick-walled cavity of the cylindrical outer yoke (7) The magnetic conductive cross-sectional area of the magnetic conductive body and the area of the snap-fit surface (12) can be increased, the magnetic resistance can be reduced, the magnetic flux can be increased, and the holding force generated by the permanent magnet (5) can be improved.

The cylindrical moving iron core armature (9) on which the drive shaft (1) is installed is a moving whole, the upper and lower ends of the drive shaft (1) are provided with a central conical hole (16), and the cylindrical moving iron core armature (9) ) The outer cylindrical surface of the upper "umbrella"-shaped structure has a right-angle concave stage (15), and its cylindrical surface is concentric with the tapered hole on the end face of the drive shaft (1) to ensure that the drive shaft (1) and the cylindrical moving iron core armature (9) Processing consistency.

Description of drawings

Fig. 1 is the open state of the magnetic holding operating mechanism of the direct opening of the microcomputer protection device.

Fig. 2 is the closed state of the magnetic holding operating mechanism of the direct opening of the microcomputer protection device.

Detailed ways

In contrast to Figure 1, a magnetic holding operating mechanism for direct opening of a microcomputer protection device includes a drive shaft (1), a guide sleeve (2), a lower magnetic insulating plate (3), a cylindrical inner magnetic yoke (4), a permanent magnet (5), the excitation coil (6), the cylindrical outer yoke (7), the washer (8), the cylindrical moving iron core armature (9) and the upper magnetic insulating plate (11), the permanent magnet (5) provides permanent The magnetic field source is controlled by the control circuit to control the current and direction of the excitation coil (6) to generate positive and negative instantaneous electromagnetic fields and the superposition of the permanent magnetic field, drive the cylindrical moving iron core armature (9), drive the drive shaft (1), transmit power, and complete The switching of the opening and closing action and the closing permanent magnet holding state; wherein, the cylindrical inner yoke (4) is inserted into the guide sleeve (2) in the center, and the drive shaft (1) passes through the guide sleeve (2), the cylindrical inner yoke (4) and the center of the lower magnetic insulating plate (3); the cylindrical outer yoke (7) is composed of two parts: a thick-walled cavity and a thin-walled cavity, and the thick-walled cavity of the cylindrical outer yoke (7) is in turn. Load the washer (8), the excitation coil (6), the cylindrical inner yoke (4), the permanent magnet (5) and the guide sleeve (2), and the thin-walled cavity of the cylindrical outer yoke (7) is cylindrical The upper and lower moving space of the moving iron core armature (9), the upper and lower magnetic insulating plates (11) and the lower magnetic insulating plates (3) are fixed on the upper and lower end faces of the cylindrical outer magnetic yoke (7), forming a closed end and a drive shaft ( 1) The entire output operating mechanism.

The wire diameter of the excitation coil (6) is 1.0mm and wound by 780 turns, the length is 75mm, the inner diameter is 60mm, and the outer diameter is 103mm. The energy storage capacitor between the two is positively applied with power for 30mS～80mS, the magnetic latching operating mechanism of the microcomputer protection device is directly opened and closed reliably, the closing current is between 20A and 100A, and the closing response time is not more than 1mS, the closing action time is between 30mS and 80mS, the short-circuit current of the excitation coil (6) is not more than 100A; when the reverse voltage of DC140V～DC450V is applied to the two ends of the excitation coil (6), the reverse electromagnetic field generated by the excitation coil (6) To make the permanent magnet holding invalid, the magnetic holding operating mechanism of the microcomputer protection device directly opening the gate can reliably open the gate, the opening current is 1A-5A, the response time is not more than 1mS, and the opening action time is not more than 20mS; the excitation coil (6) When the reverse applied voltage at both ends is lower than DC100V, the reverse electromagnetic field generated by the excitation coil (6) cannot make the permanent magnet retention fail, and the magnetic retention operating mechanism of the microcomputer protection device directly opening is reliable and not opening. Under normal circumstances, the protection action output of the microcomputer protection device can provide a driving signal with a voltage of DC220V or AC220V and a current of not less than 5A. Therefore, the working parameters of the excitation coil (6) can meet the requirements of the action output parameters of the microcomputer protection device, and realize the microcomputer protection device. Open directly.

