Intelligent portable detection method and device for preventing open circuit of storage battery pack

Abstract

The invention belongs to the field of direct-current power supply systems for transformer substations, and particularly relates to an intelligent portable storage battery pack open circuit prevention detection method and device. The method comprises the following steps: judging whether a direct-current system operates normally or not through output voltage of a charger and initial voltage of a direct-current bus, if so, connecting a step-down silicon chain to the direct-current bus in series and connecting a storage battery pack to a direct-current power supply system to enable the storage battery pack to bear a conventional load of the direct-current power supply system, and judging whether the loading capacity of the conventional load of the storage battery is qualified or not; if the loading capacity of the conventional load of the storage battery is qualified, the simulated load is connected to a direct-current power supply system, whether the impact resistance of the storage battery is qualified is judged, if the impact resistance of the storage battery is qualified, the simulated load is disconnected, the voltage reduction silicon chain is in short circuit, the final voltage of the direct-current bus is obtained, and whether the performance of the storage battery pack is qualified is judged; the method can comprehensively check the effectiveness of the storage battery, discover the fault of the storage battery in time, verify whether the system can bear a normal load or not, and ensure the operation safety of the DC system.

Description

Technical Field

[0001] This invention belongs to the field of DC power supply systems for substations, and specifically relates to an intelligent portable method and device for detecting open circuits in battery packs. Background Technology

[0002] Storage batteries are the "heart" of a DC power system and the last line of defense for ensuring the normal operation of electrical equipment. As a DC backup power source, the battery will switch from backup power to primary power to supply power to the DC loads if the charging device loses power or malfunctions and cannot supply power to the DC bus. The reliability of the battery directly affects the operational safety of the substation.

[0003] To prevent DC system accidents, the operation management and maintenance of batteries should be strengthened. Among them, the verification capacity test is the most realistic, objective and reliable means to verify the performance and remaining capacity of batteries. However, this method is labor-intensive, has a long test cycle and a window period, and manual operation has the safety hazards of undercharging, overcharging, short circuit and DC power failure. Summary of the Invention

[0004] To address the safety hazards associated with battery performance and condition monitoring in existing technologies, a smart portable method and device for detecting open circuits in battery packs is proposed.

[0005] A smart portable method for detecting open circuits in battery packs includes:

[0006] Obtain the output voltage of the charger and the initial voltage of the DC power system. Determine whether the DC system is operating normally based on the output voltage of the charger and the initial voltage of the DC bus. If so, connect the step-down silicon chain in series with the DC bus and connect the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system. Determine whether the battery pack's normal load-carrying capacity is qualified based on the DC bus voltage at multiple time points after the battery pack is connected to the DC power system.

[0007] If the battery's normal load carrying capacity is qualified, the simulated load is connected to the DC power system, and the impact resistance of the battery is judged based on the DC bus voltage after the simulated load is connected.

[0008] If the battery's impact resistance is qualified, disconnect the simulated load and short-circuit the step-down silicon chain to obtain the final DC bus voltage. If the final DC bus voltage is higher than the set voltage judgment value, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

[0009] A smart portable battery pack open circuit detection device includes: a charger, a voltage acquisition unit, a step-down silicon chain, a battery pack, a simulated load, and a control unit;

[0010] The positive output terminal of the charger is connected to one end of the positive terminal of the DC bus through the first contact, and the negative output terminal of the charger is connected to one end of the negative terminal of the DC bus. The charger is used to supply power to the DC bus.

[0011] One end of the step-down silicon chain is connected to the positive output terminal of the charger, and the other end of the step-down silicon chain is connected to one end of the positive terminal of the DC bus.

[0012] The positive terminal of the simulated load is connected to the positive terminal of the DC bus through the second contact, and the negative terminal of the simulated load is connected to the negative terminal of the DC bus through the third contact.

[0013] The voltage acquisition unit is used to acquire the output voltage of the DC power system charger and the initial voltage of the DC bus when the first contact is closed, the second contact is open, and the third contact is open, and to transmit the output voltage of the DC power system charger and the initial voltage of the DC bus to the control unit.

[0014] The control unit determines whether the DC system is operating normally based on the received charger output voltage and DC bus initial voltage. If so, it controls the first contact to open so that the step-down silicon chain is connected in series with the DC bus and connects the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system.

[0015] The voltage acquisition unit is used to acquire the DC bus voltage at multiple time points after the first contact is opened and the battery pack is connected to the DC power system, and to send the DC bus voltage at multiple time points to the control unit.

