CN111439164A - New energy automobile lithium battery charging and discharging protection circuit and controllable voltage source adjusting method - Google Patents

New energy automobile lithium battery charging and discharging protection circuit and controllable voltage source adjusting method Download PDF

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Publication number
CN111439164A
CN111439164A CN202010243823.2A CN202010243823A CN111439164A CN 111439164 A CN111439164 A CN 111439164A CN 202010243823 A CN202010243823 A CN 202010243823A CN 111439164 A CN111439164 A CN 111439164A
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resistor
capacitor
voltage
pin
triode
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CN202010243823.2A
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Chinese (zh)
Inventor
蒋勇
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Nanjing Arp New Energy Technology Co ltd
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Nanjing Arp New Energy Technology Co ltd
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Priority to CN202010243823.2A priority Critical patent/CN111439164A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
    • B60L58/15—Preventing overcharging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
    • B60L58/14—Preventing excessive discharging
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/0031—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits using battery or load disconnect circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/547—Voltage
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/549—Current
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

The invention discloses a new energy automobile lithium battery charging and discharging protection circuit and a controllable voltage source adjusting method, wherein the method comprises the following steps: the over-charge protection module comprises an over-charge protection module, a voltage control module, an over-current operation module, a discharge protection module and an over-discharge regulation module, wherein a triode Q3 in the over-charge protection module obtains a feedback voltage value of the voltage control module through a base electrode terminal, so that an emitter terminal is conducted to block an over-charge voltage from passing through; a transistor Q6 in the voltage control module is used as a non-contact switch to transmit the control ground voltage to the overcurrent operation module; the operational amplifier U2 in the overcurrent operation module is started by comparing the set ground current parameter with the received current, and the capacitor C4 provides the storage voltage for the operational amplifier U2 to improve the operation speed; the diode D7 in the discharge protection module is used for unidirectional output of voltage to prevent reverse transmission of voltage during discharge; capacitor C8 is used for the insufficient current of lithium cell B1 when overdischarging in the regulation module of overdischarging, and then provides the storage voltage and reduces the discharge apparatus damage.

Description

New energy automobile lithium battery charging and discharging protection circuit and controllable voltage source adjusting method
Technical Field
The invention relates to a lithium battery technology, in particular to a lithium battery charging and discharging protection circuit of a new energy automobile and a controllable voltage source adjusting method.
Background
Along with the recent years, people pay attention to environmental protection continuously and then adopt different modes to reduce environmental pollution, and the development of new energy automobile reduces exhaust emission, effectual environmental protection, and electric automobile can not produce tail gas, does not pollute, and the noise is little has reduced the influence to the environment, and providing the source of power for the new energy, is storing the electric energy through the lithium cell and running, puts forward higher requirement to the safety of lithium cell like this.
When the charging surface of the lithium battery is opposite to the input voltage which is converted, the lithium battery cannot be effectively controlled, so that the continuous transmission of the damaged voltage is caused, the stability of an operation and detection device is influenced, and further potential safety hazards are generated; the lithium battery is overcharged due to the fact that the lithium battery cannot be timely controlled when the damaged voltage enters, physical reaction occurs, and therefore the periodicity of lithium battery replacement caused by electric energy storage is reduced, so that not only is environmental protection not improved, but also environmental pollution is aggravated; the lithium battery can continuously output stored electric energy when discharging, so that the voltage is slowly reduced, and the lithium battery continues to discharge to a voltage set value to form over discharge, so that the active substances of the electrode are damaged to lose the reaction capability, and the service life of the lithium battery is shortened.
Disclosure of Invention
The purpose of the invention is as follows: the charge and discharge protection circuit for the lithium battery of the new energy automobile is provided to solve the problems.
The technical scheme is as follows: a new energy automobile lithium battery charge-discharge protection circuit includes:
the overcharge protection module is used for controlling the on-off of the triode when the voltage of the electricity storage equipment reaches saturation so as to continuously supply power to the resistance voltage;
the voltage control module is used for transmitting the acquired voltage and feeding back the saturation value of the power storage equipment;
the overcurrent operation module is used for comparing the acquired current with the set current so as to protect the power storage equipment;
the discharge protection module is used for adjusting the storage voltage during discharge and protecting components and lithium batteries in the discharge process;
the overdischarge adjusting module is used for reducing the practical service life of the lithium battery for excessively releasing electric energy and further controlling the overdischarge voltage output value.
