CN202870174U - Low energy consumption circuit for detecting insulating resistance of DC bus - Google Patents
Low energy consumption circuit for detecting insulating resistance of DC bus Download PDFInfo
- Publication number
- CN202870174U CN202870174U CN 201220562588 CN201220562588U CN202870174U CN 202870174 U CN202870174 U CN 202870174U CN 201220562588 CN201220562588 CN 201220562588 CN 201220562588 U CN201220562588 U CN 201220562588U CN 202870174 U CN202870174 U CN 202870174U
- Authority
- CN
- China
- Prior art keywords
- resistance
- ground wire
- bus
- bridge
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn - After Issue
Links
Images
Landscapes
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The utility model relates to the field of DC bus insulating resistance detection, in particular to a low energy consumption circuit and a method for detecting the insulating resistance of a DC bus, wherein the circuit comprises a balance bridge, an unbalance bridge and a voltage sampling circuit used for detecting a voltage value between positive and negative buses and a ground line; also comprising a switch K for controlling the switching on and off of the upper and lower bridge arms of the balance bridge. In the process of detection, the upper and lower bridge arms of the balance bridge are switched on only in the process of balance bridge detection, such that an current passes through the balance bridge only in the process of balance bridge detection, and no current passes through the balance bridge in other time, thereby enabling the power consumption to be zero, and reducing the total power consumption of the system.
Description
Technical field
The utility model relates to dc bus insulation resistance detection field, refers to especially a kind of dc bus insulating resistor detecting circuit and detection method of low energy consumption.
Background technology
Because the dc bus insulativity descends and dc bus ground connection is the DC power system most common failure, therefore in time grasp the DC power system bus insulating property, when the dc bus insulation resistance dropped to setting value, Insulation Inspection System is the notice host computer in time, sends sound and light alarm etc.Existing detection method has the bridge balance detection method, but the situation that the method positive and negative busbar insulating resistance is descended in proportion is helpless.Therefore, derived " balance-imbalance " electric bridge detection method.For " balance-imbalance " electric bridge detection method, generally be that the access balanced bridge detects in circuit, increasing non-equilibrium bridge on the basis of balance bridge after the balance bridge detection is finished detects, have equally some problems for this a kind of detection method: existing detection method balance bridge in testing process need to keep on-state, and the resistance in the balance bridge is generally power resistor, and resistance is little, be series at for a long time between positive and negative and the ground, produced a large amount of electric energy losses, cause the DC power system power consumption larger, waste energy.
Summary of the invention
The purpose of this utility model is to avoid above-mentioned weak point of the prior art and provides a kind of Heng Qiao that can avoid to continue to connect, and reduces dc bus insulation resistance voltage sampling circuit and the detection method of system energy consumption.
The purpose of this utility model is achieved through the following technical solutions:
A kind of low energy consumption dc bus insulating resistor detecting circuit is provided, comprise balance bridge, non-equilibrium bridge and for detection of the voltage sampling circuit of magnitude of voltage between positive and negative busbar and the ground wire, the upper brachium pontis of described balance bridge and the upper brachium pontis of non-equilibrium bridge are arranged in parallel between the positive bus-bar and ground wire of circuit to be checked, the lower brachium pontis of described balance bridge and the lower brachium pontis of non-equilibrium bridge are arranged in parallel between the negative busbar and ground wire of circuit to be checked, it is characterized in that: comprise also whether the upper brachium pontis of controlling non-equilibrium bridge accesses between positive bus-bar and the ground wire and whether lower brachium pontis accesses K switch 3 between negative busbar and the ground wire, also comprise the K switch of the upper brachium pontis of controlling balance bridge and the simultaneously conducting of lower brachium pontis/disconnect simultaneously.
Wherein, the upper brachium pontis of described balance bridge comprises the resistance R 0 that is serially connected with between positive bus-bar and the ground wire, the lower brachium pontis of described balance bridge comprises the resistance R 1 that equates with resistance R 0 resistance that is serially connected with between negative busbar and the ground wire, and described K switch comprises the K switch 1 of connecting with R0 and the K switch 2 of connecting with R1.
Wherein, described non-equilibrium bridge comprises resistance R 2 and the resistance R 3 that is serially connected with between the positive and negative busbar, and the tie point of described resistance R 2 and R3 is as the voltage non-zero points.
