Compatible with GB / T7354 standard partial discharge detection composite impedance device and method

Abstract

The present invention discloses a composite impedance device and method for partial discharge detection that is compatible with the GB / T7354 standard. The present invention includes a standard impedance module, a broadband impedance module, a WIFI communication module, a control circuit module, and a power supply module, as well as a normally closed switch, a normally open switch, and a single-pole double-throw switch. The partial discharge detection host using the pulse current method has a standard detection mode and a broadband detection mode. The standard impedance module complies with the GB / T7354 standard, and the detection bandwidth is greater than or equal to 10kHz and less than or equal to 1MHz; the detection bandwidth of the broadband impedance module is greater than 1MHz and less than or equal to 80MHz. The control circuit module controls the opening and closing of each switch according to the command transmitted by the WIFI communication module to the partial discharge detection host, and selects to switch between the standard impedance module and the broadband impedance module. The present invention can match the partial discharge measurement of the detection host under the standard frequency band and the broadband, and control the switching in real time through remote WiFi, which is safer and more reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of partial discharge detection, and in particular to a partial discharge detection composite impedance device and method compatible with the GB / T7354 standard. Background Art

[0002] In the field of partial discharge detection technology, the pulse current method is the most effective and widely used PD detection method. Comprehensive standards have been established for this method both internationally and domestically. The current national standard is GB / T 7354-2018, "High Voltage Test Technology for Partial Discharge Measurement." The detection impedance is a key sensing element in pulse current PD measurement. During the PD test, the detection impedance converts the high-frequency pulse current signal in the test circuit into a pulse voltage signal. The pulse current PD detector calculates and analyzes the signal and ultimately presents the data to the user interface. In pulse current PD detection, the PD signal and interference signal frequency range primarily ranges from 10kHz to 80MHz. Signals below 1MHz have a narrow bandwidth and contain less information. However, the frequency band above 1MHz and below 80MHz contains a significant amount of PD signals, allowing for more accurate reflection of the signal's microscopic waveform and sufficient information. The current GB / T 7354 standard defines the upper limit frequency of the signal output by impedance coupling during pulse current detection as less than or equal to 1MHz. This means that signals with frequencies above 10kHz and below 80MHz, after standard impedance coupling and modulation, have an output frequency of less than 1MHz. This output signal makes it difficult to distinguish between partial discharge signals and interference signals, and cannot accurately restore the signal's pulse duration, amplitude, rise and fall times, bandwidth, phase, and other parameters. To achieve impedance coupling output of a broadband signal between 10kHz and 80MHz during pulse current partial discharge detection and effectively restore the signal's characteristic parameters, it is necessary to design a composite impedance device and method for partial discharge detection that is compatible with the GB / T 7354 standard. Summary of the Invention

[0003] One object of the present invention is to provide a composite impedance device for partial discharge detection that is compatible with the GB / T7354 standard.

[0004] The composite impedance device for partial discharge detection, compatible with the GB / T7354 standard, includes a standard impedance module, a broadband impedance module, a WiFi communication module, a control circuit module, and a power supply module, as well as a normally closed switch, a normally open switch, and a single-pole double-throw switch.

[0005] The standard impedance module complies with the GB / T7354 standard, has a detection bandwidth greater than or equal to 10kHz and less than or equal to 1MHz, and is used to cooperate with the partial discharge detection host to measure in standard mode.

[0006] The broadband impedance module has a detection bandwidth greater than 1 MHz and less than or equal to 80 MHz, and is used to cooperate with the partial discharge detection host to measure in broadband mode.

[0007] The PD detection host uses the pulse current method and has a standard detection mode and a broadband detection mode. The standard detection mode is a measurement mode in the PD detection host software that complies with the GB / T7354 standard, while the broadband mode is a measurement mode in the PD detection host software suitable for broadband PD detection.

[0008] The WIFI communication module is connected to the control circuit module to create a wireless access point, and the partial discharge detection host is connected to the WIFI communication module signal.

[0009] The control circuit module controls the opening and closing of the switch according to the command transmitted by the WIFI communication module to the partial discharge detection host, and selects to switch between the standard impedance module and the broadband impedance module.

[0010] The power supply module supplies power to the WIFI communication module and the control circuit module.

[0011] One end of the normally closed switch is connected to the signal input end, and the other end is connected to the standard impedance module, and is controlled to close by the control circuit module; one end of the normally open switch is connected to the signal input end, and the other end is connected to the broadband impedance module, and is controlled to close by the control circuit module; one end of the single-pole double-throw switch is connected to the signal output end, and the first contact in the other end is connected to the standard impedance module, and the second contact is connected to the broadband impedance module. The control circuit module controls the single-pole double-throw switch to switch between the first contact and the second contact. In the initialization state, the first contact of the single-pole double-throw switch is defaulted to be conductive.

[0012] Another object of the present invention is to provide a method for partial discharge detection using the partial discharge detection composite impedance device.

