Intrinsically safe lithium battery system for coal mine

Abstract

The invention relates to an intrinsically safe lithium battery system. Comprising an MCU main control module, a battery electric quantity detection module, a current detection module, a switch module, a voltage conversion module, a 485 isolation communication module, an intrinsically safe isolation voltage stabilization module, an intrinsically safe current monitoring module, an encapsulated battery box shell, an intrinsically safe lithium battery pack, an encapsulated colloid and an external interface. The system has good stability, the adaptability and flexibility of the whole module system can be adjusted according to mutual cooperation of all the modules, in this way, the state of the battery system is monitored in real time, the reliability of the robot in the running process can be kept, and the running safety of equipment is improved; and a novel intrinsically safe lithium battery system is created to provide energy supplementation for an operation machine in a special environment under a mine.

Description

Technical Field

[0001] The invention belongs to the technical field of equipment for coal mines, and in particular relates to an intrinsically safe lithium battery system for coal mines. Background Art

[0002] At present, in the production process of coal mines in my country, due to the complex operating environment, the stability and safety of mining products are related to the life safety of underground workers. Large explosion-proof equipment cannot be used in some narrow spaces, and small intrinsically safe equipment without backup batteries will cause power outages to underground workers and coal mine production. In addition, the battery system cannot detect the output current and voltage, and it is also impossible to power off abnormal machines in time. It is impossible to monitor the power consumption of the equipment in real time through the host computer and plan the replacement of the equipment in advance, so safety cannot be guaranteed. Summary of the invention

[0003] (I) Purpose of the invention

[0004] In order to overcome the above shortcomings, the purpose of the present invention is to provide an intrinsically safe lithium battery system for coal mines to solve the above technical problems.

[0005] (II) Technical solution

[0006] To achieve the above objectives, the technical solutions provided by this application are as follows:

[0007] An intrinsically safe lithium battery system for coal mines includes an MCU main control module, a battery power detection module, a current detection module, a switch module, a voltage conversion module, a 485 isolation communication module, an intrinsically safe isolation voltage regulator module, an intrinsically safe current monitoring module, a cast-sealed battery box shell, an intrinsically safe lithium battery pack, a cast-sealed colloid, and an external interface. According to the internal working process of the system, the output current of the intrinsically safe lithium battery pack first enters the voltage conversion module through an anti-reverse connection protection circuit and a current limiting protection circuit. The voltage conversion module outputs 3.3V and 5V DC power supplies respectively, wherein the 3.3V DC power supply is supplied to the MCU main control module. The 5V DC power supply is used to power the 485 isolation communication module; the current then passes through the battery power detection module and the current detection module, and the battery power detection module and the current detection module output the analog quantity of the corresponding detection signal to the MCU main control module according to the internal algorithm for data processing, storage and external transmission; the current after passing through the detection module passes through the switch module, the intrinsically safe isolation voltage stabilization module, the intrinsically safe current monitoring module and the external interface in sequence; the system is protected by the encapsulated battery box shell; when working, the external device controls and communicates with the MCU main control module through the 485 isolation communication module to monitor the power consumption status of the equipment in real time.

[0008] Preferably, the MCU main control module controls the initialization output of the two power supply circuits by detecting the high and low levels of the IO port, monitors the battery voltage and each output current in real time through the analog-to-digital signal pin, and also transmits information to external devices that support the 485 communication protocol and controls the switch circuit.

[0009] Preferably, the battery power detection module and the current detection module can respectively monitor the battery power and the current size of each line in real time, and output analog signals that comply with the protocol, and the MCU main control microcontroller processes the output data.

[0010] Preferably, the switch module adopts a two-stage field effect tube control circuit, the front-stage small voltage controls the rear-stage large voltage, and the MUC microcontroller controls the start and stop of the switch module according to the received communication signal.

[0011] Preferably, the voltage conversion module includes two paths, one of which uses a low-power LDO power conversion chip to power the entire system internal operation, and the other uses an isolated power supply module to power the isolated external communication signal according to the requirements of intrinsically safe equipment.

[0012] Preferably, TTL serial port communication is used between the 485 isolation communication module and the MCU main control module, and the TTL serial port signal and the communication chip control signal are isolated by optical coupling and the single-chip microcomputer to ensure the stability and security of communication. The 485 isolation communication module can communicate with external devices that support the 485 communication protocol.

[0013] Preferably, the intrinsically safe isolation voltage regulator module adopts an isolation power supply voltage regulator module that meets the electrical intrinsic safety requirements to isolate the intrinsically safe power supply from the non-intrinsically safe power supply.

