Low-power trip coil control circuit

Abstract

The utility model belongs to the technical field of trip control, and relates to a low-power trip coil control circuit which comprises a voltage stabilizing circuit, a comparison circuit and an execution circuit which are electrically connected, and the voltage stabilizing circuit provides stable reference voltage for the low-power trip coil control circuit; the comparison circuit receives the reference voltage from the voltage stabilizing circuit and the voltage to be measured at the two ends of the trip coil, and generates a control signal by comparing the two voltages; and the execution circuit controls the on-off of the low-power trip coil according to the control signal output by the comparison circuit. On-off control of a circuit is realized by controlling on-off of a trip coil, so that the circuit and equipment are protected from being influenced by abnormal conditions such as overload and short circuit; the device is low in power, safe and reliable, and can be widely applied to the fields of energy storage systems, electric power systems, transportation, petrochemical engineering, electrical control and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of tripping control, and more specifically, to a low-power tripping coil control circuit. Background Art

[0002] The tripping coil control circuit is a control circuit designed based on the electromagnetic principle and is mainly used in circuit protection devices such as circuit breakers and contactors. This circuit controls the on-off of the tripping coil to achieve the opening and closing control of the circuit, so as to protect the circuit and equipment from abnormal conditions such as overload and short circuit.

[0003] The shunt trip is used for remote operation of the low-voltage circuit breaker to trip. Its electromagnetic coil is connected in parallel on the power supply side of the low-voltage circuit breaker. When a trip operation is required, press the normally open button to energize the electromagnet of the shunt trip to attract the armature, and through the transmission mechanism, push the free trip mechanism to trip the low-voltage circuit breaker. For some special application scenarios such as transportation, petrochemical, and electrical control fields, the power of remote operation of the trip is limited. The tripping coil control circuits used in the prior art usually have high power, and the cost increases accordingly, which is not conducive to environmental protection. Summary of the Utility Model

[0004] The technical problem to be solved by the utility model is that the tripping coil control circuits used in the prior art usually have high power, and the cost increases accordingly, which is not conducive to environmental protection. In view of the above defects of the prior art, a low-power tripping coil control circuit is provided, including:

[0005] A voltage stabilizing circuit, a comparison circuit, and an execution circuit connected electrically. The voltage stabilizing circuit provides a stable reference voltage for the low-power tripping coil control circuit; the comparison circuit receives the reference voltage from the voltage stabilizing circuit and the voltage to be measured across the tripping coil, and generates a control signal by comparing the magnitudes of these two voltages; the execution circuit controls the on-off of the low-power tripping coil according to the control signal output by the comparison circuit.

[0006] Preferably, the voltage stabilizing circuit includes: a voltage reference chip U1.

[0007] Preferably, the comparison circuit includes: one end of a resistor R2 is respectively connected to the inverting input terminal 2 of a comparator U3 and one end of a resistor R7, one end of a resistor R4 is connected to the non-inverting input terminal 3 of the comparator U3, the power supply terminal 1 of the comparator U3 is respectively connected to the positive electrode of a capacitor C2 and one end of a capacitor C3, the ground terminal 4 of the comparator U3 is grounded, and the output terminal of the comparator U3 is connected to the other end of the resistor R7.

[0008] Preferably, the execution circuit includes: the anode of thyristor U2 is connected to one end of the release H1, the cathode of thyristor U2 is connected to one end of capacitor C4, and the control electrode of thyristor U2 is respectively connected to one end of resistor R3 and the other end of capacitor C4.

[0009] Preferably, the voltage regulation circuit further includes: pin 2 of voltage reference chip U1 is respectively connected to pin 1 of voltage reference chip U1 and one end of resistor R1, pin 3 of voltage reference chip U1 is connected to pin 4 of rectifier bridge D1, pin 3 of rectifier bridge D1 is respectively connected to the other end of resistor R1, the positive electrode of capacitor C1, and one end of resistor R5, the other end of resistor R5 is connected to one end of resistor R6, the other end of resistor R6 is connected to one end of resistor R8, and the other end of resistor R8 is grounded.

[0010] Preferably, the voltage reference chip U1 includes any one of REF5025AIDR, LM236D, LM385D, LM336B, REF1004I-2.5, and REF200AU.

[0011] Implementing the low-power release coil control circuit of the present invention has the following beneficial effects: By using a voltage regulation circuit, a comparison circuit, and an execution circuit connected electrically, the voltage regulation circuit provides a stable reference voltage for the low-power release coil control circuit; the comparison circuit receives the reference voltage from the voltage regulation circuit and the voltage to be measured across the release coil, and generates a control signal by comparing the magnitudes of these two voltages; the execution circuit controls the on / off of the low-power release coil according to the control signal output by the comparison circuit; by controlling the on / off of the release coil, the opening and closing of the circuit are realized to protect the circuit and equipment from abnormal conditions such as overload and short circuit; it has low power, is safe and reliable, and can be widely applied to fields such as energy storage systems, power systems, transportation, petrochemical industry, and electrical control. Description of the Drawings

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following-described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings. The present invention will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0013] Figure 1 is a schematic diagram of the connection between the release and the power supply in the low-power release coil control circuit of the present invention;

[0014] Figure 2 is a schematic diagram of the circuit composition of the low-power release coil control circuit of the present invention.

