Simple low-cost AC voltage detection protection device

Abstract

The invention discloses a simple low-cost alternating-current voltage detection protection device which comprises a voltage sampling unit, a detection control unit, a fault protection unit and an auxiliary power supply unit. The preceding stage of the device adopts isolation, voltage reduction, rectification, filtering and resistance voltage division to collect voltage signals, and the backward stage adopts an analog-to-digital converter (ADC) and a single-chip microcomputer circuit to analyze, calculate and detect a voltage true effective value through software, send a control signal to trigger a protection mechanism and cut off or adjust power supply, so that electrical equipment damage and electric power accidents are prevented. The device is simple, reliable, mature and stable in circuit design, well solves the problems of complex circuit structure, high material cost, low measurement precision, slow response speed, poor environmental adaptability and the like, realizes the optimal design of the AC voltage detection protection device, is widely applied to the civil and industrial production field, and has a good market application prospect.

Description

Technical Field

[0001] The present invention relates to the field of AC voltage detection and protection, and in particular to a simple and low-cost AC voltage detection and protection device. Background Art

[0002] In modern electrical systems, protection circuits play a vital role, ensuring the stable operation and safety of electrical equipment. AC voltage detection and protection devices precisely measure the AC supply voltage, enabling quick and accurate detection of AC power anomalies. This allows them to trigger protection mechanisms, cutting off or adjusting the power supply, and preventing damage to electrical equipment and electrical accidents.

[0003] In recent years, due to technological advancements and economic development, more and more civil and industrial electrical equipment has been widely used. Therefore, ensuring the stable operation and safety of electrical equipment is particularly important. At the same time, due to the control of material costs by various manufacturers, a simple and low-cost AC voltage detection and protection device is needed to meet market demand. Compared with the AC voltage detection and protection devices currently available on the market, this device has the following advantages:

[0004] 1) The circuit structure is simple;

[0005] 2) Low material cost;

[0006] 3) High detection accuracy (true effective value detection);

[0007] 4) Fast response speed;

[0008] 5) Good environmental adaptability;

[0009] The AC voltage detection and protection devices in the prior art are difficult to meet the above requirements.

[0010] In view of this, the present invention is proposed. Summary of the Invention

[0011] The purpose of the present invention is to provide a simple and low-cost AC voltage detection and protection device to meet the high cost-performance requirements of AC voltage detection and protection devices in modern life and production.

[0012] The purpose of the present invention is achieved through the following technical solutions:

[0013] The simple and low-cost AC voltage detection and protection device of the present invention includes a voltage sampling unit, a detection and control unit, a fault protection unit, and an auxiliary power supply unit;

[0014] The voltage sampling unit includes an isolated step-down circuit, a rectifier circuit, a filter circuit, and a voltage sampling circuit. Its front end is connected to the AC input, and its back end is connected to the detection control unit. It completes AC input voltage sampling by converting the AC input signal into a pulsating DC voltage signal.

[0015] The detection control unit includes a voltage detection circuit and an analysis control circuit. The front end is connected to the voltage sampling unit and the back end is connected to the fault protection unit. It is used to detect the true effective value of the AC input sampling voltage and send a control signal to the fault protection unit after analysis and judgment.

[0016] The fault protection unit cuts off or adjusts the power supply according to the control signal to prevent damage to electrical equipment and power accidents;

[0017] The auxiliary power supply unit is used to provide a stable DC power supply to ensure the normal operation of the device.