According to one aspect of the invention, the triode Q3 in the overcharge protection module obtains the feedback voltage value of the voltage control module through the base terminal, so that the emitter terminal is conducted to block the overcharge voltage from passing through;
a transistor Q6 in the voltage control module is used as a non-contact switch to transmit the control ground voltage to the overcurrent operation module;
the overcurrent operation module compares the set ground current parameter with the received current through the operational amplifier U2 to start the protection device, and the capacitor C4 provides storage voltage for the operational amplifier U2 to improve the operation speed;
the diode D7 in the discharge protection module is used for unidirectional output of voltage to prevent reverse transmission of voltage during discharge;
capacitor C8 is used for the insufficient current of lithium cell B1 when overdischarging in the regulation module of overdischarging, and then provides the storage voltage and reduces the discharge apparatus damage.
According to one aspect of the invention, the discharge protection module comprises a controllable voltage source adjusting module, wherein the controllable voltage source adjusting module comprises a resistor R, a capacitor C, an inductor 1, a capacitor C, an inductor 2, an operational amplifier U, a resistor R, a triode Q and a variable resistor RV, one end of the resistor R is connected with an INPUT voltage INPUT, the other end of the resistor R is respectively connected with one end of the resistor R and one end of the capacitor C, the other end of the resistor R is connected with a ground wire GND, the other end of the capacitor C is respectively connected with one end of the inductor 1 and one end of the capacitor C, the other end of the inductor 1 is respectively connected with one end of an operational amplifier U pin 3, one end of an operational amplifier U pin 6, one end of the resistor R and one end of the resistor R, the other end of the capacitor C is respectively connected with one end of the inductor 2 and the operational amplifier U pin 2, a pin 7 of the operational amplifier U pin is connected with a power supply +6V, a pin 4 of the operational amplifier U pin is respectively connected with the other end of the inductor 2, the positive electrode end of a diode D, the triode Q end and the ground wire, the other end of the resistor R is respectively connected with a variable resistor RV.
According to one aspect of the invention, the overcharge protection module comprises a resistor R1, a resistor R2, a diode D1, a triode Q1, a resistor R3, a resistor R4, a capacitor C1, a diode D3, a triode Q2, a resistor R5, a diode D2 and a triode Q3, wherein one end of the resistor R1 is connected with one end of a resistor R2, one end of a base end of a triode Q1 and an INPUT voltage INPUT, the other end of the resistor R1 is connected with one end of a resistor R3 and one end of an inductor L1, the other end of the resistor R3 is connected with a collector end of a triode Q1 and one end of a resistor R4, the other end of the resistor R2 is connected with a cathode end of a diode D1, the anode end of the diode D1 is connected with an emitter end of the triode Q1, the diode D1 and a ground wire, the cathode end of the diode D1 is connected with the emitter end of the base end of the triode Q1, the collector end of the triode Q1 and the cathode end of the diode D1 are connected with the emitter end of the anode end of the diode D1 and the emitter end of the diode D1, and the anode end of the diode D1, and the emitter end of the diode.
According to one aspect of the invention, the voltage control module comprises a transistor Q6, a resistor R6, a resistor R7, a resistor R8, a capacitor C3 and a thermal protector U1, wherein a pin 1 of the thermal protector U1 is connected with one end of a resistor R6, a pin 2 of the thermal protector U1 is connected with a base end of a triode Q3, a pin 3 of the thermal protector U1 is connected with one end of the resistor R7, a pin 4 of the thermal protector U1 is connected with one end of a resistor R8, a pin 5 of the thermal protector U1 is connected with the other end of the resistor R5, a negative end of a capacitor C3 and a ground wire GND respectively, the other end of the resistor R6 is connected with a pin 2 of a transistor Q6, a collector end of a triode Q6 and a negative end of a diode D6 respectively, a pin 1 of the transistor Q6 is connected with the other end of an inductor 6, and a pin 3 of the transistor Q6 is connected with the other end of.
