Anti-low-voltage interference electricity device
By using a first relay to replace the voltage detection element in the anti-low voltage shaking device, combining the time relay and the main control switch, the problem that the existing device cannot supply stable power under instantaneous voltage drop and long-term loss of voltage is solved, and the stable operation of the inverter and the continuity of automated production is achieved.
Patent Information
- Application Number
- CN202422035724.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-22
- Publication Date
- 2025-08-29
- Estimated Expiration
- 2034-08-22
AI Technical Summary
The existing low-voltage shaking device cannot effectively prevent the motor from shutting down when the voltage drops instantly, and cannot continuously supply power in the case of long-term loss of pressure, affecting automated continuous production.
The anti-low voltage shaking device including a low-voltage control system and a high-voltage power system is adopted. The voltage detection element is replaced by the first relay, combined with the time relay and the main control switch, and the power supply is achieved. The buzzer and communication module are used to remind the shaking device, and the fuse protection current is set, providing a variety of control methods.
It improves the stability of the anti-shaking device, ensures that the inverter can still be maintained under long-term pressure loss, prevents the motor from being shut down, and realizes the stability and flexible control of automated continuous production.
Smart Images
Figure CN223285627U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of low-voltage circuit anti-electrical shaking, and in particular to a low-voltage anti-electrical shaking device. Background Art
[0002] Modern industrial enterprises widely utilize fuse-contactor circuits, or FC circuits, for motor control in 380V AC and 22V AC circuits. This technology offers advantages such as simplicity, reliability, rapid operation, and frequent operation, along with extremely long electrical and mechanical lifespans, making it unmatched by any other control method. However, this technology also has a significant drawback: a brief undervoltage (or power swing) can cause the contactor coil to suddenly lose its pull, causing the motor to stop operating and, in turn, disrupting production. In industries such as petrochemicals, coal mining, and power generation, many motors must operate continuously without human supervision. Therefore, failure to promptly restart and restore motor operation during a voltage drop can lead to production halts, material waste, inefficiency, and even equipment damage, among other economic losses. Automated production lines, on the other hand, employ various low-voltage anti-power-swing devices to mitigate power swings caused by momentary power outages, ensuring the continued automated and continuous operation of critical loads.
[0003] To meet the needs of automated continuous production, DC bus voltage stability is maintained during voltage fluctuations by utilizing DC bus capacitance and the back EMF of the freewheeling motor, thereby achieving anti-swing protection. However, the duration of this protection depends on the load characteristics. Heavy loads can result in a very short anti-swing period. Even during brief voltage fluctuations, the contactor coil may still lose its pull-in force, causing the motor to shut down. To address this issue, low-voltage anti-swing devices use an internal power supply to provide timed power to the contactor coil during voltage fluctuations, achieving a rated anti-swing protection period. Specifically, if the contactor coil suddenly loses its pull-in force due to a voltage drop, the internal power supply is controlled to supply power for a specified period of time to prevent the inverter from shutting down due to the voltage drop, thus achieving the rated anti-swing protection period. However, while this method can guarantee anti-swing protection for the rated time, it relies on voltage sensing elements to monitor the inverter voltage in real time. If the voltage rises rapidly due to sudden events such as lightning strikes or short-circuit reclosing, the voltage sensing elements may be damaged, compromising the anti-swing protection. Furthermore, when a fault in an adjacent line within the main grid or an enterprise's medium-voltage power grid inevitably causes a prolonged voltage loss, the low-voltage anti-sway device cannot maintain power to the contactor coils for an extended period, causing the inverter contactor coils to lose power and shut down, making it difficult to maintain automated, continuous production of critical loads. Restarting the motor may require waiting for the voltage loss to be repaired or for the inverter's power supply method to be changed. However, waiting for this repair or changing the inverter's power supply method is a significant hassle. Therefore, the design of low-voltage anti-sway devices needs further refinement to enhance their stability and facilitate operation of inverters in prolonged voltage loss conditions. This will ensure their widespread adoption and application. Summary of the Invention
[0004] In view of the shortcomings of the existing technology, the present invention provides an anti-low-voltage shaking device that improves the stability of anti-swaying and facilitates the operation of the inverter in a long-term pressure-loss state, so as to overcome the defects of the existing technology.