[0014] Preferably, the intrinsically safe current monitoring module uses the LTC4380 chip to combine a new intrinsically safe monitoring circuit to monitor the current in real time and thus control the power supply output energy.

[0015] Preferably, the outer shell of the cast-in-place battery box is made of 304 stainless steel, the front end protrudes with an aviation plug connected to the power supply equipment, the rear end is designed with a change handle, and the colloid filled inside the cast-in-place colloid is epoxy resin colloid, the external connectors are three aviation plugs, one is a four-core socket for 485 communication signal and switch signal detection, and the other two are power output interfaces, the aviation plugs are isolated from the internal system, the system contains an independent charging interface, a DC_05 interface insulated from the outer shell, and all interfaces have independent rubber plugs on the outside.

[0016] Preferably, the intrinsically safe lithium battery pack comprises intrinsically safe lithium battery cells, the intrinsically safe battery cells are connected in a three-series and two-parallel manner, and the battery is provided with a charge and discharge protection circuit for a single intrinsically safe lithium battery cell.

[0017] Beneficial effects:

[0018] This intrinsically safe lithium battery system for coal mines can monitor the voltage and current of intrinsically safe equipment in real time, and cut off the power supply in time for protection when the power load is abnormal. According to the needs, the system can start and stop each power supply. This lithium battery system improves the safety and reliability of intrinsically safe power supply. The battery system is connected with a quick-connect aviation plug, which is quick and convenient to replace the power, creating a new power supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the MCU main control module and the power detection module;

[0020] Figure 2 is a schematic diagram of a voltage conversion module;

[0021] Figure 3 is a schematic diagram of the switch module;

[0022] Figure 4 This is a schematic diagram of the 485 isolated communication module;

[0023] Figure 5 is a schematic diagram of the current detection module;

[0024] Figure 6 It is a schematic diagram of an intrinsically safe isolated voltage regulator module;

[0025] Figure 7 is a schematic diagram of an intrinsically safe current monitoring module;

[0026] Figure 8 This is the external structure diagram of the battery box. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following is a detailed description of the present invention in conjunction with the specific implementation methods and with reference to the attached drawings. Figure 1-8 , the present invention is further described in detail. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0028] The present invention provides an intrinsically safe lithium battery system for coal mines, comprising an MCU main control module, a battery power detection module, a current detection module, a switch module, a voltage conversion module, a 485 isolation communication module, an intrinsically safe isolation voltage stabilization module, an intrinsically safe current monitoring module, a cast-sealed battery box shell, an intrinsically safe lithium battery pack, a cast-sealed colloid and an external interface.

[0029] The MCU main control module of the above-mentioned intrinsically safe lithium battery system for coal mines is as follows: Figure 1 The circuit is composed of a single-chip microcomputer STM32F103C8T6 (1-1), including a crystal oscillator circuit, a single-chip microcomputer power filter circuit, a reset circuit, a chip burning port and a serial port debugging circuit. The chip resources are allocated according to the requirements of the entire circuit system, including an isolated 485 communication serial port, a debugging serial port, two current detection analog to digital IO ports, one power detection analog to digital IO port, two power switch signal IO ports, and one external control switch signal IO port.

[0030] The power detection module of the intrinsically safe lithium battery system for coal mines is as follows: Figure 1 The battery charge detection circuit calculates the voltage divider resistor value based on the maximum voltage to be detected and the withstand voltage value of the chip analog-to-digital pin. The circuit is composed of high-precision resistors, chip pin protection diodes and filter capacitors.

[0031] The current detection module of the intrinsically safe lithium battery system for coal mines is as follows Figure 5 The circuit uses the INA199A1DCKR bidirectional, zero-drift current sensing amplifier (5-1). The circuit calculates the voltage difference across the mounting resistor based on the input voltage of the bidirectional port of the operational amplifier inside the chip. The value of the detection resistor is calculated based on the maximum current required by the entire back-end load and the withstand voltage of the analog-to-digital port. The load resistor value can be adjusted according to the different current requirements of the back-end. The analog output end has a corresponding filter and diode voltage protection circuit.

[0032] The two-way switch module of the above-mentioned intrinsically safe lithium battery system for coal mines is as follows Figure 3 The front stage of the switch circuit uses an N-channel field effect transistor (3-1) to control the back-end P-channel field effect transistor (3-2), and the small signal controls the back-end high-power field effect transistor through the front-end field effect transistor to realize switching.

