Insulation and voltage resistance detection circuit

Abstract

An insulation and voltage resistance detection circuit comprises an input port which is connected with a rectifier diode through a resistance network and is used for carrying out current limiting and voltage dividing processing on an input signal; the rectifying circuit is used for carrying out full-wave rectification on an input signal by utilizing a plurality of diodes and outputting stable direct-current voltage; the filter circuit comprises a plurality of filter capacitors and is used for carrying out smooth filtering on the rectified direct-current voltage and providing stable output voltage; the optical coupler U1 is used for realizing electrical isolation between an input signal and an output power supply and avoiding high-voltage or noise conduction; the current limiting circuit comprises a current limiting resistor and is used for controlling the current passing through the optocoupler or the LED and protecting the device; by introducing a multi-stage resistor current limiting circuit, a diode rectification circuit, a filter capacitor circuit and an optical coupler isolation circuit, efficient power supply control is realized.

Description

Technical Field:

[0001] This patent relates to the field of power supply control, and specifically to an insulation withstand voltage detection circuit suitable for intelligent power supply control circuits that provide input signal protection, rectification, filtering, optocoupler isolation, and output stability. This circuit can be used for low-voltage power supply control, signal isolation, and provides stable output, and is widely applied in signal control, industrial automation, and sensor applications. Background technology:

[0002] Electrical drive products typically require insulation withstand voltage testing to meet safety regulations. This is usually done using an insulation withstand voltage tester, which offers good results but has significant drawbacks: firstly, it requires specialized testing equipment to short-circuit the high-voltage terminals; secondly, it cannot provide real-time monitoring. If an insulation problem occurs during operation, the customer will not be aware of it because the device is still running, potentially leading to safety issues.

[0003] In existing power supply control circuits, input signal protection, rectification, and output stabilization are crucial. This is especially true in industrial automation control, where circuits are susceptible to noise interference, leading to unstable output. Furthermore, input signals often need to be isolated from the output to prevent damage to components from reverse current or high-voltage surges. Therefore, designing a power supply control circuit that incorporates input protection, rectification, filtering, and optocoupler isolation functions can effectively improve the reliability and stability of the system. Utility Model Content

[0004] This patent provides an intelligent power control circuit with the following features:

[0005] The input ports (X2, X3, X4) are connected to rectifier diodes (D4, D5, D6, D7) through a resistor network for current limiting and voltage division of the input signal.

[0006] The rectifier circuit uses multiple diodes (D4, D5, D6, D7) to perform full-wave rectification on the input signal and output a stable DC voltage.

[0007] The filter circuit, including multiple filter capacitors (C29, C30, C31), is used to smooth and filter the rectified DC voltage to provide a stable output voltage.

[0008] Optocoupler U1 is used to achieve electrical isolation between the input signal and the output power supply to prevent high voltage or noise conduction;

[0009] The current limiting circuit, including the current limiting resistor R15, is used to control the current through the optocoupler or LED to protect the device.

[0010] Preferably, the optocoupler of the circuit also has a working status indication function, which is indicated by the light-emitting diode of the optocoupler when the circuit is working normally.

[0011] Preferably, the filter circuit further includes a capacitor C29 for further stabilizing the output power supply, ensuring the stability and continuity of the output voltage.

[0012] Preferably, the diode D8 is used to protect the light-emitting diode U1 and prevent reverse current from damaging the LED.

[0013] Input port protection function: The input signal is voltage divided and current limited by a multi-stage resistor network to ensure that the input signal is properly processed before entering the circuit.

[0014] Rectification and filtering functions: The rectifier circuit is constructed using multiple diodes and filtered by capacitors to ensure the stability of the DC voltage at the output terminal.

[0015] Optocoupler isolation function: Optocouplers are used to electrically isolate the input and output, improving the circuit's anti-interference ability and preventing high voltage surges.

