CN103245837B - Insulation resistance measuring method and device supporting output voltage of any point - Google Patents

Abstract

The present invention discloses an insulation resistance measurement method supporting output voltage at any point, characterized in that it includes the following steps: (1) a main control chip is set in the measurement circuit, and functional software is embedded in the main control chip; (2) a reference generation module is set to output a high-voltage reference signal; (3) a high-voltage inverter generation module and a precise negative feedback circuit module are set to stably output a high-voltage measurement signal; (4) a high-voltage attenuation circuit module and a loop current sampling module are set to output an insulation resistance measurement voltage signal and an insulation resistance measurement current signal; (5) a low-pass filter is set to perform filtering processing; (6) a precise analog-to-digital converter circuit module is set to perform digital conversion of the signal; (7) a display module is set to output and display the measurement result. The present invention also discloses a measurement device for implementing the above insulation resistance measurement method supporting output voltage at any point.

Description

A method and device for measuring insulation resistance supporting output voltage at any point

technical field

The invention relates to the field of electronic measurement, in particular to an insulation resistance measurement method supporting output voltage at any point, and a measurement device for implementing the method.

Background technique

Insulation resistance refers to the resistance value that occurs when a voltage is applied to the insulating part of the connector, and then a leakage current occurs in or on the surface of the insulating part. It is mainly affected by factors such as insulating materials, temperature, humidity, and fouling. The insulation resistance value provided on the connector sample is generally the target value under standard atmospheric conditions. In some circumstances, the insulation resistance value will drop to an unreasonable degree. In addition, pay attention to the test voltage value of the insulation resistance. According to the voltage applied to the insulator by the insulation resistance, different voltages are applied to the leakage current, which has unnecessary effects.

The traditional 5 output voltage insulation resistance measurement method is to use 5 rotary disc switches to switch the resistance mechanically, and then amplify through the high voltage generator to realize the output of 5 output insulation resistance measurement voltages. The mechanical structure principle of the rotary switch is combined with the circuit principle and the circuit board PCB to realize the measured voltage output; that is: when the rotary switch points to a voltage point in the five voltage (50V/100V/250V/500V/1000V) ranges, the relative Inside the structure, the circuit board circuit corresponding to the function is connected, so as to realize the function of measuring voltage output. Traditional measuring instruments have few selectable output measurement voltage points, which cannot meet the applications in various electrical insulation measurement fields.

Contents of the invention

The object of the present invention is to address the deficiencies of the prior art, and provide a method for measuring insulation resistance supporting output voltage at any point, and a measuring device for implementing the method. By adding a software-adjustable base accurate generation module circuit and a precise negative feedback module circuit, combined with the auxiliary control of functional software, the main control chip can output PWM signals, send the PWM signals to the reference generation module circuit to generate reference signals, and realize software compensate.

The technical scheme that the present invention adopts for realizing the above object is:

A method for measuring insulation resistance supporting output voltage at any point, comprising the following steps:

(1) A main control chip is set in the measurement circuit, and functional software is embedded in the main control chip. The user selects any point to measure the voltage through the functional software, and the functional software sends a selection signal, and the main control chip passes through the functional software. The transmitted selection signal identifies the insulation resistance voltage that the user needs to measure;

(2) a reference generation module connected to the main control chip described in step (1) is set, and the reference generation module is controlled by the main control chip to output a high-voltage reference signal;

(3) A high-voltage inverter generating module and a precise negative feedback circuit module connected to each other with the reference generating module described in step (2) are set, and the high-voltage reference signal described in step (2) enters the high-voltage inverter generating module, and the high-voltage The inverter generation module performs inverter high-magnification amplification on the high-voltage reference signal, and outputs the required high-voltage measurement signal, and the high-voltage measurement signal passes through the precise negative feedback circuit module to stably output the high-voltage measurement signal;

(4) a high-voltage attenuation circuit module and a loop current sampling module connected respectively to the high-voltage inverter generation module described in step (3) are set, and the insulation resistance measurement voltage is collected by the high-voltage attenuation circuit module, and the insulation resistance measurement voltage is output signal, collect the insulation resistance measurement current through the loop current sampling module, and output the insulation resistance measurement current signal;

(5) a low-pass filter connected to the high-voltage attenuation circuit module and the loop current sampling module described in step (4) is set, and the insulation resistance measurement voltage signal and the insulation resistance measurement current signal of the step (4) pass through the low-pass filter Filter to filter;

(6) set a low-pass filter described in step (5) and a precision analog-to-digital converter circuit module connected to the main control chip described in step (1), the insulation resistance of step (5) after filtering The measured voltage signal and the insulation resistance measured current signal are transmitted to the precision analog-to-digital converter circuit module for digital conversion of the signal, and then transmitted to the main control chip for software algorithm processing;

(7) A display module connected to the main control chip described in step (1) is provided, and the measurement results are output and displayed through the display module.

