Coal mine power supply management system with multiple protection functions

Abstract

The invention discloses a coal mine power management system with multiple protection functions, and the system is characterized in that an AC input protection circuit is electrically connected with AC input through an AC / DC circuit, and is used for cutting off a corresponding loop when detecting that DC output by the AC / DC circuit has overvoltage, undervoltage or overcurrent; the battery management protection circuit cuts off a corresponding loop when detecting that the battery pack is under-voltage, over-voltage, over-current or over-high in temperature; the battery charging management circuit cuts off a charging loop of the battery pack when an abnormal condition is detected; the battery discharge management circuit cuts off a discharge loop of the battery pack when an abnormal condition is detected; the battery output control circuit is used for cutting off the output loop when there is AC input and switching on the output loop when there is no AC input. The coal mine power management system has multiple protection functions, even if one stage of protection circuit breaks down, other stages of protection circuits can guarantee reliable operation of the power management system, and therefore the reliability and safety of the coal mine power management system are improved.

Description

Technical Field

[0001] The invention relates to the technical field of mine power supply, and in particular to a coal mine power supply management system with multiple protection functions. Background Art

[0002] With the development of the coal mining industry, the safety requirements for the power supply of coal mine underground equipment are getting higher and higher; at the same time, the national regulatory authorities have increasingly strict management requirements for the coal mining industry. According to relevant policies and regulations, coal mine underground equipment should have a backup power supply function, and should be able to continue to work for a period of time through the backup power supply after the AC power supply is cut off. At present, most coal mine underground equipment uses lithium batteries as a backup power supply. However, lithium batteries themselves are unsafe devices. In the event of overcharge, over-discharge, overvoltage, overtemperature, etc., they are prone to bulging, short circuit, damage, spontaneous combustion and other dangerous situations, which can easily cause gas explosions in coal mines, posing a serious threat to the lives and property of coal miners and coal mining enterprises. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide a power management system for coal mines with multiple protection functions, wherein even if one level of protection circuit fails, other levels of protection circuits can ensure the reliable operation of the power management system, thereby improving the reliability and safety of the coal mine power management system.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: A power management system for coal mines with multiple protection functions, including an AC input protection circuit, a battery management protection circuit, a battery charging management circuit, a battery discharging management circuit and a battery output control circuit; The AC input protection circuit is electrically connected to the AC input through the AC / DC circuit, and is used to protect the DC power converted by the AC / DC circuit from overvoltage, undervoltage and overcurrent, and cut off the corresponding circuit when it is detected that the DC power output by the AC / DC circuit has overvoltage, undervoltage or overcurrent; The battery management protection circuit is electrically connected to the battery pack and is used to perform undervoltage protection, overvoltage protection, overcurrent protection, temperature protection, and balancing of each battery in the battery pack, and cut off the corresponding circuit when it is detected that the battery pack has undervoltage, overvoltage, overcurrent or high temperature; The battery charging management circuit is connected to the charging circuit of the battery pack and is used to detect abnormal conditions on the charging circuit of the battery pack and cut off the charging circuit of the battery pack when an abnormal condition is detected; The battery discharge management circuit is connected to the discharge circuit of the battery pack and is used to detect abnormal conditions on the discharge circuit of the battery pack and cut off the discharge circuit of the battery pack when an abnormal condition is detected; The battery output control circuit is connected to the output circuit of the battery pack, and is used to cut off the output circuit when there is an AC input, and to connect the output circuit when there is no AC input.

[0005] In this way, the AC input protection circuit is used to cut off the corresponding circuit when overvoltage, undervoltage and overcurrent appear in the AC input, so as to protect the subsequent circuit. The battery management protection circuit is used to protect the subsequent circuit when undervoltage, overvoltage, overcurrent, overtemperature, and imbalance of batteries in the battery pack appear in the battery pack, so as to ensure the safe and efficient operation of the battery pack. At the same time, the battery charging management circuit further cuts off the charging circuit of the battery pack when charging is abnormal. The battery charging management circuit and the battery management protection circuit can simultaneously realize protection against abnormal charging, so that when an abnormality occurs in the first-level charging protection circuit, the other-level charging protection circuit The circuit can still achieve the protection effect of abnormal charging. Similarly, the battery discharge management circuit further cuts off the discharge circuit of the battery pack when the discharge is abnormal. The battery discharge management circuit and the battery management protection circuit can simultaneously achieve the protection of abnormal discharge. When the first-level discharge protection circuit is abnormal, the other-level discharge protection circuit can still achieve the protection effect of abnormal discharge. The battery output control circuit can ensure that the external output of the battery pack is cut off when the AC input is on, thereby extending the service life of the battery pack. At the same time, the external output of the battery pack is controlled when the AC input is disconnected to realize the function of backup power supply. Therefore, this solution improves the reliability and safety of the power management system for coal mines by designing multiple protection functions.

