CN203673005U - Direct current insulation monitor - Google Patents

Direct current insulation monitor Download PDF

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Publication number
CN203673005U
CN203673005U CN201320765710.4U CN201320765710U CN203673005U CN 203673005 U CN203673005 U CN 203673005U CN 201320765710 U CN201320765710 U CN 201320765710U CN 203673005 U CN203673005 U CN 203673005U
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resistance
switch
circuit
ground
bridge
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刘兴华
蒋中为
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SHENZHEN GOLD POWER TECHNOLOGY Co Ltd
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SHENZHEN GOLD POWER TECHNOLOGY Co Ltd
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Abstract

The utility model provides a direct current insulation monitor for monitoring circuit anode insulation against ground and circuit cathode insulation against ground. The direct current insulation monitor includes unbalanced bridges for detecting a major loop, a current sensor for detecting a current of the unbalanced bridge, a voltage measuring circuit for measuring an anode voltage to ground and a cathode voltage to ground of the circuit being monitored, and a one-chip computer for processing outputs of the current sensor and a voltage measuring circuit. The unbalanced bridges are three-level unbalanced bridges controlled by the one-chip computer. The advantages of the direct current insulation monitor are that the range of the ground resistance value of a detecting branch loop is wider, since a bus is accessed by utilizing the switching of the three-level unbalanced bridges, the structure is simple, and the manufacture cost is low.

Description

A kind of DC insulation monitoring instrument
Technical field
The utility model relates to circuit insulation against ground status monitoring field, particularly a kind of device of suspension high voltage DC bus and its point of branch road insulation against ground situation over the ground of measuring in real time online.
Background technology
At present, solar photovoltaic grid-connection system, direct-current remote feeding power system, HVDC high-voltage direct current, all adopt the DC system suspending over the ground to set up and make; In the time there is ground connection in circuit, may affect the operation of straight-flow system and cause physical electrical shock fire protection, if can not find rapidly earth fault reparation, may cause the generation of significant trouble.So it is very necessary and important that the detection of power-supply system state of insulation and management become.
The method of existing detection mainly contains principle of balance bridge and low-frequency acquisition principle.Principle of balance bridge can not detection system positive and negative electrode insulation is equal while declining situation; And most list group electric bridges that use, only be applicable to narrower interval voltage measurement and power supply, may use the electric bridge of less resistance in order to measure larger stake resistance, and be connected on all the time and on bus, become load, increase power consumption, in the time that input voltage is higher, reduced detectability and precision to little impedance earth resistance.
Use nonequilibrium bridge can detection system both positive and negative polarity insulation is equal while declining situation, but majority also only uses single group electric bridge, between measuring voltage and resistance area, there is no improvement, the electric bridge of less resistance also can increase power consumption, cause Bus Voltage larger fluctuation in the time that high pressure switches.
As shown in Figure 1, for using nonequilibrium bridge to carry out ground connection resistance measuring principle figure, switching resistance mode and algorithm while demonstrating in the embodiment shown in fig. 1 bus insulation against ground resistance measurement:
The 1st step: in the time that closed ground of S1 S2 disconnects, the voltage recording on RX and RY is respectively Ux1, Uy1, can obtain according to Ohm law:
Ux 1 ( Ra 1 ∪ Rx ) = Uy 1 Ry Transplant: Ry = Uy 1 Ux 1 × ( Ra 1 ∪ Rx ) (formula 1)
The 2nd step: in the time that S1 disconnects S2 closure, the voltage recording on RX and RY is respectively Ux2, and Uy2 can obtain:
Ux 2 Rx = Uy 2 ( Ra 2 ∪ Ry ) Transplant: Rx = Ux 2 Uy 2 × ( Ra 2 ∪ Ry ) (formula 2)
Simultaneous (formula 1) can solve bus both positive and negative polarity insulation against ground resistance R x and Ry with (formula 2) composition linear equation in two unknowns group.