[0015] In the figure, 10 is a voltage stabilizing circuit, 20 is a comparison circuit, and 30 is an execution circuit. Specific implementation mode

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0017] It should be noted that if there are directional indications (such as up, down, left, right, front, back,...) involved in the embodiments of the present invention, then the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0018] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present invention, then the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0019] Please refer to Figure 1 , which is a schematic diagram of the connection between the release and the power supply in the low-power release coil control circuit of the present invention. As Figure 1 shown, the power supply needs to be turned on first every time the release is triggered. As Figure 1 shown, when the "KEY1" button is pressed, the output voltage of the power supply rises from 0V to 24V. According to the electromotive force formula: E = L×(△I÷△t), it can be known that the rate of change of current determines the rate of change of magnetic flux, the rate of change of magnetic flux determines the magnitude of the induced current, and the magnitude of the induced current affects the rate of change of current. Therefore, to make the shunt release burst out enough force to complete the tripping action, the release needs to be charged within the shortest time. In this system, the process of the power supply voltage rising from 0 to 24V is removed to reduce the charging time and store the small-power energy released by the power supply.

[0020] Please refer to Figure 2, is a schematic diagram of the circuit composition of the low-power trip coil control circuit of the present utility model. As Figure 2 shown, in the low-power trip coil control circuit provided by an embodiment of the present utility model, it at least includes a voltage stabilizing circuit 10, a comparison circuit 20, and an execution circuit 30 that are electrically connected. The voltage stabilizing circuit 10 provides a stable reference voltage for the low-power trip coil control circuit; the comparison circuit 20 receives the reference voltage from the voltage stabilizing circuit 10 and the voltage to be measured across the trip coil, and generates a control signal by comparing the magnitudes of these two voltages; the execution circuit 30 controls the on-off of the low-power trip coil according to the control signal output by the comparison circuit 20.

[0021] The voltage stabilizing circuit 10 includes: a voltage reference chip U1. Specifically, in implementation, the voltage stabilizing circuit 10 further includes: pin 2 of the voltage reference chip U1 is respectively connected to pin 1 of the voltage reference chip U1 and one end of a resistor R1, pin 3 of the voltage reference chip U1 is connected to pin 4 of a rectifier bridge D1, pin 3 of the rectifier bridge D1 is respectively connected to the other end of the resistor R1, the positive electrode of a capacitor C1, and one end of a resistor R5, the other end of the resistor R5 is connected to one end of a resistor R6, the other end of the resistor R6 is connected to one end of a resistor R8, and the other end of the resistor R8 is grounded.

[0022] Specifically, in implementation, the voltage reference chip U1 can but is not limited to include any one of REF5025AIDR, LM236D, LM385D, LM336B, REF1004I-2.5, REF200AU.

[0023] As a high-precision voltage reference chip, TI REF5025AIDR is characterized by low noise (3μVp-p at 0.1Hz to 10Hz), low temperature drift (3ppm / °C), and high precision (0.05%). It is suitable for high-precision data acquisition systems, can provide a stable and reliable voltage reference, and ensure the accuracy of measurement results.

[0024] LM series: such as LM236D, LM385D, etc. These chips are characterized by a wide operating current range, low power consumption, and high precision. The LM series voltage reference chips not only provide a stable voltage output but also can work stably within a wide voltage and current range, meeting the requirements of different application scenarios.

[0025] REF series voltage reference chips, such as REF1004I-2.5, REF200AU, etc., provide multiple output voltage options and have high precision and stability. They are particularly suitable for occasions that require a high-precision voltage reference, such as precision instruments, medical equipment, and communication networks.

[0026] The working principle of a voltage reference chip is mainly based on high-precision components such as resistors, capacitors, and temperature sensors, and realizes precise voltage control and compensation through specific circuit designs. Specifically, they generate a stable and precise voltage value through an internal circuit, and this voltage value does not change with the changes of the external environment (such as temperature, power supply voltage, etc.), thus serving as the voltage reference for other circuits and systems.

[0027] Generation of the reference voltage: Inside the voltage reference chip, there is one or more high-precision voltage sources, which can be Zener diode-based, temperature-compensated, or integrated reference source type. Through specific circuit designs, they generate a stable and precise reference voltage.

