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CN-224233660-U - HPLC medium voltage carrier high-power signal differential amplifying circuit

CN224233660UCN 224233660 UCN224233660 UCN 224233660UCN-224233660-U

Abstract

The utility model provides an HPLC medium-voltage carrier high-power signal differential amplification circuit, which relates to the technical field of amplification circuits and comprises a coupling transformer, a bridge type sensor, an adjustment analysis module, an AD acquisition circuit and an MCU module which are sequentially connected, wherein a common-mode surge suppressor is connected in series between the coupling transformer and the bridge type sensor, the adjustment analysis module at least comprises a digital potentiometer and a differential amplification module, and a control end of the digital potentiometer is connected with the MCU module. The utility model realizes that a common mode surge suppressor is connected in series between a coupling transformer and a bridge type sensor, is formed by connecting a transient voltage suppression diode array and a common mode choke coil in parallel, realizes transient overvoltage active clamping of more than six kilovolts per microsecond, reduces the breakdown risk of a later-stage circuit, and solves the problem that a conventional amplifying circuit is damaged due to power line coupling surge.

Inventors

  • WANG WENDA
  • WU CHUNBAO

Assignees

  • 青岛海讯达智能科技有限公司

Dates

Publication Date
20260512
Application Date
20250611

Claims (10)

  1. 1. The HPLC medium-voltage carrier high-power signal differential amplification circuit is characterized by comprising a coupling transformer (1), a bridge type sensor (2), an adjustment analysis module (3), an AD acquisition circuit (4) and an MCU module (5) which are connected in sequence; A common mode surge suppressor (6) is connected in series between the coupling transformer (1) and the bridge type sensor (2); The adjustment analysis module (3) at least comprises a digital potentiometer (31) and a differential amplification module (32), and the control end of the digital potentiometer (31) is connected with the MCU module (5).
  2. 2. The HPLC medium-voltage carrier high-power signal differential amplification circuit according to claim 1, wherein the common mode surge suppressor (6) is formed by connecting a transient voltage suppression diode array with a common mode choke in parallel.
  3. 3. The HPLC medium voltage carrier high power signal differential amplifying circuit of claim 2, wherein the clamping voltage of the transient voltage suppressing diode array is less than or equal to plus or minus fifteen volts, and the response time of the clamping voltage of the transient voltage suppressing diode array is less than or equal to one nanosecond.
  4. 4. The HPLC medium voltage carrier high power signal differential amplifier circuit of claim 2, wherein the common mode choke has an impedance of one kiloohm or more at a frequency of five hundred kilohertz and a saturation current of five hundred kilohertz or more.
  5. 5. The HPLC medium voltage carrier high power signal differential amplification circuit of claim 1, wherein the differential amplification module (32) adopts a high voltage slew rate instrumentation amplifier, and the slew rate of the high voltage slew rate instrumentation amplifier is greater than or equal to twenty volts per microsecond.
  6. 6. The HPLC medium voltage carrier high power signal differential amplifying circuit of claim 1, wherein the gain adjustment range of the digital potentiometer (31) is twenty dB to sixty dB, and the bandwidth of the digital potentiometer (31) is more than or equal to one MHz.
  7. 7. The HPLC medium-voltage carrier high-power signal differential amplification circuit of claim 1, wherein the adjustment analysis module (3) further comprises a band-pass filter unit (33), and the passband frequency of the band-pass filter unit (33) is three kilohertz to five hundred kilohertz.
  8. 8. The high-power signal differential amplification circuit of HPLC medium voltage carrier as set forth in claim 7, wherein the stopband attenuation of the band-pass filter unit (33) is greater than forty dB per decade.
  9. 9. The HPLC medium-voltage carrier high-power signal differential amplification circuit according to claim 1, wherein the MCU module (5) is connected with a digital potentiometer (31) through an isolated SPI interface and performs a dynamic gain calibration procedure.
  10. 10. The HPLC medium-voltage carrier high-power signal differential amplification circuit of claim 9, wherein the dynamic gain calibration procedure comprises monitoring the signal-to-noise value of the output signal of the AD acquisition circuit (4) in real time.