[0005] The technical solution adopted by the present invention is: an anti-low-voltage electric shaking device, including a low-voltage control system and a high-voltage power system, the high-voltage power system includes an air switch S1 and a first normally open switch of a contactor KM1 connected to the air switch S1; the low-voltage control system includes a coil of a first relay K2, a power supply connection module connected to the coil of the first relay K2, a coil of the contactor KM1 connected to the power supply connection module, and an electric shaking power supply circuit provided on one side of the power supply connection module; the coil of the first relay K2 is connected to the air switch S1; the electric shaking power supply circuit includes a power supply, a control switch connected to the power supply S3, the first normally closed switch of the first relay K2 connected to the control switch S3, the normally open switch of the time relay T1 connected in parallel to the control switch S3, and the power swing protection circuit set on one side of the power supply; the power supply is connected to the first normally closed switch of the first relay K2 through the normally open switch of the time relay T1 or the control switch S3, and the power supply is connected to the power supply connection module through the first normally closed switch of the first relay K2; the said power swing protection circuit includes the coil of the time relay T1 and the second normally closed switch of the first relay K2; the coil of the time relay T1 is connected to the power supply through the second normally closed switch of the first relay K2.
[0006] Preferably, a master control switch S2 is provided on one side of the power supply, and the control switch S3, the normally open switch of the time relay T1 and the coil of the time relay T1 are all connected to the power supply through the master control switch S2. A diode D1 is provided between the master control switch S2 and the power supply, and the master control switch S2 is connected to the power supply through the diode D1. The forward current of the diode D1 is consistent with the current direction of the power supply.
[0007] Preferably, a buzzer H1 is provided on one side of the coil of the time relay T1, and the coil of the time relay T1 is connected to the power supply through the buzzer H1.
[0008] Preferably, the power supply connection module is connected to a communication module, and an antenna E1 and a third normally closed switch of the first relay K2 are provided on one side of the communication module. The antenna E1 is connected to the communication module via the third normally closed switch of the first relay K2.
[0009] Preferably, the power supply connection module is connected to the control loop module, the coil of the contactor KM1 is connected to the loop KM contact of the control loop module, the coil of the contactor KM1 is connected to the power supply connection module through the control loop module, and a control circuit is set on one side of the control loop module.
[0010] Preferably, the control circuit includes a normally closed button switch SB1 and a normally open button switch SB2 and a second normally open switch of the contactor KM1 connected in parallel on one side of the normally closed button switch SB1. The normally closed button switch SB1 is connected to the switch control contact of the control loop module through the normally open button switch SB2 or the contactor KM1.
[0011] Preferably, a fuse F1 is provided between the coil of the first relay K2 and the air switch S1, and the coil of the first relay K2 is connected to the air switch S1 through the fuse F1.
[0012] The beneficial effects of the present invention are: first, the present invention uses the contactor KM1 to control the high-voltage circuit system to be in a power-off or power-on state, and replaces the voltage detection element by setting the first relay K2 to avoid instantaneous high voltage from damaging the voltage detection element, so that when the coil of the first relay K2 is in the power-on state, the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 are both in the disconnected state, that is, the power supply is in the disconnected state; and if there is a power shake in the circuit where the coil of the first relay K2 is located, the first relay K2 cannot absorb the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2, so that the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 are both in the closed state, so that the power supply connection module is powered by the power supply to prevent the inverter from shutting down, so as to meet the stability of anti-power shake. Moreover, the utility model sets a time relay T1 and a power supply to set a rated time to perform an anti-electrical shaking function, and controls the switch S3 in parallel with the normally open switch of the time relay T1 to facilitate manual control of the power supply to the power supply connection module, so as to achieve manual and convenient recovery of important load production requirements, thereby providing multiple control methods for the high-voltage power system.