[0006] Preferably, it also includes a microcontroller and a display screen, the input end of the microcontroller is electrically connected to the battery management and protection circuit, the output end of the microcontroller U6 is electrically connected to the display screen, the microcontroller obtains key parameters of the battery pack through the battery management and protection circuit and sends them to the display screen for display, and can adjust relevant parameters of the battery management and protection circuit.

[0007] In this way, the microcontroller obtains the key parameters of the battery pack such as voltage, current and temperature through the battery management protection circuit and displays the relevant parameters on the display screen, which is convenient for maintenance personnel to grasp the relevant information of the battery pack in a timely manner. At the same time, the charging current, charging voltage, protection voltage, protection current and other related parameters of the battery management protection circuit can be adjusted in time through programming according to the key parameters of the battery pack read, thereby realizing intelligent charging and discharging management of the battery pack.

[0008] Preferably, the AC input protection circuit includes an AC input protection controller, a first overvoltage detection component, a first undervoltage detection component, a current detection resistor R5 and an NMOS tube Q1; The first undervoltage detection component includes a resistor R1 and a resistor R3, one end of the resistor R1 is connected to one end of the resistor R3, the other end of the resistor R1 is connected to the positive output end of the AC / DC circuit, the other end of the resistor R3 is connected to the negative output end of the AC / DC circuit, and the undervoltage detection input end of the AC input protection controller is connected between the resistor R1 and the resistor R3; The first overvoltage detection component includes a resistor R2 and a resistor R4, one end of the resistor R2 is connected to one end of the resistor R4, the other end of the resistor R2 is connected to the positive output end of the AC / DC circuit, the other end of the resistor R4 is connected to the negative output end of the AC / DC circuit, and the overvoltage detection input end of the AC input protection controller is connected between the resistor R2 and the resistor R4; One end of the current detection resistor R5 is connected to the positive output end of the AC / DC circuit, the other end of the current detection resistor R5 is connected to the source of the NMOS tube Q1, the two overcurrent detection input ends of the AC input protection controller are respectively connected to the two ends of the current detection resistor R5, and the output end of the AC input protection controller is connected to the gate of the NMOS tube Q1.

[0009] In this way, the AC input AC / DC circuit converts the AC voltage into a DC voltage output, and then the AC input protection controller performs overvoltage, undervoltage, and overcurrent protection on the output DC power supply. Undervoltage detection is performed by voltage division by resistors R1 and R3, overvoltage detection is performed by voltage division by resistors R2 and R4, and overcurrent detection is performed by current detection resistor R5. When the AC input protection controller detects an overvoltage, undervoltage, or overcurrent event, it controls the NMOS tube Q1 to turn off, thereby shutting down the power supply to the subsequent circuit.

[0010] Preferably, the battery management protection circuit includes a battery management protection controller, a temperature control switch RS1, an NMOS tube Q5, an NMOS tube Q6 and a current detection resistor R11; One end of the temperature control switch RS1 is connected to the positive output end of the battery pack, and the other end of the temperature control switch RS1 is connected to the source of the NMOS tube Q6. The temperature control switch RS1 is automatically disconnected when the temperature of the battery pack exceeds a set value. The drain of the NMOS tube Q6 is connected to the source of the NMOS tube Q5. The drain of the NMOS tube Q5 is connected to the charging circuit and the discharging circuit of the battery pack at the same time. The current detection resistor R11 is connected to the negative output end of the battery pack; The two overcurrent detection input terminals of the battery management and protection controller are respectively connected to the two ends of the current detection resistor R11. When the battery pack is charging, the battery management and protection controller turns off the NMOS tube Q6 when it detects that the current of the current detection resistor R11 exceeds the charging current setting value. When the battery pack is discharging, the battery management and protection controller turns off the NMOS tube Q5 when it detects that the current of the current detection resistor R11 exceeds the discharge current setting value.