According to one aspect of the invention, the overcurrent operation module comprises a resistor R9, a resistor R10, a capacitor C2, an operational amplifier U2, a capacitor C4, a resistor R11, a resistor R12, a capacitor C6, an operational amplifier U3, a resistor R13 and a capacitor C3, wherein one end of the resistor R9 is connected with a pin 3 of a transistor Q6, the other end of a resistor R7, the other end of a resistor R8 and the positive end of a capacitor C3 respectively; the other end of the resistor R9 is respectively connected with one end of a capacitor C2 and a pin 3 of an operational amplifier U2; the other end of the capacitor C2 is respectively connected with one end of a resistor R10 and a pin 2 of an operational amplifier U2; the other end of the resistor R10 is connected with a ground wire GND; the pin 7 of the operational amplifier U2 is respectively connected with one end of a capacitor C4 and a power supply + 6V; the other end of the capacitor C4 is connected with a ground wire GND; pin 4 of the operational amplifier U2 is connected with a ground wire GND; pin 6 of the operational amplifier U2 is connected with one end of a resistor R11; the other end of the resistor R11 is respectively connected with one end of a capacitor C5 and one end of a resistor R12; the other end of the resistor R12 is respectively connected with the positive end of the capacitor C6 and the pin 2 of the operational amplifier U3; the negative end of the capacitor C6 is connected with a ground wire GND; the pin 3 of the operational amplifier U3 is connected with one end of a resistor R13; the other end of the resistor R13 is respectively connected with the pin 6 of the operational amplifier U3 and the other end of the capacitor C5; pin 4 of the operational amplifier U3 is connected with a ground wire GND; pin 7 of the op amp U3 is connected to the +6V power supply.
According to one aspect of the invention, the discharge protection module comprises a lithium battery B1, a switch SB1, a diode D7, a triode Q5, a resistor R16, a capacitor C9, a resistor R14, a triode Q4, a capacitor C7, a resistor R15, a resistor R17, a diode D4, a resistor R18, a transistor Q7 and a transistor Q8, wherein the positive terminal of the lithium battery B1 is respectively connected with one end of the switch SB1, the other end of the resistor R13, a pin 6 of an operational amplifier U3 and the other end of the capacitor C5; the negative end of the lithium battery B1 is respectively connected with a collector end of a triode Q5, a positive end of a capacitor C9, a negative end of a diode D4, one end of a resistor R18 and a pin 3 of a transistor Q8; the other end of the switch SB1 is respectively connected with the cathode end of the diode D7 and the emitter end of the triode Q5; the positive end of the diode D7 is respectively connected with the positive end of the capacitor C7 and one end of the resistor R14; the negative end of the capacitor C7 is respectively connected with one end of a resistor R15 and a ground wire GND; the other end of the resistor R15 is respectively connected with the other end of the resistor R14 and the base terminal of the triode Q4; the collector terminal of the triode Q4 is connected with one end of a resistor R16; the other end of the resistor R16 is connected with the base terminal of a triode Q5; the emitter terminal of the triode Q4 is connected with the cathode terminal of the capacitor C9; the positive end of the diode D4 is respectively connected with a pin 2 of a transistor Q7 and one end of a resistor R17; the other end of the resistor R17 is respectively connected with a pin 1 of a transistor Q7 and a ground wire GND; and the pin 3 of the transistor Q7 is respectively connected with the other end of the resistor R18 and the pin 2 of the transistor Q8.
According to one aspect of the invention, the over-discharge adjusting module comprises a resistor R20, a resistor R19, a diode D5, a capacitor C8, a diode D6, a capacitor C10 and a resistor R21, wherein one end of the resistor R19 is respectively connected with the positive terminal of the diode D5, one end of the capacitor C8 and a pin 1 of a transistor Q8; the other end of the resistor R19 is respectively connected with one end of a resistor R20, the negative electrode end of a diode D5, the other end of a capacitor C8, the positive electrode end of a diode D6, one end of a capacitor C10, one end of a resistor R21 and OUTPUT voltage OUTPUT; the other end of the resistor R21 is connected with the other end of the capacitor C10; and the negative electrode end of the diode D6 is respectively connected with the other end of the resistor R21 and the ground wire GND.
According to one aspect of the present invention, the diode D1, the diode D2, the diode D4, the diode D5, the diode D6, the diode D6 are zener diodes; the model of the triode Q5 is PNP; the model of the triode Q1, the triode Q2, the triode Q3 and the triode Q4 is NPN; the capacitor C3, the capacitor C6 and the capacitor C7 are electrolytic capacitors; the thermal protector is U1 model BW 9700.