[0013] Secondly, the present invention can directly cut off the power supply through the master control switch S2, that is, control the activation or deactivation of the power supply circuit. The diode prevents backflow in the power supply circuit and stabilizes the current in the power supply circuit to improve the stability of the power supply circuit. In addition, the present invention provides a buzzer H1, which can sound when the coil of the time relay T1 is energized, thereby conveniently alerting the first relay K2 coil to the presence of power fluctuations in the circuit. Through the communication module, antenna, and the third normally closed switch of the first relay K2, when the coil of the first relay K2 cannot attract the third normally closed switch of the first relay K2, the third normally closed switch of the first relay K2 is closed, thereby connecting the antenna E1 and the communication module, thereby transmitting a power fluctuation signal through the antenna E1 to alert the first relay K2 coil to the presence of power fluctuations in the circuit.
[0014] Again, the utility model sets up a control loop module to use the loop KM contact of the control loop module to power the coil of the contactor KM1, and uses the switch control contact of the control loop module to control the power-on or power-off of the loop KM contact of the control loop module. With the help of the normally open push button switch SB2 and the second normally open switch of the contactor KM1, it is convenient to control the power-on of the control circuit, and then with the help of the normally closed push button switch SB1, it is convenient to control the disconnection of the control circuit. Moreover, the utility model sets up a fuse F1 to provide current protection for the circuit where the coil of the first relay K2 is located, so that when the current of the circuit where the coil of the first relay K2 is located exceeds the specified value, the heat generated by the fuse F1 itself causes the fuse to melt, thereby disconnecting the circuit where the coil of the first relay K2 is located. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a circuit diagram of the utility model. DETAILED DESCRIPTION
[0016] like Figure 1As shown, a low-voltage power shaking device includes a low-voltage control system and a high-voltage power system. The high-voltage power system includes an air switch S1 and a first normally open switch of a contactor KM1 connected to the air switch S1; the motor M used for production is connected to the air switch S1 through the first normally open switch of the contactor KM1 to control the start and stop of the motor M. The low-voltage control system includes a coil of a first relay K2, a power supply connection module 1 connected to the coil of the first relay K2, a coil of the contactor KM1 connected to the power supply connection module 1, and a power shaking power supply circuit provided on one side of the power supply connection module 1; the coil of the first relay K2 is connected to the air switch S1; the power supply connection module 1 is used to supply power to the coil of the first relay K2, the L end of the power supply connection module 1 is connected to the coil of the first relay K2, and the N end of the power supply connection module 1 is connected to the neutral terminal, so that the circuit where the air switch S1 is located is used to power the low-voltage control system to control the power off or on of the coil of the first relay K2, thereby controlling the disconnection or on of the first normally open switch of the contactor KM1, and further controlling the high-voltage power supply. The power system is in a disconnected or powered state; the power supply circuit includes a power supply 2, a control switch S3 connected to the power supply 2, a first normally closed switch of the first relay K2 connected to the control switch S3, a normally open switch of the time relay T1 connected in parallel to the control switch S3, and a power supply 2 side The power supply 2 is connected to the first normally closed switch of the first relay K2 through the normally open switch of the time relay T1 or the control switch S3, and the power supply 2 is connected to the power supply connection module 1 through the first normally closed switch of the first relay K2; the power supply circuit includes a coil of the time relay T1 and a second normally closed switch of the first relay K2; the coil of the time relay T1 is connected to the power supply 2 through the second normally closed switch of the first relay K2. The first relay K2 replaces the voltage detection element. When the coil of the first relay K2 is energized, the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 are both in the open state, causing the power supply 2 to be in the disconnected state. However, if the circuit where the coil of the first relay K2 is located experiences a power shake, the first relay K2 cannot attract the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2, causing the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 to be in the closed state. Then, the coil of the time relay T1 is energized and attracts the normally open switch of the time relay T1, causing the normally open switch of the time relay T1 to be in the closed state, thereby using the power supply 2 to power the power connection module 1. The time relay T1 is a delayed contact disconnection relay. After the coil of the time relay T1 is de-energized, the time relay T1 resets the set time. After the time relay T1 reaches the set time, the normally open switch of the time relay T1 is disconnected.To this end, if the power supply circuit where the air switch S1 is located is still shaking after the set time of the time relay T1 is reached, the normally open switch of the time relay T1 will be disconnected, and the power supply connection module 1 will stop being supplied, thereby controlling the first normally open switch of the contactor KM1 to be disconnected; if the first normally closed switch of the first relay K2 needs to be controlled to be closed, the control switch S3 needs to be manually closed to use the power supply 2 to supply power to the power supply connection module 1 to facilitate the restoration of the automated continuous production of important loads, thereby providing multiple control methods for the high-voltage power system.