[0011] In this way, the battery management and protection controller implements multiple protection functions for the battery pack formed by multiple lithium batteries, including undervoltage protection, overvoltage protection, overcurrent protection, temperature protection, equalization processing, etc. At the same time, the microcontroller can also monitor the key parameters of the battery pack such as voltage, current and temperature through the battery management and protection controller to ensure the safe and efficient operation of the battery pack. The temperature control switch RS1 detects the temperature of the battery pack. When the temperature control switch RS1 detects that the temperature of the battery pack is too high, it automatically disconnects and the battery pack no longer outputs to the outside; the current detection resistor R11 performs bidirectional current detection. When the current detection resistor R11 detects charging overcurrent, the battery management and protection controller turns off the NMOS tube Q6; when the current detection resistor R11 detects discharging overcurrent, the battery management and protection controller turns off the NMOS tube Q5.

[0012] Preferably, the battery charging management circuit includes a battery charging management module and a PMOS tube Q3, one end of the battery charging management module is connected to the drain of the NMOS tube Q1, the other end of the battery charging management module is connected to the source of the PMOS tube Q3, the drain of the PMOS tube Q3 is connected to the drain of the NMOS tube Q5, and the gate of the PMOS tube Q3 is electrically connected to the microcontroller. The microcontroller detects the charging status of the battery pack according to the key parameters of the battery pack obtained from the battery management protection circuit, and disconnects the PMOS tube Q3 when an abnormal situation is detected.

[0013] In this way, this solution designs a first-level independent battery charging management circuit composed of a battery charging management module, a PMOS tube Q3, and a microcontroller. When the microcontroller detects that the battery pack is fully charged or an abnormal situation occurs, it can control the PMOS tube Q3 to shut down the charging circuit of the battery pack; thereby realizing multi-level charging protection by the battery management protection circuit and the battery charging management circuit. Even if one of the first-level charging protection circuits fails, the other-level charging protection circuit can still play a protective role.

[0014] Preferably, the battery discharge management circuit includes a battery discharge protection controller, a second overvoltage detection component, a second undervoltage detection component, a current detection resistor R6 and an NMOS tube Q4; The second undervoltage detection component includes a resistor R8 and a resistor R10, one end of the resistor R8 is connected to one end of the resistor R10, the other end of the resistor R8 is connected to the drain of the NMOS tube Q5, the other end of the resistor R10 is connected to the current detection resistor R11, and the undervoltage detection input end of the battery discharge protection controller is connected between the resistor R8 and the resistor R10; The second overvoltage detection component includes a resistor R7 and a resistor R9, one end of the resistor R7 is connected to one end of the resistor R9, the other end of the resistor R7 is connected to the drain of the NMOS tube Q5, the other end of the resistor R9 is connected to the current detection resistor R11, and the overvoltage detection input end of the battery discharge protection controller is connected between the resistor R7 and the resistor R9; One end of the current detection resistor R6 is connected to the drain of the NMOS tube Q5, and the other end of the current detection resistor R6 is connected to the source of the NMOS tube Q4. The two overcurrent detection input ends of the battery discharge protection controller are respectively connected to the two ends of the current detection resistor R6, and the output end of the battery discharge protection controller is connected to the gate of the NMOS tube Q4.

[0015] In this way, this solution designs a first-level independent battery discharge management circuit composed of a battery discharge protection controller, a second overvoltage detection component, a second undervoltage detection component, a current detection resistor R6 and an NMOS tube Q4, which can protect the battery pack from overvoltage, undervoltage and overcurrent during discharge. Undervoltage detection is performed by voltage division by resistors R8 and R10, overvoltage detection is performed by voltage division by resistors R7 and R9, and overcurrent detection is performed by current detection resistor R6. When the battery discharge protection controller detects the occurrence of overvoltage, undervoltage and overcurrent events, it controls the NMOS tube Q4 to turn off, thereby closing the discharge circuit of the battery pack. Therefore, this solution realizes multi-level discharge protection composed of a battery management protection circuit and a battery discharge management circuit. Even if one of the first-level discharge protection circuits fails, the other-level discharge protection circuit can still play a protective role.

[0016] Preferably, the battery output control circuit comprises an NMOS tube Q2, a voltage comparator and a high-side switch, the input end of the voltage comparator is connected to the drain of the NMOS tube Q1, and is used to detect whether there is an AC input, the output end of the voltage comparator is connected to the input end of the high-side switch, the output end of the high-side switch is connected to the gate of the NMOS tube Q2, the source of the NMOS tube Q2 is connected to the drain of the NMOS tube Q4, and the drain of the NMOS tube Q2 is connected to the output end of the system; The voltage comparator sends a first control signal to the high-side switch when an AC input signal is detected, and the high-side switch turns on the NMOS tube Q2. The voltage comparator sends a second control signal to the high-side switch when no AC input signal is detected, and the high-side switch turns off the NMOS tube Q2.

