A parameter detection circuit and method

Abstract

A parameter detection circuit and method achieve the detection of the original reference voltage source by adding a reference voltage source, so as to determine whether there is a fault in the original reference voltage source and improve the detection accuracy of the parameter detection circuit.

Description

Technical Field

[0001] This application belongs to the technical field of electronic circuits, and particularly relates to a parameter detection circuit and method. Background Art

[0002] Currently, in the field of electric energy metering, a sampling network is usually used to sample the measured voltage and current signals, and then input them into an analog-to-digital converter to convert them into digital signals. Finally, a signal processor is used to process the digital signals to obtain the measurement values. However, when the parameters of the components in the sampling network change due to faults, sampling errors will occur, and ultimately measurement errors will be generated. For this situation, the measurement system needs to be able to detect it and perform corresponding processing.

[0003] A detection signal generation circuit is usually used to detect the sampling network, which can determine whether the parameters of the sampling network have changed, and then locate the fault source. Specifically, by introducing an additional detection signal generated based on a reference voltage source into the nodes of the sampling network, and analyzing the measurement results of the detection signal by the signal processor, it is determined whether the parameters of the sampling network have changed, and then the fault source is located.

[0004] In the traditional technology, the reference voltage source provides the reference voltage for both the detection signal generation circuit and the analog-to-digital converter. To ensure the accuracy of the system, it is usually required that the reference voltage has a fast response and low noise. Specifically, the reference voltage source needs to be connected to an external pin, and a capacitor is added to the external pin. Since the reference voltage source is connected to the external pin, it is more likely to be damaged during chip operation, resulting in a change in the voltage value of the reference voltage source. However, when the voltage value of the reference voltage source changes, the detection signal generated by the detection signal generation circuit will change proportionally, and the digital signal converted by the analog-to-digital converter will change inversely, ultimately making the detection value remain unchanged and the same as the reference value.

[0005] It can be seen that the traditional measurement system cannot detect the fault of the reference voltage source, and the change in the reference voltage value provided by the reference voltage source cannot be recognized. Summary of the Invention

[0006] The purpose of this application is to provide a parameter detection circuit and method with a reference detection function, aiming to solve the problem that the traditional parameter detection circuit cannot detect the fault of the reference voltage source.

[0007] A parameter detection circuit includes:

[0008] A first reference voltage source for providing a first reference voltage;

[0009] A second reference voltage source for providing a second reference voltage;

[0010] Detection signal generation circuit;

[0011] A selection switch, connected to the first reference voltage source, the second reference voltage source and the detection signal generation circuit, the selection switch is configured to selectively connect the detection signal generation circuit to one of the first reference voltage source and the second reference voltage source to provide the detection signal generation circuit with the first reference voltage or the second reference voltage; the detection signal generation circuit is configured to generate a first detection signal and a second detection signal according to the first reference voltage and the second reference voltage respectively;

[0012] A sampling network, configured to be connected to a measurement signal and the detection signal generation circuit, and configured to access the first detection signal and the second detection signal, and output a first detection sampling signal and a second detection sampling signal respectively;

[0013] An analog-to-digital converter, connected to the sampling network and the first reference voltage source, and configured to convert the first detection sampling signal and the second detection sampling signal into corresponding digital signals under the condition that the first reference voltage source provides the first reference voltage;

[0014] A signal processor, connected to the analog-to-digital converter, and configured to determine whether the first reference voltage source has a fault according to the first detection sampling signal and the second detection sampling signal converted into digital signals.

[0015] In one embodiment, the signal processor is specifically configured to determine whether the first reference voltage source has a fault according to the change of the calibration value and the detection value of the first detection sampling signal converted into a digital signal and the change of the calibration value and the detection value of the second detection sampling signal converted into a digital signal.

[0016] In one embodiment, the signal processor is further configured to determine whether the sampling network has a fault according to the change of the calibration value and the detection value of the first detection sampling signal converted into a digital signal.

[0017] In one embodiment, the sampling network accesses the measurement signal and also outputs a measurement sampling signal, the analog-to-digital converter converts the measurement sampling signal into a digital signal, and the signal processor is further configured to perform power measurement and calibration according to the first detection sampling signal and / or the second detection sampling signal converted into a digital signal, and the measurement sampling signal.

[0018] In one embodiment, the frequencies of the first detection signal and the second detection signal are greater than the frequency of the measurement signal, and are non-integer multiples of the measurement signal.