According to one aspect of the invention, the controllable voltage source adjusting method of the new energy automobile lithium battery charging and discharging protection circuit is characterized in that the controllable voltage source adjusting module obtains voltage through a lithium battery in the discharging protection module so as to adjust the output voltage; the method comprises the following specific steps:
step 1, INPUT voltage INPUT is conducted, a resistor R1 and a resistor R2 are provided for different voltage division values of a circuit through series voltage division characteristics, a capacitor C1 and a capacitor C2 are used as energy storage elements and used for releasing when necessary and providing the operation speed of an operational amplifier U1, an inductor L1 converts obtained electric energy into magnetic energy for storage, the magnetic energy is used for keeping the output current unchanged through an inductor L1 and maintaining the stability of the current, and the resistor R5 and the resistor R4 reduce the obtained voltage value through the resistance value of the resistor R5 and the obtained voltage value to meet the requirement of adjusting the output according to the obtained voltage value;
and 2, the diode D1 has unidirectional conductivity to limit the conduction direction to protect reverse conduction to cause equipment damage, the triode Q1 is used for controlling the conduction of voltage regulated by the resistor R4 through a contactless switch, and the variable resistor RV1 regulates the OUTPUT voltage OUTPUT value according to the movement of the upper position and the lower position of the pin 3, so that different OUTPUT voltage sources are realized through regulation.
Has the advantages that: the invention designs a new energy automobile lithium battery charging and discharging protection circuit and a controllable voltage source adjusting method, which can not be effectively controlled when the input voltage is changed, so that the continuous output of the damaged voltage is caused, the stability of an operation and detection device is influenced, the damaged voltage is degraded through the diagnosis of the effective voltage of a triode Q1 and the feedback of a resistor R1 and a resistor R2 when the voltage is input, so that the low-power output is generated, and the triode Q3 feeds back the voltage value through a voltage control module obtained from a base terminal end, so that an emitter terminal is conducted to pass through the resistor R5 with the resistance value of overcharging voltage; when the damaged voltage enters, the lithium battery is not controlled in time to cause overcharge, the obtained voltage is stored in the capacitor C2 and the capacitor C6 respectively to adjust the damaged voltage so as to transmit the damaged voltage to required power supply equipment, and then the voltage parameter set by the operational amplifier U2 is compared with the received current so as to form overcurrent protection and reduce the damage of the lithium battery; when the lithium battery discharges, the capacitor C8 provides stored electric energy for the lithium battery when the lithium battery discharges, so that the conduction of the voltage of the transistor Q8 is controlled, and the over-discharge is prevented.
Drawings
Fig. 1 is a block diagram of the present invention.
Fig. 2 is a distribution diagram of the lithium battery charging and discharging protection circuit of the present invention.
Fig. 3 is a circuit diagram of an overcharge protection module of this invention.
Fig. 4 is a circuit diagram of a discharge protection module of the present invention.
Fig. 5 is a diagram of a controllable voltage source regulation circuit of the present invention.
Detailed Description
As shown in fig. 1, in this embodiment, a charge and discharge protection circuit for a lithium battery of a new energy vehicle includes:
the overcharge protection module is used for controlling the on-off of the triode when the voltage of the electricity storage equipment reaches saturation so as to continuously supply power to the resistance voltage;
the voltage control module is used for transmitting the acquired voltage and feeding back the saturation value of the power storage equipment;
the overcurrent operation module is used for comparing the acquired current with the set current so as to protect the power storage equipment;
the discharge protection module is used for adjusting the storage voltage during discharge and protecting components and lithium batteries in the discharge process;
the overdischarge adjusting module is used for reducing the practical service life of the lithium battery for excessively releasing electric energy and further controlling the overdischarge voltage output value.
In a further embodiment, as shown in fig. 2, the transistor Q3 in the overcharge protection module obtains the feedback voltage value of the voltage control module through the base terminal, so that the emitter terminal is turned on to block the overcharge voltage from passing through;
a transistor Q6 in the voltage control module is used as a non-contact switch to transmit the control ground voltage to the overcurrent operation module;
the overcurrent operation module compares the set ground current parameter with the received current through the operational amplifier U2 to start the protection device, and the capacitor C4 provides storage voltage for the operational amplifier U2 to improve the operation speed;
the diode D7 in the discharge protection module is used for unidirectional output of voltage to prevent reverse transmission of voltage during discharge;
and the capacitor C8 in the over-discharge regulating module is used for generating a defect point of the lithium battery B1 when the over-discharge is carried out, so that the storage voltage is provided for reducing the damage of a discharging device.