[0018] Compared with existing technologies, the simple, low-cost AC voltage detection and protection device provided by the present invention solves problems such as complex circuit structure, high material costs, low measurement accuracy, slow response speed, and poor environmental adaptability, achieving an optimized design for the AC voltage detection and protection device. This AC voltage detection and protection device has a simple, reliable, mature, and stable circuit design, effectively resolving the aforementioned issues. It offers advantages such as a simple circuit structure, low material costs, high detection accuracy, fast response speed, good environmental adaptability, and ease of maintenance, and has promising market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A block diagram of a simple and low-cost AC voltage detection and protection device provided by an embodiment of the present invention;

[0020] Figure 2 This is a system principle block diagram of a simple and low-cost AC voltage detection and protection device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. It is obvious that the described embodiments are only some of the embodiments of the present invention, not all of them, and do not constitute a limitation of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] First, the following terms may be used in this article:

[0023] The terms "include," "comprises," "contains," "has," or other similar expressions should be interpreted as non-exclusive. For example, "including certain technical features (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products, or manufactured articles)" should be interpreted as including not only the technical features explicitly listed, but also other technical features known in the art that are not explicitly listed.

[0024] The contents not described in detail in the examples of the present invention belong to the prior art known to those skilled in the art. If specific conditions are not specified in the examples of the present invention, the methods are carried out according to conventional conditions in the art or the conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments used in the examples of the present invention are not specified, they are all conventional products that can be purchased commercially.

[0025] The simple and low-cost AC voltage detection and protection device of the present invention is characterized by comprising a voltage sampling unit, a detection and control unit, a fault protection unit, and an auxiliary power supply unit;

[0026] The voltage sampling unit includes an isolated step-down circuit, a rectifier circuit, a filter circuit, and a voltage sampling circuit. Its front end is connected to the AC input, and its back end is connected to the detection control unit. It completes AC input voltage sampling by converting the AC input signal into a pulsating DC voltage signal.

[0027] The detection control unit includes a voltage detection circuit and an analysis control circuit. The front end is connected to the voltage sampling unit and the back end is connected to the fault protection unit. It is used to detect the true effective value of the AC input sampling voltage and send a control signal to the fault protection unit after analysis and judgment.

[0028] The fault protection unit cuts off or adjusts the power supply according to the control signal to prevent damage to electrical equipment and power accidents;

[0029] The auxiliary power supply unit is used to provide a stable DC power supply to ensure the normal operation of the device.

[0030] The fault protection unit includes a thyristor and a drive circuit;

[0031] The drive circuit controls the thyristor according to the state of the control signal, cuts off or adjusts the power supply, and prevents damage to electrical equipment and power accidents.

[0032] The control end of the drive circuit is connected to the detection control unit, the power end of the thyristor is connected to the AC input and the power-consuming equipment respectively, and the detection control unit sends a control signal to the drive circuit.

[0033] The auxiliary power supply unit includes a switching power supply module and a voltage regulating circuit, which is used to provide a stable DC power supply to ensure the normal operation of the device.

[0034] The front end of the auxiliary power supply unit is connected to the AC input, and the rear end is connected to the detection control unit and the fault protection unit respectively. The AC input voltage is initially stabilized by the switching power supply module and then further stabilized by the linear voltage adjustment circuit to output a stable DC voltage to supply the detection control unit and the fault protection unit.

[0035] In summary, the simple and low-cost AC voltage detection and protection device of the embodiment of the present invention solves the problems of complex circuit structure, high material cost, low measurement accuracy, slow response speed, and poor environmental adaptability through the simple and low-cost AC voltage detection and protection device, realizes the optimized design of the AC voltage detection and protection device, and reduces the cost of the device at the same time.

[0036] This device boasts a simple circuit structure, high detection accuracy, fast response speed, and low material cost. Its front-end utilizes isolation, voltage reduction, rectification, filtering, and resistor voltage division to acquire voltage signals. The back-end utilizes an analog-to-digital converter (ADC) and a single-chip microcomputer circuit to analyze and calculate the true RMS value of the detected voltage through software, sending a control signal to trigger a protection mechanism that cuts off or adjusts the power supply, thereby preventing damage to electrical equipment and electrical accidents. The device's circuit design is simple, reliable, mature, and stable, effectively addressing issues such as complex circuit structure, high material cost, low measurement accuracy, slow response speed, and poor environmental adaptability. This optimizes the design of an AC voltage detection and protection device, making it widely applicable to both civilian and industrial production applications and promising market prospects.