[0017] In this way, this solution designs a battery output control circuit composed of a voltage comparator, a high-side switch, and an NMOS tube Q2. When the system detects that the AC input is connected, the voltage comparator sends a first control signal to the high-side switch, and the NMOS tube Q2 is turned off through the high-side switch, thereby turning off the external output of the battery pack and extending the service life of the battery pack. When the system detects that the AC input is disconnected, the voltage comparator sends a second control signal to the high-side switch, and the NMOS tube Q2 is turned on through the high-side switch, thereby turning on the external output of the battery pack and realizing the backup power supply function.

[0018] Compared with the prior art, the present invention has the following advantages: 1. In order to improve the reliability of the coal mine power management system, the present invention has multiple overvoltage, undervoltage, overcurrent, overtemperature and over-discharge protection functions. Even if one level of protection circuit fails, other levels of protection circuits can ensure the reliable operation of the power management system, thereby improving the reliability and safety of the coal mine power management system.

[0019] 2. The present invention has the functions of intelligent charge and discharge management of battery packs and monitoring and displaying battery pack status information, which is convenient for maintenance personnel to grasp relevant information of the battery pack in time; the system adopts high-power separation devices to meet the requirements of component selection for safety standards certification in the coal mining industry.

[0020] 3. The present invention provides good protection for the safe use of power supplies and batteries of coal mine equipment, can effectively improve the safety performance of coal mine power supplies, and reduce the occurrence of coal mine safety accidents caused by power supply anomalies. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Attached Figure 1 The system block diagram of the power management system for coal mines with multiple protection functions of the present invention. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0023] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] As attached Figure 1 As shown, a power management system for coal mines with multiple protection functions includes an AC input protection circuit, a battery management protection circuit, a battery charging management circuit, a battery discharge management circuit, a battery output control circuit, a microcontroller and a display screen.

[0025] Specifically, the AC input protection circuit is electrically connected to the AC input through the AC / DC circuit U1, and is used to protect the DC power converted by the AC input through the AC / DC circuit U1 from overvoltage, undervoltage and overcurrent, and cut off the corresponding circuit when it is detected that the DC power output by the AC / DC circuit U1 has overvoltage, undervoltage or overcurrent.

[0026] In this specific embodiment, the AC input protection circuit includes an AC input protection controller U2, a first overvoltage detection component, a first undervoltage detection component, a current detection resistor R5 and an NMOS tube Q1; in this specific embodiment, the AC input protection controller U2 adopts LM5069, the first undervoltage detection component includes a resistor R1 and a resistor R3, one end of the resistor R1 is connected to one end of the resistor R3, the other end of the resistor R1 is connected to the positive output end of the AC / DC circuit U1, the other end of the resistor R3 is connected to the negative output end of the AC / DC circuit U1, and the undervoltage detection input end of the AC input protection controller U2 is connected between the resistor R1 and the resistor R3; the first overvoltage detection component includes a resistor R2 and resistor R4, one end of the resistor R2 is connected to one end of the resistor R4, the other end of the resistor R2 is connected to the positive output end of the AC / DC circuit U1, the other end of the resistor R4 is connected to the negative output end of the AC / DC circuit U1, and the overvoltage detection input end of the AC input protection controller U2 is connected between the resistor R2 and the resistor R4; one end of the current detection resistor R5 is connected to the positive output end of the AC / DC circuit U1, the other end of the current detection resistor R5 is connected to the source of the NMOS tube Q1, the two overcurrent detection input ends of the AC input protection controller U2 are respectively connected to the two ends of the current detection resistor R5, and the output end of the AC input protection controller U2 is connected to the gate of the NMOS tube Q1.

[0027] In this way, the AC input AC / DC circuit U1 converts the AC input into a DC voltage output, and then the output DC power supply is protected against overvoltage, undervoltage, and overcurrent through the AC input protection controller U2. Undervoltage detection is performed by voltage division by resistors R1 and R3, overvoltage detection is performed by voltage division by resistors R2 and R4, and overcurrent detection is performed by current detection resistor R5. When the AC input protection controller U2 detects an overvoltage, undervoltage, or overcurrent event, it controls the NMOS tube Q1 to turn off, thereby shutting down the power supply to the subsequent circuit.

[0028] Specifically, the battery management protection circuit is electrically connected to the battery pack and is used to perform undervoltage protection, overvoltage protection, overcurrent protection, temperature protection, and balancing of each battery in the battery pack, and cut off the corresponding circuit when undervoltage, overvoltage, overcurrent or high temperature is detected in the battery pack.