Wherein, described voltage sampling circuit comprises being serially connected with respectively between positive bus-bar and the ground wire and will detect resistance R 4, and the detection resistance R 5 that equates with resistance R 4 resistances between negative busbar and the ground wire.
Wherein, described non-equilibrium bridge comprises resistance R 2 and the resistance R 3 that is serially connected with between the positive and negative busbar, and described resistance R 2 is connected tie point and is connected with ground wire by K switch 3 with R3, and described resistance R 2 resistance R 3 satisfy formula
, wherein Δ u is voltage fluctuation tolerance interval value, V is the magnitude of voltage between the positive and negative busbar.
A kind of dc bus insulation resistance detection method is provided, it is characterized in that: comprise step:
A. disconnect being connected of balance bridge and bus and being connected of non-equilibrium bridge and ground wire, obtain voltage Vx between this moment positive bus-bar and ground wire and the voltage Vy between negative busbar and the ground wire, judge whether Vx or Vy have one to be zero, if, then report to the police and stop to detect, if not, then preserve Vx and/or Vy data;
B. the non-equilibrium bridge of conducting and ground wire is connected, the disconnection balance bridge is connected with ground wire, obtain voltage Vx1 between this moment positive bus-bar and ground wire and the voltage Vy1 between negative busbar and the ground wire, judge whether Vx1=Vx or Vy1=Vy, if, then report to the police and stop to detect, if not, then preserve Vx1 and Vy1 data;
C. being connected of conducting balance bridge and bus disconnects being connected of non-equilibrium bridge and ground wire, obtain this moment positive bus-bar and ground wire between voltage Vx2 and the voltage Vy2 between negative busbar and the ground wire, preserve Vx2 and Vy2 data;
D. utilize Vx1, Vy1, Vx2, Vy2, R0, the insulation resistance Rx between R2, R3, R4, R5 calculating positive bus-bar and the ground wire and the voltage insulation resistance R y between negative busbar and the ground wire.Wherein: R0 is the upper brachium pontis of balance bridge of testing circuit or the resistance value of lower brachium pontis, R2 is the resistance value of upper brachium pontis of the non-equilibrium bridge of testing circuit, R3 be testing circuit non-equilibrium bridge lower brachium pontis or resistance value, R4 is the resistance value of voltage sampling circuit between positive bus-bar and ground wire of testing circuit, and R5 is the resistance value of voltage sampling circuit between negative busbar and ground wire of testing circuit.
E. will calculate the positive bus-bar of gained and the insulation resistance Rx between the ground wire and voltage insulation resistance R y and the preset value between negative busbar and the ground wire and compare, if Rx or Ry then report to the police less than preset value.
Wherein, the acquisition methods of the voltage Vy between the positive bus-bar in the described steps A and the voltage Vx between the ground wire and negative busbar and the ground wire is: obtain voltage V between the positive and negative busbar and the voltage Vy between Vy negative busbar and the ground wire, described Vx=V-|Vy|; The acquisition methods of voltage Vy1 between positive bus-bar among the described step B and the voltage Vx1 between the ground wire and negative busbar and the ground wire is: obtain voltage V1 between the positive and negative busbar and the voltage Vy1 between Vy1 negative busbar and the ground wire, described Vx1=V1-|Vy1|; The acquisition methods of voltage Vy2 between positive bus-bar among the described step C and the voltage Vx2 between the ground wire and negative busbar and the ground wire is: obtain voltage V2 between the positive and negative busbar and the voltage Vy2 between Vy2 negative busbar and the ground wire, described Vx2=V2-|Vy2|.