[0013] When conducting a pulse current method test, the partial discharge detection composite impedance device is connected to the test circuit, the power is turned on, the WIFI communication module creates a wireless WIFI access point, and the partial discharge detection host is connected to the wireless WIFI access point created by the WIFI communication module to maintain a communicative state; the initial state of the partial discharge detection composite impedance device is that the normally closed switch is closed, and the single-pole double-throw switch is connected to the first contact. At this time, the standard impedance module of the partial discharge detection composite impedance device is turned on, and the partial discharge detection host performs detection in the standard measurement mode.

[0014] Select the broadband measurement mode on the partial discharge detection host. The partial discharge detection host transmits instructions to the control circuit module through the WiFI communication module. The instructions are to first close the normally open switch, then open the normally closed switch, and then switch the single-pole double-throw switch to the second contact. At this time, the broadband impedance module of the partial discharge detection composite impedance device is turned on, and the partial discharge detection host performs detection in the broadband measurement mode.

[0015] Select the standard measurement mode on the partial discharge detection host. The partial discharge detection host transmits instructions to the control circuit module through the WiFI communication module. The instructions are to first close the normally closed switch, then open the normally open switch, and then switch the single-pole double-throw switch to the first contact. At this time, the partial discharge detection composite impedance device switches back to the standard impedance module conduction state, and the partial discharge detection host performs measurements in the standard measurement mode.

[0016] The present invention controls the opening and closing of a normally closed switch, a normally open switch, and a single-pole double-throw switch, so that when performing partial discharge pulse current detection, it further controls the selection of a standard impedance module or a broadband impedance module in a composite impedance device to be connected to a test circuit, and cooperates with a partial discharge detection host to complete measurement in standard mode or broadband mode.

[0017] The present invention provides a broadband partial discharge detection composite impedance device and method compatible with the GB / T7354 standard. The device and method can not only match a detection host for partial discharge measurements in accordance with the GB / T7354 standard, but can also match the detection host for partial discharge measurements over a wide frequency band. Furthermore, during on-site tests, remote WiFi can be used for real-time control switching, avoiding power outages and switching during the test, as well as potential safety hazards for test personnel working at height. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the internal component modules of the composite impedance;

[0019] Figure 2 Schematic diagram of achieving standard impedance and broadband impedance switching within a composite impedance. DETAILED DESCRIPTION

[0020] like Figure 1 and 2 As shown, the composite impedance device for partial discharge detection compatible with the GB / T7354 standard includes a standard impedance module 1, a broadband impedance module 2, a WIFI communication module 3, a control circuit module 4, a power supply module 5, a normally closed switch 6, a normally open switch 7, and a single-pole double-throw switch 8. Among them:

[0021] Standard impedance module 1 complies with GB / T7354, with a detection bandwidth greater than or equal to 10 kHz and less than or equal to 1 MHz. It is used in conjunction with a partial discharge detection host computer in standard measurement mode. Control module circuit 4 controls whether standard impedance module 1 is connected to the test circuit and is used in conjunction with the partial discharge detection host computer in standard measurement mode. One end of standard impedance module 1 is connected to a normally closed switch 6, and the other end is connected to contact a of a single-pole double-throw switch 8.

[0022] The broadband impedance module 2 has a detection bandwidth greater than 1 MHz and less than or equal to 80 MHz, and is used in conjunction with the PD detection host computer in broadband mode. Control module circuit 4 controls whether broadband impedance module 2 is connected to the test circuit and operates in broadband measurement mode. One end of broadband impedance module 2 is connected to a normally open switch 7, and the other end is connected to contact b of a single-pole double-throw switch 8.

[0023] The PD detection host uses the pulse current method and features both standard and broadband detection modes. Standard detection mode is a measurement mode within the PD detection host software that complies with the GB / T7354 standard, while broadband mode is a measurement mode suitable for broadband PD detection within the PD detection host software.

[0024] The WIFI communication module 3 is serially connected to the control circuit module 4 to create a wireless access point. The partial discharge detection host is signal-connected to the WIFI communication module 3. The WIFI communication module 3 can transmit instructions from the partial discharge detection host to the control circuit module 4.

[0025] The control circuit module 4 controls the opening and closing of the switch according to the command transmitted by the PD detection host by the WIFI communication module 3, and selects the standard impedance module or the broadband impedance module.

[0026] The power supply module 5 supplies power to the WIFI communication module 3 and the control circuit module 4 .

[0027] like Figure 2 As shown, one end of the normally closed switch 6 is connected to the signal input terminal and the other end is connected to the standard impedance module 1. The normally open switch 7 is connected to the signal input terminal and the other end is connected to the broadband impedance module. The normally open switch 7 is controlled by the control circuit module 4. One end of the single-pole double-throw switch 8 is connected to the signal output terminal. One contact a of the other end is connected to the standard impedance module 1, and the other contact b is connected to the broadband impedance module 2. The control circuit module 4 controls the single-pole double-throw switch 8 to switch between contact a and contact b. In the initial state, the default is that the single-pole double-throw switch contact a is on.