Switching resistance mode and algorithm while demonstrating in the embodiment shown in fig. 1 branch road insulation against ground resistance measurement: in the time of the no ground resistance R X of positive and negative busbar or RY, load current flows to HM-by HM+, opposite sign but equal magnitude, balance mutually, SCD is output as 0, in the time having stake resistance RX or RY, balance is destroyed, and SCD will detect by non-equilibrium (leakage) electric current between HM+ or HM-and ground; In the 1st step: in the time that the closed S2 of S1 disconnects, the voltage recording on RX and RY is respectively Ux1, Uy1, leakage current is I1, equivalent electrical circuit as shown in Figure 2, can obtain:
I 1 = Ux 1 Rx - Uy 1 Ry (formula 3)
The 2nd step: in the time that S1 disconnects S2 closure, the voltage recording on RX and RY is respectively Ux2, Uy2, leakage current is I2, equivalent electrical circuit as shown in Figure 3, can obtain:
I 2 = Ux 2 Rx - Uy 2 Ry (formula 4)
Simultaneous (formula 3) can be separated out branch both positive and negative polarity insulation against ground resistance R x and Ry with (formula 4) composition linear equation in two unknowns group.
Detect stake resistance by low-frequency acquisition principle and be subject to the straight-flow system restriction of distributed capacitance over the ground, and low-frequency ac signal is easily subject to extraneous interference, the low-frequency ac signal injecting in addition increases the ripple coefficient of voltage of straight-flow system, and system buildup is more complicated and huge.
Some functions of the equipments is single, can only local management and cannot telemanagement without communication interface; Have have communication interface but traffic rate can not be arranged voluntarily by user, underaction.
Utility model content
In order to overcome existing deficiency, the utility model provides a kind of DC insulation monitoring instrument device, support DC420V high input voltage, support AC and DC power supply input, when detection, electric bridge switching is accessed bus by ability simultaneously, situation when energy detection system bus and the equal decline of each branch road positive and negative electrode insulation, the different resistance electric bridges of switching flexibly, widen between measuring voltage and resistance area, simple in structure, take up room little.And can detect positive and negative busbar voltage-to-ground, and distinguish positive and negative busbar and the independent insulation against ground resistance value of branch road.Alarm resistance also can be set, send light alarm during lower than the set alarm resistance of user when insulativity, with the RS485 communication interface of isolation, and traffic rate can arrange, can use communication mode the parameters of equipment is set and reads metrical information, facilitate long-distance remote control, remote measurement.
The utility model for the technical scheme that realizes its technical purpose and adopt is: a kind of DC insulation monitoring instrument, the positive and negative electrode insulation against ground of observation circuit, comprise as the unbalanced bridge that detects major loop, the current sensor that detects described unbalanced bridge electric current, the single-chip microcomputer of measuring the tension measuring circuit of monitored circuit positive and negative electrode voltage-to-ground, the output of current sensor and tension measuring circuit being processed the described unbalanced bridge monolithic processor controlled four groups of described three grades of unbalanced bridges of serving as reasons;
Four groups of described three grades of unbalanced bridges comprise:
The resistance bridge A being formed by resistance R a1, resistance R a2, switch S 1, switch S 2, the resistance R a2 of described resistance R a1 utilizes respectively the other end of switch S 1 and switch S 2 ground connection, described resistance R a1, resistance R a2 to connect respectively the positive and negative electrode of monitored circuit; Resistance R a1 equates with resistance R a2 resistance;
The resistance bridge B being formed by resistance R b1, resistance R b2, switch S 3, switch S 4, the resistance R b2 of described resistance R b1 utilizes respectively the other end of switch S 3 and switch S 4 ground connection, described resistance R b1, resistance R b2 to connect respectively the positive and negative electrode of monitored circuit; Resistance R b1 equates with resistance R b2 resistance;
The resistance bridge C that resistance R c1, resistance R c2, resistance R c3 and switch S 5 form; Described resistance R c1, resistance R c2, resistance R c3 contact successively, and described switch S 5 is arranged between resistance R c2 and resistance R c3 junction and ground, and the other end of resistance R c1 and resistance R c3 connects respectively the positive and negative electrode of monitored circuit;
The resistance bridge D being formed by resistance R d1, resistance R d2, resistance R d3 switch S 6; Described resistance R d1, resistance R d2, resistance R d3 contact successively, and described switch S 6 is arranged between resistance R d1 and resistance R d2 junction and ground, and the other end of resistance R d1 and resistance R d3 connects respectively the positive and negative electrode of monitored circuit;
Resistance R c1, resistance R c2 and resistance R c3 and resistance R d1, resistance R d2 and resistance R d3 resistance equate;
Described switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 are respectively by described Single-chip Controlling.Described switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 is respectively light isolation metal-oxide-semiconductor.