The beneficial effects of the utility model: the dc bus insulating resistor detecting circuit that a kind of low energy consumption is provided, disconnecting K during detection disconnects the upper and lower bridge arm of balance bridge, actuating switch K3, make between the upper brachium pontis access positive bus-bar and ground wire of non-equilibrium bridge, make between the lower brachium pontis access negative busbar and ground wire of non-equilibrium bridge, obtain voltage Vx1 between this moment positive bus-bar and ground wire and the voltage Vy1 between negative busbar and the ground wire, set up the equation that only comprises two unknown quantitys---the insulation resistance Rx between bus and the ground wire and the voltage insulation resistance R y between negative busbar and the ground wire---according to these two magnitudes of voltage; Then with the K switch conducting, with K switch 3 cut-offs, obtain voltage Vx2 between this moment positive bus-bar and ground wire and the voltage Vy2 between negative busbar and the ground wire, set up second according to these two magnitudes of voltage and only comprise insulation resistance Rx between bus and the ground wire and the equation of two unknown quantitys of voltage insulation resistance R y between negative busbar and the ground wire, and because access resistance is different, two equation non-equivalences, so far can get unknown quantity Rx and Ry according to two solution of equations that only comprise the non-equivalence of insulation resistance Rx between bus and the ground wire and two unknown quantitys of voltage insulation resistance R y between negative busbar and the ground wire, realize detecting the purpose of insulation resistance, and because in testing process, only in upper brachium pontis and the lower brachium pontis conducting of carrying out making when balance bridge detects balance bridge, therefore balance bridge is only carrying out having electric current to pass through when balance bridge detects in testing process, equal no current in other times, do not produce power consumption, thereby reduced the overall power consumption of system.
Description of drawings
Fig. 1 is the circuit theory diagrams of a kind of low energy consumption dc bus of the utility model insulating resistor detecting circuit.
The process flow diagram of a kind of low energy consumption dc bus of Fig. 2 the utility model insulation resistance detection method.
Embodiment
With the following Examples the utility model is further described.
Embodiment 1
A kind of low energy consumption dc bus of the utility model insulating resistor detecting circuit is one of embodiment of detection method, as shown in Figure 1, the positive bus-bar BUS+ and the negative busbar BUS-that comprise dc bus to be detected, and ground wire PE, be connected with the upper brachium pontis that series resistor R0 and K switch 1 successively forms balance bridge 1 between described positive bus-bar BUS+ and the ground wire PE, be connected with the lower brachium pontis that series resistor R1 and K switch 2 successively forms balance bridges 1 between described negative busbar BUS-and the ground wire PE, wherein R1 resistance value and R0 equate.Also be in series with successively resistance R 2 and the non-equilibrium bridge 2 of resistance R 3 formation between described positive bus-bar BUS+ and the negative busbar BUS-, the voltage non-zero points of described non-equilibrium bridge 2 (tie points that power taking resistance R2 is connected with resistance R in the present embodiment) is connected with ground wire PE by K switch 3.Wherein K switch 1, K2, K3 are photoelectric relay, control its conducting/disconnection by control module.The equivalent resistance of voltage sampling circuit 3 between positive bus-bar BUS+ and ground wire PE is R4, and the equivalent resistance between negative busbar and electric wire is R5, for the ease of calculating, in the present embodiment the resistance value of equivalent resistance R5 is adjusted to equivalent resistance R4 and equates.Certainly the resistance value of equivalent resistance R5 also can be not equal to equivalent resistance R4, only need get final product by adjustment formula when calculating.
In addition, the resistance value of resistance R 2 and R3 is according to formula
Select, wherein Δ u is voltage fluctuation tolerance interval value, and V is the magnitude of voltage between the positive and negative busbar.The voltage of positive and negative busbar all can produce larger fluctuation because of the instantaneous change of circuitous resistance when the non-equilibrium bridge 2 of access, if the senior general of fluctuating undermines circuit even power supply, therefore just this voltage fluctuation Δ u is controlled in the acceptable value range.Again because
,
, wherein the magnitude of voltage V between the positive and negative busbar and resistance R 4 are constant, therefore as long as suitable regulating resistance R2 and the resistance of resistance R 3 can be regulated that voltage fluctuation Δ u is in the tolerance interval value, thereby be avoided excessive voltage fluctuation to undermine circuit.
In conjunction with above circuit, the detection method of the present embodiment as shown in Figure 2, step is as follows:
Steps A: control module gauge tap K1, K switch 2, K switch 3 disconnect, obtain voltage Vx between this moment positive bus-bar and ground wire and the voltage Vy between negative busbar and the ground wire, judge whether Vx or Vy have one to be zero, if, then report to the police and stop to detect, if not, then preserve Vx and/or Vy data;
The fundamental purpose of this step is to judge whether positive bus-bar or negative busbar exist the situation to earth short, and obviously working as can be known Vx from circuit is zero, can judge the positive bus-bar shorted to earth, and control circuit should be reported to the police immediately and be notified host computer at this moment.The negative busbar shorted to earth in like manner can get.Simultaneously, then the method for voltage Vx between positive bus-bar and the ground wire and the voltage Vy between negative busbar and the ground wire of obtaining in this step calculates the Vx value according to Vx=V-|Vy| for by the voltage V between voltage sampling circuit 3 sampling positive bus-bars and the negative busbar and the voltage Vy between negative busbar and the ground wire.This is external to obtain in the process of data by Vx and the Vy of repeatedly sampling, and then calculating mean value improves data accuracy as net result.
