Alternating current impedance processing circuit, signal acquisition method and device, fuel cell voltage patrol instrument and medium

Abstract

The embodiment of the present application discloses an alternating current impedance processing circuit, a signal collection method and device based on the alternating current impedance processing circuit, a fuel cell voltage inspection instrument and a medium, wherein the alternating current impedance processing circuit comprises: at least two frequency selection modules in series, wherein the input end of the first frequency selection module is used as the input end of the alternating current impedance processing circuit, and is used for connecting an excitation signal; the output end of the alternating current impedance processing circuit is connected with an external control circuit through a gating switch; the external control circuit is used for selecting a corresponding target frequency band according to the frequency of the excitation signal, and controlling the gating switch to be opened for signal collection; wherein each frequency selection module comprises: a low-pass filter unit, a high-pass filter unit connected with the low-pass filter unit, and a signal amplification unit connected with the high-pass filter unit. By adopting the above technical scheme, the frequency range processed by the circuit is wider, and the gain of the circuit does not need to be fixed-point calibrated in the full-range frequency band.

Claims

1. An AC impedance processing circuit, characterized in that, include: At least two frequency selection modules are connected in series, so that the excitation signal is processed sequentially by each frequency selection module before being output. The input terminal of the first frequency selection module serves as the input terminal of an AC impedance processing circuit, used to receive the excitation signal. The output terminal of the AC impedance processing circuit is connected to an external control circuit via a gating switch. The external control circuit is used to select the corresponding target frequency band based on the frequency of the excitation signal and control the gating switch to open for signal acquisition. Each frequency selection module includes: A low-pass filter unit is used to perform low-pass filtering on the incoming AC signal. The AC signal connected to the low-pass filter unit of the first frequency selection module is the excitation signal. The AC signals connected to the filter units of other frequency selection modules besides the first frequency selection module are the AC signals output by the frequency selection modules connected to their input terminals. A high-pass filter unit, the input of which is connected to the output of the low-pass filter unit, is used to perform high-pass filtering on the output signal of the low-pass filter unit. The signal amplification unit includes a first resistor, a second resistor, an operational amplifier, and a feedback resistor. The non-inverting input of the operational amplifier is connected to the output of the high-pass filter unit. The inverting input of the operational amplifier is grounded through the first resistor and connected to the output of the operational amplifier through the second resistor. The output of the operational amplifier serves as the output of the signal amplification unit and is connected to the output of the low-pass filter unit through the feedback resistor. By setting the values ​​of the first resistor, the second resistor, and the feedback resistor, the gain of the signal amplification unit remains constant at all frequency points in different frequency bands.

2. The alternating current impedance processing circuit of claim 1, wherein, The AC impedance processing circuit includes two frequency selection modules, wherein, The first low-pass filter unit in the first frequency selection module includes: a third resistor and a first capacitor; the first high-pass filter unit in the first frequency selection module includes: a fourth resistor and a second capacitor, wherein, The first end of the third resistor is used to connect to the excitation signal, and the second end of the third resistor serves as the signal output terminal of the first low-pass filter unit and is grounded through the first capacitor. The first terminal of the second capacitor is connected to the second terminal of the third resistor, and the second terminal of the second capacitor is grounded through the fourth resistor.

3. The AC impedance processing circuit according to claim 2, characterized in that, The output terminal of the second frequency selection module is the output terminal of the AC impedance processing circuit, wherein... The second low-pass filter unit in the second frequency selection module includes a fifth resistor and a third capacitor; the second high-pass filter unit in the second frequency selection module includes a sixth resistor and a fourth capacitor, wherein, The first end of the fifth resistor is connected to the output end of the signal amplification unit in the first frequency selection module, and the second end of the fifth resistor serves as the signal output end of the second low-pass filter unit and is grounded through the third capacitor. The first terminal of the fourth capacitor is connected to the second terminal of the fifth resistor, and the second terminal of the fourth capacitor is grounded through the sixth resistor; The output terminal of the signal amplification unit in the second frequency selection module is connected to the gating switch.

4. The AC impedance processing circuit according to claim 1, characterized in that, The AC impedance processing circuit also includes an AC signal biasing module. The input terminal of the AC signal biasing module is connected to the output terminal of the external control circuit, and is used to control the AC signal output by the AC impedance processing circuit to be greater than 0V.

5. The AC impedance processing circuit according to claim 1, characterized in that, The target frequency band is any frequency band within the range of 1~10000HZ.

6. A signal acquisition method based on the AC impedance processing circuit as described in any one of claims 1 to 5, characterized in that, include: Receive instructions sent by a host computer, wherein the instructions include an excitation signal with a determined frequency and its corresponding frequency information; The corresponding target selection switch is turned on according to the frequency information of the excitation signal, so as to control the start of the AC impedance processing circuit connected to the target selection switch; The AC signal output from the AC impedance processing circuit is received, and the AC signal is sent to the AC signal bias module for bias processing so that the AC signal is greater than 0V. The AC signal biasing module controls the biased AC signal to be sent to the microcontroller unit (MCU) or analog-to-digital converter (ADC) chip for signal acquisition.

7. The method according to claim 6, characterized in that, The target frequency band is any frequency band within the range of 1~10000HZ.

8. A signal acquisition device based on the AC impedance processing circuit as described in any one of claims 1-5, characterized in that, include: The host computer instruction receiving module is configured to receive instructions sent by the host computer, wherein the instructions include an excitation signal with a determined frequency and its corresponding frequency information; The target frequency band selection module is configured to control the corresponding target gating switch to open according to the frequency information of the excitation signal, so as to control the AC impedance processing circuit connected to the target gating switch to start. The bias module is configured to receive the AC signal output by the AC impedance processing circuit and send the AC signal to the bias module for bias processing so that the AC signal is greater than 0V. The signal acquisition unit is configured to send the biased signal to the microcontroller unit (MCU) or analog-to-digital converter (ADC) chip for signal acquisition.

9. A fuel cell voltage monitoring device, characterized in that, include: The AC impedance processing circuit and control circuit as described in any one of claims 1 to 5, wherein the control circuit comprises: One or more processors; Storage device for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the signal acquisition method based on AC impedance processing circuit as described in claim 6 or 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the signal acquisition method based on the AC impedance processing circuit as described in claim 6 or 7.

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