CN204202773U - A kind of high-frequency and high-voltage power supply temperature sensing circuit - Google Patents

Abstract

The utility model discloses a high-frequency high-voltage power supply temperature detection circuit, which includes a bridge circuit and an amplifier circuit. The bridge circuit includes resistors R1, R2, R4 and R5. The amplifier circuit includes amplifier IC1, chip IC4, and amplifier IC2. , amplifier IC3, amplifier IC5 and amplifier IC6. The system circuit of the utility model uses a plurality of LM358 amplifiers and AD620 instrument amplifiers to amplify the sampling signal in multiple stages, so that the amplification factor of the signal is more than 30 times, and the HCNR201 optical coupler is used for photoelectric isolation, which increases the anti-interference performance. The temperature signal is converted into a voltage signal by using a bridge structure, which effectively eliminates the error caused by the resistance itself and improves the accuracy of the circuit. Using this structure for temperature detection of high-frequency and high-voltage power supplies has high sensitivity, high detection accuracy, The advantage of good linear monitoring effect.

Description

A high-frequency high-voltage power supply temperature detection circuit

technical field

The utility model relates to a high-voltage power supply, in particular to a high-frequency high-voltage power supply temperature detection circuit with high sensitivity and high precision.

Background technique

High-frequency high-voltage power supply is a commonly used power supply in industrial production. It is widely used in electrostatic dust removal, oil fume purification and other fields. Generally, high-frequency high-voltage power supply is installed on the top of the tower of such equipment, and the ambient temperature around it is often very high. , especially in hot summer, when the ambient temperature reaches more than 40 degrees, the power supply itself will generate a lot of heat when it is working. The step-up transformer in the high-frequency high-voltage power supply also has high temperature requirements. When the high-voltage power supply is in a high-temperature state, it will accelerate the aging of the power supply. What's more, it may directly burn the power supply. The traditional high-frequency high-voltage power supply temperature detection circuit has low precision and poor sensitivity, and cannot effectively perform linear detection.

Utility model content

The purpose of this utility model is to provide a high-sensitivity, high-precision high-frequency high-voltage power supply temperature detection circuit to solve the problems raised in the above-mentioned background technology.

In order to achieve the above object, the utility model provides the following technical solutions:

A high-frequency high-voltage power supply temperature detection circuit, including a bridge circuit and an amplifier circuit, the bridge circuit includes a resistor R1, a resistor R2, a resistor R4 and a resistor R5, and the amplifier circuit includes an amplifier IC1, a chip IC4, an amplifier IC2, amplifier IC3, amplifier IC5 and amplifier IC6;

One end of resistor R1 is connected to resistor R2 and power supply U1, the other end of resistor R1 is connected to resistor R4, the other end of resistor R4 is connected to resistor R5 and resistor R6, the other end of resistor R2 is connected to resistor R3 and resistor R7, and the other end of resistor R3 is connected to The other end of resistor R5 is grounded, the other end of resistor R7 is connected to pin 2 of amplifier IC1, pin 1 of amplifier IC1 is connected to resistor R8, the other end of resistor R8 is connected to pin 8 of amplifier IC1, and pin 3 of amplifier IC1 Connect the other end of resistor R6, pin 5 of amplifier IC1 is grounded, pin 6 of amplifier IC1 is connected to pin 2 of amplifier IC2, pin 7 of amplifier IC1 is connected to power supply U1, pin 1 of amplifier IC2 is connected to resistor R9 and capacitor C1, the other end of resistor R9 is connected to resistor R10, the other end of capacitor C1 and pin 5 of amplifier IC2, pin 4 of amplifier IC2 is connected to power supply U1, pin 3 of amplifier IC2 is grounded, and the other end of resistor R10 is connected to capacitor C2 1 pin of amplifier IC3 and pin 3 of chip IC4, pin 2 of amplifier IC3 is connected to pin 3 of amplifier IC3 and grounded, pin 4 of amplifier IC3 is connected to power supply U1, pin 5 of amplifier IC3 is connected to resistor R11 and pin 1 of chip IC4, the other end of resistor R11 is connected to the other end of resistor C2, pin 2 of chip IC4 is connected to power supply U1, pin 4 of chip IC4 is grounded, pin 5 of chip IC4 is connected to pin 2 of amplifier IC5 6 pins of chip IC4 are connected to 12 pins of amplifier IC5, resistor R12 and capacitor C3, 4 pins of amplifier IC5 are connected to power supply U1, 3 pins of amplifier IC5 are grounded, 5 pins of amplifier IC5 are connected to amplifier IC6 2 pins, resistor R12 and capacitor C3, pin 1 of amplifier IC6 is connected to resistor R13 and capacitor C4, pin 4 of amplifier IC6 is connected to power supply U1, pin 3 of amplifier IC6 is grounded, pin 5 of amplifier IC6 is connected to resistor R14 , a resistor R12 and a capacitor C3, the other end of the resistor R14 is connected to the capacitor C5, the cathode of the diode T1 and the output Temp-out, the anode of the diode T1 is connected to the other end of the capacitor C5 and grounded.