During the measurement process, the functional software completes the following tasks sequentially: read the high-voltage measurement signal, output the high-voltage attenuation signal after the high-voltage measurement signal is attenuated by the high-voltage attenuation circuit module, filter the high-voltage attenuation signal, and send it to the analog-to-digital conversion The device is sent to the main control chip to sample the high-voltage attenuation signal, and judge the sampled high-voltage attenuation signal to see if the output voltage meets the voltage signal output by the program preset conditions.

When the output voltage signal conforms to the preset conditions of the program, the insulation resistance is directly calculated; when the voltage signal output does not meet the preset conditions of the program, the software compensates and adjusts the corresponding pulse width modulation PWM signal, and finally reaches the required value. Output voltage measurement signal.

The functional software algorithm is provided with Ohm's law formula: R=V/I, and the functional software calculates the insulation resistance value according to the obtained insulation resistance measurement voltage and insulation resistance measurement current through the Ohm's law formula.

A measuring device for implementing the above-mentioned insulation resistance measuring method supporting output voltage at any point, which includes a measuring circuit, the circuit is provided with a main control chip connected to each other, a reference generating module, a high-voltage inverter generating module, and a precise negative feedback circuit module , high-voltage attenuation circuit module, same-channel current sampling module, low-pass filter, precision analog-to-digital converter circuit module and display module.

Functional software is embedded in the main control chip, and the software includes multiple built-in modules.

When the functional software is measuring, its built-in modules sequentially realize the following functions: read the high-voltage measurement signal, after the high-voltage measurement signal is attenuated by the high-voltage attenuation circuit module, output the high-voltage attenuation signal, filter the high-voltage attenuation signal, and send it to the module The digital converter is sent to the main control chip to sample the high-voltage attenuation signal, and judge the sampled high-voltage attenuation signal to see whether the output voltage meets the voltage signal output by the program preset conditions.

When the output voltage signal conforms to the preset conditions of the program, the insulation resistance is directly calculated; when the voltage signal output does not meet the preset conditions of the program, the software compensates and adjusts the corresponding pulse width modulation PWM signal, and finally reaches the required value. Output voltage measurement signal.

The functional software algorithm is provided with Ohm's law formula: R=V/I, and the functional software calculates the insulation resistance value according to the obtained insulation resistance measurement voltage and insulation resistance measurement current through the Ohm's law formula.

The beneficial effects of the present invention are: no mechanical method is used to select the output mode of voltage, but the method of hardware plus software is used to realize; and all voltage output points are realized through soft switches corresponding to soft. Add a software-adjustable base accurate generation module circuit and a precise negative feedback module circuit, adjust the reference signal corresponding to the output measurement voltage, and realize the voltage output at any point, and combine the auxiliary control of the functional software to enable the main control chip to output PWM signals. The PWM signal is sent to the reference generation module circuit to generate a reference signal, which realizes software compensation and makes the output measurement voltage more accurate.

Description of drawings

Fig. 1 is the constituent module schematic diagram of measuring circuit of the present invention;

Fig. 2 is a schematic diagram of the measurement flow of the present invention.

Detailed ways

Embodiment: Referring to Fig. 1 and Fig. 2, the insulation resistance measurement method supporting any point output voltage provided by this embodiment includes the following steps:

(1) A main control chip is set in the measurement circuit, and functional software is embedded in the main control chip. The user selects any point to measure the voltage through the functional software, and the functional software sends a selection signal, and the main control chip passes through the functional software. The transmitted selection signal identifies the insulation resistance voltage that the user needs to measure;

(2) further set a reference generation module connected with the main control chip described in step (1), control the reference generation module by the main control chip, output high voltage reference signal;

(3) A high-voltage inverter generation module and a precise negative feedback circuit module connected to each other with the reference generation module described in step (2) are further provided, and the high-voltage reference signal described in step (2) enters the high-voltage inverter generation module, The high-voltage inverter generation module performs inverter high-magnification amplification on the high-voltage reference signal, and outputs the required high-voltage measurement signal, and the high-voltage measurement signal passes through the precise negative feedback circuit module to stably output the high-voltage measurement signal;