[0019] In one embodiment, the second reference voltage source and the signal processor are on-chip circuits of an integrated circuit, and at least some of the devices of the first reference voltage source, the detection signal generation circuit, and the sampling network are off-chip circuits of the integrated circuit.

[0020] In addition, a parameter detection method is provided, including:

[0021] Generating a first detection signal based on a first reference voltage generated by a first reference voltage source and loading it onto a sampling network to generate a first detection sampling signal;

[0022] Generating a second detection signal based on a second reference voltage generated by a second reference voltage source and loading it onto the sampling network to generate a second detection sampling signal;

[0023] Based on the first reference voltage, converting the first detection sampling signal and the second detection sampling signal into digital signals respectively;

[0024] Determining whether the first reference voltage source has a fault according to the first detection sampling signal and the second detection sampling signal converted into digital signals.

[0025] In one embodiment, the determining whether the first reference voltage source has a fault according to the first detection sampling signal and the second detection sampling signal converted into digital signals includes:

[0026] Determining whether the first reference voltage source has a fault according to the change in the calibration value and the detection value of the first detection sampling signal converted into a digital signal and the change in the calibration value and the detection value of the second detection sampling signal converted into a digital signal.

[0027] In one embodiment, it further includes determining whether the sampling network has a fault according to the change in the calibration value and the detection value of the first detection sampling signal converted into a digital signal.

[0028] In one embodiment, it further includes:

[0029] Loading a measurement signal onto the sampling network to generate a measurement sampling signal;

[0030] Based on the first reference voltage, converting the measurement sampling signal into a digital signal;

[0031] Performing power measurement and its calibration according to the first detection sampling signal and / or the second detection sampling signal converted into digital signals, and the measurement sampling signal.

[0032] The above-mentioned parameter detection circuit and method detect the original reference voltage source by adding a reference voltage source, so as to determine whether there is a fault in the original reference voltage source and improve the detection accuracy of the parameter detection circuit. Description of the Drawings

[0033] Figure 1 Schematic diagram of the parameter detection circuit provided by an embodiment of the present application;

[0034] Figure 2 Flow chart of the parameter detection method provided by an embodiment of the present application. Detailed Embodiments

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0036] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0037] Please refer to Figure 1 , the parameter detection circuit of the embodiment of the present application includes: a first reference voltage source 10 for providing a first reference voltage, a second reference voltage source 20 for providing a second reference voltage, a detection signal generation circuit 30, a selection switch 40, a sampling network 50, an analog-to-digital converter 60, and a signal processor 70.

[0038] The selection switch 40 is connected to the first reference voltage source 10, the second reference voltage source 20, and the detection signal generation circuit 30. The selection switch 40 is configured to selectively connect either the first reference voltage source 10 or the second reference voltage source 20 to the detection signal generation circuit 30 to provide the first reference voltage or the second reference voltage to the detection signal generation circuit 30; the detection signal generation circuit 30 is configured to generate a first detection signal and a second detection signal according to the first reference voltage and the second reference voltage respectively.

[0039] The sampling network 50 is used to connect to the measurement signal and the detection signal generation circuit 30, and is configured to access the first detection signal and the second detection signal, and respectively output a first detection sampling signal and a second detection sampling signal. The analog-to-digital converter 60 is connected to the sampling network 50 and the first reference voltage source 10, and is used to convert the first detection sampling signal and the second detection sampling signal into corresponding digital signals under the first reference voltage provided by the first reference voltage source 10. The signal processor 70 is connected to the analog-to-digital converter 60, and is used to determine whether there is a fault in the first reference voltage source 10 according to the first detection sampling signal and the second detection sampling signal converted into digital signals.

[0040] In this embodiment, the analog-to-digital converter 60 is provided with a reference voltage by the first reference voltage source 10, and the first reference voltage source 10 needs to be connected to an external pin; the detection signal generation circuit 30 can select to be provided with a reference voltage by the first reference voltage source 10 or the second reference voltage source 20 through a selection switch. The second reference voltage source 20 is only an internal circuit of the integrated circuit and is not connected to an external pin. Since the second reference voltage source 20 is only an internal circuit of the integrated circuit, it naturally has high reliability.

[0041] The working process of this application is divided into two stages: the calibration stage and the usage stage.