[0033] The voltage conversion module of the intrinsically safe lithium battery system for coal mines is as follows: Figure 2 The voltage conversion circuit includes two voltage conversion circuits. The first voltage conversion circuit is a low-power 12V to 3.3V power supply circuit. The circuit uses a low-power HT7533-A linear regulator (2-1) to convert the battery input power supply. Corresponding decoupling capacitors are placed at the chip input and output ends, and a voltage regulator diode is additionally placed at the output end. The second isolation voltage conversion circuit converts 12V into 5V. Decoupling capacitors are placed at the front and rear ends of the module respectively, and fuses, current limiting resistors, and voltage regulators are additionally placed at the rear end of the module. This module is an isolated power supply module. The front and rear ends do not share a common ground, and the power output is isolated from the front end output. The battery power is connected to the power conversion module after passing through a transient diode, a total current fuse, and a rectifier diode.

[0034] The 485 isolated communication module of the intrinsically safe lithium battery system for coal mines is as follows: Figure 4 The 485 communication module uses the low-power SN65HVD3082ED chip (4-1) as the main communication chip. According to the required requirements, a TLP2362 optocoupler (4-2) is placed at the serial port protocol end of the chip to isolate the signal reception and transmission, and a TLP521GB-S optocoupler (4-3) is placed at the chip communication control end to isolate the microcontroller and the communication chip. The A and B signal lines at the output end of the communication chip are connected to a 160mA self-recovery fuse (4-4), a 300mA one-time fuse (4-5) and a current limiting resistor, and a bidirectional voltage regulator circuit (4-6) is placed between the A and B signal lines.

[0035] The intrinsically safe isolation voltage stabilizing module of the intrinsically safe lithium battery system for coal mines is as follows: Figure 6 The battery power passes through the transient diode and the total current fuse (6-2) and flows into the front end of the intrinsically safe voltage stabilizing module. There are two intrinsically safe voltage stabilizing modules in total, and separate current fuse bypass capacitors are placed at the input ends. The module is based on the URB2412LD-20WR3 low-power, fast-start, high-conversion efficiency isolated voltage stabilizing power supply module (6-1), which is coordinated with peripheral circuits.

[0036] The intrinsically safe current monitoring module of the intrinsically safe lithium battery system for coal mines is as follows: Figure 7 The intrinsically safe current monitoring module is mainly placed at the back end of each intrinsically safe voltage stabilizing module for current detection. Two LTC4380 chips (7-1) and corresponding peripheral circuits are placed on each path. When the voltage of the detection pin exceeds the preset range, the field effect tube is turned off. The voltage preset value can be changed according to the specific requirements. The size of the detection resistor (7-2) is replaced. Two surge detection chips are mounted on each output to improve the reliability of the module.

[0037] The above-mentioned sealed battery box shell of the intrinsically safe lithium battery system for coal mines is as follows Figure 8 It uses an innovative structure and is made of 304 stainless steel. It is designed according to the size of the internal lithium battery and the circuit board. The front end is protruding with an aviation plug to connect to the power supply equipment. In addition, a special handle is designed at the rear end to facilitate equipment replacement.

[0038] The intrinsically safe lithium battery pack of the intrinsically safe lithium battery system for coal mines mentioned above uses intrinsically safe lithium batteries. The battery is composed of three internal battery cells in series and two in parallel, and the battery contains a charge and discharge protection circuit for a single battery cell, which can realize overcharge and over-discharge protection of the battery cell.

[0039] The above-mentioned encapsulating colloid and external interface of the intrinsically safe lithium battery system for coal mines use epoxy resin colloid with high hardness, cold and heat resistance, moisture and water resistance, high bonding strength, insulation and pressure resistance, good sealing, hardness and shock resistance, environmental protection and low odor as the internal filling colloid. The DC level potting glue has no bubbles inside, and the colloid is stable and non-corrosive. The aviation plug is mainly divided into three aviation plugs. One is a four-core socket for 485 communication signal and switch signal detection. The interface line is completely isolated from the internal main control module and the power supply circuit. The other two are power output interfaces, which are completely isolated from the internal battery power supply. An intrinsically safe lithium battery system for coal mines contains an independent system charging interface, which is insulated from the outer shell and can charge the intrinsically safe lithium battery pack separately. The interface is a standard DC_05 interface. And all interfaces have independent rubber plugs on the outside to prevent dust and water vapor from entering.