As a preferred solution of the utility model: the amplifiers IC2, IC3, IC5 and IC6 are LM358 amplifiers, the amplifier IC1 is an AD620 instrument amplifier, and the chip IC4 is an HCRN201 optocoupler.

As a preferred solution of the present utility model: the power supply U1 is 12V direct current.

As a preferred solution of the present invention: the resistor R5 is a PT100 thermistor, and the resistance of the resistor R3 is 100 ohms.

Compared with the prior art, the beneficial effect of the utility model is: the circuit uses multiple LM358 amplifiers and AD620 instrument amplifiers to perform multi-stage amplification of the sampling signal, so that the amplification factor of the signal is more than 30 times, and the HCNR201 optical coupling is used The device is photoelectrically isolated, which increases the anti-interference performance. The temperature signal is converted into a voltage signal by using a bridge structure, which effectively eliminates the error caused by the resistance itself and improves the accuracy of the circuit. Using this structure for high-frequency high-voltage power supply The temperature detection has the advantages of high sensitivity, high detection accuracy and good linear monitoring effect.

Description of drawings

Fig. 1 is a circuit diagram of a high-frequency high-voltage power supply temperature detection circuit;

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Please refer to Fig. 1, in the embodiment of the utility model, a kind of high-frequency high-voltage power supply temperature detection circuit includes a bridge circuit and an amplifying circuit, the bridge circuit includes a resistor R1, a resistor R2, a resistor R4 and a resistor R5, and the amplifying circuit includes an amplifier IC1, chip IC4, amplifier IC2, amplifier IC3, amplifier IC5 and amplifier IC6;

One end of resistor R1 is connected to resistor R2 and power supply U1, the other end of resistor R1 is connected to resistor R4, the other end of resistor R4 is connected to resistor R5 and resistor R6, the other end of resistor R2 is connected to resistor R3 and resistor R7, and the other end of resistor R3 is connected to The other end of resistor R5 is grounded, the other end of resistor R7 is connected to pin 2 of amplifier IC1, pin 1 of amplifier IC1 is connected to resistor R8, the other end of resistor R8 is connected to pin 8 of amplifier IC1, and pin 3 of amplifier IC1 Connect the other end of resistor R6, pin 5 of amplifier IC1 is grounded, pin 6 of amplifier IC1 is connected to pin 2 of amplifier IC2, pin 7 of amplifier IC1 is connected to power supply U1, pin 1 of amplifier IC2 is connected to resistor R9 and capacitor C1, the other end of resistor R9 is connected to resistor R10, the other end of capacitor C1 and pin 5 of amplifier IC2, pin 4 of amplifier IC2 is connected to power supply U1, pin 3 of amplifier IC2 is grounded, and the other end of resistor R10 is connected to capacitor C2 1 pin of amplifier IC3 and pin 3 of chip IC4, pin 2 of amplifier IC3 is connected to pin 3 of amplifier IC3 and grounded, pin 4 of amplifier IC3 is connected to power supply U1, pin 5 of amplifier IC3 is connected to resistor R11 and pin 1 of chip IC4, the other end of resistor R11 is connected to the other end of resistor C2, pin 2 of chip IC4 is connected to power supply U1, pin 4 of chip IC4 is grounded, pin 5 of chip IC4 is connected to pin 2 of amplifier IC5 6 pins of chip IC4 are connected to 12 pins of amplifier IC5, resistor R12 and capacitor C3, 4 pins of amplifier IC5 are connected to power supply U1, 3 pins of amplifier IC5 are grounded, 5 pins of amplifier IC5 are connected to amplifier IC6 2 pins, resistor R12 and capacitor C3, pin 1 of amplifier IC6 is connected to resistor R13 and capacitor C4, pin 4 of amplifier IC6 is connected to power supply U1, pin 3 of amplifier IC6 is grounded, pin 5 of amplifier IC6 is connected to resistor R14 , a resistor R12 and a capacitor C3, the other end of the resistor R14 is connected to the capacitor C5, the cathode of the diode T1 and the output Temp-out, the anode of the diode T1 is connected to the other end of the capacitor C5 and grounded.

Amplifiers IC2, IC3, IC5 and IC6 are LM358 amplifiers, said amplifier IC1 is an AD620 instrument amplifier, and said chip IC4 is a HCRN201 optocoupler.