[0017] In this embodiment, a master switch S2 is provided on one side of the power supply 2. The control switch S3, the normally open switch of the time relay T1, and the coil of the time relay T1 are all connected to the power supply 2 via the master switch S2. Therefore, the power supply 2 can be shut off by disconnecting the master switch S2. A diode D1 is provided between the master switch S2 and the power supply 2. The forward current of the diode D1 aligns with the current of the power supply 2, thereby preventing reverse current in the power supply circuit and stabilizing the current flow.
[0018] Specifically, a buzzer H1 is provided on one side of the coil of the time relay T1. The coil of the time relay T1 is connected to the power supply 2 through the buzzer H1. Therefore, when the coil of the time relay T1 is energized, the buzzer H1 is also energized, causing the buzzer H1 to emit a sound to facilitate the reminder that there is a power shake in the circuit where the coil of the first relay K2 is located.
[0019] It should be noted that the power supply connection module 1 is connected to the communication module 3, and an antenna E1 and a third normally closed switch of the first relay K2 are provided on one side of the communication module 3. The antenna E1 is connected to the communication module 3 through the third normally closed switch of the first relay K2. For this reason, if there is a power shake in the circuit where the coil of the first relay K2 is located, the coil of the first relay K2 cannot absorb the third normally closed switch of the first relay K2, so that the third normally closed switch of the first relay K2 is in a closed state, thereby connecting the antenna E1 and the communication module 3, thereby transmitting a power shake signal through the antenna E1 to remind the first relay K2 that there is a power shake in the circuit where the coil is located. The communication module 3 adopts an RS485 communication module. Since the RS485 communication module has the ability to suppress common-mode interference, it is convenient to send signals stably.
[0020] In this embodiment, the power supply connection module 1 is connected to a control circuit module 4. The coil of the contactor KM1 is connected to the loop KM contact of the control circuit module 4. The coil of the contactor KM1 is connected to the power supply connection module 1 through the control circuit module 4. A control circuit is provided on one side of the control circuit module 4. The control circuit module 4 uses any one of a single-chip microcomputer, DSP, and ARM control chip, which is equipped with a corresponding control program. The loop KM contact of the control circuit module 4 is used to power the coil of the contactor KM1.
[0021] Specifically, the control circuit includes a normally closed pushbutton switch SB1, a normally open pushbutton switch SB2 connected in parallel to one side of the normally closed pushbutton switch SB1, and a second normally open switch of the contactor KM1. The normally closed pushbutton switch SB1 is connected to the switch control contacts of the control circuit module 4 via the normally open pushbutton switch SB2 or the contactor KM1. The switch control contacts of the control circuit module 4 are used to control whether the circuit KM contacts of the control circuit module 4 are energized or disconnected. By pressing the normally open pushbutton switch SB2, if the control circuit is energized, the circuit KM contacts of the control circuit module 4 supply power to the coil of the contactor KM1, causing the coil of the contactor KM1 to attract the first normally open switch and the second normally open switch of the contactor KM1, thereby closing and energizing the first and second normally open switches of the contactor KM1. Therefore, even after releasing the normally open pushbutton switch SB2, the control circuit remains energized. If it is necessary to close the first normally open switch of contactor KM1, by pressing the normally closed push button switch SB1, the normally closed push button switch SB1 is in the off state, the power to the control circuit is disconnected, and the coil of contactor KM1 loses its attraction force, thereby disconnecting the first normally open switch of contactor KM1 and the second normally open switch of contactor KM1.