[0016] The control unit is used to determine whether the battery's normal load carrying capacity is qualified based on the DC bus voltage received at multiple time points. If the battery's normal load carrying capacity is qualified, it controls the second and third contacts to close.

[0017] The voltage acquisition unit is used to acquire the DC bus voltage after the second and third contacts are closed, and send the DC bus voltage to the control unit.

[0018] The control unit is used to determine whether the battery's shock resistance capability is qualified based on the received DC bus voltage. If the battery's shock resistance capability is qualified, it controls the first contact to close, the second contact to open, and the third contact to open.

[0019] The voltage acquisition unit is used to acquire the final DC bus voltage after the first contact is closed, the second contact is open, and the third contact is open, and then send the final DC bus voltage to the control unit.

[0020] The control unit is used to determine whether the final voltage of the received DC bus is higher than the set voltage judgment value. If it is, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

[0021] The beneficial effects of this invention are:

[0022] This invention provides an intelligent portable method for detecting open circuits in battery packs. By reducing the DC bus voltage on the charger of a DC power system, the battery pack is subjected to a short-term discharge under actual or simulated load to verify its load-carrying capacity and qualitatively assess its performance and condition. This method can automatically and periodically, or manually, perform a comprehensive check of the battery's effectiveness, promptly detecting issues such as open circuits in individual cells, battery pack switch malfunctions or disconnections, blown battery pack fuses, detached connecting wires, broken cross-layer wires, and loose screws. This verifies whether the system can handle normal loads and ensures the safe operation of the DC system. Simultaneously, this method can intelligently switch internal loads, simulating the simultaneous tripping or closing current of multiple circuit breakers, and dynamically detect bus voltage fluctuations and drops to verify the battery pack's ability to withstand superimposed impact loads. Attached Figure Description

[0023] Figure 1 Electrical schematic diagram of the battery pack open circuit detection device according to a specific embodiment of this application;

[0024] Figure 2 This is a wiring diagram of the battery pack open circuit detection device according to a specific embodiment of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0026] Specific Implementation Method 1: A smart portable method for detecting open circuits in battery packs, comprising:

[0027] Obtain the output voltage of the charger and the initial voltage of the DC power system. Determine whether the DC system is operating normally based on the output voltage of the charger and the initial voltage of the DC bus. If so, connect the step-down silicon chain in series with the DC bus and connect the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system. Determine whether the battery's normal load-carrying capacity is qualified based on the DC bus voltage at multiple time points.

[0028] If the battery's normal load carrying capacity is qualified, the simulated load is connected to the DC power system, and the impact resistance of the battery is judged based on the DC bus voltage after the simulated load is connected.

[0029] If the battery's impact resistance is qualified, disconnect the simulated load and short-circuit the step-down silicon chain to obtain the final DC bus voltage. If the final DC bus voltage is higher than the set voltage judgment value, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

[0030] Specifically, such as Figures 1 to 2 As shown, an intelligent portable method for detecting open circuits in battery packs can realize online monitoring of battery pack performance and dynamic verification of load capacity. Without making any modifications to the on-site DC system battery pack, based on the unidirectional conduction and automatic voltage reduction characteristics of the step-down silicon chain, the DC output voltage of the charger bus is appropriately reduced. The battery pack is then rapidly discharged using on-site load and additional simulated load. This method can both provide online intelligent qualitative diagnosis of battery performance and ensure the continuity of DC bus power supply.

[0031] Furthermore, methods for obtaining the charger output voltage and the initial DC bus voltage of the DC power supply system, and for determining whether the DC system is operating normally based on the charger output voltage and the initial DC bus voltage, include:

[0032] Set the standard values ​​for the charger output voltage and the DC bus voltage. Determine whether the obtained charger output voltage is equal to the set standard value and whether the initial DC bus voltage is higher than the standard value. If so, the DC system is operating normally; otherwise, the DC system is not operating normally.

[0033] Specifically, before testing the performance of the battery pack, the step-down silicon chain is short-circuited and ineffective. First, check the charger and DC bus voltage to determine whether the DC system is operating normally. Only after confirming that it is normal can the next step be carried out.

[0034] Furthermore, methods for determining whether the battery's conventional load-carrying capacity is qualified based on the DC bus voltage at multiple time points after the battery pack is connected to the DC power system include:

[0035] The DC bus voltage at the first time point, the second time point, the third time point, and the fourth time point are obtained after the step-down silicon chain is connected in series with the DC bus and connected to the DC power supply system.

[0036] The DC bus voltages at the first, second, third, and fourth time points are compared with the set DC bus voltage values ​​for the first, second, third, and fourth time points, respectively. If the DC bus voltage at any time point is lower than the corresponding set DC bus voltage value, the battery's normal load carrying capacity is deemed unqualified; otherwise, the battery's normal load carrying capacity is deemed qualified.

