A portable feedback battery maintenance control system

Abstract

The present invention discloses a portable feedback type battery maintenance control system, including a charger, a battery pack, a system load, a battery inspection instrument, a portable feedback type device, a system monitor and a switch K1-K5; wherein the system load is connected to the DC bus through the switch K2; the input end of the charger is connected to the AC power grid, and the output end is connected to the DC bus through the switch K1; the input end of the battery pack is connected to the DC bus through the switch K3, and is electrically connected to the input end of the portable feedback type device through the switch K4; the output end of the battery pack is electrically connected to the input end of the battery inspection instrument; the output end of the portable feedback type device is connected to the AC power grid through the switch K5; the system monitor performs data transmission with the charger, the battery inspection instrument and the portable feedback type device. The present invention has the advantages of online linearity, convenient economy, energy saving, safety and reliability, and high precision.

Description

Technical Field

[0001] The present invention relates to the field of battery maintenance, and more specifically, to a portable feedback type battery maintenance control system. Background Art

[0002] In order to ensure the safe operation of the power system, the control and protection equipment of power plants and substations are all powered by DC power, where the DC power is provided by a high-frequency switching power supply module for the power operation power supply and a battery pack. When the power system is normal, the DC power is supplied by the high-frequency switching power supply module for the power operation power supply, and the battery pack is in standby mode. When an accident occurs at the AC power supply end of the power system, causing the AC power outage, the high-frequency switching power supply module for the power operation power supply will not work properly, and the battery pack will act as the power output end to ensure the normal operation of important terminal equipment. Therefore, the reliable operation of the battery pack is one of the important guarantees for the normal operation of the power system. At present, the most direct and reliable way to determine whether the capacity of the battery pack meets the requirements is to perform a discharge maintenance test on the battery.

[0003] At present, there are three types of equipment for battery maintenance in the industry. The first type is fixed active inverter equipment, the second type is fixed energy-consuming resistor discharge equipment, and the third type is portable energy-consuming discharge equipment. The first and second types of discharge equipment are fixedly installed on DC power supply equipment, but due to system planning and design and other reasons, only a very small number of DC power supply systems now contain such fixed maintenance equipment. The third type of portable energy-consuming discharge equipment is more flexible in application and can be purchased later, so it is now more widely used.

[0004] When maintaining a battery pack, constant current discharge is required. Currently, most portable energy-consuming discharge devices use PTC resistors to achieve constant current discharge by controlling the temperature of the PTC resistor. This control method is easily affected by the ambient temperature, and the steady current adjustment speed is slow, and the discharge current stability is poor, which affects the accuracy of the battery pack capacity calculation. In addition, during the operation of the energy-consuming discharge device, heat is dissipated through the resistor, which will cause the temperature of the discharge device itself and the surrounding environment to rise, causing a certain impact on the operation of surrounding equipment, and also wasting a certain amount of energy. Currently, portable energy-consuming discharge devices all use offline maintenance methods, which require the use of spare battery packs, increasing a certain amount of system investment costs. Summary of the invention

[0005] The purpose of the present invention is to solve one or more of the above-mentioned defects and design a portable feedback battery maintenance control system.

[0006] In order to achieve the above invention purpose, the technical solution adopted is:

[0007] A portable feedback type battery maintenance control system, comprising a charger, a battery pack, a system load, a battery inspection instrument, a portable feedback type device, a system monitor and switches K1-K5;

[0008] The system load is connected to the DC bus through switch K2;

[0009] The input end of the charger is connected to the AC grid, and the output end is connected to the DC bus through switch K1;

[0010] The input end of the battery pack is connected to the DC bus through the switch K3, and is electrically connected to the input end of the portable feedback device through the switch K4; the output end of the battery pack is electrically connected to the input end of the battery inspection instrument;

[0011] The output end of the portable feedback device is connected to the AC power grid through switch K5;

[0012] The system monitor transmits data with the charger, battery inspector and portable feedback device.

[0013] The charger includes a plurality of high-frequency switching power supply subunits for the electric operating power supply.

[0014] The portable feedback device includes a DC / AC main circuit, a control circuit, a sampling circuit, a communication circuit, a display terminal and a keyboard; the output end of the sampling circuit is electrically connected to the input end of the control circuit, the control circuit transmits data with the DC / AC main circuit and the communication circuit, and the display terminal and the keyboard are both electrically connected to the control circuit.

[0015] The communication circuit is a circuit including an RS485 chip or a CAN chip.

[0016] When the system is operating normally, switches K1, K2, and K3 are all closed, K4 and K5 are all open, and the portable feedback device is not connected to the system. The AC grid supplies power to the charger, which converts AC power into DC power and supplies power to the DC bus through K1, while replenishing power to the battery pack through K3. The DC bus supplies power to the system load through K2, assuming that the system load current is Io. The battery inspection instrument detects the working status of the battery pack in real time and uploads the status information to the system monitor in real time.