[0022] In this embodiment, a fuse F1 is provided between the coil of the first relay K2 and the air switch S1. The coil of the first relay K2 is connected to the air switch S1 through the fuse F1. Therefore, when the current of the circuit where the coil of the first relay K2 is located exceeds the specified value, the heat generated by the fuse F1 itself causes the fuse to melt, thereby disconnecting the circuit where the coil of the first relay K2 is located, thereby achieving current protection for the circuit where the coil of the first relay K2 is located.
[0023] The method of using this product is as follows: Figure 1As shown, first, the air switch S1 is merged, and the rated time of the time relay T1 is set according to the requirements of the high-voltage power system. The main control switch S2 is closed, and then the control switch S3 is opened, so that the power supply circuit of the power supply circuit is in a state to be started. Since the power supply circuit is a short-term phenomenon of the circuit system, the rated time of the time relay T1 is set to 1-9 seconds. Then, the normally open button switch SB2 is pressed. If the control circuit is in the power-on state, the loop KM contact of the control loop module 4 supplies power to the coil of the contactor KM1, so that the coil of the contactor KM1 attracts the first normally open switch of the contactor KM1 and the second normally open switch of the contactor KM1, thereby making the first normally open switch of the contactor KM1 and the second normally open switch of the contactor KM1 in the closed power-on state. After releasing the normally open button switch SB2, the control circuit is still in the power-on state. At the same time, the high-voltage power system is controlled to be in the power-on state.
[0024] If a power shake occurs in the circuit where the coil of the first relay K2 is located, the first relay K2 cannot attract the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2, so that the first normally closed switch of the first relay K2, the second normally closed switch of the first relay K2, and the third normally closed switch of the first relay K2 are all in the closed state. To this end, the coil of the time relay T1 is energized to attract the normally open switch of the time relay T1, so that the normally open switch of the time relay T1 is in the closed state, thereby using the power supply 2 to power the power connection module 1 within the rated time of the time relay T1, so that the coil of the contactor KM1 attracts the first normally open switch of the contactor KM1 and the second normally open switch of the contactor KM1. At the same time, the buzzer H1 is energized to emit a sound, and the antenna E1 is energized to emit a message to remind the user of the power shake.
[0025] When the power grid where the high-voltage power system is located is in a state of prolonged voltage loss, in order to ensure that important loads maintain automated and continuous production, personnel manually close the control switch S3 to use power supply 2 to power the power connection module 1, thereby causing the coil of contactor KM1 to attract the first normally open switch of contactor KM1 and the second normally open switch of contactor KM1 to meet the power supply needs of important loads. In addition, it should be noted that the control switch S3 can be replaced with a parallel normally closed push button switch SB3 and the third normally open switch of contactor KM1 to avoid forgetting to disconnect the control switch S3 after the power grid where the high-voltage power system is located recovers its voltage.
