Insulation detection method for charging device

Abstract

The present invention discloses an insulation detection method for a charging device, comprising the following steps: A1, after the electric vehicle is connected to the charging pile, the charging pile starts to perform insulation detection, and respectively measures the DC+ to ground impedance R+ and the DC- to ground impedance R-; A2, accumulating the number of insulation detection times n, and respectively calculating the difference Δ between the measured R+, R- and the insulation impedance standard value r R+ , Δ R‑ , and then calculate Δ R+ , Δ R‑ The square values ​​of each are saved; A3, respectively R+ , Δ R‑ The square value of each and the total square of DC+ to ground resistance S R+ 、DC-to-ground resistance total square sum S R‑ Accumulate and assign the accumulated values ​​to S respectively R+ , S R‑ ; A4, then calculate the standard deviation S of DC+ impedance to ground 正 , Standard deviation of DC-to-ground impedance S 负 , and according to the calculated S 正 , S 负 The present invention can effectively avoid the risk of electric shock caused by aging of insulating materials during charging.

Description

Technical Field

[0001] The present invention relates to the technical field related to insulation detection of charging piles, and in particular to an insulation detection method for a charging device. Background Art

[0002] The insulating material of the charging pile will slowly age with its service life, resulting in a gradual decline in its insulation performance. If the insulation performance of the charging pile is poor, there is a risk of electric shock accidents, and it will also affect its normal charging work. Most of the existing charging piles perform insulation testing before charging, and then use this to determine whether it is suitable for subsequent charging operations. However, this method cannot intuitively obtain the aging of the insulating material. Insulation testing before charging can only determine the current insulation condition. During the charging process, there is still a risk of electric shock caused by the aging of the insulating material. To this end, we propose an insulation detection method for a charging device. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide an insulation detection method for a charging device.

[0004] To achieve the above object, the present invention adopts the following technical solution: an insulation detection method for a charging device, comprising the following steps:

[0005] A1. After the electric vehicle is connected to the charging pile, the charging pile starts insulation testing, measuring the DC+ to ground impedance R+ and the DC- to ground impedance R- respectively;

[0006] A2. Each time the charging pile is connected to the electric vehicle, the value of the insulation test number n is automatically increased by one, and n≥1, and n is counted from the time the charging pile leaves the factory; then the measured R+ and positive insulation resistance standard values ​​r are calculated respectively. + The difference Δ R+ , the measured R- and negative insulation resistance standard value r - The difference Δ R- , and then calculate Δ R+ , Δ R- The respective square values ​​are saved;

[0007] Δ R+ = r + - R+ ; Δ R- = r - - R-;

[0008] A3, respectively R+ , Δ R- The square value of each and the total square of DC+ to ground resistance S R+ 、DC-total square sum of ground resistance SR- Accumulate, then there is an intermediate value S1= (Δ R+ ) 2 + S R+ , S2= (Δ R- ) 2 + S R- , and assign the accumulated values ​​to S respectively. R+ , S R- ; That is S R+ = S1, S R- = S2;

[0009] A4. Then calculate the standard deviation S of DC+ impedance to ground respectively 正 , Standard deviation of DC-to-ground impedance S 负 , and according to the calculated S 正 , S 负 To judge the insulation performance of the charging pile;

[0010] The calculation formula of standard deviation S is: .

[0011] The beneficial effect of the present invention is that the present invention can accurately obtain the insulation performance of the insulation material of the charging pile, and effectively avoid the risk of electric shock caused by aging of the insulation material during the charging process. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in further detail below.

[0013] An insulation detection method for a charging device comprises the following steps:

[0014] A1. After the electric vehicle is connected to the charging pile, the charging pile starts insulation testing, measuring the DC+ to ground impedance R+ and the DC- to ground impedance R- respectively;

[0015] A2. Each time the charging pile is connected to the electric vehicle, the value of the insulation test number n is automatically increased by one, and n≥1, and n is counted from the time the charging pile leaves the factory; then the measured R+ and positive insulation resistance standard values ​​r are calculated respectively. + The difference Δ R+ , the measured R- and negative insulation resistance standard value r - The difference Δ R- , and then calculate Δ R+ , Δ R- The respective square values ​​are saved; Δ R+ = r + - R+ ; Δ R- = r - - R-;

[0016] A3, respectively R+ , Δ R- The square value of each and the total square of DC+ to ground resistance S R+ 、DC-total square sum of ground resistance S R- Accumulate, then there is an intermediate value S1= (Δ R+ ) 2 + S R+ , S2= (Δ R- ) 2 + S R- , and assign the accumulated values ​​to S respectively. R+ , S R- , S R+ = S1, S R- = S2;

[0017] A4. Then calculate the standard deviation S of DC+ impedance to ground respectively 正 , Standard deviation of DC-to-ground impedance S 负 , and according to the calculated S 正 , S 负 To judge the insulation performance of the charging pile. Standard deviation S 正 The calculation formula is , standard deviation S 负 The calculation formula is .

[0018] In the calculation of S 正 and S 负 Afterwards, S 正 , S 负 Compared with the insulation performance standard difference S of the charging pile itself. The greater the difference between it and S, the more unstable the insulation performance of the insulation material and the more serious the aging of the insulation material. When the difference between it and S reaches the threshold, the entire charging pile needs to be shut down and the corresponding insulation material needs to be replaced, so as to prevent the occurrence of insulation leakage, take precautions before it happens, and effectively avoid the risk of electric shock caused by aging of insulation materials during charging.

[0019] The above description does not limit the technical scope of the present invention in any way. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An insulation detection method for a charging device, characterized in that: The following steps are included: A1. After the electric vehicle is connected to the charging pile, the charging pile starts insulation testing, measuring the DC+ to ground impedance R+ and the DC- to ground impedance R- respectively; A2. Each time the charging pile is connected to the electric vehicle, the value of the insulation test number n is automatically increased by one, and n≥1, and n is counted from the time the charging pile leaves the factory; then the measured R+ and positive insulation resistance standard values ​​r are calculated respectively. + The difference Δ R+ , the measured R- and negative insulation resistance standard value r - The difference Δ R- , and then calculate Δ R+ , Δ R- The respective square values ​​are saved; D R+ = r + - R+;D R- = r - - R-; A3, respectively R+ , Δ R- The square value of each and the total square of DC+ to ground resistance S R+ 、DC-total square sum of ground resistance S R- Accumulate, then there is an intermediate value S1= (Δ R+ ) 2 + S R+ , S2= (Δ R- ) 2 + S R- , and assign the accumulated values ​​to S respectively. R+ , S R- ; That is S R+ = S1, S R- = S2; A4. Then calculate the standard deviation S of DC+ impedance to ground respectively 正 , Standard deviation of DC-to-ground impedance S 负 , and according to the calculated S 正 , S 负 To judge the insulation performance of the charging pile; Standard Deviation 正 The calculation formula is .