Step B: control module Closing Switch K3, cut-off switch K1 and K switch 2, obtain voltage Vx1 between this moment positive bus-bar and ground wire and the voltage Vy1 between negative busbar and the ground wire, judge whether Vx1=Vx or Vy1=Vy, if, then report to the police and stop to detect, if not, then preserve Vx1 and Vy1 data;
This step mainly is to carry out non-equilibrium bridge to detect, namely the resistance value between positive bus-bar and the ground wire access simultaneously the unequal resistance of resistance and obtain positive bus-bar and ground wire between voltage Vx1 and the voltage Vy1 between negative busbar and the ground wire, in conjunction with Fig. 1, have according to Kirchhoff's law this moment
Compare to judge whether normally ground connection of ground wire according to the data of non-equilibrium detection and the data of steps A simultaneously: owing to the resistance R 3 of the resistance R 2 that goes up brachium pontis in the non-equilibrium bridge 2 and lower brachium pontis is unequal, therefore all will inevitably change at the voltage Vx between positive bus-bar and the ground wire and the voltage Vy between negative busbar and the ground wire behind the Closing Switch K3, be Vx1 ≠ Vx and Vy1 ≠ Vy, can judge accordingly whether normally ground connection of ground wire.
Step C: control module Closing Switch K1 and K switch 2, cut-off switch K3 obtains voltage Vx2 between this moment positive bus-bar and ground wire and the voltage Vy2 between negative busbar and the ground wire, preserves Vx2 and Vy2 data;
This step mainly is to carry out balance bridge to detect, namely access simultaneously the resistance that resistance equates and obtain respectively voltage Vx2 between positive bus-bar and the ground wire and the voltage Vy2 between negative busbar and the ground wire in positive bus-bar and resistance value between the ground wire, in conjunction with Fig. 1, have according to Kirchhoff's law this moment
Step D with B step and C step sample voltage value substitution formula (1) and formula (2), calculates Rx, Ry.
This step is namely utilized Vx1, Vy1, Vx2, Vy2, R0, the insulation resistance Rx between R2, R3, R4 calculating positive bus-bar and the ground wire and the voltage insulation resistance R y between negative busbar and the ground wire.Because in step B:
At step C:
Get final product to get formula:
(3)
Simultaneous formula (3) and (4) formula get final product:
(1);
Step e: will calculate the positive bus-bar of gained and the insulation resistance Rx between the ground wire and voltage insulation resistance R y and the preset value between negative busbar and the ground wire and compare, if Rx or Ry are less than preset value, then report to the police, if the bus insulation situation is normal, then upload Rx and Ry value to host computer.
Step F: behind the certain interval of time, carry out again a next cycle detection.
Detect the insulation against ground resistance of positive bus-bar and negative busbar by this circuit and method, in testing process, only when carrying out the balance bridge detection, make upper brachium pontis and the lower brachium pontis conducting of balance bridge 1, therefore balance bridge 1 only has electric current to pass through when balance bridge detects in testing process, equal no current in other times, do not produce power consumption, thereby reduced the overall power consumption of system.Detect before this external detection positive and negative busbar to ground wire whether short circuit and ground wire whether ground connection is normal, Effective Raise the reliability that detects of system.
A kind of low energy consumption dc bus of the utility model insulating resistor detecting circuit be detection method embodiment two, the main technical schemes of the present embodiment is identical with embodiment 1, unaccounted feature adopts the explanation among the embodiment 1 in the present embodiment, no longer gives unnecessary details at this.The difference of the present embodiment and embodiment 1 is, described non-equilibrium bridge comprises K switch 4 and the resistance R 2 that is series at successively between positive bus-bar and the ground wire, be series at successively K switch 5 and resistance R 3 between negative busbar and the ground wire, while actuating switch K4 and K switch 5 get final product when carrying out non-equilibrium bridge detection, while cut-off switch K4 and K switch 5 when balance bridge detects realize voltage non-zero points and the conducting between the ground wire of non-equilibrium bridge and disconnect the K3 that namely adopts K switch 4 and K switch 5 to replace among the embodiment 1 with this.