In a further embodiment, as shown in fig. 5, the controllable voltage source regulating module includes a resistor R1, a resistor R2, a capacitor C1, an inductor L1, a capacitor C2, an inductor L2, an operational amplifier U1, a resistor R4, a resistor R5, a transistor Q1, and a variable resistor RV 1.
In a further embodiment, one end of a resistor R1 in the controllable voltage source adjusting module is connected with an INPUT voltage INPUT, the other end of the resistor R1 is connected with one end of a resistor R2 and one end of a capacitor C1 respectively, the other end of the resistor R2 is connected with a ground GND, the other end of the capacitor C1 is connected with one end of an inductor L1 and one end of a capacitor C2 respectively, the other end of an inductor L is connected with one end of a pin 3 of an operational amplifier U1, a pin 6 of an operational amplifier U1, one end of a resistor R5 and one end of a resistor R4 respectively, the other end of a capacitor C2 is connected with one end of an inductor L and a pin 2 of an operational amplifier U1 respectively, a pin 7 of the operational amplifier U1 is connected with a power supply +6V, a pin 4 of the operational amplifier U1 is connected with the other end of the inductor 1, a positive collector end of a diode D1, a triode Q1 end and the ground, and the other end of the resistor R1 is connected with a variable resistor RV1 and a triode Q1 terminal, and a variable OUTPUT voltage OUTPUT terminal of a variable OUTPUT diode T1.
In a further embodiment, as shown in fig. 3, the overcharge protection module includes a resistor R1, a resistor R2, a diode D1, a transistor Q1, a resistor R3, a resistor R4, a capacitor C1, a diode D3, a transistor Q2, a resistor R5, a diode D2, and a transistor Q3.
In a further embodiment, one end of a resistor R1 in the overcharge protection module is connected with one end of a resistor R2, a base end of a triode Q1 and INPUT voltage INPUT, the other end of a resistor R1 is connected with one end of the resistor R3 and one end of an inductor L1, the other end of the resistor R3 is connected with a collector end of a triode Q1 and one end of a resistor R4, the other end of the resistor R2 is connected with a cathode end of a diode D1, a positive end of the diode D1 is connected with an emitter end of a triode Q1, a positive end of a diode D3 and ground GND, a negative end of the diode D3 is connected with a base end of a triode Q2, a collector end of a triode Q2 is connected with one end of a capacitor C1, the other end of the capacitor C1 is connected with the other end of a resistor R4 and a positive end of a diode D2, an emitter end of the triode Q2 is connected with one end of a collector end of a resistor R2 and an emitter end.
In a further embodiment, the voltage control module includes a transistor Q6, a resistor R6, a resistor R7, a resistor R8, a capacitor C3, and a thermal protector U1.
In a further embodiment, in the voltage control module, a pin 1 of a thermal protector U1 is connected with one end of a resistor R6, a pin 2 of a thermal protector U1 is connected with a base end of a triode Q3, a pin 3 of a thermal protector U1 is connected with one end of a resistor R7, a pin 4 of a thermal protector U1 is connected with one end of a resistor R8, a pin 5 of the thermal protector U1 is respectively connected with the other end of the resistor R5, a negative end of a capacitor C3 and a ground wire GND, the other end of the resistor R6 is respectively connected with a pin 2 of a transistor Q6, a collector end of a triode Q3 and a negative end of a diode D2, a pin 1 of the transistor Q6 is connected with the other end of an inductor L, and a pin 3 of the transistor Q6 is respectively connected with the other end of the resistor R7.
In a further embodiment, the over-current operation module includes a resistor R9, a resistor R10, a capacitor C2, an operational amplifier U2, a capacitor C4, a resistor R11, a resistor R12, a capacitor C6, an operational amplifier U3, a resistor R13, and a capacitor C3.