[0042] Among them, the calibration stage means that: when initially leaving the factory, the sampling network 50 will be calibrated through the detection signal. The calibration stage is divided into two times: when selecting the first reference voltage source 10 to provide a reference voltage for the detection signal generation circuit 30, the value of the first detection sampling signal is calibrated to the calibration value V EDTA0 . When selecting the second reference voltage source 20 as the reference voltage for the detection signal generation circuit 30, the value of the second detection sampling signal is calibrated to the calibration value V EDTB0 ; the usage stage means that: during the usage process, when selecting the first reference voltage source 10 to provide a reference voltage for the detection signal generation circuit 30, the detected value V of the first detection sampling signal EDTAN is compared with the calibration value V EDTA0 . Regularly, when selecting the second reference voltage source 20 as the reference voltage for the detection signal generation circuit 30, the detected value V of the second detection sampling signal EDTBN is compared with the calibration value V EDTB0 .

[0043] Therefore, in one of the embodiments, the signal processor 70 is specifically used to determine according to the calibration value V of the first detection sampling signal converted into a digital signal EDTA0 and the change of the detected value V EDTAN and the calibration value V of the second detection sampling signal converted into a digital signal EDTB0 and the detected value V EDTBNThe change determines whether there is a fault in the first reference voltage source 10. Specifically, if the detected value V of the first detected sampling signal of the digital signal EDTAN is the same as the calibrated value V EDTA0 , but the detected value V of the second detected sampling signal of the digital signal EDTBN is different from the calibrated value V EDTB0 , it indicates that the first reference voltage source 10 has changed, that is, there is an abnormality and a fault may occur.

[0044] The detection signal generation circuit 30 can be a voltage / current generation circuit.

[0045] In addition, in one embodiment, the signal processor 70 is further configured to determine whether the sampling network 50 is abnormal according to the change between the calibrated value and the detected value of the first detected sampling signal converted into a digital signal. Specifically, if the detected value V of the first detected sampling signal converted into a digital signal EDTAN is different from the calibrated value V EDTA0 , it indicates that the parameters of the sampling network 50 have changed.

[0046] Furthermore, the sampling network 50 accesses the measurement signal and also outputs a measurement sampling signal. The analog-to-digital converter 60 converts the measurement sampling signal into a digital signal. The signal processor is further configured to perform power measurement and its calibration according to the first detected sampling signal and / or the second detected sampling signal converted into a digital signal, and the measurement sampling signal.

[0047] Furthermore, the signal processor 70 processes the first detected sampling signal and the second detected sampling signal converted into digital signals, respectively obtains the amplitude value and phase value of the first detected sampling signal and the amplitude value and phase value of the second detected sampling signal, and determines whether the circuit parameters of the sampling network 50 are abnormal according to at least one of the amplitude value change of the first detected sampling signal, the amplitude value change of the second detected sampling signal, the phase change of the first detected sampling signal, and the phase change of the second detected sampling signal. And calibrate the measurement sampling signal according to the abnormal situation of the circuit parameters of the sampling network 50, and then perform power measurement with the accurate measurement sampling signal.

[0048] In one embodiment, the frequencies of the first detection signal and the second detection signal are greater than the frequency of the measurement sampling signal and are non-integer multiples of the measurement signal.

[0049] In one embodiment, the second reference voltage source 20 and the signal processor 70 are on-chip circuits of the integrated circuit, and at least some of the devices of the first reference voltage source 10, the detection signal generation circuit 30, and the sampling network 50 are off-chip circuits of the integrated circuit. Among them, the external capacitor in the first reference voltage source 10 and the pin connecting the capacitor are off-chip circuits of the integrated circuit.

[0050] In addition, please refer to Figure 2 , and a parameter detection method is also provided, including the following steps:

[0051] Step S110: Generate a first detection signal based on a first reference voltage generated by a first reference voltage source and load it onto a sampling network to generate a first detection sampling signal;

[0052] Step S120: Generate a second detection signal based on a second reference voltage generated by a second reference voltage source and load it onto the sampling network to generate a second detection sampling signal;

[0053] Step S130: Based on the first reference voltage, convert the first detection sampling signal and the second detection sampling signal into digital signals respectively;

[0054] Step S140: Determine whether the first reference voltage source has a fault according to the first detection sampling signal and the second detection sampling signal converted into digital signals.

[0055] In one embodiment, determining whether the first reference voltage source has a fault according to the first detection sampling signal and the second detection sampling signal converted into digital signals includes:

[0056] Determine whether the first reference voltage source has a fault according to the change of the calibration value and the detection value of the first detection sampling signal converted into a digital signal and the change of the calibration value and the detection value of the second detection sampling signal converted into a digital signal.