[0037] Specifically, the step-down silicon chain is put into operation to reduce the DC output voltage of the charger bus, thereby enabling the battery pack to bear the station's conventional DC load and be in a discharging state, testing the battery's conventional load-carrying capacity; during the test, it is determined whether the DC bus voltage is higher than the set value at multiple time points. If the DC bus voltage is lower than the set value at any time point, the battery's conventional load-carrying capacity is considered unqualified.

[0038] Furthermore, methods for determining whether a battery's shock resistance is up to standard based on the DC bus voltage after a simulated load is connected include:

[0039] The system continuously acquires the DC bus voltage after the simulated load is connected to the DC power system. It then determines whether the acquired DC bus voltage is less than the set standard value for DC bus voltage. If so, the battery's shock resistance is deemed unqualified; otherwise, the battery's shock resistance is deemed qualified.

[0040] Specifically, after the conventional load-bearing capacity test is passed, a simulated load is applied to simulate the impact load of the high-voltage circuit breaker opening and closing, based on the conventional load of the battery pack, to test the battery's impact resistance. During the impact process, the bus voltage is constantly checked to see if it is less than the set standard value of the DC bus voltage. If it is less than the set standard value of the DC bus voltage, the battery is considered to have insufficient impact resistance.

[0041] Furthermore, an intelligent portable method for detecting open circuits in a battery pack includes continuously acquiring the real-time output voltage of the charger and the real-time voltage of the DC bus when the step-down silicon chain is connected in series with the DC bus, determining whether the acquired real-time output voltage of the charger is equal to the set standard value of the charger output voltage and whether the initial voltage of the DC bus is higher than the standard value of the DC bus voltage, otherwise disconnecting the simulated load and short-circuiting the step-down silicon chain.

[0042] Specifically, during the discharge process, the charger output DC voltage and DC bus voltage are monitored online in real time. If the charger output voltage or DC bus voltage is abnormal, the discharge is immediately terminated and the system returns to normal operation.

[0043] When the set discharge time is up, the simulated load is disconnected, the step-down silicon chain is shorted, and the charger automatically supplies power to the conventional station DC load and charges the battery pack, and the DC power system returns to normal operation.

[0044] At the end of the discharge, if the final voltage of the DC bus is higher than the set voltage threshold, it indicates that the battery pack performance is basically good and can meet the actual needs of the substation. If the final voltage of the DC bus is lower than the set voltage threshold, it indicates that the battery pack capacity is insufficient and the battery performance has declined significantly. A standard discharge capacity test should be conducted as soon as possible for accurate verification.

[0045] Furthermore, the step-down silicon chain includes 38 diodes connected in sequence, each of which is a 10A10 diode.

[0046] Specifically, the step-down silicon chain, based on the unidirectional conduction and automatic step-down characteristics of diodes, appropriately reduces the DC output voltage of the charger's bus.

[0047] Furthermore, the standard value for the charger's output voltage is 232V, and the standard value for the DC bus voltage is 198V.

[0048] Furthermore, the DC bus voltage at the first time point, the DC bus voltage at the second time point, the DC bus voltage at the third time point, and the DC bus voltage at the fourth time point are the DC bus voltage at the 1st second, the 6th second, the 30th second, and the 90th second after the step-down silicon chain is connected in series with the DC bus and connected to the DC power supply system, respectively.

[0049] The first DC bus voltage setting is 10V, the second DC bus voltage setting is 15V, the third DC bus voltage setting is 20V, and the fourth DC bus voltage setting is 25V.

[0050] Specific Implementation Method 2: An intelligent portable anti-open circuit detection device for battery packs includes: a charger, a voltage acquisition unit, a step-down silicon chain, a battery pack, a simulated load, and a control unit;

[0051] The positive output terminal of the charger is connected to one end of the positive terminal of the DC bus through the first contact, and the negative output terminal of the charger is connected to one end of the negative terminal of the DC bus. The charger is used to supply power to the DC bus.

[0052] One end of the step-down silicon chain is connected to the positive output terminal of the charger, and the other end of the step-down silicon chain is connected to one end of the positive terminal of the DC bus.

[0053] The positive terminal of the simulated load is connected to the positive terminal of the DC bus through the second contact, and the negative terminal of the simulated load is connected to the negative terminal of the DC bus through the third contact.

