CN106645959A - Measuring circuit and method for insulation resistance of DC charging pile - Google Patents
Measuring circuit and method for insulation resistance of DC charging pile Download PDFInfo
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- CN106645959A CN106645959A CN201610992567.0A CN201610992567A CN106645959A CN 106645959 A CN106645959 A CN 106645959A CN 201610992567 A CN201610992567 A CN 201610992567A CN 106645959 A CN106645959 A CN 106645959A
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- resistance
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/10—Technologies relating to charging of electric vehicles
- Y02T90/12—Electric charging stations
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention discloses a measuring circuit and method for the insulation resistance of a DC charging pile. The measuring circuit comprise a first isolation and voltage conditioning circuit U1 and a second isolation and voltage conditioning circuit U2, the first isolation and voltage conditioning circuit U1 is connected with a bus of the DC charging pile via a first potential-divider network, the second isolation and voltage conditioning circuit U2 is connected with the bus of the DC charging pile via a second potential-divider network, the output end of the first isolation and voltage conditioning circuit U1 serves as a first measuring point, and the output end of the second isolation and voltage conditioning circuit U2 serves as a second measuring point. Before charging of the DC charging pile, the insulation resistance between the DC bus of the DC charging pile and the ground is measured to determine an insulation condition of the DC charging pile, the using safety of the DC charging pile is ensured, the circuit is simple, test operation is convenient, realization is easy, the reliability is high, and the measuring circuit and method have good application prospects.
Description
Technical field
The present invention relates to circuit measuring technical field, and in particular to a kind of measurement electricity for direct-current charging post insulation resistance value
Road and method.
Background technology
Be applied to more and more widely in daily life as clean energy resource in electric energy instantly, such as electric automobile it is general
And wait, therefore, matched charging pile is also disposed on a large scale, particularly direct-current charging post, because of its charging rate soon, and
It is used widely.It is safe in order to ensure using for direct-current charging post because direct-current charging post can be chronically exposed to open air, logical
Before crossing direct-current charging post charging, it is necessary to which its situation of insulating is detected, at present, also fill without reliable means direct current on the market
The insulation situation of electric stake is detected, is the problem for being currently needed for solving.
The content of the invention
The purpose of the present invention is to overcome the insulation situation without reliable means direct-current charging post in prior art to be examined
Survey, make direct-current charging post there is a problem of potential safety hazard.The present invention for direct-current charging post insulation resistance value measuring circuit and
Method, before being charged by direct-current charging post, can be measured the dc bus of direct-current charging post and be sentenced with the insulation resistance value of the earth
The insulation situation of disconnected direct-current charging post, it is ensured that using for direct-current charging post is safe, and circuit is simple, and test operation is convenient, easily in fact
Existing, reliability is high, has a good application prospect.
In order to achieve the above object, the technical solution adopted in the present invention is：
A kind of measuring circuit for direct-current charging post insulation resistance value, including the first isolation and voltage modulate circuit U1, the
Two isolation and voltage modulate circuit U2,
The positive input terminal of first isolation and voltage modulate circuit U1 passes through resistance R1 with direct-current charging post bus just
Pole is connected, and the negative input end of first isolation and voltage modulate circuit U1 is negative with direct-current charging post bus by resistance R6
Pole is connected, and between first isolation and the positive and negative input of voltage modulate circuit U1 resistance R4, the resistance are parallel with
R1, resistance R4, resistance R6 constitute the first potential-divider network；
The positive input terminal of second isolation and voltage modulate circuit U2 passes sequentially through resistance R3, resistance R2 and DC charging
The positive pole of stake bus is connected, and the negative input end of second isolation and voltage modulate circuit U2 passes sequentially through resistance R8, resistance
R7 is connected with the negative pole of direct-current charging post bus, between second isolation and the positive and negative input of voltage modulate circuit U2
Resistance R5 is parallel with, the resistance R3, the connecting node of resistance R2 are connected by switch S1 with the earth, the resistance R8, resistance
The connecting node of R7 is connected by switch S2 with the earth, the resistance R2, resistance R3, resistance R5, resistance R7, resistance R8 compositions the
Two potential-divider networks；
The output end of first isolation and voltage modulate circuit U1 is used as the first measurement point, second isolation and voltage
The output end of modulate circuit U2 is used as the second measurement point.