[0029] In this specific embodiment, the battery management and protection circuit includes a battery management and protection controller U8, a temperature control switch RS1, an NMOS tube Q5, an NMOS tube Q6 and a current detection resistor R11; in this specific embodiment, the battery management and protection controller U8 adopts BQ76952.

[0030] One end of the temperature control switch RS1 is connected to the positive output end of the battery pack, and the other end of the temperature control switch RS1 is connected to the source of the NMOS tube Q6. The temperature control switch RS1 is automatically disconnected when the temperature of the battery pack exceeds the set value. The drain of the NMOS tube Q6 is connected to the source of the NMOS tube Q5. The drain of the NMOS tube Q5 is connected to the charging circuit and the discharging circuit of the battery pack at the same time. The current detection resistor R11 is connected to the negative output end of the battery pack; The two overcurrent detection input terminals of the battery management and protection controller U8 are respectively connected to the two ends of the current detection resistor R11. When the battery pack is charging, the battery management and protection controller U8 turns off the NMOS tube Q6 when it detects that the current of the current detection resistor R11 exceeds the charging current setting value. When the battery pack is discharging, the battery management and protection controller U8 turns off the NMOS tube Q5 when it detects that the current of the current detection resistor R11 exceeds the discharge current setting value.

[0031] In this way, the battery management and protection controller U8 implements multiple protection functions for the battery pack formed by multiple lithium batteries, including undervoltage protection, overvoltage protection, overcurrent protection, temperature protection, and balancing processing; at the same time, the microcontroller U6 can also monitor the key parameters of the battery pack such as voltage, current, and temperature through the battery management and protection controller U8 to ensure the safe and efficient operation of the battery pack. The temperature control switch RS1 detects the temperature of the battery pack. When the temperature control switch RS1 detects that the temperature of the battery pack is too high, it automatically disconnects and the battery pack no longer outputs to the outside; the current detection resistor R11 performs bidirectional current detection. When the current detection resistor R11 detects charging overcurrent, the battery management and protection controller U8 turns off the NMOS tube Q6; when the current detection resistor R11 detects discharging overcurrent, the battery management and protection controller U8 turns off the NMOS tube Q5.

[0032] Specifically, the battery charging management circuit is connected to the charging circuit of the battery pack, and is used to detect abnormal conditions on the charging circuit of the battery pack, and cut off the charging circuit of the battery pack when an abnormal condition is detected.

[0033] In this specific embodiment, the battery charging management circuit includes a battery charging management module U3 and a PMOS tube Q3. One end of the battery charging management module U3 is connected to the drain of the NMOS tube Q1, and the other end of the battery charging management module U3 is connected to the source of the PMOS tube Q3. The drain of the PMOS tube Q3 is connected to the drain of the NMOS tube Q5. The gate of the PMOS tube Q3 is electrically connected to the microcontroller U6. The microcontroller U6 detects the charging status of the battery pack according to the key parameters of the battery pack obtained from the battery management protection circuit, and disconnects the PMOS tube Q3 when an abnormal situation is detected.

[0034] In this way, this solution designs a first-level independent battery charging management circuit composed of a battery charging management module U3, a PMOS tube Q3, and a microcontroller U6. When the microcontroller U6 detects that the battery pack is fully charged or an abnormal situation occurs, it can control the PMOS tube Q3 to shut down the charging circuit of the battery pack; thereby realizing multi-level charging protection by the battery management protection circuit and the battery charging management circuit. Even if one of the first-level charging protection circuits fails, the other-level charging protection circuit can still play a protective role.

[0035] Specifically, the battery discharge management circuit is connected to the discharge circuit of the battery pack, and is used to detect abnormal conditions on the discharge circuit of the battery pack, and cut off the discharge circuit of the battery pack when an abnormal condition is detected.

[0036] In this embodiment, the battery discharge management circuit includes a battery discharge protection controller U7, a second overvoltage detection component, a second undervoltage detection component, a current detection resistor R6 and an NMOS tube Q4; the battery discharge protection controller U7 adopts LM5069.