[0054] The voltage acquisition unit is used to acquire the output voltage of the DC power system charger and the initial voltage of the DC bus when the first contact is closed, the second contact is open, and the third contact is open, and to transmit the output voltage of the DC power system charger and the initial voltage of the DC bus to the control unit.

[0055] The control unit determines whether the DC system is operating normally based on the received charger output voltage and DC bus initial voltage. If so, it controls the first contact to open so that the step-down silicon chain is connected in series with the DC bus and connects the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system.

[0056] The voltage acquisition unit is used to acquire the DC bus voltage at multiple time points after the first contact is opened and the battery pack is connected to the DC power system, and to send the DC bus voltage at multiple time points to the control unit.

[0057] The control unit is used to determine whether the battery's normal load carrying capacity is qualified based on the DC bus voltage received at multiple time points. If the battery's normal load carrying capacity is qualified, it controls the second and third contacts to close.

[0058] The voltage acquisition unit is used to acquire the DC bus voltage after the second and third contacts are closed, and send the DC bus voltage to the control unit.

[0059] The control unit is used to determine whether the battery's shock resistance capability is qualified based on the received DC bus voltage. If the battery's shock resistance capability is qualified, it controls the first contact to close, the second contact to open, and the third contact to open.

[0060] The voltage acquisition unit is used to acquire the final DC bus voltage after the first contact is closed, the second contact is open, and the third contact is open, and then send the final DC bus voltage to the control unit.

[0061] The control unit is used to determine whether the final voltage of the received DC bus is higher than the set voltage judgment value. If it is, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

[0062] Specifically, during normal operation of the DC power supply system, the charger output is connected to the DC bus via the first contact, and the DC power supply system operates in the same manner as a regular DC power supply. When it is necessary to test the effectiveness of the battery pack, the first contact between the charger output and the DC bus is disconnected. Utilizing the unidirectional conduction and automatic voltage reduction characteristics of the step-down silicon chain, the DC output voltage of the charger bus is appropriately reduced while ensuring that the charger is online. This allows the battery pack to bear the regular DC load of the station, verifying the battery pack's regular load-carrying capacity. Then, the second and third contacts are closed to connect a simulated load, and the battery pack is discharged to verify its impact resistance.

[0063] Furthermore, the step-down silicon chain includes 38 diodes connected in sequence. The anode of the first diode is connected to the positive output terminal of the charger, the cathode of the 38th diode is connected to one end of the positive DC bus, and the cathode of the i-th diode is connected to the anode of the (i+1)-th diode. Each diode is a 10A10 diode.

[0064] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A smart portable method for detecting open circuits in battery packs, characterized in that, include: Obtain the output voltage of the charger and the initial voltage of the DC power system. Determine whether the DC system is operating normally based on the output voltage of the charger and the initial voltage of the DC bus. If so, connect the step-down silicon chain in series with the DC bus and connect the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system. Determine whether the battery pack's normal load-carrying capacity is qualified based on the DC bus voltage at multiple time points after the battery pack is connected to the DC power system. If the battery's normal load carrying capacity is qualified, the simulated load is connected to the DC power system, and the impact resistance of the battery is judged based on the DC bus voltage after the simulated load is connected. If the battery's impact resistance is qualified, disconnect the simulated load and short-circuit the step-down silicon chain to obtain the final DC bus voltage. If the final DC bus voltage is higher than the set voltage judgment value, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

2. The intelligent portable method for detecting open circuits in battery packs according to claim 1, characterized in that: Methods for obtaining the charger output voltage and the initial DC bus voltage of a DC power supply system, and for determining whether the DC system is operating normally based on the charger output voltage and the initial DC bus voltage, include: Set the standard values ​​for the charger output voltage and the DC bus voltage. Determine whether the obtained charger output voltage is equal to the set standard value and whether the initial DC bus voltage is higher than the standard value. If so, the DC system is operating normally; otherwise, the DC system is not operating normally.

3. The intelligent portable method for detecting open circuits in battery packs according to claim 1, characterized in that: Methods for determining whether a battery's conventional load-carrying capacity is qualified based on the DC bus voltage at multiple time points after the battery pack is connected to the DC power system include: The DC bus voltage at the first time point, the second time point, the third time point, and the fourth time point are obtained after the step-down silicon chain is connected in series with the DC bus and connected to the DC power supply system. The DC bus voltages at the first, second, third, and fourth time points are compared with the set DC bus voltage values ​​for the first, second, third, and fourth time points, respectively. If the DC bus voltage at any time point is lower than the corresponding set DC bus voltage value, the battery's normal load carrying capacity is deemed unqualified; otherwise, the battery's normal load carrying capacity is deemed qualified.