A kind of aforesaid measuring circuit for direct-current charging post insulation resistance value, the switch S1, switch S2 can by after
The node of electrical equipment replaces.
Measuring method based on a kind of above-mentioned measuring circuit for direct-current charging post insulation resistance value, it is characterised in that：
Before charging by direct-current charging post, the dc bus of direct-current charging post and the insulation resistance value of the earth are measured, are comprised the following steps,
Step (1), measures the voltage Uadc of the first measurement point, and according to the resistance ratio of the first potential-divider network, by public affairs
Formula (1), is calculated bus voltage value Umx of direct-current charging post bus；
Uadc*K1=(Umx*R4)/(R1+R4+R6) (1)
After simplification,
Umx=(Uadc*K1) * (R1+R4+R6)/R4
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；
Step (2), if the positive and negative electrode of direct-current charging post bus is respectively Rx, Ry to the resistance of the earth, controlling switch S1 elder generation
Closure, then disconnect switch S2；
Step (3), measures voltage U ＇ adc, the voltage Uadc1 of the second measurement point of current first measurement point, by first
The resistance ratio of potential-divider network, the second potential-divider network, obtains equation (2)
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；K2 is that the first isolation and voltage are adjusted
The voltage amplification factor of reason circuit U 2；// it is resistor coupled in parallel symbol；
U ＇ mx are the bus voltage value for measuring the U ＇ adc and Uadc1 moment；
Step (4), controlling switch S1 first disconnects, is closed again switch S2；
Step (5), measures voltage U " adc, the voltage U ＇ adc1 of the second measurement point, by first of current first measurement point
The resistance ratio of potential-divider network, the second potential-divider network, obtains equation (3)
Wherein, the bus voltage value at U " mx is measurement U " adc and U ＇ adc1 moment；
Step (6), by equation (2), equation (3) the linear equation in two unknowns group with regard to Rx, Ry is constituted, and calculates parsing
Go out the resistance of Rx, Ry；
Step (7), according to the resistance of Rx, Ry, judges the insulation situation of direct-current charging post, if Rx/Umx or Ry/Umx are big
When 500 Ω/V, direct-current charging post insulation situation is normal, can normally use；If Rx/Umx or Ry/Umx is less than 500 Ω/V
When, direct-current charging post triggering warning information；If Rx/Umx or Ry/Umx is less than 100 Ω/V, direct-current charging post triggering insulation
Fault message.
The invention has the beneficial effects as follows：The measuring circuit and method for direct-current charging post insulation resistance value of the present invention, energy
Enough before charging by direct-current charging post, measure the dc bus of direct-current charging post with the insulation resistance value of the earth to judge direct current
The insulation situation of charging pile, it is ensured that using for direct-current charging post is safe, and circuit is simple, and test operation is convenient, easily realization, reliability
Property it is high, have a good application prospect.
Description of the drawings
Fig. 1 is the circuit theory diagrams of the measuring circuit for direct-current charging post insulation resistance value of the present invention.
Specific embodiment
Below in conjunction with Figure of description, the present invention is further illustrated.
As shown in figure 1, the measuring circuit for direct-current charging post insulation resistance value of the present invention, including the first isolation and voltage
Modulate circuit U1, the second isolation and voltage modulate circuit U2, the first isolation and voltage modulate circuit U1 pass through the first potential-divider network
With being connected for direct-current charging post bus, the first isolation and voltage modulate circuit U2 are by the second potential-divider network and direct-current charging post
Bus is connected, and concrete downlink connection relation is as follows：
The positive input terminal of first isolation and voltage modulate circuit U1 passes through resistance R1 with direct-current charging post bus just
Pole is connected, and the negative input end of first isolation and voltage modulate circuit U1 is negative with direct-current charging post bus by resistance R6
Pole is connected, and between first isolation and the positive and negative input of voltage modulate circuit U1 resistance R4, the resistance are parallel with
R1, resistance R4, resistance R6 constitute the first potential-divider network；
The positive input terminal of second isolation and voltage modulate circuit U2 passes sequentially through resistance R3, resistance R2 and DC charging
The positive pole of stake bus is connected, and the negative input end of second isolation and voltage modulate circuit U2 passes sequentially through resistance R8, resistance
R7 is connected with the negative pole of direct-current charging post bus, between second isolation and the positive and negative input of voltage modulate circuit U2
Resistance R5 is parallel with, the resistance R3, the connecting node of resistance R2 are connected by switch S1 with the earth (PE), the resistance R8,
The connecting node of resistance R7 is connected by switch S2 with the earth (PE), the resistance R2, resistance R3, resistance R5, resistance R7, resistance
R8 constitutes the second potential-divider network；
The output end of first isolation and voltage modulate circuit U1 is used as the first measurement point, second isolation and voltage
The output end of modulate circuit U2 is used as the second measurement point.