Further, in above-mentioned DC insulation monitoring instrument: described tension measuring circuit comprises the anodal voltage-to-ground metering circuit of circuit-under-test and circuit-under-test negative pole voltage-to-ground metering circuit;
Described anodal voltage-to-ground metering circuit comprises the first bleeder circuit that anodal voltage-to-ground is reduced in proportion to measurement range ability, the voltage signal of the first described bleeder circuit output is linked into the emitter follower U1A of described single-chip microcomputer;
Described negative pole voltage-to-ground metering circuit comprises the second bleeder circuit that negative pole voltage-to-ground is reduced in proportion to measurement range ability, the voltage signal of the second described bleeder circuit output is linked into the anti-amplifier U1B of the 1:1 of described single-chip microcomputer.
Further, in above-mentioned DC insulation monitoring instrument: described current sensor, tension measuring circuit output to single-chip microcomputer time also comprise selection input detecting circuit; Described selection input detecting circuit comprises multiselect 1 analog switch, 1:1 sign-changing amplifier U2A, emitter follower U2B;
Multiselect 1 analog switch output connects the out-phase end of 1:1 sign-changing amplifier U2A by resistance R 16, the in-phase end of 1:1 sign-changing amplifier U2A is by resistance R 129 ground connection; Between the out-phase end of 1:1 sign-changing amplifier U2A and in-phase end, meet diode D15, the anode of diode D15 connects the out-phase end of 1:1 sign-changing amplifier U2A, and the output of 1:1 sign-changing amplifier U2A connects the negative signal input end of described single-chip microcomputer;
Multiselect 1 analog switch output meets emitter follower U2B input end by resistance R 36, also passes through diode D20 ground connection, the plus earth of diode D20 at the input end of emitter follower U2B.
Further, in above-mentioned DC insulation monitoring instrument: the positive and negative electrode of described circuit-under-test is respectively positive electrode bus and the negative pole bus of system under test (SUT).
Further, in above-mentioned DC insulation monitoring instrument: also comprise reverse-connection preventing circuit, described reverse-connection preventing circuit comprises diode D22 and diode D14, and the negative electrode of described diode D22 is connected with the negative pole bus of system under test (SUT), and anode connects the cathode voltage metering circuit of described electric bridge; The anode of described diode D14 connects the positive electrode bus of system under test (SUT), and negative electrode connects the cathode voltage metering circuit of described electric bridge.
The beneficial effects of the utility model are that, owing to using three grades of unbalanced bridge switching mode access buses, detection branch grounding resistance scope is wider; Simple in structure, cost is low.
Below with reference to drawings and Examples, the utility model is described in detail.
Accompanying drawing explanation
Fig. 1 is grid grounding impedance measurement principle of simulation figure.
Fig. 2 is the utility model system function module composition frame chart.
Fig. 3 is three grades of unbalance bridge circuit schematic diagrams that use in the utility model.
Fig. 4 is the anodal voltage-to-ground metering circuit schematic diagram using in the utility model.
Fig. 5 is the negative pole voltage-to-ground metering circuit schematic diagram using in the utility model.
Fig. 6 uses reverse-connection preventing circuit schematic diagram in the utility model.