[0040] The electrical equipment is connected to the intrinsically safe lithium battery system in sequence through aviation plugs. The connection order is: four-core data communication aviation plug, two-core power output aviation plug 1, and two-core power output aviation plug 2. After the connection is completed, the equipment is powered on.

[0041] The execution modules of the system include: MCU main control module, battery power detection module, battery current detection module, switch module, voltage conversion module, 485 isolation communication module, intrinsically safe isolation voltage regulator module and intrinsically safe current monitoring module. Among them, the MCU main control module is based on the ARM Cortex-M3 chip STM32F103C8T6.

[0042] According to the battery management communication protocol, the MCU completes the initial power-on process of the device by detecting the external isolated switch signal. The switch signal interface is connected to the switch button of the power supply device. When the button is turned on, a low-level signal is generated, which is converted into an isolated switch signal through an isolation optocoupler and connected to the detection IO port of the MCU. After the MCU detects the initial power-on switch signal, it controls the switch circuit to turn on and completes the initial power-on of the device.

[0043] The intrinsically safe lithium battery system for coal mines is connected to the 485 communication circuit through the serial port of the processor, and communicates with the control end of the power supply equipment to realize the on-off control of each power supply and the detection of the battery status. When the battery supplies power to the mounted equipment, the system detects the internal voltage of the entire intrinsically safe battery system and the real-time current of each output power supply in real time through the ARM Cortex-M3 chip STM32F103C8T6. These data are transmitted to the power-consuming equipment through the 485 communication protocol corresponding to the battery management system and the 485 isolation circuit.

[0044] At the same time, according to the 485 communication protocol between the battery system MCU controller and the power supply equipment, the single-chip microcomputer can respond in real time according to the needs of the power-consuming equipment. When the power-consuming equipment needs to shut down a certain power supply or perform an emergency stop operation, the system can respond in time. In addition, the intrinsically safe lithium battery system can detect the power consumption of the power-consuming equipment through hardware. When the power-consuming equipment cannot transmit the shutdown signal in time, the system can monitor the power output in real time according to the internal settings of the hardware, and automatically shut down the power supply under abnormal power consumption conditions.

[0045] The basic working process is as follows:

[0046] When the power supply equipment starts working, the external aviation plug is connected to the aviation plug interface of the corresponding power supply equipment in sequence, first connecting the signal end, and then the two power output ends. The intrinsically safe lithium battery system for coal mines detects whether the IO port pin generates an isolation switch signal through the ARM Cortex-M3 chip STM32F103C8T6, thereby controlling the intrinsically safe lithium battery system to initially power on the power-consuming equipment. The isolation switch signal is generated by short-circuiting two cores in the four-core signal end aviation plug. Therefore, the interface is connected to a switch button, and when the button is pressed, the circuit is short-circuited and generates a corresponding low-level signal. The signal is converted into an isolation signal through an optocoupler isolation circuit and connected to the corresponding detection IO port. After the microcontroller detects the isolation signal, it controls the power switch module to turn on and power the power-consuming equipment.

[0047] After the power switch module is turned on, the single-chip microcomputer controls the two power supplies of the switch module to ensure that the power supply is normal for the power supply equipment. At the same time, the single-chip microcomputer monitors the output and load status of the two power supplies in real time by detecting the analog signals output by the battery power detection module and the battery current detection module. The battery power detection module is used to detect the total power supply voltage at the output end of the battery. The internal algorithm of the system can convert the detected analog signal value into the real-time power supply voltage of the battery. The voltage is transmitted to the power-consuming equipment end through the 485 communication protocol to determine whether the intrinsically safe lithium battery system for coal mines needs to be charged. The battery current detection module is used to detect the output current of each power supply, monitor the power consumption of the load at the back end of each power supply in real time, and transmit it to the control end of the power-consuming equipment through the 485 communication protocol, so as to monitor and control the power output of the intrinsically safe lithium battery system for coal mines, and shut down the power supply in time according to the real-time data.

[0048] At the moment the switch module is turned on, the battery output supplies power to the electrical equipment through the intrinsically safe isolation voltage regulator module and the intrinsically safe current detection module. The output current of the intrinsically safe lithium battery pack outputs a 12V DC power supply through the intrinsically safe isolation voltage regulator module. The 12V DC power supply is combined with the LTC4380 surge chip to form an intrinsically safe current monitoring circuit. When abnormal power consumption of the electrical equipment is detected, the intrinsically safe current detection module can promptly shut down the power supply of the electrical equipment.