[0057] In one embodiment, it further includes determining whether the sampling network has a fault according to the change of the calibration value and the detection value of the first detection sampling signal converted into a digital signal.

[0058] In one embodiment, it further includes:

[0059] Load a measurement signal onto the sampling network to generate a measurement sampling signal;

[0060] Based on the first reference voltage, convert the measurement sampling signal into a digital signal;

[0061] Perform power measurement and calibration according to the first detection sampling signal and / or the second detection sampling signal converted into digital signals, and the measurement sampling signal.

[0062] The above parameter detection circuit and method improve the detection accuracy of the parameter detection circuit by adding a reference voltage source to detect the original reference voltage source to determine whether the original reference voltage source has a fault.

[0063] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included within the protection scope of the present application.

Claims

1. A parameter detection circuit, characterized in that, Comprising: A first reference voltage source for providing a first reference voltage; A second reference voltage source for providing a second reference voltage; A detection signal generation circuit; A selection switch connected to the first reference voltage source, the second reference voltage source and the detection signal generation circuit, the selection switch being configured to selectively connect either the first reference voltage source or the second reference voltage source to the detection signal generation circuit to provide the first reference voltage or the second reference voltage to the detection signal generation circuit; The detection signal generation circuit is configured to generate a first detection signal and a second detection signal according to the first reference voltage and the second reference voltage respectively; A sampling network for connecting to a measurement signal and the detection signal generation circuit, configured to access the first detection signal and the second detection signal and output a first detection sampling signal and a second detection sampling signal respectively; An analog-to-digital converter connected to the sampling network and the first reference voltage source, for converting the first detection sampling signal and the second detection sampling signal into corresponding digital signals under the condition that the first reference voltage source provides the first reference voltage; A signal processor connected to the analog-to-digital converter, for determining whether the first reference voltage source is abnormal according to the first detection sampling signal and the second detection sampling signal converted into digital signals; specifically, the signal processor is configured to determine whether the first reference voltage source is abnormal according to the change of the calibration value and the detection value of the first detection sampling signal converted into digital signals and the change of the calibration value and the detection value of the second detection sampling signal converted into digital signals; The signal processor is further configured to determine whether the sampling network is abnormal according to the change of the calibration value and the detection value of the first detection sampling signal converted into digital signals.

2. The parameter detection circuit according to claim 1, wherein The sampling network accesses the measurement signal and also outputs a measurement sampling signal, the analog-to-digital converter converts the measurement sampling signal into a digital signal, and the signal processor is further configured to perform power measurement and its calibration according to the first detection sampling signal and / or the second detection sampling signal converted into digital signals and the measurement sampling signal.

3. The parameter detection circuit according to claim 2, wherein, The frequencies of the first detection signal and the second detection signal are greater than the frequency of the measurement signal and are non-integer multiples of the measurement signal.

4. The parameter detection circuit according to claim 1, characterized in that, The second reference voltage source and the signal processor are on-chip circuits of an integrated circuit, and at least some of the devices of the first reference voltage source, the detection signal generation circuit and the sampling network are off-chip circuits of the integrated circuit.

5. A parameter detection method, characterized in that, Comprising: Generating a first detection signal based on the first reference voltage generated by the first reference voltage source and loading it onto the sampling network to generate a first detection sampling signal; Generating a second detection signal based on the second reference voltage generated by the second reference voltage source and loading it onto the sampling network to generate a second detection sampling signal; Converting the first detection sampling signal and the second detection sampling signal into digital signals respectively based on the first reference voltage; Determining whether the first reference voltage source is abnormal according to the first detection sampling signal and the second detection sampling signal converted into digital signals; Determining whether the first reference voltage source is abnormal based on the first detection sampling signal and the second detection sampling signal converted into digital signals includes: Determining whether the first reference voltage source is abnormal according to the changes in the calibrated value and the detected value of the first detection sampling signal converted into a digital signal and the changes in the calibrated value and the detected value of the second detection sampling signal converted into a digital signal.

6. The parameter detection method according to claim 5, wherein It further includes determining whether the sampling network is abnormal according to the changes in the calibrated value and the detected value of the first detection sampling signal converted into a digital signal.

7. The parameter detection method according to claim 5, characterized in that, It further includes: Loading a measurement signal on the sampling network to generate a measurement sampling signal; Converting the measurement sampling signal into a digital signal based on the first reference voltage; Performing power measurement and its calibration according to the first detection sampling signal and / or the second detection sampling signal converted into a digital signal, and the measurement sampling signal.

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