Fig. 7 is the selection input detecting circuit schematic diagram using in the utility model.
Embodiment
Embodiment 1, as shown in Figure 2, in the present embodiment, the power supply that DC insulation monitoring instrument adopts is isolation type switch power, output is for the various voltages of sensor, single-chip microcomputer, RS485 and testing circuit respectively.Detect major loop and use up the variation of four groups of three grades of unbalanced bridges detection busbar voltages of isolation MOS switching, carry out detection branch out-of-balance current by DC current sensor, use resistance to connect busbar voltage proportion divider, use single-chip microcomputer and automatic program control light isolation MOS, when detection, just electric bridge is accessed to bus, first use large impedance bridge to detect bus line longitudinal balance, re-use middle impedance electric bridge and detect the total resistance to earth of bus, if find, insulation resistance value is large, the little impedance bridge of the less switching of leakage current, improves measuring accuracy to increase grounding leakage current; Use 8 to select 1 analog switch to select the input of branch sensor signal, use AD changing voltage, current analog amount, then calculate the insulation resistance of bus and branch road; Use special isolation RS 485 chip to be connected with the TTL232 serial port of single-chip microcomputer, communicate by letter with host computer by agreement, exchange is measured and data is set.Use green LED lamp indication running status; Use red LED lamp indication alarm status.
As shown in Figure 3: in the present embodiment, demonstrate bus line longitudinal balance measuring principle: three grades of unbalance bridge circuits that use in the present embodiment, wherein:
The resistance bridge A being formed by resistance R a1, resistance R a2, switch S 1, switch S 2, the resistance R a2 of resistance R a1 utilizes respectively the other end of switch S 1 and switch S 2 ground connection, resistance R a1, resistance R a2 to connect respectively positive electrode bus and the negative pole bus of monitored system under test (SUT); Resistance R a1 equates with resistance R a2 resistance.
The resistance bridge B being formed by resistance R b1, resistance R b2, switch S 3, switch S 4, the resistance R b2 of resistance R b1 utilizes respectively the other end of switch S 3 and switch S 4 ground connection, resistance R b1, resistance R b2 to connect respectively positive electrode bus and the negative pole bus of monitored system under test (SUT); Resistance R b1 equates with resistance R b2 resistance.
The resistance bridge C that resistance R c1, resistance R c2, resistance R c3 and switch S 5 form; Resistance R c1, resistance R c2, resistance R c3 contact successively, and switch S 5 is arranged between resistance R c2 and resistance R c3 junction and ground, and the other end of resistance R c1 and resistance R c3 connects respectively positive electrode bus and the negative pole bus of monitored system under test (SUT).
The resistance bridge D being formed by resistance R d1, resistance R d2, resistance R d3 switch S 6; Described resistance R d1, resistance R d2, resistance R d3 contact successively, and switch S 6 is arranged between resistance R d1 and resistance R d2 junction and ground, and the other end of resistance R d1 and resistance R d3 connects respectively positive electrode bus and the negative pole bus of monitored system under test (SUT).
Resistance R c1, resistance R c2 and resistance R c3 and resistance R d1, resistance R d2 and resistance R d3 resistance equate above.
In actual application, above resistance R a1, Ra2, Rb1, Rb2, Rc1, Rc2, Rc3, Rd1, Rd2, Rd3 also can represent the simplification of one or more resistance series/parallel set.
Switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 are respectively by Single-chip Controlling.In the present embodiment, switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 are respectively light isolation metal-oxide-semiconductor.