[0026] Through this embodiment, by using the contactor KM1 to control the high-voltage circuit system to be in a power-off or power-on state, the first relay K2 is provided to replace the voltage detection element to prevent instantaneous high voltage from damaging the voltage detection element, so that when the coil of the first relay K2 is in the energized state, the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 are both in the open state, so that the power supply 2 is in the disconnected state; and if there is a power shake in the circuit where the coil of the first relay K2 is located, the first relay K2 cannot attract the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2, so that the first normally closed switch of the first relay K2 and the second normally closed switch of the first relay K2 are both in the closed state, so that the power supply connection module 1 is powered by the power supply to prevent the inverter from shutting down and meet the stability of anti-power shake. In addition, the utility model uses the time relay and power supply to set the rated time for anti-power shake function, and controls the switch S3 in parallel on the normally open switch of the time relay T1 to facilitate manual control of the power supply 2 to power the power supply connection module 1, so as to achieve the production requirements of manually restoring important loads, thereby providing multiple control methods for the high-voltage power system.
[0027] The embodiments described above are only preferred embodiments of the present invention and do not limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made based on the structure, features and principles described in the patent scope of the present invention should be included in the scope of the patent application of the present invention.
Claims
1. A low-voltage power sway protection device, comprising a low-voltage control system and a high-voltage power system, characterized in that: The high-voltage power system includes an air switch S1 and a first normally open switch of a contactor KM1 connected to the air switch S1; The low-voltage control system includes a coil of a first relay K2, a power supply connection module (1) connected to the coil of the first relay K2, a coil of a contactor KM1 connected to the power supply connection module (1), and a power supply circuit provided on one side of the power supply connection module (1); the coil of the first relay K2 is connected to the air switch S1; The power supply circuit for power fluctuations comprises a power supply (2), a control switch S3 connected to the power supply (2), a first normally closed switch of a first relay K2 connected to the control switch S3, a normally open switch of a time relay T1 connected in parallel to the control switch S3, and a power fluctuation protection circuit provided on one side of the power supply (2); The power supply (2) is connected to the first normally closed switch of the first relay K2 via the normally open switch of the time relay T1 or the control switch S3, and the power supply (2) is connected to the power supply connection module (1) via the first normally closed switch of the first relay K2; The shaking protection circuit includes a coil of a time relay T1 and a second normally closed switch of a first relay K2; the coil of the time relay T1 is connected to a power source (2) via the second normally closed switch of the first relay K2.
2. The low-voltage power sway protection device according to claim 1, characterized in that: A master control switch S2 is provided on one side of the power supply (2), and the control switch S3, the normally open switch of the time relay T1, and the coil of the time relay T1 are all connected to the power supply (2) through the master control switch S2. A diode D1 is provided between the master control switch S2 and the power supply (2). The master control switch S2 is connected to the power supply (2) through the diode D1, and the forward current of the diode D1 is consistent with the current direction of the power supply (2).
3. The low-voltage power sway protection device according to claim 1, wherein: A buzzer H1 is provided on one side of the coil of the time relay T1, and the coil of the time relay T1 is connected to the power supply (2) through the buzzer H1.
4. The low-voltage power sway protection device according to claim 1, wherein: The power supply connection module (1) is connected to a communication module (3), and an antenna E1 and a third normally closed switch of the first relay K2 are provided on one side of the communication module (3). The antenna E1 is connected to the communication module (3) via the third normally closed switch of the first relay K2.
5. The low-voltage power sway protection device according to claim 1, wherein: The power supply connection module (1) is connected to the control loop module (4), the coil of the contactor KM1 is connected to the loop KM contact of the control loop module (4), the coil of the contactor KM1 is connected to the power supply connection module (1) through the control loop module (4), and a control circuit is provided on one side of the control loop module (4).
6. The low-voltage power sway protection device according to claim 5, characterized in that: The control circuit includes a normally closed push button switch SB1 and a normally open push button switch SB2 and a second normally open switch of the contactor KM1 connected in parallel on one side of the normally closed push button switch SB1. The normally closed push button switch SB1 is connected to the switch control contact of the control circuit module (4) through the normally open push button switch SB2 or the contactor KM1.
7. The low-voltage power sway protection device according to claim 1, characterized in that: A fuse F1 is provided between the coil of the first relay K2 and the air switch S1 , and the coil of the first relay K2 is connected to the air switch S1 through the fuse F1 .