[0017] When the battery pack needs to be discharged for maintenance, the DC input of the portable feedback device is connected to switch K4, and the AC output is connected to switch K5. At this time, switches K4 and K5 remain disconnected. Connect the communication port of the portable feedback device to the communication port of the system monitor to ensure normal communication.

[0018] After the above connection is correct, turn on the power supply of the portable feedback device. If the display terminal shows that the battery pack is in normal condition, set the corresponding discharge parameters. Mainly the battery pack discharge termination voltage, battery pack discharge current value and charger output voltage. The setting principle of the charger output voltage is lower than the set battery pack discharge termination voltage and higher than the low voltage limit allowed by the DC bus. After the setting is completed, close switch K4. If the display terminal shows that the battery pack is in normal condition, the maintenance process of the battery pack can be started. After the maintenance process is started, if the display terminal shows that the battery discharge is normal, close switch K5. The portable feedback device will automatically adjust its input current value according to the battery pack discharge current value and the system load current Io to ensure that the battery pack discharge current value remains constant at the set value. When the set battery pack discharge termination condition is reached, the portable feedback device will automatically stop working, issue a prompt sound, and output the data analysis results. At the same time, the maintenance end information will be uploaded to the system monitor. The system monitor will automatically set the charger output voltage to the equalization charging voltage to supply power to the DC bus and replenish the battery pack with electric energy. After completing the maintenance of the battery pack, disconnect switches K5 and K4, cut off the power supply of the portable feedback device, disconnect the communication line between the portable feedback device and the system monitor, and separate the portable feedback device from the system.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) The portable feedback device can be put into the system through a switch, and the battery pack does not need to be disconnected from the system, thereby realizing online maintenance of the battery pack and improving the power supply reliability of the DC power supply system;

[0021] 2) The portable feedback device can be put into the system as needed, and no backup battery pack is required, which improves the flexibility of battery operation and maintenance in the DC power supply system and reduces operation and maintenance costs;

[0022] 3) The portable feedback device can feed back part of the energy of the battery pack to the power grid, thus avoiding certain energy waste;

[0023] 4) A variety of protection circuits are set in the portable feedback device to ensure that the battery maintenance process is safe and reliable without affecting the normal operation of the system;

[0024] 5) The portable feedback device is internally provided with a control circuit, which can quickly adjust the input current value, ensure the stability of the battery pack discharge current, and improve the accuracy of the battery pack capacity calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a system architecture diagram of the present invention;

[0026] Figure 2This is a schematic diagram of the structure of the portable feedback device of the present invention. DETAILED DESCRIPTION

[0027] The drawings are for illustrative purposes only and should not be construed as limiting the present patent;

[0028] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0029] Example 1

[0030] A portable feedback battery maintenance control system, please refer to Figure 1 , including charger, battery pack, system load, battery inspection instrument, portable feedback device, system monitor and switches K1-K5;

[0031] The system load is connected to the DC bus through switch K2;

[0032] The input end of the charger is connected to the AC grid, and the output end is connected to the DC bus through switch K1;

[0033] The input end of the battery pack is connected to the DC bus through the switch K3, and is electrically connected to the input end of the portable feedback device through the switch K4; the output end of the battery pack is electrically connected to the input end of the battery inspection instrument;

[0034] The output end of the portable feedback device is connected to the AC power grid through switch K5;

[0035] The system monitor transmits data with the charger, battery inspector and portable feedback device.

[0036] The charger includes a plurality of high-frequency switching power supply subunits for the electric operating power supply.

[0037] The portable feedback device is described in Figure 2 , including a DC / AC main circuit, a control circuit, a sampling circuit, a communication circuit, a display terminal and a keyboard; wherein the output end of the sampling circuit is electrically connected to the input end of the control circuit, the control circuit transmits data with the DC / AC main circuit and the communication circuit, and the display terminal and the keyboard are both electrically connected to the control circuit.

[0038] The communication circuit is a circuit including an RS485 chip or a CAN chip.

[0039] Assume that the system is a 220VDC system and the capacity of the battery pack is 200AH. Therefore, the discharge current value of the battery pack is 0.1*200=20A, the equalization charge voltage is 242VDC, the float charge voltage is 230VDC, the discharge termination voltage is 198VDC, and the minimum allowable voltage of the DC bus is 192.5VDC.

[0040] When the system is operating normally, switches K1, K2, and K3 are all closed, K4 and K5 are all open, and the portable feedback device is not connected to the system. The AC grid supplies power to the charger, which converts AC power into DC power and supplies power to the DC bus through K1, while replenishing power to the battery pack through K3. The output voltage of the charger generally operates at a floating charge voltage of 230VDC.