Resistance bridge A and resistance bridge B adopt the lower resistance composition of impedance, in the time switching, easily cause the upheaval that Bus Voltage is larger, again due to the existence of distributed capacitance, while needing wait longer, just can stablize after switching.So be not suitable for frequent switching.Therefore introduce high-resistance unbalanced resistance bridge C and resistance bridge D, be specifically designed to and detect bus balanced to ground, in the time imbalance being detected, just use resistance bridge A and resistance bridge B to carry out switching; So can faster response, reduce the upheaval of Bus Voltage.Embodiment is: resistance bridge C and resistance bridge D are connected to when flat between the positive electrode bus HM+ and negative pole bus HM-of system under test (SUT), switch S 5, and S6 disconnects; The voltage (positive and negative busbar voltage-to-ground) that when measurement, then first Closing Switch S5 measures on RX and RY is respectively Ux1, and then Uy1 disconnects after S5 closed S6 again, and the voltage recording on RX and RY is respectively Ux2, and Uy2 finally disconnects S6; In the time of the good no ground resistance R X of insulation against ground and RY, due to Rc1=Rc2=Rc3=Rd1=Rd2=Rd3, there is Ux1=Uy2, Uy1=Ux2, while access respectively or simultaneously, all will break this balance in the time having stake resistance RX or RY, in the time imbalance being detected, just forward A/B bridge switching to and carry out impedance measurement and calculating.
In the time that positive and negative busbar insulation against ground is good, not switching A/B electric bridge, not detection branch leakage current, reduces the vibration of Bus Voltage, has reduced Overall Power Consumption, increases the service life.
When actual enforcement, first use larger impedance resistance bridge A to detect the total resistance to earth of bus, if find, insulation resistance value is large, the less less impedance resistance bridge of the switching B that changes of leakage current, to increase grounding leakage current, if find, leakage current is still less, resistance bridge A is synchronizeed to switching in parallel with resistance bridge B, to increase grounding leakage current, this is very practical in the time that voltage is larger compared with low and stake resistance, so can widen measurement range and improve measuring accuracy.
Being to use reverse-connection preventing circuit schematic diagram in the present embodiment shown in Fig. 6, J13 is for detecting bus input interface, the positive electrode bus that pin 3 is system under test (SUT), the negative pole bus that pin 1 is system under test (SUT), D14 forward is concatenated in input positive electrode bus, negative electrode meets the HM+ of internal measurement circuit, D22 is oppositely concatenated on negative pole bus, and anode meets the HM-of internal measurement circuit, forms input reverse-connection preventing circuit; Because detected bus is direct current, have positive-negative polarity, if connect anti-by likely by the device failure of device interior, so add reverse-connection preventing circuit protected.In the time of input reverse polarity connection, due to unilateral conduction D22, the not conducting of D14 of diode, the internal electrical loop no current of receiving HM-/HM+ passes through, thereby plays a protective role.As shown in Figure 4 and Figure 5, resistance pressure-dividing network circuit, for the high pressure of input detection line is divided into low pressure through many resistance serial connections, detects for the AD modular converter of MCU, thereby in dividing potential drop ratio reduction input voltage.Wherein R1, R3, R5, R8, R9, R93, R96 is composed in series positive bus-bar dividing potential drop over the ground, and the partial pressure value of getting on R9+R96 is done measurement component, is transported to the operational amplifier in emitter follower U1A; R2, R6, R7, R10, R61, R107, R124 is composed in series negative busbar dividing potential drop over the ground, and the partial pressure value of getting on R10+R107 is done measurement component, is transported to the operational amplifier in 1:1 inverting amplifier U1B; Negative input voltage reversal is output into positive voltage by emitter follower U1A and 1:1 inverting amplifier U1B, is input to the AD conversion I/O mouth of MCU; Diode D1~D4, for clamper amplifier output voltage, protects MCU port.
Figure 7 shows that the selection input detecting circuit schematic diagram in the present embodiment, U13 8 selects 1 module switch, SIG1~SIG8 is used for connecting 8 branch road leakage current sensor output signals, 4051-A/B/C be the channel selecting signal of MCU programmed control U13 for selecting it 1 to pass through, signal is delivered to respectively to amplifier U2A and U2B.Amplifier U2A is connected into 1:1 inverting amplifier, is responsible for only negative signal being converted to positive signal, then exports to MCU and detects; The effect of D15 is short circuit positive signal, makes U2A only process negative signal; Amplifier U2B is connected into emitter follower pattern, is responsible for that positive signal is in statu quo exported to MCU and detects; The effect of D20 is short circuit negative signal, makes U2B only process positive signal.