[0028] Temperature compensation: To eliminate the influence of temperature on the reference voltage, many voltage reference chips adopt temperature compensation technology. By integrating a temperature sensor and a feedback circuit inside the chip, the chip temperature is monitored in real time and the reference voltage value is automatically adjusted to ensure the stability of the output voltage at different temperatures.

[0029] Noise suppression: There are various electromagnetic interferences and noise sources in an electronic system, and these noises may affect the performance of the system. The voltage reference chip suppresses the influence of noise by adding a filtering circuit at its output end, providing a clearer signal output.

[0030] The voltage reference chip is the stabilizer of the entire control circuit, and it is responsible for providing an accurate and stable reference voltage. This reference voltage is the basis for subsequent circuits (comparison circuit 20 and execution circuit 30) to make comparisons and judgments. The voltage reference chip adopts precise circuit designs inside, such as bandgap reference circuits or Zener reference circuits. These designs can compensate for the influence of factors such as temperature and power supply voltage fluctuations on the output voltage, ensuring the high stability and accuracy of the output voltage.

[0031] In a bandgap reference circuit, the temperature characteristics of the base-emitter voltage of a transistor and the temperature characteristics of the collector current cancel each other out, thus realizing a reference voltage with zero temperature coefficient. The Zener reference provides a stable voltage output by combining a Zener diode with an operational amplifier or a voltage divider circuit. The output voltage of the voltage reference chip is generally from a few volts to dozens of volts, depending on the model and design.

[0032] During specific implementation, the comparison circuit 20 includes: one end of a resistor R2 is respectively connected to the inverting input terminal 2 of a comparator U3 and one end of a resistor R7, one end of a resistor R4 is connected to the non-inverting input terminal 3 of the comparator U3, the power supply terminal 1 of the comparator U3 is respectively connected to the positive electrode of a capacitor C2 and one end of a capacitor C3, the grounding terminal 4 of the comparator U3 is grounded, and the output terminal of the comparator U3 is connected to the other end of the resistor R7.

[0033] The comparison circuit 20 is the decision-maker in the control circuit. It receives the reference voltage from the voltage reference chip and the voltage to be measured (such as the voltage across the trip coil), and generates a control signal by comparing the magnitudes of these two voltages. The comparator U3 has two analog voltage input terminals (UIN+ and UIN-) and one digital status output terminal (UOUT). When UIN+ is greater than UIN-, UOUT outputs a high level; otherwise, it outputs a low level.

[0034] The working principle of the comparator is based on the open-loop high-gain characteristic of the operational amplifier (op-amp). In an ideal situation, when the input voltage difference exceeds a tiny dead zone, the output will quickly jump to the positive power supply voltage or the negative power supply voltage, thus clearly indicating the magnitude relationship of the input voltages. The comparator circuit is simple and has a fast response speed, making it very suitable for occasions that require rapid voltage magnitude judgment.

[0035] The execution circuit 30 includes: the anode of the thyristor U2 is connected to one end of the release H1, the cathode of the thyristor U2 is connected to one end of the capacitor C4, and the control electrode of the thyristor U2 is respectively connected to one end of the resistor R3 and the other end of the capacitor C4.

[0036] The thyristor U2 (Silicon Controlled Rectifier, abbreviated as SCR) is the executor in the control circuit. It controls the on / off of the low-power trip coil according to the control signal output by the comparator U3. The thyristor U2 is a high-power semiconductor device with a four-layer structure having three PN junctions, and has the advantages of small volume, high efficiency, good stability, etc. Its working principle is based on the unidirectional conductivity of the PN junction and the triggering effect of the control electrode.

[0037] When the control electrode (G) receives a high-level signal (i.e., the trigger signal) from the comparator and there is a forward voltage between the anode (A) and the cathode (K), the thyristor U2 will conduct, allowing current to pass through the trip coil. Conversely, when there is no trigger signal at the control electrode or the anode voltage is lower than the holding voltage, the thyristor will turn off, cutting off the current of the trip coil. This "small controls large" control characteristic of the thyristor makes it widely used in the field of power control.

[0038] The working principle of the low-power trip coil control circuit of the present utility model is:

[0039] The non-inverting terminal (B) of the comparator detects the power supply output voltage, and the inverting terminal (A) is connected to the reference voltage. When the power supply voltage is greater than the reference voltage, the thyristor is triggered to conduct, and then the release is triggered to operate. Conversely, when the power supply voltage is less than the reference voltage, the thyristor disconnects and the release does not operate. At the same time, capacitors C1, C2, and C3 act as energy storage components to provide a certain amount of energy for the thyristor to conduct and trigger the release, realizing the function of triggering the release with low power. When the current in the circuit exceeds the set value, the control circuit will start, energize the trip coil to generate a magnetic field, attract the iron core to move, thereby triggering the trip mechanism and disconnecting the circuit. This process is rapid and effective, capable of quickly cutting off the fault current and protecting the safety of the circuit and equipment.