[0037] The second undervoltage detection component includes a resistor R8 and a resistor R10, one end of the resistor R8 is connected to one end of the resistor R10, the other end of the resistor R8 is connected to the drain of the NMOS tube Q5, the other end of the resistor R10 is connected to the current detection resistor R11, and the undervoltage detection input end of the battery discharge protection controller U7 is connected between the resistor R8 and the resistor R10; The second overvoltage detection component includes a resistor R7 and a resistor R9, one end of the resistor R7 is connected to one end of the resistor R9, the other end of the resistor R7 is connected to the drain of the NMOS tube Q5, the other end of the resistor R9 is connected to the current detection resistor R11, and the overvoltage detection input end of the battery discharge protection controller U7 is connected between the resistor R7 and the resistor R9; One end of the current detection resistor R6 is connected to the drain of the NMOS tube Q5, and the other end of the current detection resistor R6 is connected to the source of the NMOS tube Q4. The two overcurrent detection input ends of the battery discharge protection controller U7 are respectively connected to the two ends of the current detection resistor R6, and the output end of the battery discharge protection controller U7 is connected to the gate of the NMOS tube Q4.

[0038] In this way, this solution designs a first-level independent battery discharge management circuit composed of a battery discharge protection controller U7, a second overvoltage detection component, a second undervoltage detection component, a current detection resistor R6 and an NMOS tube Q4, which can protect the battery pack from overvoltage, undervoltage and overcurrent during discharge. Undervoltage detection is performed by voltage division by resistors R8 and R10, overvoltage detection is performed by voltage division by resistors R7 and R9, and overcurrent detection is performed by current detection resistor R6. When the battery discharge protection controller detects the occurrence of overvoltage, undervoltage and overcurrent events, it controls the NMOS tube Q4 to turn off, thereby closing the discharge circuit of the battery pack. Therefore, this solution realizes multi-level discharge protection composed of a battery management protection circuit and a battery discharge management circuit. Even if one of the first-level discharge protection circuits fails, the other-level discharge protection circuit can still play a protective role.

[0039] Specifically, the battery output control circuit is connected to the output circuit of the battery pack, and is used to cut off the output circuit when there is an AC input, and to connect the output circuit when there is no AC input.

[0040] In this specific embodiment, the battery output control circuit includes an NMOS tube Q2, a voltage comparator U5 and a high-side switch U4. The input end of the voltage comparator U5 is connected to the drain of the NMOS tube Q1 to detect whether there is an AC input. The output end of the voltage comparator U5 is connected to the input end of the high-side switch U4. The output end of the high-side switch U4 is connected to the gate of the NMOS tube Q2. The source of the NMOS tube Q2 is connected to the drain of the NMOS tube Q4. The drain of the NMOS tube Q2 is connected to the output end of the system. The voltage comparator U5 sends a first control signal to the high-side switch U4 when an AC input signal is detected, and the high-side switch U4 turns on the NMOS tube Q2. The voltage comparator U5 sends a second control signal to the high-side switch U4 when no AC input signal is detected, and the high-side switch U4 turns off the NMOS tube Q2.

[0041] In this way, this solution designs a battery output control circuit composed of a voltage comparator U5, a high-side switch U4, and an NMOS tube Q2. When the system detects that the AC input is connected, the voltage comparator U5 sends a first control signal to the high-side switch U4, and the NMOS tube Q2 is turned off by the high-side switch U4, thereby turning off the external output of the battery pack and extending the service life of the battery pack. When the system detects that the AC input is disconnected, the voltage comparator U5 sends a second control signal to the high-side switch U4, and the NMOS tube Q2 is turned on by the high-side switch U4, thereby turning on the external output of the battery pack and realizing the backup power supply function.

[0042] Specifically, the input end of the microcontroller U6 is electrically connected to the battery management and protection circuit, and the output end of the microcontroller U6 is electrically connected to the display screen U9. The microcontroller U6 obtains the key parameters of the battery pack through the battery management and protection circuit and sends them to the display screen U9 for display, and can adjust the relevant parameters of the battery management and protection circuit.

[0043] In this way, the microcontroller U6 obtains the key parameters of the battery pack such as voltage, current and temperature through the battery management protection circuit and displays the relevant parameters through the display screen U9, which is convenient for maintenance personnel to grasp the relevant information of the battery pack in a timely manner. At the same time, the charging current, charging voltage, protection voltage, protection current and other related parameters of the battery management protection circuit can be adjusted in time through programming according to the key parameters of the battery pack read, thereby realizing intelligent charging and discharging management of the battery pack.