In addition, in the present embodiment, MCU(is single-chip microcomputer) inside contains AD modular converter, 232 serial communication modulars, be responsible for controlling resistance bridge gauge rule switching, the detection of positive and negative busbar voltage-to-ground, the signal quantization of branch road leakage current sensor, insulation resistance calculating, 485 protocol communications, parameter arrange preservation, according to operation and the light on and off of alarm status control pilot lamp.

Claims (6)

1. a DC insulation monitoring instrument, the positive and negative electrode insulation against ground of observation circuit, comprise as the unbalanced bridge that detects major loop, the current sensor that detects described unbalanced bridge electric current, the single-chip microcomputer of measuring the tension measuring circuit of monitored circuit positive and negative electrode voltage-to-ground, the output of current sensor and tension measuring circuit being processed, it is characterized in that: the described unbalanced bridge described monolithic processor controlled three grades of unbalanced bridges of serving as reasons;
Three grades of described unbalanced bridges comprise:
The resistance bridge A being formed by resistance R a1, resistance R a2, switch S 1, switch S 2, the resistance R a2 of described resistance R a1 utilizes respectively the other end of switch S 1 and switch S 2 ground connection, described resistance R a1, resistance R a2 to connect respectively the positive and negative electrode of monitored circuit; Resistance R a1 equates with resistance R a2 resistance;
The resistance bridge B being formed by resistance R b1, resistance R b2, switch S 3, switch S 4, the resistance R b2 of described resistance R b1 utilizes respectively the other end of switch S 3 and switch S 4 ground connection, described resistance R b1, resistance R b2 to connect respectively the positive and negative electrode of monitored circuit; Resistance R b1 equates with resistance R b2 resistance;
The resistance bridge C that resistance R c1, resistance R c2, resistance R c3 and switch S 5 form; Described resistance R c1, resistance R c2, resistance R c3 contact successively, and described switch S 5 is arranged between resistance R c2 and resistance R c3 junction and ground, and the other end of resistance R c1 and resistance R c3 connects respectively the positive and negative electrode of monitored circuit;
The resistance bridge D being formed by resistance R d1, resistance R d2, resistance R d3 switch S 6; Described resistance R d1, resistance R d2, resistance R d3 contact successively, and described switch S 6 is arranged between resistance R d1 and resistance R d2 junction and ground, and the other end of resistance R d1 and resistance R d3 connects respectively the positive and negative electrode of monitored circuit;
Resistance R c1, resistance R c2 and resistance R c3 and resistance R d1, resistance R d2 and resistance R d3 resistance equate;
Described switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 are respectively by described Single-chip Controlling.
2. DC insulation monitoring instrument according to claim 1, is characterized in that: described switch S 1, switch S 2, switch S 3, switch S 4, switch S 5 and switch S 6 is respectively light isolation metal-oxide-semiconductor.
3. DC insulation monitoring instrument according to claim 1, is characterized in that: described tension measuring circuit comprises the anodal voltage-to-ground metering circuit of circuit-under-test and circuit-under-test negative pole voltage-to-ground metering circuit;
Described anodal voltage-to-ground metering circuit comprises the first bleeder circuit that anodal voltage-to-ground is reduced in proportion to measurement range ability, the voltage signal of the first described bleeder circuit output is linked into the emitter follower U1A of described single-chip microcomputer;
Described negative pole voltage-to-ground metering circuit comprises the second bleeder circuit that negative pole voltage-to-ground is reduced in proportion to measurement range ability, the voltage signal of the second described bleeder circuit output is linked into the anti-amplifier U1B of the 1:1 of described single-chip microcomputer.