[0028] During a pulse current method test, the PD detection composite impedance device is connected to the test circuit, the power is turned on, and the WIFI communication module 3 establishes a wireless WIFI access point. The PD detection host connects to the wireless WIFI access point established by the WIFI communication module 3, maintaining a communication state. The PD detection composite impedance device is initially in the closed state with the normally closed switch 6 closed and the single-pole double-throw switch 8 connected to contact a. At this point, the standard impedance module 1 of the PD detection composite impedance device is turned on, and the PD detection host performs detection in standard measurement mode.

[0029] Select the broadband measurement mode on the partial discharge detection host. The partial discharge detection host transmits instructions to the control circuit module 4 through the WiFI communication module 3. The instructions are to first close the normally open switch 7, then open the normally closed switch 6, and then switch the single-pole double-throw switch 8 to contact b. At this time, the broadband impedance module 2 of the partial discharge detection composite impedance device is turned on, and the partial discharge detection host performs detection in the broadband measurement mode.

[0030] The standard measurement mode is selected on the partial discharge detection host. The partial discharge detection host transmits instructions to the control circuit module 4 through the WiFI communication module 3. The instructions are to first close the normally closed switch 6, then open the normally open switch 7, and then switch the single-pole double-throw switch 8 to contact a. At this time, the partial discharge detection composite impedance device switches back to the conductive state of the standard impedance module 1, and the partial discharge detection host performs measurements in the standard measurement mode.

Claims

1. Compatible with the GB / T7354 standard partial discharge detection method, using a partial discharge detection composite impedance device, it can match the detection host to measure partial discharge in accordance with the GB / T7354 standard, and can also match the detection host to measure partial discharge in a wide bandwidth; its characteristics are: The composite impedance device for partial discharge detection includes a standard impedance module, a broadband impedance module, a WiFi communication module, a control circuit module, and a power supply module, as well as a normally closed switch, a normally open switch, and a single-pole double-throw switch. During the pulse current method partial discharge detection process, the detection impedance is coupled to output a broadband signal of 10kHz to 80MHz, truly restoring the characteristic quantity of the signal. The standard impedance module complies with the GB / T7354 standard, has a detection bandwidth greater than or equal to 10kHz and less than or equal to 1MHz, and is used to cooperate with the partial discharge detection host to measure in standard mode; The broadband impedance module has a detection bandwidth greater than 1 MHz and less than or equal to 80 MHz, and is used to cooperate with the partial discharge detection host to measure in broadband mode; The partial discharge detection host adopts the pulse current method and has a standard detection mode and a broadband detection mode. The standard detection mode is a measurement mode in the partial discharge detection host software that complies with the GB / T7354 standard, and the broadband mode is a measurement mode in the partial discharge detection host software that is suitable for broadband partial discharge detection. The WIFI communication module is connected to the control circuit module to create a wireless access point, and the partial discharge detection host is connected to the WIFI communication module signal; The control circuit module controls the opening and closing of the switch according to the command transmitted by the PD detection host by the WIFI communication module, and selects the standard impedance module or the broadband impedance module; The power supply module supplies power to the WIFI communication module and the control circuit module; One end of the normally closed switch is connected to the signal input end, and the other end is connected to the standard impedance module, and is controlled to close by the control circuit module; one end of the normally open switch is connected to the signal input end, and the other end is connected to the broadband impedance module, and is controlled to close by the control circuit module; one end of the single-pole double-throw switch is connected to the signal output end, and the first contact at the other end is connected to the standard impedance module, and the second contact is connected to the broadband impedance module. The control circuit module controls the single-pole double-throw switch to switch between the first contact and the second contact. In the initialization state, the first contact of the single-pole double-throw switch is defaulted to be conductive. When conducting a pulse current method test, the composite partial discharge detection device is connected to the test circuit, the power is turned on, the WIFI communication module creates a wireless WIFI access point, and the partial discharge detection host connects to the wireless WIFI access point created by the WIFI communication module to maintain a communicative state; the initial state of the composite partial discharge detection device is that the normally closed switch is closed, the single-pole double-throw switch is connected to the first contact, the standard impedance module of the composite partial discharge detection device is turned on, and the partial discharge detection host performs detection in the standard measurement mode; The broadband measurement mode is selected on the PD detection host. The PD detection host transmits instructions to the control circuit module via the WiFI communication module. The instructions are to first close the normally open switch, then open the normally closed switch, and then switch the single-pole double-throw switch to the second contact. At this time, the broadband impedance module of the composite PD detection device is turned on, and the PD detection host performs detection in the broadband measurement mode. Select the standard measurement mode on the partial discharge detection host. The partial discharge detection host transmits instructions to the control circuit module through the WiFI communication module. The instructions are to first close the normally closed switch, then open the normally open switch, and then switch the single-pole double-throw switch to the first contact. At this time, the composite partial discharge detection device switches back to the standard impedance module conduction state, and the partial discharge detection host performs measurements in the standard measurement mode.

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