[0049] When the power-consuming equipment is working, it communicates with the battery system through the 485 isolation communication module to monitor the fluctuation of voltage and current in real time. According to the working requirements of the power supply equipment, the system can control the opening and closing of each power supply.

[0050] This intrinsically safe lithium battery system for coal mines can monitor the voltage and current of intrinsically safe equipment in real time, and cut off the power supply in time for protection when the power load is abnormal. According to the needs, the system can start and stop each power supply. This lithium battery system improves the safety and reliability of intrinsically safe power supply. The battery system is connected with a quick-connect aviation plug, which is quick and convenient to replace the power, creating a new power supply system.

[0051] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An intrinsically safe lithium battery system for coal mines, characterized in that: It includes MCU main control module, battery power detection module, current detection module, switch module, voltage conversion module, 485 isolation communication module, intrinsically safe isolation voltage regulator module, intrinsically safe current monitoring module, encapsulated battery box shell, intrinsically safe lithium battery pack, encapsulated colloid and external interface. According to the internal working process of the system, the output current of the intrinsically safe lithium battery pack first enters the voltage conversion module through the anti-reverse connection protection circuit and the current limiting protection circuit. The voltage conversion module outputs 3.3V and 5V DC power supplies respectively, of which the 3.3V DC power supply is used to power the MCU main control module and the 5V DC power supply is used to power the MCU main control module. The 485 isolation communication module is powered; the current then passes through the battery power detection module and the current detection module, which output analog quantities of corresponding detection signals to the MCU main control module according to internal algorithms for data processing, storage and external transmission; the current after passing through the detection module passes through the switch module, the intrinsically safe isolation voltage regulator module, the intrinsically safe current monitoring module and the external interface in sequence; the system is protected by a sealed battery box shell; when working, the external device communicates with the MCU main control module through the 485 isolation communication module to monitor the power consumption status of the equipment in real time.

2. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The MCU main control module controls the initialization output of the two power supply circuits by detecting the high and low levels of the IO port, monitors the battery voltage and each output current in real time through the analog-to-digital signal pin, and also transmits information to external devices that support the 485 communication protocol and controls the switch circuit.

3. An intrinsically safe lithium battery system for coal mines according to claim 1 or 2, characterized in that: The battery power detection module and the current detection module can respectively monitor the battery power and the magnitude of each current in real time, and output analog signals that comply with the protocol. The MCU main control microcontroller processes the output data.

4. An intrinsically safe lithium battery system for coal mines according to claim 1 or 2, characterized in that: The switch module adopts a two-stage field effect tube control circuit. The small voltage of the front stage controls the large voltage of the rear stage. The MUC microcontroller controls the start and stop of the switch module according to the received communication signal.

5. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The voltage conversion module consists of two paths. One path uses a low-power LDO power conversion chip to power the entire system. The other path uses an isolated power module to power the isolated external communication signal in accordance with the requirements of intrinsically safe equipment.

6. The intrinsically safe lithium battery system for coal mines according to claim 1 or 2, characterized in that: The 485 isolation communication module uses TTL serial port communication with the MCU main control module, and the TTL serial port signal and the communication chip control signal use optocouplers and microcontrollers to achieve signal isolation to ensure the stability and security of communication. The 485 isolation communication module can communicate with external devices that support the 485 communication protocol.

7. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The intrinsically safe isolated voltage regulator module adopts an isolated power supply voltage regulator module that meets the electrical intrinsic safety requirements to isolate the intrinsically safe power supply from the non-intrinsically safe power supply.

8. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The intrinsically safe current monitoring module uses the LTC4380 chip to combine a new intrinsically safe monitoring circuit to monitor the current in real time and then control the power supply output energy.

9. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The shell of the encapsulated battery box is made of 304 stainless steel. The front end is protruded with an aviation plug connected to the power supply equipment, the rear end is designed with a change handle, and the colloid filled inside the encapsulated colloid is epoxy resin colloid. The external connectors are three aviation plugs, one is a four-core socket for 485 communication signal and switch signal detection, and the other two are power output interfaces. The aviation plugs are isolated from the internal system. The system contains an independent charging interface, a DC_05 interface insulated from the shell, and all interfaces have independent rubber plugs on the outside.

10. An intrinsically safe lithium battery system for coal mines according to claim 1, characterized in that: The intrinsically safe lithium battery pack comprises intrinsically safe lithium battery cells, which are connected in a three-series and two-parallel manner, and the battery is provided with a charge and discharge protection circuit for a single intrinsically safe lithium battery cell.

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