[0041] When the battery pack needs to be discharged for maintenance, the DC input of the portable feedback device is connected to switch K4, and the AC output is connected to switch K5. Switches K4 and K5 remain disconnected. Connect the communication port of the portable feedback device to the communication port of the system monitor to ensure normal communication.

[0042] After the above connection is correct, turn on the power supply of the portable feedback device. If the display terminal shows that the battery pack is in normal condition, set the corresponding discharge parameters. The battery pack discharge termination voltage is set to 198VDC, the battery pack discharge current value is set to 20A, and the charger output voltage is set to 195VDC (it can be set between 192.5 and 198VDC). After the setting is completed, close switch K4. If the display terminal shows that the battery pack is in normal condition, the maintenance process of the battery pack can be started. After the maintenance process is started, if the display terminal shows that the battery discharge is normal, close switch K5. The portable feedback device will automatically adjust its own input current value according to the battery pack discharge current value and the system load current Io to ensure that the discharge current value of the battery pack remains constant at the set value. Assuming that the system load current is 5A, the portable feedback device will automatically adjust its own input current to 15A. When the system load current becomes 10A, the portable feedback device will automatically adjust its own input current to 10A, and always keep the discharge current of the battery pack at 20A. When the terminal voltage of the battery pack drops to 198VDC, the portable feedback device will automatically stop working, sound a prompt, and output the data analysis results, while uploading them to the system monitor. The system monitor will automatically set the output voltage of the charger to the equalization voltage of 242VDC to supply power to the DC bus and replenish the battery pack. After completing the maintenance of the battery pack, disconnect switches K5 and K4, cut off the power supply of the portable feedback device, disconnect the communication line between the portable feedback device and the system monitor, and separate the portable feedback device from the system.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A portable feedback battery maintenance control system, characterized in that: It includes charger, battery pack, system load, battery inspection instrument, portable feedback device, system monitor and switches K1-K5; The system load is connected to the DC bus through switch K2; The input end of the charger is connected to the AC grid, and the output end is connected to the DC bus through switch K1; The input end of the battery pack is connected to the DC bus through the switch K3, and is electrically connected to the input end of the portable feedback device through the switch K4; the output end of the battery pack is electrically connected to the input end of the battery inspection instrument; The output end of the portable feedback device is connected to the AC power grid through switch K5; The system monitor transmits data with the charger, battery inspector and portable feedback device; When the system is operating normally, switches K1, K2, and K3 are all in a closed state, and K4 and K5 are both in a disconnected state. The AC grid supplies power to the charger, which converts the AC power into DC power and supplies power to the DC bus through K1, while replenishing power to the battery pack through K3. When the battery pack needs to be discharged for maintenance, the DC input end of the portable feedback device is connected to the switch K4, and the AC output end is connected to the switch K5. At this time, switches K4 and K5 remain disconnected, and the communication port of the portable feedback device is connected to the communication port of the system monitor to ensure normal communication. After the above connections are correct, turn on the power supply of the portable feedback device. If the display terminal shows that the battery pack is in normal condition, set the corresponding discharge parameters, including the battery pack discharge termination voltage, battery pack discharge current value and charger output voltage. The charger output voltage should be set lower than the set battery pack discharge termination voltage and higher than the DC bus allowable low voltage limit. After the setting is completed, close switch K4. If the display terminal shows that the status is normal, the maintenance process of the battery pack can be started. After the maintenance process is started, if the display terminal shows that the battery discharge is normal, close switch K5. The portable feedback device will automatically adjust its own input current value according to the battery pack discharge current value and the system load current Io to ensure that the battery pack discharge current value remains constant at the set value; when the set battery pack discharge termination condition is reached, the portable feedback device will automatically stop working, sound a prompt, and output the data analysis results. At the same time, the maintenance end information will be uploaded to the system monitor. The system monitor will automatically set the output voltage of the charger to the equalization charging voltage to supply power to the DC bus and replenish power for the battery pack at the same time; After completing the maintenance of the battery pack, disconnect switches K5 and K4, cut off the power supply of the portable feedback device, disconnect the communication line between the portable feedback device and the system monitor, and separate the portable feedback device from the system; The charger includes a plurality of high frequency switching power supply subunits for the electric operating power supply.

2. A portable feedback battery maintenance control system according to claim 1, characterized in that: The portable feedback device includes a DC / AC main circuit, a control circuit, a sampling circuit, a communication circuit, a display terminal and a keyboard; wherein the output end of the sampling circuit is electrically connected to the input end of the control circuit, the control circuit transmits data with the DC / AC main circuit and the communication circuit, and the display terminal and the keyboard are both electrically connected to the control circuit.

3. A portable feedback battery maintenance control system according to claim 2, characterized in that: The communication circuit is a circuit including an RS485 chip or a CAN chip.

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