In a further embodiment, one end of the resistor R9 in the over-current operation module is respectively connected to the pin 3 of the transistor Q6, the other end of the resistor R7, the other end of the resistor R8, and the positive terminal of the capacitor C3; the other end of the resistor R9 is respectively connected with one end of a capacitor C2 and a pin 3 of an operational amplifier U2; the other end of the capacitor C2 is respectively connected with one end of a resistor R10 and a pin 2 of an operational amplifier U2; the other end of the resistor R10 is connected with a ground wire GND; the pin 7 of the operational amplifier U2 is respectively connected with one end of a capacitor C4 and a power supply + 6V; the other end of the capacitor C4 is connected with a ground wire GND; pin 4 of the operational amplifier U2 is connected with a ground wire GND; pin 6 of the operational amplifier U2 is connected with one end of a resistor R11; the other end of the resistor R11 is respectively connected with one end of a capacitor C5 and one end of a resistor R12; the other end of the resistor R12 is respectively connected with the positive end of the capacitor C6 and the pin 2 of the operational amplifier U3; the negative end of the capacitor C6 is connected with a ground wire GND; the pin 3 of the operational amplifier U3 is connected with one end of a resistor R13; the other end of the resistor R13 is respectively connected with the pin 6 of the operational amplifier U3 and the other end of the capacitor C5; pin 4 of the operational amplifier U3 is connected with a ground wire GND; pin 7 of the op amp U3 is connected to the +6V power supply.
In a further embodiment, as shown in fig. 4, the discharge protection module includes a lithium battery B1, a switch SB1, a diode D7, a transistor Q5, a resistor R16, a capacitor C9, a resistor R14, a transistor Q4, a capacitor C7, a resistor R15, a resistor R17, a diode D4, a resistor R18, a transistor Q7, and a transistor Q8.
In a further embodiment, the positive terminal of the lithium battery B1 in the discharge protection module is respectively connected to one terminal of a switch SB1, the other terminal of a resistor R13, a pin 6 of an operational amplifier U3, and the other terminal of a capacitor C5; the negative end of the lithium battery B1 is respectively connected with a collector end of a triode Q5, a positive end of a capacitor C9, a negative end of a diode D4, one end of a resistor R18 and a pin 3 of a transistor Q8; the other end of the switch SB1 is respectively connected with the cathode end of the diode D7 and the emitter end of the triode Q5; the positive end of the diode D7 is respectively connected with the positive end of the capacitor C7 and one end of the resistor R14; the negative end of the capacitor C7 is respectively connected with one end of a resistor R15 and a ground wire GND; the other end of the resistor R15 is respectively connected with the other end of the resistor R14 and the base terminal of the triode Q4; the collector terminal of the triode Q4 is connected with one end of a resistor R16; the other end of the resistor R16 is connected with the base terminal of a triode Q5; the emitter terminal of the triode Q4 is connected with the cathode terminal of the capacitor C9; the positive end of the diode D4 is respectively connected with a pin 2 of a transistor Q7 and one end of a resistor R17; the other end of the resistor R17 is respectively connected with a pin 1 of a transistor Q7 and a ground wire GND; and the pin 3 of the transistor Q7 is respectively connected with the other end of the resistor R18 and the pin 2 of the transistor Q8.
In a further embodiment, the over-discharge regulation module includes a resistor R20, a resistor R19, a diode D5, a capacitor C8, a diode D6, a capacitor C10, and a resistor R21.
In a further embodiment, one end of the resistor R19 in the over-discharge regulation module is respectively connected to the positive terminal of the diode D5, one end of the capacitor C8, and the pin 1 of the transistor Q8; the other end of the resistor R19 is respectively connected with one end of a resistor R20, the negative electrode end of a diode D5, the other end of a capacitor C8, the positive electrode end of a diode D6, one end of a capacitor C10, one end of a resistor R21 and OUTPUT voltage OUTPUT; the other end of the resistor R21 is connected with the other end of the capacitor C10; and the negative electrode end of the diode D6 is respectively connected with the other end of the resistor R21 and the ground wire GND.
In a further embodiment, the diode D1, the diode D2, the diode D4, the diode D5, the diode D6, the diode D6 are zener diodes; the model of the triode Q5 is PNP; the model of the triode Q1, the triode Q2, the triode Q3 and the triode Q4 is NPN; the capacitor C3, the capacitor C6 and the capacitor C7 are electrolytic capacitors; the thermal protector is U1 model BW 9700.