Description

HPLC medium voltage carrier high-power signal differential amplifying circuit Technical Field The utility model relates to the technical field of amplifying circuits, in particular to an HPLC medium-voltage carrier high-power signal differential amplifying circuit. Background In a high-speed power line carrier system, high-power signals on a medium-voltage line are required to be transmitted through a differential amplification circuit, common-mode noise is suppressed by the differential circuit in a complex medium-voltage power environment, only the differential signals are amplified, weak differential signals are effectively extracted through differential amplification, common-mode interference is suppressed, and the requirements of an HPLC system, namely the high-speed power line carrier system on high precision and low error rate are met. The utility model patent with the bulletin number of CN208689397U discloses a signal differential amplifying circuit which comprises a bridge type sensor, an adjusting and analyzing module, an AD acquisition circuit and an MCU module, wherein an original signal is converted into two paths of in-phase and opposite-phase input end voltage signals containing noise through the corresponding double-arm bridge type sensor, the voltage signals are sent to the adjusting and analyzing module, the signals are sent to the AD acquisition circuit after being processed by the adjusting and analyzing module, the AD acquisition circuit sends the signals to the MCU module, and the real signal differential amplifying circuit is accurate in control, safe, high in energy and stable in operation. In the above disclosure, the typical CMRR 100dB@1kHz is relied upon for AD623 suppression of common mode noise alone. In industrial sites such as motor interference or long-wire transmission, common-mode noise easily exceeds the chip suppression range, and the lightning and switch surge (> 6kV/μs) of power line coupling far exceeds the common-mode suppression capability of conventional instrument amplifiers such as AD623, resulting in signal distortion. Disclosure of utility model The utility model aims to solve the defects in the prior art, and provides an HPLC medium-voltage carrier high-power signal differential amplification circuit. The high-power signal differential amplification circuit for the HPLC medium-voltage carrier wave comprises a coupling transformer, a bridge type sensor, an adjustment analysis module, an AD acquisition circuit and an MCU module which are sequentially connected, wherein a common-mode surge suppressor is connected in series between the coupling transformer and the bridge type sensor, the adjustment analysis module at least comprises a digital potentiometer and a differential amplification module, and the control end of the digital potentiometer is connected with the MCU module. Preferably, the common mode surge suppressor is formed by connecting a transient voltage suppression diode array in parallel with a common mode choke. Preferably, the clamping voltage of the transient voltage suppression diode array is less than or equal to plus or minus fifteen volts, and the response time of the clamping voltage of the transient voltage suppression diode array is less than or equal to one nanosecond. Preferably, the impedance of the common mode choke coil at the frequency of five hundred kilohertz is equal to or more than one kiloohm, and the saturation current of the common mode choke coil at the frequency of five hundred kilohertz is equal to or more than five amperes. Preferably, the differential amplification module adopts a high-voltage slew rate instrumentation amplifier, and the slew rate of the high-voltage slew rate instrumentation amplifier is more than or equal to twenty volts per microsecond. Preferably, the gain adjustment range of the digital potentiometer is twenty db to sixty db, and the bandwidth of the digital potentiometer is greater than or equal to one megahertz. Preferably, the adjustment analysis module further comprises a band-pass filter unit, and the passband frequency of the band-pass filter unit is between three kilohertz and five hundred kilohertz. Preferably, the stop band attenuation is greater than forty db per decade. Preferably, the MCU module is connected with the digital potentiometer through an isolated SPI interface and executes a dynamic gain calibration program. Preferably, the dynamic gain calibration procedure includes monitoring the signal-to-noise value of the output signal of the AD acquisition circuit in real time. The beneficial effects are that: 1. The utility model realizes that a common mode surge suppressor is connected in series between a coupling transformer and a bridge type sensor, is formed by connecting a transient voltage suppression diode array and a common mode choke coil in parallel, realizes transient overvoltage active clamping of more than six kilovolts per microsecond, reduces the breakdown risk of a later-st