The switch S1, switch S2 can be replaced by the node of relay, without the need for artificial operation, improve automaticity,
Increase safety and reliability.
First isolation and voltage modulate circuit U1, the second isolation and voltage modulate circuit U2 adopt people in the art
The conventional isolation circuit of member, voltage amplifier circuit, voltage collection circuit build.
Based on the measuring method of the measuring circuit of above-mentioned direct-current charging post insulation resistance value, charged by direct-current charging post
Before, the dc bus of direct-current charging post and the insulation resistance value of the earth are measured, comprise the following steps,
Step (1), measures the voltage Uadc of the first measurement point, and according to the resistance ratio of the first potential-divider network, by public affairs
Formula (1), is calculated bus voltage value Umx of direct-current charging post bus；
Uadc*K1=(Umx*R4)/(R1+R4+R6) (1)
After simplification,
Umx=(Uadc*K1) * (R1+R4+R6)/R4
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；
Step (2), if the positive and negative electrode of direct-current charging post bus is respectively Rx, Ry to the resistance of the earth, controlling switch S1 elder generation
Closure, then disconnect switch S2；
Step (3), measures voltage U ＇ adc, the voltage Uadc1 of the second measurement point of current first measurement point, by first
The resistance ratio of potential-divider network, the second potential-divider network, obtains equation (2)
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；K2 is that the first isolation and voltage are adjusted
The voltage amplification factor of reason circuit U 2；// it is resistor coupled in parallel symbol；
U ＇ mx are the bus voltage value for measuring the U ＇ adc and Uadc1 moment；
Step (4), controlling switch S1 first disconnects, is closed again switch S2；
Step (5), measures voltage U " adc, the voltage U ＇ adc1 of the second measurement point, by first of current first measurement point
The resistance ratio of potential-divider network, the second potential-divider network, obtains equation (3)
Wherein, the bus voltage value at U " mx is measurement U " adc and U ＇ adc1 moment；
Step (6), by equation (2), equation (3) the linear equation in two unknowns group with regard to Rx, Ry is constituted, and calculates parsing
Go out the resistance of Rx, Ry；
Step (7), according to the resistance of Rx, Ry, judges the insulation situation of direct-current charging post, if Rx/Umx or Ry/Umx are big
When 500 Ω/V, direct-current charging post insulation situation is normal, can normally use；If Rx/Umx or Ry/Umx is less than 500 Ω/V
When, direct-current charging post triggering warning information；If Rx/Umx or Ry/Umx is less than 100 Ω/V, direct-current charging post triggering insulation
Fault message.
In sum, measuring circuit and method for direct-current charging post insulation resistance value of the invention, can be by straight
Before current charge stake is charged, measure the dc bus of direct-current charging post with the insulation resistance value of the earth to judge the exhausted of direct-current charging post
Edge situation, and by the d-c bus voltage value of two potential-divider network synchro measure direct-current charging posts, so as to improve certainty of measurement,
Ensure the safety that uses of direct-current charging post, circuit is simple, and test operation is convenient, easily realization, and reliability is high, should with good
Use prospect.
General principle, principal character and the advantage of the present invention has been shown and described above.The technical staff of the industry should
Understand, the present invention is not restricted to the described embodiments, the original for simply illustrating the present invention described in above-described embodiment and specification
Reason, without departing from the spirit and scope of the present invention, the present invention also has various changes and modifications, these changes and improvements
Both fall within scope of the claimed invention.The claimed scope of the invention is by appending claims and its equivalent circle.
It is fixed.
