High temperature resistant proportional valve control board

Abstract

The utility model discloses a kind of high-temperature-resistant proportional valve control panel, it is related to proportional valve control technology, including circuit board and board-mounted power supply conversion unit, CPU circuit, analog signal conversion circuit, I / O unit, proportional valve drive and other function circuits;Power supply conversion unit is equipped with input filter, rectification, DC-DC conversion and linear voltage stabilizing module.Module.The main power supply uses electrolysis, solid, tantalum capacitor parallel collocation-40~150 ℃ ceramic filter capacitor, board-mounted resistance is all precision 1 ‰, temperature-resistant-40~155 ℃ high-temperature resistance.The utility model selects type and multistage voltage stabilizing filter circuit by high-temperature-resistant component, improves the component deterioration of traditional control panel under high temperature, whole machine failure problem, can be long-term stable work in 150 ℃ or more high-temperature environment, adapts metallurgy, chemical industry, distillation and other high-temperature industrial scene.

Claims

1. A high-temperature resistant proportional valve control board, characterized in that, include: The circuit board and the power conversion unit, CPU circuit, program download circuit, proportional valve forward / reverse unit, I / O input unit, oscillation circuit, reset circuit, 0-3.3V to 0-20mA output circuit, 0-5V potentiometer input / position circuit, 4-20mA to 0-3.3V input circuit and I / O output unit mounted on the circuit board; The power conversion unit includes an input module, a rectification and filtering module, a conversion circuit module, and a power regulation unit; The input module includes a filter network consisting of a fuse, a varistor, an inductor, and a capacitor, and the filter network is electrically connected to a transformer; The rectifier and filter module includes a rectifier bridge, an electrolytic capacitor, and a power conversion chip. The rectifier bridge is electrically connected to the transformer, the electrolytic capacitor is electrically connected to the rectifier bridge, and the power conversion chip is electrically connected to the electrolytic capacitor. The conversion circuit module includes a DC-DC conversion circuit formed by an inductor, a Schottky diode, and a capacitor that are electrically connected to the power conversion chip. The power supply regulator unit is used to stabilize voltage and reduce ripple through a linear voltage regulator chip and external capacitors and resistors, so as to provide accurate and stable DC power supply to the load and protect the load. The main power supply filter uses electrolytic capacitors, solid capacitors, and tantalum capacitors connected in parallel, in conjunction with ceramic filter capacitors with an operating temperature range of -40℃ to 150℃. All resistors on the control board are 1‰ precision resistors with a temperature range of -40℃ to 155℃.

2. The high-temperature resistant proportional valve control board according to claim 1, characterized in that: The 4-20mA input to 0-3.3V converter uses a high-precision, low-noise OPA2188 operational amplifier chip and an HCNR201 opto-isolation chip to achieve accurate signal conversion and interference blocking. In the 0-3.3V to 0-20mA output circuit, an OPA2192 operational amplifier chip is used in conjunction with a totem-pole transistor for amplification, driving the field-effect transistor output, and opto-isolation is achieved through an HCNR201 opto-isolator; The 0-5V potentiometer input / position circuit uses the OPA2188 operational amplifier chip and the HCNR201 opto-isolation chip.

3. A high-temperature resistant proportional valve control board according to claim 2, characterized in that: The CPU circuit includes an STM32F103RET7 microcontroller and a power supply circuit, a reset circuit, and a clock circuit used in conjunction with the STM32F103RET7 microcontroller; high-temperature resistant resistors and ceramic filter capacitors are used in the power supply circuit, reset circuit, and clock circuit.

4. The high-temperature resistant proportional valve control board according to claim 3, characterized in that: The program download circuit includes a download interface, a BOOT startup configuration circuit, and a RUN control circuit.

5. A high-temperature resistant proportional valve control board according to claim 4, characterized in that: The proportional valve forward and reverse rotation unit is isolated by resistors and optocouplers, drives a bidirectional thyristor, and, in conjunction with resistors, inductors and JP5 interface, realizes the forward and reverse rotation control of the proportional valve.

6. A high-temperature resistant proportional valve control board according to claim 5, characterized in that: The I / O input unit includes a signal input terminal, which is filtered by resistors and capacitors and then connected to an optocoupler. The output of the optocoupler is connected to the CPU.

7. A high-temperature resistant proportional valve control board according to claim 6, characterized in that: The 0-5V potentiometer input / position circuit uses an OPA2188 operational amplifier chip, an HCNR201 isolation chip, high-temperature resistant resistors, and capacitors to process the 0-5V potentiometer input signal and accurately acquire position information.

8. A high-temperature resistant proportional valve control board according to claim 7, characterized in that: In the 4-20mA to 0-3.3V input circuit, 4-20mA output circuit, and 0-5V to 0-3.3V circuit, the operational amplifier chip and the isolation chip work together to block external interference signals.

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