The power supply U1 is 12V direct current.

The resistor R5 is a PT100 thermistor, and the resistance of the resistor R3 is 100 ohms.

The working principle of the utility model is: when the ambient temperature is 0 degrees centigrade, the resistance value of the thermistor R5 is 100 ohms, and at this moment, the voltage of pin 2 and pin 3 of the amplifier IC1 of the flow direction meter is the same, and the output Temp-out is 0, as the measured temperature rises, the resistance of the thermistor R5 increases, and at this time the voltage flowing to pin 2 and pin 3 of the instrumentation amplifier IC1 is different, by detecting the magnitude of the voltage difference, that is It can be known that the temperature detected by PT100 is difficult to measure directly because the collected voltage difference signal is very small, so multiple LM358 amplifiers and AD620 instrument amplifiers are used to amplify the sampling signal with multiple poles, and HCNR201 optical coupling is used The device is photoelectrically isolated, so that the magnification of the signal is more than 30 times, and the change of the measured temperature can be accurately detected, and the measured output Temp-out voltage and temperature have a good linear relationship. Through the external processor, the The test results are reflected to the user.

Claims (4)

1. a high-frequency and high-voltage power supply temperature sensing circuit, comprises bridge diagram and multipole amplifying circuit; It is characterized in that, described bridge diagram comprises resistance R1, resistance R2, resistance R4 and resistance R5, and described multipole amplifying circuit comprises amplifier IC1, chip IC 4, amplifier IC2, amplifier IC3, amplifier IC5 and amplifier IC6;

One end contact resistance R2 of resistance R1 and power supply U1, the other end contact resistance R4 of resistance R1, the other end contact resistance R5 of resistance R4 and resistance R6, the other end contact resistance R3 of resistance R2 and resistance R7, the other end of the other end contact resistance R5 of resistance R3 ground connection, the other end of resistance R7 connects 2 pins of amplifier IC1, the 1 pin contact resistance R8 of amplifier IC1, the other end of resistance R8 connects 8 pins of amplifier IC1, the other end of the 3 pin contact resistance R6 of amplifier IC1, the 5 pin ground connection of amplifier IC1, 6 pins of amplifier IC1 connect 2 pins of amplifier IC2, 7 pins of amplifier IC1 connect power supply U1, the 1 pin contact resistance R9 of amplifier IC2 and electric capacity C1, the other end contact resistance R10 of resistance R9, the other end of electric capacity C1 and 5 pins of amplifier IC2, 4 pins of amplifier IC2 connect power supply U1, the 3 pin ground connection of amplifier IC2, the other end of resistance R10 connects electric capacity C2, 1 pin of amplifier IC3 and 3 pins of chip IC 4, 2 pins of amplifier IC3 connect 3 pins of amplifier IC3 and ground connection, 4 pins of amplifier IC3 connect power supply U1, the 5 pin contact resistance R11 of amplifier IC3 and 1 pin of chip IC 4, the other end of the other end contact resistance C2 of resistance R11, 2 pins of chip IC 4 connect power supply U1, 4 pin ground connection of chip IC 4, 5 pins of chip IC 4 connect 2 pins of amplifier IC5, 6 pins of chip IC 4 connect 12 pins of amplifier IC5, resistance R12 and electric capacity C3, 4 pins of amplifier IC5 connect power supply U1, the 3 pin ground connection of amplifier IC5, 5 pins of amplifier IC5 connect 2 pins of amplifier IC6, resistance R12 and electric capacity C3, the 1 pin contact resistance R13 of amplifier IC6 and electric capacity C4, 4 pins of amplifier IC6 connect power supply U1, the 3 pin ground connection of amplifier IC6, the 5 pin contact resistance R14 of amplifier IC6, resistance R12 and electric capacity C3, the other end of resistance R14 connects electric capacity C5, the negative pole of diode T1 and output Temp-out, the positive pole of diode T1 connects the other end of electric capacity C5 and ground connection.

2. a kind of high-frequency and high-voltage power supply temperature sensing circuit according to claim 1, it is characterized in that, described amplifier IC2, IC3, IC5 and IC6 are LM358 type amplifier, and described amplifier IC1 is AD620 instrumentation amplifier, and described chip IC 4 is HCRN201 type photo-coupler.

3. a kind of high-frequency and high-voltage power supply temperature sensing circuit according to claim 1, is characterized in that, described power supply U1 is 12V direct current.

4. a kind of high-frequency and high-voltage power supply temperature sensing circuit according to claim 1, is characterized in that, described resistance R5 is PT100 type thermistor, and the resistance of resistance R3 is 100 ohm.