(4) A high-voltage attenuation circuit module and a loop current sampling module connected respectively to the high-voltage inverter generation module described in step (3) are further provided, and the insulation resistance measurement voltage is collected by the high-voltage attenuation circuit module, and the insulation resistance measurement is output The voltage signal is used to collect the insulation resistance measurement current through the loop current sampling module, and output the insulation resistance measurement current signal;

(5) a low-pass filter connected to the high-voltage attenuation circuit module and the loop current sampling module described in step (4) is set again, and the insulation resistance measurement voltage signal and the insulation resistance measurement current signal described in step (4) pass through the low-pass filter filter through the filter;

(6) set one and step (5) described low-pass filter again, and step (1) described main control chip is connected with precision analog-to-digital converter circuit module, step (5) is insulated after filtering The resistance measurement voltage signal and the insulation resistance measurement current signal are transmitted to the precision analog-to-digital converter circuit module for digital conversion of the signal, and then transmitted to the main control chip for software algorithm processing;

(7) Finally, a display module connected to the main control chip described in step (1) is provided, through which the measurement results are output and displayed.

During the measurement process of the functional software, its built-in modules complete the following work in sequence: read the high-voltage measurement signal, after the high-voltage measurement signal is attenuated by the high-voltage attenuation circuit module, output the high-voltage attenuation signal, filter the high-voltage attenuation signal, and send it to The analog-to-digital converter is sent to the main control chip to sample the high-voltage attenuation signal, and judge the sampled high-voltage attenuation signal to see whether the output voltage meets the voltage signal output by the program preset conditions.

When the output voltage signal conforms to the preset conditions of the program, the insulation resistance is directly calculated; when the voltage signal output does not meet the preset conditions of the program, the software compensates and adjusts the corresponding pulse width modulation PWM signal, and finally reaches the required value. Output voltage measurement signal.

The functional software algorithm is provided with Ohm's law formula: R=V/I, and the functional software calculates the insulation resistance value according to the obtained insulation resistance measurement voltage and insulation resistance measurement current through the Ohm's law formula.

A measuring device for implementing the above-mentioned insulation resistance measuring method supporting output voltage at any point, which includes a measuring circuit, which is provided with a main control chip connected to each other, a reference generating module, a high-voltage inverter generating module, and a precise negative feedback Circuit module, high-voltage attenuation circuit module, loop current sampling module, low-pass filter, precision analog-to-digital converter circuit module and display module.

Functional software is embedded in the main control chip, and a plurality of functional modules are built in it.

When the functional software measures, its built-in multiple functional modules sequentially realize the following functions: read the high-voltage measurement signal, after the high-voltage measurement signal is attenuated by the high-voltage attenuation circuit module, output the high-voltage attenuation signal, and after filtering the high-voltage attenuation signal, Send it to the analog-to-digital converter and send it to the main control chip to sample the high-voltage attenuation signal, and judge the sampled high-voltage attenuation signal to see if the output voltage meets the voltage signal output by the program preset conditions.

When the output voltage signal conforms to the preset conditions of the program, the insulation resistance is directly calculated; when the voltage signal output does not meet the preset conditions of the program, the software compensates and adjusts the corresponding pulse width modulation PWM signal, and finally reaches the required value. Output voltage measurement signal. The functional software algorithm is provided with Ohm's law formula: R=V/I, and the functional software calculates the insulation resistance value according to the obtained insulation resistance measurement voltage and insulation resistance measurement current through the Ohm's law formula.

However, the above description is only a preferred feasible embodiment of the present invention, and is not intended to limit the patent scope of the present invention, so all equivalent structural changes made by using the description of the present invention and the contents of the accompanying drawings are included in the protection scope of the present invention Inside.