Should be noted that at last; above embodiment is only in order to illustrate the technical solution of the utility model; but not to the restriction of the utility model protection domain; although with reference to preferred embodiment the utility model has been done to explain; those of ordinary skill in the art is to be understood that; can make amendment or be equal to replacement the technical solution of the utility model, and not break away from essence and the scope of technical solutions of the utility model.
Claims (5)
1. low energy consumption dc bus insulating resistor detecting circuit, comprise balance bridge, non-equilibrium bridge and for detection of the voltage sampling circuit of magnitude of voltage between positive and negative busbar and the ground wire, the upper brachium pontis of described balance bridge and the upper brachium pontis of non-equilibrium bridge are arranged in parallel between the positive bus-bar and ground wire of circuit to be checked, the lower brachium pontis of described balance bridge and the lower brachium pontis of non-equilibrium bridge are arranged in parallel between the negative busbar and ground wire of circuit to be checked, it is characterized in that: also comprise the voltage non-zero points of controlling non-equilibrium bridge and the K switch 3 of ground conductive/disconnection, also comprise the K switch of the upper brachium pontis of controlling balance bridge and the simultaneously conducting of lower brachium pontis/disconnect simultaneously.
2. a kind of low energy consumption dc bus insulating resistor detecting circuit as claimed in claim 1, it is characterized in that: the upper brachium pontis of described balance bridge comprises the resistance R 0 that is serially connected with between positive bus-bar and the ground wire, the lower brachium pontis of described balance bridge comprises the resistance R 1 that equates with resistance R 0 resistance that is serially connected with between negative busbar and the ground wire, and described K switch comprises the K switch 1 of connecting with R0 and the K switch 2 of connecting with R1.
3. a kind of low energy consumption dc bus insulating resistor detecting circuit as claimed in claim 1, it is characterized in that: the upper brachium pontis of described non-equilibrium bridge comprises resistance R 2, lower brachium pontis comprises resistance R 3, between resistance R 2 and resistance R 3 series connection and positive bus-bar and the negative busbar, the tie point of described resistance R 2 and R3 is as the voltage non-zero points.
4. a kind of low energy consumption dc bus insulating resistor detecting circuit as claimed in claim 1, it is characterized in that: described voltage sampling circuit comprises the detection resistance R 4 that is connected between positive bus-bar and the ground wire, and is connected to the detection resistance R 5 that equates with resistance R 4 resistances between negative busbar and the ground wire.
5. a kind of low energy consumption dc bus insulating resistor detecting circuit as claimed in claim 4, it is characterized in that: described non-equilibrium bridge comprises resistance R 2 and the resistance R 3 that is serially connected with between the positive and negative busbar, described resistance R 2 is connected tie point and is connected with ground wire by K switch 3 with R3, the resistance value of described resistance R 2 and resistance R 3 satisfies formula
, wherein Δ u is voltage fluctuation tolerance interval value, V is the magnitude of voltage between the positive and negative busbar.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 201220562588 CN202870174U (en) | 2012-10-30 | 2012-10-30 | Low energy consumption circuit for detecting insulating resistance of DC bus |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 201220562588 CN202870174U (en) | 2012-10-30 | 2012-10-30 | Low energy consumption circuit for detecting insulating resistance of DC bus |
Publications (1)
Publication Number | Publication Date |
---|---|
CN202870174U true CN202870174U (en) | 2013-04-10 |
Family
ID=48036883
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN 201220562588 Withdrawn - After Issue CN202870174U (en) | 2012-10-30 | 2012-10-30 | Low energy consumption circuit for detecting insulating resistance of DC bus |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN202870174U (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102998537A (en) * | 2012-10-30 | 2013-03-27 | 广东易事特电源股份有限公司 | Low-energy-consumption detection circuit and low-energy-consumption detection method for direct-current bus insulation resistance |