[0044] In this way, the AC input protection circuit is used to cut off the corresponding circuit when overvoltage, undervoltage and overcurrent appear in the AC input, so as to protect the subsequent circuit. The battery management protection circuit is used to protect the subsequent circuit when undervoltage, overvoltage, overcurrent, overtemperature, and imbalance of batteries in the battery pack appear in the battery pack, so as to ensure the safe and efficient operation of the battery pack. At the same time, the battery charging management circuit further cuts off the charging circuit of the battery pack when charging is abnormal. The battery charging management circuit and the battery management protection circuit can simultaneously realize protection against abnormal charging, so that when an abnormality occurs in the first-level charging protection circuit, the other-level charging protection circuit The circuit can still achieve the protection effect of abnormal charging. Similarly, the battery discharge management circuit further cuts off the discharge circuit of the battery pack when the discharge is abnormal. The battery discharge management circuit and the battery management protection circuit can simultaneously achieve the protection of abnormal discharge. When the first-level discharge protection circuit is abnormal, the other-level discharge protection circuit can still achieve the protection effect of abnormal discharge. The battery output control circuit can ensure that the external output of the battery pack is cut off when the AC input is on, thereby extending the service life of the battery pack. At the same time, the external output of the battery pack is controlled when the AC input is disconnected to realize the function of backup power supply. Therefore, this solution improves the reliability and safety of the power management system for coal mines by designing multiple protection functions.

[0045] Compared with the prior art, in order to improve the reliability of the coal mine power management system, the present invention has multiple overvoltage, undervoltage, overcurrent, overtemperature, and over-discharge protection functions. Even if one of the first-level protection circuits fails, the other-level protection circuits can ensure the reliable operation of the power management system, thereby improving the reliability and safety of the coal mine power management system. The present invention has intelligent charging and discharging management of the battery pack and battery pack status information monitoring and display functions, which are convenient for maintenance personnel to grasp the relevant information of the battery pack in time; the system adopts high-power separation devices to meet the coal mine industry safety standard certification requirements for component selection. The present invention provides good protection for the safe use of power supplies and batteries for coal mine equipment, can effectively improve the safety performance of coal mine power supplies, and reduce the occurrence of coal mine safety accidents caused by power supply anomalies.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. A power management system for coal mines with multiple protection functions, characterized in that: Including AC input protection circuit, battery management protection circuit, battery charging management circuit, battery discharge management circuit and battery output control circuit; The AC input protection circuit is electrically connected to the AC input through the AC / DC circuit, and is used to protect the DC power converted by the AC / DC circuit from overvoltage, undervoltage and overcurrent, and cut off the corresponding circuit when it is detected that the DC power output by the AC / DC circuit has overvoltage, undervoltage or overcurrent; The battery management protection circuit is electrically connected to the battery pack and is used to perform undervoltage protection, overvoltage protection, overcurrent protection, temperature protection, and balancing of each battery in the battery pack, and cut off the corresponding circuit when it is detected that the battery pack has undervoltage, overvoltage, overcurrent or high temperature; The battery charging management circuit is connected to the charging circuit of the battery pack and is used to detect abnormal conditions on the charging circuit of the battery pack and cut off the charging circuit of the battery pack when an abnormal condition is detected; The battery discharge management circuit is connected to the discharge circuit of the battery pack and is used to detect abnormal conditions on the discharge circuit of the battery pack and cut off the discharge circuit of the battery pack when an abnormal condition is detected; The battery output control circuit is connected to the output circuit of the battery pack, and is used to cut off the output circuit when there is an AC input, and to connect the output circuit when there is no AC input.

2. The power management system for coal mines with multiple protection functions according to claim 1, characterized in that: It also includes a microcontroller and a display screen. The input end of the microcontroller is electrically connected to the battery management and protection circuit, and the output end of the microcontroller U6 is electrically connected to the display screen. The microcontroller obtains key parameters of the battery pack through the battery management and protection circuit and sends them to the display screen for display, and can adjust relevant parameters of the battery management and protection circuit.

3. The coal mine power management system with multiple protection functions according to claim 2 is characterized in that: The AC input protection circuit includes an AC input protection controller, a first overvoltage detection component, a first undervoltage detection component, a current detection resistor R5 and an NMOS tube Q1; The first undervoltage detection component includes a resistor R1 and a resistor R3, one end of the resistor R1 is connected to one end of the resistor R3, the other end of the resistor R1 is connected to the positive output end of the AC / DC circuit, the other end of the resistor R3 is connected to the negative output end of the AC / DC circuit, and the undervoltage detection input end of the AC input protection controller is connected between the resistor R1 and the resistor R3; The first overvoltage detection component includes a resistor R2 and a resistor R4, one end of the resistor R2 is connected to one end of the resistor R4, the other end of the resistor R2 is connected to the positive output end of the AC / DC circuit, the other end of the resistor R4 is connected to the negative output end of the AC / DC circuit, and the overvoltage detection input end of the AC input protection controller is connected between the resistor R2 and the resistor R4; One end of the current detection resistor R5 is connected to the positive output end of the AC / DC circuit, the other end of the current detection resistor R5 is connected to the source of the NMOS tube Q1, the two overcurrent detection input ends of the AC input protection controller are respectively connected to the two ends of the current detection resistor R5, and the output end of the AC input protection controller is connected to the gate of the NMOS tube Q1.