Claims (9)

1. support an insulation measurement method for arbitrfary point output voltage, it is characterized in that, it comprises the following steps:

(1) main control chip is set in metering circuit, and be embedded in functional software at this main control chip, user is by this functional software, select arbitrfary point measuring voltage, functional software sends selection signal, the selection signal that described main control chip is transmitted by functional software, identifies the required insulation resistance voltage measured of user;

(2) a benchmark generation module be connected with step (1) described main control chip is set, controls benchmark generation module by main control chip, export high voltage reference signal;

(3) the high-voltage inverted generation module be connected to each other mutually with step (2) described benchmark generation module and accurate negative-feedback circuit module are set, the described high voltage reference signal of step (2), enter in this high-voltage inverted generation module, high-voltage inverted generation module is to high voltage reference signal, do inversion magnification at high multiple, and the high-tension measurement signal needed for exporting, high-tension measurement signal makes high-tension measurement signal stabilization export by described accurate negative-feedback circuit module again;

(4) the high pressure attenuator circuit module be connected respectively with the described high-voltage inverted generation module of step (3) and loop current sampling module are set, by described high pressure attenuator circuit module acquires insulation measurement voltage, and export insulation measurement voltage signal, gather insulation measurement electric current by loop current sampling module, and export insulation measurement current signal;

(5) arrange a low-pass filter be connected with loop current sampling module with step (4) described high pressure attenuator circuit module, the insulation measurement voltage signal described in step (4) and insulation measurement current signal carry out filtering by this low-pass filter;

(6) one and step (5) described low-pass filter are set, and the accurate analog-digital converter circuit module that step (1) described main control chip is connected, by the insulation measurement voltage signal of step (5) after filtering process and insulation measurement current signal, transfer to this accurate analog-digital converter circuit module, carry out the digital conversion of signal, then transfer to main control chip, carry out software algorithm process;

(7) display module be connected with step (1) described main control chip is set, by this display module, by measurement result output display.

2. the insulation measurement method of support arbitrfary point according to claim 1 output voltage, it is characterized in that, described functional software is in measuring process, complete following work successively: read high-tension measurement signal, high-tension measurement signal is after the decay of high pressure attenuator circuit module, export high pressure deamplification, after filtering is carried out to this high pressure deamplification, deliver to analog to digital converter and send into main control chip, high pressure deamplification is sampled, the high pressure deamplification that sampling is returned is judged, whether output voltage is in order the voltage signal of pre-conditioned output.

3. the insulation measurement method of support arbitrfary point according to claim 2 output voltage, is characterized in that, when the voltage signal of pre-conditioned output of being in order, then directly to calculate insulation resistance; When the voltage signal of the pre-conditioned output of the program that do not meet, software compensates, and adjustment corresponding pulses width modulated pwm signal, finally reaches required output voltage measuring-signal.

4. the insulation measurement method of support arbitrfary point according to claim 1 output voltage, it is characterized in that, Ohm law formula is provided with: R=V/I in described functional software, functional software, according to the insulation measurement voltage obtained and insulation measurement electric current, draws insulating resistance value by this Ohm law formula operation.

5. one kind implements the claims the measurement mechanism of the insulation measurement method of the support arbitrfary point output voltage described in 1, it is characterized in that, it comprises a metering circuit, is provided with interconnective main control chip, benchmark generation module, high-voltage inverted generation module, precisely negative-feedback circuit module, high pressure attenuator circuit module, loop current sampling module, low-pass filter, precisely analog-digital converter circuit module and display module in this circuit.

6. the measurement mechanism of the insulation measurement method of support arbitrfary point according to claim 5 output voltage, is characterized in that, be embedded in functional software at described main control chip, this software comprises multiple built-in module.

7. the measurement mechanism of the insulation measurement method of support arbitrfary point according to claim 6 output voltage, it is characterized in that, described functional software is when measuring, its built-in module realizes following function successively: read high-tension measurement signal, high-tension measurement signal is after the decay of high pressure attenuator circuit module, export high pressure deamplification, after filtering is carried out to this high pressure deamplification, deliver to analog to digital converter and send into main control chip, high pressure deamplification is sampled, the high pressure deamplification that sampling is returned is judged, whether output voltage is in order the voltage signal of pre-conditioned output.

8. the measurement mechanism of the insulation measurement method of support arbitrfary point according to claim 7 output voltage, is characterized in that, when the voltage signal of pre-conditioned output of being in order, then directly to calculate insulation resistance; When the voltage signal of the pre-conditioned output of the program that do not meet, software compensates, and adjustment corresponding pulses width modulated pwm signal, finally reaches required output voltage measuring-signal.

9. the measurement mechanism of the insulation measurement method of support arbitrfary point according to claim 6 output voltage, it is characterized in that, Ohm law formula is provided with: R=V/I in described functional software algorithm, functional software, according to the insulation measurement voltage obtained and insulation measurement electric current, draws insulating resistance value by this Ohm law formula operation.