[0037] In order to more clearly demonstrate the technical solutions and technical effects provided by the present invention, the technical solutions provided by the embodiments of the present invention are described in detail below with reference to specific embodiments.

[0038] Example 1

[0039] like Figure 1 As shown in the figure, the simple and low-cost AC voltage detection and protection device consists of a voltage sampling unit, a detection and control unit, a fault protection unit, and an auxiliary power supply unit. It is used to detect the AC power supply voltage of electrical equipment. If power supply abnormality is found, the protection mechanism is triggered in time to cut off or adjust the power supply to prevent damage to electrical equipment and power accidents.

[0040] Specific as Figure 2The device, shown in Figure 1, is a simple, low-cost AC voltage detection and protection device. It includes a voltage sampling unit, a detection and control unit, a fault protection unit, and an auxiliary power supply unit. The AC input is simultaneously supplied to the voltage sampling unit, the fault protection unit, and the auxiliary power supply unit. The voltage sampling unit isolates the AC input, steps down the voltage, rectifies it, filters it, and divides it with resistors to produce a pulsating DC voltage signal. The detection and control unit detects and determines the DC voltage signal, then sends a control signal to the fault protection unit, triggering a protection mechanism that cuts off or adjusts the power supply to prevent damage to electrical equipment and electrical accidents. The auxiliary power supply unit provides a stable DC power supply to ensure the normal operation of the device.

[0041] The voltage sampling unit includes an isolation step-down circuit, a rectifier circuit, a filter circuit, and a voltage sampling circuit;

[0042] The isolated step-down circuit is composed of an isolated step-down transformer, which has the functions of electrical isolation and voltage conversion. The transformer adopts a high-winding, low-power, EI type transformer, which has the advantages of small size, light weight, low loss, strong environmental adaptability, low price, and easy procurement.

[0043] The rectifier circuit consists of a full-bridge circuit composed of 1N4007 rectifier diodes, which converts the AC input signal into a pulsating DC signal. Because the 1N4007 diode is known for its high reverse recovery time, low forward voltage drop, and high current capacity, it has multiple advantages in improving circuit efficiency, stability, and reliability.

[0044] The filtering circuit is composed of a low-pass filter composed of RC parallel connections to filter out high-frequency noise. The circuit structure is simple and has a significant effect in improving signal quality. In addition, the resistors and capacitors used are widely available in the market, low in price, and easy to purchase.

[0045] The voltage sampling circuit is composed of a resistor divider circuit, which is used to collect voltage signals. In high-precision measurements, even small errors in resistance can lead to significant deviations in the final measurement results. Therefore, this circuit uses high-precision, low-temperature drift resistors to minimize the impact of resistance accuracy and temperature coefficient on the sampled signal.

[0046] The detection control unit includes a signal detection circuit and an analysis control circuit;

[0047] The signal detection circuit is composed of an analog-to-digital converter (ADC), which converts the DC signal transmitted by the voltage sampling unit into a digital signal and transmits it to the analysis and control circuit. This ADC uses a successive approximation register (SAR) ADC, which excels in conversion speed and efficiency. In terms of cost-effectiveness, the SAR ADC has a high level of integration and mature manufacturing processes, resulting in relatively low production costs and greater cost control.

[0048] The analysis and control circuit is composed of a single-chip microcomputer and its peripheral circuits. Its function is to analyze and calculate the digital signal transmitted by the signal detection circuit to obtain the true effective value of the AC input voltage, and send a control signal to the fault protection unit after judgment. Since there is a certain degree of pollution in the power grid, the true effective value detection can better reflect the actual situation of the AC input voltage, so as to make an accurate judgment. This circuit uses software to detect the true effective value of AC power. Compared with the pure hardware circuit implementation, it has the following advantages: 1) The circuit is simpler. Compared with the pure hardware circuit, this solution only requires the minimum system of the single-chip microcomputer to implement, and the peripheral devices are relatively few; 2) The material cost is low. Compared with the true effective value detection chip AD637 on the market, it is only one-tenth of its cost;

[0049] The fault protection unit includes a thyristor and a driving circuit thereof;

[0050] The thyristor is composed of a bidirectional thyristor or two single-phase thyristors connected in reverse parallel, and is used to control the AC input voltage. Compared with the relay circuit, it has the advantages of fast response, no contact, small size and high efficiency;

[0051] The driving circuit is composed of a pulse transformer and discrete components, and is used to drive the thyristor to control the connection or disconnection of the AC power. The circuit structure is simple and the anti-interference ability is strong.