Referring to Figure 2, the thick-walled cavity and the thin-walled cavity form a stage-level separation on the inner wall of the cylindrical outer yoke (7), and there is a boss (14) on the side edge of the stage-level thick-walled cavity toward the cavity. . When the magnetic holding operating mechanism of the microcomputer protection device for direct opening is in the closed state, the lower end face of the cylindrical moving iron core armature (9) on which the drive shaft (1) is installed and the upper end face of the cylindrical inner magnetic yoke (4) Form a snap surface (13); the upper part of the cylindrical moving iron core armature (9) has an "umbrella"-shaped structure, and the lower cross section of the outer edge of the "umbrella"-shaped structure of the cylindrical moving iron core armature (9) is connected to the cylindrical outer magnetic The stage-level cross-section of the inner wall of the yoke (7) forms a snap surface (12), and the permanent magnetic field generated by the permanent magnet (5) passes through the magnetic conductor cylindrical outer yoke (7), which is a thick-walled, cylindrical moving iron core armature (9). , the cylindrical inner yoke (4) and the snap surface (12) and the snap surface (13) form a magnetic circuit; the boss (14) on the edge of the thick-walled cavity of the cylindrical outer yoke (7) The magnetic conductive cross-sectional area of the magnetic conductive body and the area of the snap-fit surface (12) can be increased, the magnetic resistance can be reduced, the magnetic flux can be increased, and the holding force generated by the permanent magnet can be improved.

The cylindrical moving iron core armature (9) on which the drive shaft (1) is installed is a moving whole, the upper and lower ends of the drive shaft (1) are provided with a central conical hole (16), and the cylindrical moving iron core armature (9) ) The outer cylindrical surface of the upper "umbrella"-shaped structure has a right-angle concave stage (15), and its cylindrical surface is concentric with the tapered hole on the end face of the drive shaft (1) to ensure that the drive shaft (1) and the cylindrical moving iron core armature (9) Processing consistency.

The working process of the magnetic holding operation mechanism of the microcomputer protection device directly opening is as follows: the external lead of the excitation coil (6) is respectively connected to the external drive circuit and the protection output port of the microcomputer protection device through the isolation switch; under the control of the external drive circuit , when the excitation coil (6) is positively loaded with a power supply with a duration of 30mS and a voltage of 300V, the positive electromagnetic field generated by the excitation coil (6) superimposes the permanent magnet field of the permanent magnet (5), and passes through the cylindrical outer yoke (7) of the magnetic conductor. , The cylindrical inner magnetic yoke (4) and the cylindrical moving iron core armature (9) act on the working air gap between the above-mentioned magnetic conductors to form a magnetic pressure drop and force, resulting in the cylindrical moving iron core armature (9) Moving in the direction of the cylindrical inner yoke (4), that is, the snap-fit movement, the closing actuating force is output by the drive shaft (1), and the lower end face of the cylindrical moving iron armature (9) and the cylindrical inner yoke ( 4) On the upper end face, the "umbrella" surface of the cylindrical moving iron core armature (9) is in complete contact with the stage surface in the cylindrical outer yoke (7), that is, the snap-fit surface (12) and the snap-fit surface (13) ) is completely contacted to complete the closing action; after closing, the permanent magnetic field of the permanent magnet (5) passes through the magnetic conductor cylindrical outer yoke (7), the cylindrical inner yoke (4) and the cylindrical moving iron core armature ( 9), to keep the suction force of the snap surface (12) and the snap surface (13), the closing force is output by the drive shaft (1), and the closing state is entered; it is output by the protection output port of the microcomputer protection device or other drive circuits. Control, when the excitation coil (6) is reversely loaded with a voltage DC200V power supply, the reverse electromagnetic field generated by the excitation coil (6) reduces the permanent magnet field of the permanent magnet (5), the snap-fit surface (12) and the snap-fit surface (13) Keep the suction force down, and after reaching the critical point, through the drive shaft (1), under the action of external force, the cylindrical moving iron core armature (9) is separated from the cylindrical outer yoke (7) and the cylindrical inner yoke (4) , to complete the opening action and enter the opening state.

The magnetic latching operating mechanism of the microcomputer protection device for direct opening is applied to the operation of the CBC1 type 10KV1600A 31.5KA circuit breaker, and the continuous opening and closing tests are performed 50,000 times at 20-second intervals, and there is no overheating phenomenon and no overcurrent. Flow burns out components.