4. The intelligent portable method for detecting open circuits in battery packs according to claim 1, characterized in that: Methods for determining whether a battery's shock resistance is up to standard based on the DC bus voltage after a simulated load is connected include: The system continuously acquires the DC bus voltage after the simulated load is connected to the DC power system. It then determines whether the acquired DC bus voltage is less than the set standard value for DC bus voltage. If so, the battery's shock resistance is deemed unqualified; otherwise, the battery's shock resistance is deemed qualified.

5. The intelligent portable method for detecting open circuits in battery packs according to claim 1, characterized in that: It also includes continuously acquiring the real-time output voltage of the charger and the real-time voltage of the DC bus when the step-down silicon chain is connected in series with the DC bus, determining whether the acquired real-time output voltage of the charger is equal to the set standard value of the charger output voltage and whether the initial voltage of the DC bus is higher than the standard value of the DC bus voltage. Otherwise, disconnect the simulated load and short-circuit the step-down silicon chain.

6. The intelligent portable method for detecting open circuits in battery packs according to claim 1, characterized in that: The step-down silicon chain comprises 38 diodes connected in sequence, each of which is a 10A10 diode.

7. The intelligent portable method for detecting open circuits in battery packs according to claim 2, characterized in that: The standard output voltage of the charger is 232V, and the standard DC bus voltage is 198V.

8. The intelligent portable method for detecting open circuits in battery packs according to claim 3, characterized in that: The DC bus voltage at the first time point, the DC bus voltage at the second time point, the DC bus voltage at the third time point, and the DC bus voltage at the fourth time point are the DC bus voltage at the 1st second, the 6th second, the 30th second, and the 90th second after the step-down silicon chain is connected in series with the DC bus and connected to the DC power supply system. The first DC bus voltage setting is 10V, the second DC bus voltage setting is 15V, the third DC bus voltage setting is 20V, and the fourth DC bus voltage setting is 25V.

9. A smart portable battery pack open-circuit detection device, characterized in that: include: Charger, voltage acquisition unit, step-down silicon chain, battery pack, analog load and control unit; The positive output terminal of the charger is connected to one end of the positive terminal of the DC bus through the first contact, and the negative output terminal of the charger is connected to one end of the negative terminal of the DC bus. The charger is used to supply power to the DC bus. One end of the step-down silicon chain is connected to the positive output terminal of the charger, and the other end of the step-down silicon chain is connected to one end of the positive terminal of the DC bus. The positive terminal of the simulated load is connected to the positive terminal of the DC bus through the second contact, and the negative terminal of the simulated load is connected to the negative terminal of the DC bus through the third contact. The voltage acquisition unit is used to acquire the output voltage of the DC power system charger and the initial voltage of the DC bus when the first contact is closed, the second contact is open, and the third contact is open, and to transmit the output voltage of the DC power system charger and the initial voltage of the DC bus to the control unit. The control unit determines whether the DC system is operating normally based on the received charger output voltage and DC bus initial voltage. If so, it controls the first contact to open so that the step-down silicon chain is connected in series with the DC bus and connects the battery pack to the DC power system so that the battery pack can bear the normal load of the DC power system. The voltage acquisition unit is used to acquire the DC bus voltage at multiple time points after the first contact is opened and the battery pack is connected to the DC power system, and to send the DC bus voltage at multiple time points to the control unit. The control unit is used to determine whether the battery's normal load carrying capacity is qualified based on the DC bus voltage received at multiple time points. If the battery's normal load carrying capacity is qualified, it controls the second and third contacts to close. The voltage acquisition unit is used to acquire the DC bus voltage after the second and third contacts are closed, and send the DC bus voltage to the control unit. The control unit is used to determine whether the battery's shock resistance capability is qualified based on the received DC bus voltage. If the battery's shock resistance capability is qualified, it controls the first contact to close, the second contact to open, and the third contact to open. The voltage acquisition unit is used to acquire the final DC bus voltage after the first contact is closed, the second contact is open, and the third contact is open, and then send the final DC bus voltage to the control unit. The control unit is used to determine whether the final voltage of the received DC bus is higher than the set voltage judgment value. If it is, the battery pack performance is deemed qualified; otherwise, the battery pack performance is deemed unqualified.

10. The intelligent portable anti-open circuit detection device for battery packs according to claim 9, characterized in that: The step-down silicon chain includes 38 diodes connected in sequence. The anode of the first diode is connected to the positive output terminal of the charger, the cathode of the 38th diode is connected to one end of the positive DC bus, and the cathode of the i-th diode is connected to the anode of the (i+1)-th diode. Each diode is a 10A10 diode.

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