CN105738752A (en) * | 2016-04-20 | 2016-07-06 | 云南云铝涌鑫铝业有限公司 | Grounding detection apparatus and detection method for electrolytic DC system |
CN107450001A (en) * | 2017-07-14 | 2017-12-08 | 武汉合康智能电气有限公司 | A kind of high-voltage isulation detecting system of zero disturbance |
CN114002502A (en) * | 2020-07-27 | 2022-02-01 | 宁德时代新能源科技股份有限公司 | Insulation resistance detection circuit and method |
-
2012
- 2012-10-30 CN CN 201220562588 patent/CN202870174U/en not_active Withdrawn - After Issue
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102998537A (en) * | 2012-10-30 | 2013-03-27 | 广东易事特电源股份有限公司 | Low-energy-consumption detection circuit and low-energy-consumption detection method for direct-current bus insulation resistance |
CN102998537B (en) * | 2012-10-30 | 2015-09-09 | 广东易事特电源股份有限公司 | A kind of DC bus insulating resistor detecting circuit of low energy consumption and detection method |
CN105738752A (en) * | 2016-04-20 | 2016-07-06 | 云南云铝涌鑫铝业有限公司 | Grounding detection apparatus and detection method for electrolytic DC system |
CN105738752B (en) * | 2016-04-20 | 2019-04-30 | 云南云铝涌鑫铝业有限公司 | Electrolysis direct current system ground detection device and detection method |
CN107450001A (en) * | 2017-07-14 | 2017-12-08 | 武汉合康智能电气有限公司 | A kind of high-voltage isulation detecting system of zero disturbance |
CN114002502A (en) * | 2020-07-27 | 2022-02-01 | 宁德时代新能源科技股份有限公司 | Insulation resistance detection circuit and method |
WO2022022038A1 (en) * | 2020-07-27 | 2022-02-03 | 宁德时代新能源科技股份有限公司 | Insulation resistance detection circuit and method |
CN114002502B (en) * | 2020-07-27 | 2023-01-13 | 宁德时代新能源科技股份有限公司 | Insulation resistance detection circuit and method |
US11733279B2 (en) | 2020-07-27 | 2023-08-22 | Contemporary Amperex Technology Co., Limited | Circuit and method for detecting insulation resistance |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN102998537B (en) | A kind of DC bus insulating resistor detecting circuit of low energy consumption and detection method | |
CN104535839B (en) | Photovoltaic grid-connected inverter insulation resistance detecting method and detecting device for implementing same | |
CN103869179B (en) | A kind of insulated monitoring method of straight-flow system | |
CN202870174U (en) | Low energy consumption circuit for detecting insulating resistance of DC bus | |
CN105548719B (en) | A kind of detection circuit and method of insulation against ground resistance | |
CN206020596U (en) | A kind of charging pile insulation monitoring and warning device of bridge method design | |
CN103558506B (en) | Non-implanted formula DC system earth fault lookup method and device thereof | |
CN205263278U (en) | Monomer internal resistance of battery and connecting wire resistance measurement device thereof | |
CN103675705A (en) | Method for redundancy check of currents of power battery | |
CN202649380U (en) | Digital cable insulation fault automatic locator | |
CN103176049A (en) | Circuit, device and method used for ground insulation monitoring of earth-free DC (Direct Current) system | |
CN105425155A (en) | High-voltage battery pack total voltage and insulation resistance detection circuit and detection method | |
CN105182137B (en) | Method and apparatus for diagnosing a fault of an electric anti-icing heating unit | |
WO2013106985A1 (en) | Method for identifying fault direction without voltage measurement information and directional element thereof | |
CN107834978B (en) | Photovoltaic array earth insulation resistance detection circuit, device and non-isolated photovoltaic inverter | |
CN202166682U (en) | Fault detecting device of direct grounding | |
CN103683188A (en) | Safety detection apparatus of solar energy inverter | |
CN105717426A (en) | Insulation monitoring device and method capable of preventing buses from misoperation | |
CN202929116U (en) | Battery tester | |
CN207853843U (en) | Photovoltaic array ground insulation impedance detection circuit and device and non-isolated photovoltaic inverter | |
CN104502778A (en) | Detecting device for alternating current entering of direct current system and realizing method of detecting device | |
CN105486930B (en) | With silicon chain direct current system bus to the detection device and method of ground resistance | |
CN102998536B (en) | A kind of DC bus insulation resistance detection method of high reliability | |
CN107607839A (en) | Single armed unbalanced bridge insulation monitoring and warning device | |
CN103900777A (en) | Strut type electronic current transformer one-time vibration detecting device and method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
AV01 | Patent right actively abandoned |
Granted publication date: 20130410 Effective date of abandoning: 20150909 |
|
RGAV | Abandon patent right to avoid regrant |