[0016] Stable output: The current-limiting resistor and filter capacitor ensure stable output voltage, making it suitable for stable power supply to subsequent equipment. Attached image description:

[0017] Appendix Figure 1 This is a detailed schematic diagram of the circuit in this patent. Detailed implementation method:

[0018] Combined with appendix Figure 1 The specific implementation method of this patent is as follows:

[0019] Input ports (X2, X3, X4)

[0020] This circuit has input ports X2, X3, and X4, each used to receive different input signals. Each input port uses a resistor network for current limiting and voltage division. For example, X4 is connected in series with resistors R2, R5, R7, and R9; X2 is connected in series with resistors R3, R11, R10, and R12; and X3 is directly connected to the subsequent stage of the circuit. The purpose of these resistors is to limit the current of the input signal and prevent excessive current from directly entering the subsequent circuit, thus avoiding damage to other components.

[0021] Rectifier and protection circuit

[0022] After the signal is processed by the resistor network, it enters the rectifier circuit composed of diodes D4, D5, D6, and D7. Each diode operates with unidirectional conduction characteristics, allowing current to flow in a specified direction and preventing reverse current from affecting the circuit. These diodes form a full-wave rectifier circuit, converting AC or pulsating signals into DC signals, providing a stable DC voltage for subsequent filtering and output.

[0023] Filtering circuit

[0024] In the circuit, C29, C30, and C31 are filter capacitors, located after the rectifier circuit. They are used to smooth the rectified DC signal and suppress voltage fluctuations and noise generated by diode rectification. Specifically, C30 and C31 smooth the rectified current to ensure the stability of the output voltage; C29 further stabilizes the power supply to prevent power instability from interfering with subsequent circuits.

[0025] Optical isolation

[0026] Another innovation of this patent lies in the introduction of an optocoupler isolation element U1. Optocoupler isolation isolates the input signal from the output terminal via optical signals, achieving electrical isolation. The optocoupler internally contains a light-emitting diode (LED) and a phototransistor. When the input signal passes through the LED, the phototransistor is turned on through light transmission. The advantage of this is that high voltage or noise at the input terminal will not be transmitted to the output terminal, greatly improving the circuit's anti-interference capability. Furthermore, the optocoupler can also be used as a status indicator; when the circuit is working normally, the LED will light up to indicate the circuit's operating status.

[0027] Current limiting and output circuit

[0028] The final output is connected to the X1 port via a current-limiting resistor R15 and a filter capacitor C29. R15 limits the current flowing through the optocoupler or LED, preventing damage to these components due to excessive current and ensuring their lifespan. Simultaneously, the output signal, after further filtering by C29, provides a more stable power output, suitable for supplying power to subsequent circuits or providing control signals.

[0029] LED and diode D8

[0030] This patented circuit also includes a light-emitting diode (LED) U1 and a pre-stage protection diode D8. The function of diode D8 is to protect the LED from damage when the current in the input signal reverses. When the circuit is working, the LED U1 will light up, serving as an indicator of the working status.

[0031] This invention achieves efficient power supply control by introducing multi-stage resistor current limiting, diode rectification, filter capacitors, and optocoupler isolation circuits. This circuit provides a stable DC power output, is suitable for various application scenarios, and has advantages such as strong noise suppression, strong anti-interference capability, and wide applicability.

Claims

1. An insulation withstand voltage detection circuit, characterized in that, include: The input ports (X2, X3, X4) are connected to rectifier diodes (D4, D5, D6, D7) through a resistor network for current limiting and voltage division of the input signal. The rectifier circuit uses multiple rectifier diodes (D4, D5, D6, D7) to perform full-wave rectification on the input signal and output a stable DC voltage; the filter circuit includes multiple filter capacitors (C29, C30, C31) to smooth and filter the rectified DC voltage and provide a stable output voltage. Optocoupler U1 is used to achieve electrical isolation between the input signal and the output power supply to prevent high voltage or noise conduction; current limiting circuit, including current limiting resistor R15, is used to control the current through the optocoupler or LED to protect the device.

2. The insulation withstand voltage detection circuit as described in claim 1, characterized in that, The optocoupler of the circuit also has a working status indication function. When the circuit is working normally, the light-emitting diode of the optocoupler will illuminate to indicate the status.

3. An insulation withstand voltage testing circuit as described in claim 1 or 2, characterized in that, The filter circuit further includes a capacitor C29 for further stabilizing the output power supply, ensuring the stability and continuity of the output voltage.

4. The insulation withstand voltage detection circuit as described in claim 1, characterized in that, The diode D8 is used to protect the light-emitting diode U1 and prevent reverse current from damaging the LED.

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