4. DC insulation monitoring instrument according to claim 1, is characterized in that: described current sensor, tension measuring circuit output to single-chip microcomputer time also comprise selection input detecting circuit; Described selection input detecting circuit comprises multiselect 1 analog switch, 1:1 sign-changing amplifier U2A, emitter follower U2B;
Multiselect 1 analog switch output connects the out-phase end of 1:1 sign-changing amplifier U2A by resistance R 16, the in-phase end of 1:1 sign-changing amplifier U2A is by resistance R 129 ground connection; Between the out-phase end of 1:1 sign-changing amplifier U2A and in-phase end, meet diode D15, the anode of diode D15 connects the out-phase end of 1:1 sign-changing amplifier U2A, and the output of 1:1 sign-changing amplifier U2A connects the negative signal input end of described single-chip microcomputer;
Multiselect 1 analog switch output meets emitter follower U2B input end by resistance R 36, also passes through diode D20 ground connection, the plus earth of diode D20 at the input end of emitter follower U2B.
5. according to arbitrary described DC insulation monitoring instrument in claim 1 to 4, it is characterized in that: the positive and negative electrode of described circuit-under-test is respectively positive electrode bus and the negative pole bus of system under test (SUT).
6. DC insulation monitoring instrument according to claim 5, it is characterized in that: also comprise reverse-connection preventing circuit, described reverse-connection preventing circuit comprises diode D22 and diode D14, the negative electrode of described diode D22 is connected with the negative pole bus of system under test (SUT), and anode connects negative pole (HM-) tension measuring circuit of described electric bridge; The anode of described diode D14 connects the positive electrode bus of system under test (SUT), and negative electrode connects positive pole (HM+) tension measuring circuit of described electric bridge.
CN201320765710.4U 2013-11-28 2013-11-28 Direct current insulation monitor Active CN203673005U (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105158661A (en) * 2015-09-01 2015-12-16 国网吉林省电力有限公司延边供电公司 Insulation fault positioning monitoring device of direct-current power supply system
CN105606897A (en) * 2015-12-28 2016-05-25 哈密创动科技有限公司 Branch insulating impedance monitoring and PV power generation method, inverter and PV power generation system
CN110082599A (en) * 2019-06-03 2019-08-02 合肥国轩高科动力能源有限公司 A kind of insulating monitoring circuit
CN110691976A (en) * 2017-06-29 2020-01-14 华为技术有限公司 Remote power supply module, direct-current power system and fault detection method of direct-current power system
CN111025176A (en) * 2019-11-21 2020-04-17 国网河南省电力公司商丘供电公司 Portable direct current power supply system loop detection method and device thereof
WO2021043173A1 (en) * 2019-09-06 2021-03-11 中兴通讯股份有限公司 Distributed insulation detection device for multi-stage dc system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105158661A (en) * 2015-09-01 2015-12-16 国网吉林省电力有限公司延边供电公司 Insulation fault positioning monitoring device of direct-current power supply system
CN105606897A (en) * 2015-12-28 2016-05-25 哈密创动科技有限公司 Branch insulating impedance monitoring and PV power generation method, inverter and PV power generation system
CN110691976A (en) * 2017-06-29 2020-01-14 华为技术有限公司 Remote power supply module, direct-current power system and fault detection method of direct-current power system
CN110691976B (en) * 2017-06-29 2021-03-23 华为技术有限公司 Remote power supply module, direct-current power system and fault detection method of direct-current power system
US11374395B2 (en) 2017-06-29 2022-06-28 Huawei Technologies Co., Ltd. Remote power unit, direct current power system and direct current power system fault detection method
CN110082599A (en) * 2019-06-03 2019-08-02 合肥国轩高科动力能源有限公司 A kind of insulating monitoring circuit
WO2021043173A1 (en) * 2019-09-06 2021-03-11 中兴通讯股份有限公司 Distributed insulation detection device for multi-stage dc system
CN111025176A (en) * 2019-11-21 2020-04-17 国网河南省电力公司商丘供电公司 Portable direct current power supply system loop detection method and device thereof

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