Claims (5)

1. A magnetic holding operating mechanism for direct opening of a microcomputer protection device, comprising a drive shaft (1), a lower magnetic insulating plate (3), a cylindrical inner magnetic yoke (4), a permanent magnet (5), an excitation coil ( 6), a cylindrical outer yoke (7), a cylindrical moving iron core armature (9) and an upper magnetic insulating plate (11), the permanent magnet (5) provides a permanent magnetic field source, and the excitation coil (6) is controlled by the control circuit The current and direction generate positive and negative instantaneous electromagnetic fields and the superposition of the permanent magnetic field, drive the cylindrical moving iron core armature (9), drive the drive shaft (1), transmit power, and complete the switching between the opening and closing action and the closing permanent magnet holding state It is characterized in that it also includes a guide sleeve (2) and a washer (8); the cylindrical inner yoke (4) is centrally loaded into the guide sleeve (2), and the drive shaft (1) passes through the guide sleeve (2) and the cylindrical inner yoke (2). The center of the yoke (4) and the lower magnetic insulating plate (3); the cylindrical outer yoke (7) is composed of two parts: a thick-walled cavity and a thin-walled cavity, and the thick-walled cavity of the cylindrical outer yoke (7) The washer (8), the excitation coil (6), the cylindrical inner yoke (4), the permanent magnet (5) and the guide sleeve (2) are sequentially loaded into the body, and the thin-walled cavity of the cylindrical outer yoke (7) is The upper and lower moving space of the cylindrical moving iron core armature (9), the upper and lower magnetic insulating plates (11) and the lower magnetic insulating plates (3) are fixed on the upper and lower end faces of the cylindrical outer magnetic yoke (7), forming one end closed and one end driven The whole of the operating mechanism output by the shaft (1); the opening working parameters of the excitation coil (6) meet the output control parameters of the microcomputer protection device, so that the microcomputer protection device can directly control the opening. 2. The magnetic holding operating mechanism for direct opening of the microcomputer protection device according to claim 1, characterized in that: the working parameters of the excitation coil (6) are: reversely apply a voltage DC140V at both ends of the excitation coil (6) When ~DC450V, the reverse electromagnetic field generated by the excitation coil (6) makes the permanent magnet hold invalid, and the magnetic hold operating mechanism of the microcomputer protection device directly opens the brake reliably, the opening current is 1A~5A, and the response time is not more than 1mS , the opening action time is not more than 20mS; when the reverse applied voltage at both ends of the excitation coil (6) is lower than DC100V, the reverse electromagnetic field generated by the excitation coil (6) cannot make the permanent magnet hold invalid, and the microcomputer protection device directly divides The magnetic holding operating mechanism of the gate is reliable and does not open the gate; the microcomputer protection device can be directly opened; at both ends of the excitation coil (6), the power is positively applied by the energy storage capacitor whose energy storage voltage is between DC260V ~ DC450V, lasting 30mS ～80mS, the magnetic latching operating mechanism of the microcomputer protection device is closed reliably, the closing current is between 20A and 100A, the closing response time is not more than 1mS, the closing action time is between 30mS and 80mS, and the excitation The short-circuit current of the coil (6) is not more than 100A. 3. A magnetic holding operating mechanism for direct opening of a microcomputer protection device according to claim 1, characterized in that: the thick-walled cavity and the thin-walled cavity form a stage on the inner wall of the cylindrical outer magnetic yoke (7). There is also a boss (14) on the side edge of the thick-walled cavity of the stage level into the cavity. 4. According to claim 1 and claim 3, the magnetic holding operating mechanism of the microcomputer protection device directly opening is characterized in that when the magnetic holding operating mechanism of the microcomputer protection device directly opening is in the closed state, the installation The lower end face of the cylindrical moving iron core armature (9) of the drive shaft (1) and the upper end face of the cylindrical inner magnetic yoke (4) form a clap surface (13); the upper part of the cylindrical moving iron core armature (9) has " Umbrella"-shaped structure, the lower cross section of the outer edge of the "umbrella"-shaped structure of the cylindrical moving iron core armature (9) and the stage-level cross section of the inner wall of the cylindrical outer yoke (7) form a snap surface (12), the permanent magnet (5) The generated permanent magnetic field passes through the thick wall of the magnetic conductor cylindrical outer yoke (7), the cylindrical moving iron core armature (9), the cylindrical inner magnetic yoke (4) and the snapping surface (12), the snapping surface (13) A magnetic circuit is formed; the boss (14) on the edge of the thick-walled cavity of the cylindrical outer yoke (7) can increase the magnetic conducting cross-sectional area of the magnet and the area of the mating surface (12), reduce the Reluctance, increasing the magnetic flux, increasing the holding force produced by the permanent magnets (5). 5. A magnetic holding operating mechanism for direct opening of a microcomputer protection device according to claim 4, characterized in that the cylindrical moving iron core armature (9) on which the drive shaft (1) is installed is a moving whole, which drives the The upper and lower ends of the shaft (1) are provided with a central conical hole (16), and the outer cylindrical surface of the upper "umbrella"-shaped structure of the cylindrical moving iron core armature (9) has a right-angled concave stage (15), the cylindrical surface of which is parallel to the outer cylindrical surface of the "umbrella" structure. The tapered hole on the end face of the drive shaft (1) is concentric.

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