[0052] The auxiliary power supply unit includes a switching power supply module and a voltage adjustment circuit;

[0053] The switching power supply module adopts a wide-range input AC / DC switching module, which is used to ensure that a stable DC voltage can be output under a wide range of AC input;

[0054] The voltage adjustment circuit uses a three-terminal integrated voltage regulator chip, which is used to further reduce the ripple (rms) and peak-to-peak (pp) of the DC output through linear series adjustment, making it have strong anti-interference ability and ensuring the stable operation of the detection circuit;

[0055] In summary, the present invention utilizes isolation, voltage reduction, rectification, filtering, and resistor voltage division in the front-end to acquire voltage signals. The back-end utilizes an analog-to-digital converter (ADC) and a single-chip microcomputer circuit to analyze and calculate the true RMS value of the detected voltage through software and transmit a control signal to a fault protection unit. This unit triggers a protection mechanism, cutting off or adjusting the power supply, thereby preventing damage to electrical equipment and electrical accidents. This device boasts a simple, reliable, mature, and stable circuit design, effectively addressing issues such as complex circuit structure, high material costs, low measurement accuracy, slow response speed, and poor environmental adaptability, achieving an optimized design for AC voltage detection and protection devices. This device is widely applicable to both civilian and industrial production applications and has promising market prospects.

[0056] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims. The information disclosed in the background technology section of this article is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as an admission or any form of implication that the information constitutes prior art already known to those skilled in the art.

Claims

1. A simple and low-cost AC voltage detection and protection device, characterized in that: It includes voltage sampling unit, detection control unit, fault protection unit and auxiliary power supply unit; The voltage sampling unit includes an isolated step-down circuit, a rectifier circuit, a filter circuit, and a voltage sampling circuit. Its front end is connected to the AC input, and its back end is connected to the detection control unit. It completes AC input voltage sampling by converting the AC input signal into a pulsating DC voltage signal. The detection control unit includes a voltage detection circuit and an analysis control circuit. The front end is connected to the voltage sampling unit and the back end is connected to the fault protection unit. It is used to detect the true effective value of the AC input sampling voltage and send a control signal to the fault protection unit after analysis and judgment. The fault protection unit cuts off or adjusts the power supply according to the control signal to prevent damage to electrical equipment and power accidents; The auxiliary power supply unit is used to provide a stable DC power supply to ensure the normal operation of the device.

2. The simple and low-cost AC voltage detection and protection device according to claim 1 is characterized in that: The fault protection unit includes a thyristor and a drive circuit; The drive circuit controls the thyristor according to the state of the control signal, cuts off or adjusts the power supply, and prevents damage to electrical equipment and power accidents.

3. The simple and low-cost AC voltage detection and protection device according to claim 2 is characterized in that: The control end of the drive circuit is connected to the detection control unit, the power end of the thyristor is connected to the AC input and the power-consuming equipment respectively, and the detection control unit sends a control signal to the drive circuit.

4. The simple and low-cost AC voltage detection and protection device according to claim 1 is characterized in that: The auxiliary power supply unit includes a switching power supply module and a voltage regulating circuit, which is used to provide a stable DC power supply to ensure the normal operation of the device.

5. The simple and low-cost AC voltage detection and protection device according to claim 4, characterized in that: The front end of the auxiliary power supply unit is connected to the AC input, and the rear end is connected to the detection control unit and the fault protection unit respectively. The AC input voltage is initially stabilized by the switching power supply module and then further stabilized by the linear voltage adjustment circuit to output a stable DC voltage to supply the detection control unit and the fault protection unit.

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