Claims (3)
1. a kind of measuring circuit for direct-current charging post insulation resistance value, it is characterised in that：Including the first isolation and voltage conditioning
Circuit U 1, second is isolated and voltage modulate circuit U2,
The positive input terminal of first isolation and voltage modulate circuit U1 passes through the positive pole phase of resistance R1 and direct-current charging post bus
The negative input end of connection, first isolation and voltage modulate circuit U1 passes through the negative pole phase of resistance R6 and direct-current charging post bus
Connection, between first isolation and the positive and negative input of voltage modulate circuit U1 resistance R4, the resistance R1, electricity are parallel with
Resistance R4, resistance R6 constitute the first potential-divider network；
The positive input terminal of second isolation and voltage modulate circuit U2 passes sequentially through resistance R3, resistance R2 and direct-current charging post is female
The positive pole of line is connected, it is described second isolation and voltage modulate circuit U2 negative input end pass sequentially through resistance R8, resistance R7 with
The negative pole of direct-current charging post bus is connected, in parallel between second isolation and the positive and negative input of voltage modulate circuit U2
Have a resistance R5, the resistance R3, resistance R2 connecting node by switch S1 be greatly connected, the resistance R8, resistance R7
Connecting node is connected by switch S2 with the earth, and the resistance R2, resistance R3, resistance R5, resistance R7, resistance R8 constitute second point
Pressure network network；
The output end of first isolation and voltage modulate circuit U1 is used as the first measurement point, second isolation and voltage conditioning
The output end of circuit U 2 is used as the second measurement point.
2. a kind of measuring circuit for direct-current charging post insulation resistance value according to claim 1, it is characterised in that：It is described
Switch S1, switch S2 can be replaced by the node of relay.
3. the measurement side of described a kind of measuring circuit for direct-current charging post insulation resistance value of any one of claim 1-2 is based on
Method, it is characterised in that：Before being charged by direct-current charging post, the insulation of the dc bus and the earth that measure direct-current charging post hinders
Value, comprises the following steps,
Step (1), measures the voltage Uadc of the first measurement point, and according to the resistance ratio of the first potential-divider network, by formula
(1), it is calculated bus voltage value Umx of direct-current charging post bus；
Uadc*K1=(Umx*R4)/(R1+R4+R6) (1)
After simplification,
Umx=(Uadc*K1) * (R1+R4+R6)/R4
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；
Step (2), if the positive and negative electrode of direct-current charging post bus is respectively Rx, Ry to the resistance of the earth, controlling switch S1 is first closed
Close, then disconnect switch S2；
Step (3), measures voltage U ＇ adc, the voltage Uadc1 of the second measurement point of current first measurement point, by the first partial pressure
The resistance ratio of network, the second potential-divider network, obtains equation (2)
Wherein, K1 is the voltage amplification factor of the first isolation and voltage modulate circuit U1；K2 is the first isolation and voltage conditioning electricity
The voltage amplification factor of road U2；// it is resistor coupled in parallel symbol；U ＇ mx are the bus voltage value for measuring the U ＇ adc and Uadc1 moment；
Step (4), controlling switch S1 first disconnects, is closed again switch S2；
Step (5), measures voltage U " adc, the voltage U ＇ adc1 of the second measurement point, by the first partial pressure of current first measurement point
The resistance ratio of network, the second potential-divider network, obtains equation (3)
Wherein, the bus voltage value at U " mx is measurement U " adc and U ＇ adc1 moment；
Step (6), by equation (2), equation (3) the linear equation in two unknowns group with regard to Rx, Ry is constituted, and calculating is parsed
The resistance of Rx, Ry；
Step (7), according to the resistance of Rx, Ry, judges the insulation situation of direct-current charging post, if Rx/Umx or Ry/Umx are more than
During 500 Ω/V, direct-current charging post insulation situation is normal, can normally use；If Rx/Umx or Ry/Umx is less than 500 Ω/V,
Direct-current charging post triggers warning information；If Rx/Umx or Ry/Umx is less than 100 Ω/V, direct-current charging post triggering insulation fault
Information.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610992567.0A CN106645959B (en) | 2016-11-09 | 2016-11-09 | Measuring circuit and method for insulation resistance of direct current charging pile |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610992567.0A CN106645959B (en) | 2016-11-09 | 2016-11-09 | Measuring circuit and method for insulation resistance of direct current charging pile |
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| CN106645959A true CN106645959A (en) | 2017-05-10 |
| CN106645959B CN106645959B (en) | 2023-04-18 |
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2016
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