4. The power management system for coal mines with multiple protection functions according to claim 3 is characterized in that: The battery management protection circuit includes a battery management protection controller, a temperature control switch RS1, an NMOS tube Q5, an NMOS tube Q6 and a current detection resistor R11; One end of the temperature control switch RS1 is connected to the positive output end of the battery pack, and the other end of the temperature control switch RS1 is connected to the source of the NMOS tube Q6. The temperature control switch RS1 is automatically disconnected when the temperature of the battery pack exceeds a set value. The drain of the NMOS tube Q6 is connected to the source of the NMOS tube Q5. The drain of the NMOS tube Q5 is connected to the charging circuit and the discharging circuit of the battery pack at the same time. The current detection resistor R11 is connected to the negative output end of the battery pack; The two overcurrent detection input terminals of the battery management and protection controller are respectively connected to the two ends of the current detection resistor R11. When the battery pack is charging, the battery management and protection controller turns off the NMOS tube Q6 when it detects that the current of the current detection resistor R11 exceeds the charging current setting value. When the battery pack is discharging, the battery management and protection controller turns off the NMOS tube Q5 when it detects that the current of the current detection resistor R11 exceeds the discharge current setting value.

5. The power management system for coal mines with multiple protection functions according to claim 4, characterized in that: The battery charging management circuit includes a battery charging management module and a PMOS tube Q3, one end of the battery charging management module is connected to the drain of the NMOS tube Q1, the other end of the battery charging management module is connected to the source of the PMOS tube Q3, the drain of the PMOS tube Q3 is connected to the drain of the NMOS tube Q5, and the gate of the PMOS tube Q3 is electrically connected to the microcontroller. The microcontroller detects the charging status of the battery pack according to the key parameters of the battery pack obtained from the battery management protection circuit, and disconnects the PMOS tube Q3 when an abnormal situation is detected.

6. The power management system for coal mines with multiple protection functions according to claim 5, characterized in that: The battery discharge management circuit includes a battery discharge protection controller, a second overvoltage detection component, a second undervoltage detection component, a current detection resistor R6 and an NMOS tube Q4; The second undervoltage detection component includes a resistor R8 and a resistor R10, one end of the resistor R8 is connected to one end of the resistor R10, the other end of the resistor R8 is connected to the drain of the NMOS tube Q5, the other end of the resistor R10 is connected to the current detection resistor R11, and the undervoltage detection input end of the battery discharge protection controller is connected between the resistor R8 and the resistor R10; The second overvoltage detection component includes a resistor R7 and a resistor R9, one end of the resistor R7 is connected to one end of the resistor R9, the other end of the resistor R7 is connected to the drain of the NMOS tube Q5, the other end of the resistor R9 is connected to the current detection resistor R11, and the overvoltage detection input end of the battery discharge protection controller is connected between the resistor R7 and the resistor R9; One end of the current detection resistor R6 is connected to the drain of the NMOS tube Q5, and the other end of the current detection resistor R6 is connected to the source of the NMOS tube Q4. The two overcurrent detection input ends of the battery discharge protection controller are respectively connected to the two ends of the current detection resistor R6, and the output end of the battery discharge protection controller is connected to the gate of the NMOS tube Q4.

7. The power management system for coal mines with multiple protection functions according to claim 6, characterized in that: The battery output control circuit includes an NMOS tube Q2, a voltage comparator and a high-side switch, wherein the input end of the voltage comparator is connected to the drain of the NMOS tube Q1 to detect whether there is an AC input, the output end of the voltage comparator is connected to the input end of the high-side switch, the output end of the high-side switch is connected to the gate of the NMOS tube Q2, the source of the NMOS tube Q2 is connected to the drain of the NMOS tube Q4, and the drain of the NMOS tube Q2 is connected to the output end of the system; The voltage comparator sends a first control signal to the high-side switch when an AC input signal is detected, and the high-side switch turns on the NMOS tube Q2. The voltage comparator sends a second control signal to the high-side switch when no AC input signal is detected, and the high-side switch turns off the NMOS tube Q2.

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