[0040] The working process of the low-power trip coil control circuit of the present utility model is as follows:

[0041] The voltage reference chip first provides a stable reference voltage to the comparator. The comparator compares the voltage across the trip coil with the reference voltage in real time and outputs a control signal to the thyristor according to the comparison result. When the voltage across the trip coil exceeds the set value (i.e., the reference voltage), the comparator outputs a high-level signal to trigger the thyristor to conduct, thereby cutting off the current of the trip coil and realizing the protection action. Conversely, when the voltage is lower than the set value, the thyristor remains in the off state and the trip coil operates normally.

[0042] The low-power trip coil control circuit of the present utility model can be widely applied in fields such as power systems, transportation, petrochemical industry, and electrical control. In power systems, it can be used for the anti-pumping design of circuit breakers to prevent the circuit breaker from repeatedly closing under fault conditions, thus avoiding equipment damage and accident expansion. In the transportation field, the trip coil control circuit can also be used for the protection of various electrical equipment to ensure the safe operation of vehicles and equipment. In addition, in industries such as petrochemical, the trip coil control circuit also plays an important role in ensuring the safety of circuits and equipment during the production process.

[0043] Through the design of the above embodiments of the present utility model, its beneficial effects are as follows: By using a voltage stabilization circuit, a comparison circuit, and an execution circuit connected electrically, the voltage stabilization circuit provides a stable reference voltage for the low-power trip coil control circuit; the comparison circuit receives the reference voltage from the voltage stabilization circuit and the voltage to be measured across the trip coil, and generates a control signal by comparing the magnitudes of these two voltages; the execution circuit controls the on / off of the low-power trip coil according to the control signal output by the comparison circuit; by controlling the on / off of the trip coil, the opening and closing control of the circuit is realized to protect the circuit and equipment from being affected by abnormal conditions such as overload and short circuit; it has low power, is safe and reliable, and can be generally applicable to fields such as energy storage systems, power systems, transportation, petrochemical industry, and electrical control.

[0044] The present utility model is described according to specific embodiments, but those skilled in the art should understand that various changes and equivalent substitutions can be made without departing from the scope of the present utility model. In addition, in order to adapt to the specific circumstances of the technology of the present utility model, many modifications can be made to the present utility model without departing from its protection scope. Therefore, the present utility model is not limited to the specific embodiments disclosed herein, but includes all embodiments falling within the protection scope of the claims.

Claims

1. A low-power trip coil control circuit, characterized in that, Comprising: A voltage stabilizing circuit, a comparison circuit, and an execution circuit that are electrically connected. The voltage stabilizing circuit provides a stable reference voltage for the low-power trip coil control circuit. The comparison circuit receives the reference voltage from the voltage stabilizing circuit and the voltage to be measured across the trip coil, and generates a control signal by comparing the magnitudes of these two voltages. The execution circuit controls the on / off of the low-power trip coil according to the control signal output by the comparison circuit.

2. The low-power trip coil control circuit according to claim 1, wherein The voltage stabilizing circuit includes: a voltage reference chip U1.

3. The low-power trip coil control circuit according to claim 1, characterized in that, The comparison circuit includes: one end of a resistor R2 is connected to the inverting input terminal 2 of a comparator U3 and one end of a resistor R7 respectively, one end of a resistor R4 is connected to the non-inverting input terminal 3 of the comparator U3, the power supply terminal 1 of the comparator U3 is connected to the positive electrode of a capacitor C2 and one end of a capacitor C3 respectively, the ground terminal 4 of the comparator U3 is grounded, and the output terminal of the comparator U3 is connected to the other end of the resistor R7.

4. The low-power trip coil control circuit according to claim 1, wherein The execution circuit includes: the anode of a thyristor U2 is connected to one end of a trip device H1, the cathode of the thyristor U2 is connected to one end of a capacitor C4, and the control electrode of the thyristor U2 is connected to one end of a resistor R3 and the other end of the capacitor C4 respectively.

5. The low-power trip coil control circuit according to claim 2, wherein, The voltage stabilizing circuit further includes: pin 2 of the voltage reference chip U1 is connected to pin 1 of the voltage reference chip U1 and one end of a resistor R1 respectively, pin 3 of the voltage reference chip U1 is connected to pin 4 of a rectifier bridge D1, pin 3 of the rectifier bridge D1 is connected to the other end of the resistor R1, the positive electrode of a capacitor C1, and one end of a resistor R5 respectively, the other end of the resistor R5 is connected to one end of a resistor R6, the other end of the resistor R6 is connected to one end of a resistor R8, and the other end of the resistor R8 is grounded.

6. The low-power trip coil control circuit according to claim 2, wherein The voltage reference chip U1 includes any one of REF5025AIDR, LM236D, LM385D, LM336B, REF1004I-2.5, REF200AU.

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