In a further embodiment, the method for adjusting the controllable voltage source of the new energy automobile lithium battery charging and discharging protection circuit is characterized in that the controllable voltage source adjusting module obtains voltage through the lithium battery in the discharging protection module, and then adjusts the output voltage; the method comprises the following specific steps:
step 1, INPUT voltage INPUT is conducted, a resistor R1 and a resistor R2 are provided for different voltage division values of a circuit through series voltage division characteristics, a capacitor C1 and a capacitor C2 are used as energy storage elements and used for releasing when necessary and providing the operation speed of an operational amplifier U1, an inductor L1 converts obtained electric energy into magnetic energy for storage, the magnetic energy is used for keeping the output current unchanged through an inductor L1 and maintaining the stability of the current, and the resistor R5 and the resistor R4 reduce the obtained voltage value through the resistance value of the resistor R5 and the obtained voltage value to meet the requirement of adjusting the output according to the obtained voltage value;
and 2, the diode D1 has unidirectional conductivity to limit the conduction direction to protect reverse conduction to cause equipment damage, the triode Q1 is used for controlling the conduction of voltage regulated by the resistor R4 through a contactless switch, and the variable resistor RV1 regulates the OUTPUT voltage OUTPUT value according to the movement of the upper position and the lower position of the pin 3, so that different OUTPUT voltage sources are realized through regulation.
In summary, the present invention has the following advantages: the resistor R1 and the resistor R2 degrade the damaged voltage, so that the output power is adjusted, the triode Q1 diagnoses the effective voltage, the diode D2 and the diode D3 control the unidirectional output direction of the voltage, and the triode Q3 obtains the feedback voltage value of the voltage control module through the base terminal, so that the emitter terminal is conducted to block the overcharge voltage from passing through; the resistor R6, the resistor R7 and the resistor R8 regulate output voltage, the capacitor C3 provides starting voltage for the thermal protector U1 to reduce discharge phenomenon caused by instant starting, and the transistor Q6 is used as a non-contact switch to transmit control ground voltage to the overcurrent operation module; the operational amplifier U2 is started by comparing the set ground current parameter with the received current, the capacitor C4 provides the operational amplifier U2 with the stored voltage to improve the operational speed, and the capacitor C2 and the capacitor C6 respectively store the obtained voltage to adjust the damaged voltage so as to meet the requirement of stable voltage output; the triode Q5 emitter terminal obtains the conduction condition of the voltage provided by the lithium battery B1, the obtained voltage is transmitted to the capacitor C9 and the capacitor C7 through the base terminal, the obtained voltage is stored by the capacitor, the lithium battery B1 is protected to provide stored electric energy when power is insufficient, the stability of the lithium battery is maintained, the diode D7 is used for unidirectional output of the voltage to prevent reverse transmission of the voltage during discharging, the voltage value obtained by the transistor Q7 through the pin 2 is larger than that obtained by the pin 3 to realize that the pin 2 of the transistor Q8 is electrified, and further the voltage is transmitted; capacitor C8 appears insufficient voltage when being used for overdischarging lithium cell B1, and capacitor C10 will store when voltage release and then block the output protection overdischarge of voltage and cause the decay of lithium cell life-span, and then the guarantee of safety when protecting lithium cell charge-discharge.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

Claims (9)

1. The utility model provides a new energy automobile lithium cell charge-discharge protection circuit which characterized in that, includes following module:
the overcharge protection module is used for controlling the on-off of the triode when the voltage of the electricity storage equipment reaches saturation so as to continuously supply power to the resistance voltage;
the voltage control module is used for transmitting the acquired voltage and feeding back the saturation value of the power storage equipment;
the overcurrent operation module is used for comparing the acquired current with the set current so as to protect the power storage equipment;
the discharge protection module is used for adjusting the storage voltage during discharge and protecting components and lithium batteries in the discharge process;
the overdischarge adjusting module is used for reducing the practical service life of the lithium battery for excessively releasing electric energy and further controlling the overdischarge voltage output value.
2. The charging and discharging protection circuit of the lithium battery of the new energy automobile as claimed in claim 1, wherein the triode Q3 in the overcharge protection module obtains a voltage feedback value of the voltage control module through a base terminal, so that an emitter terminal is conducted to block an overcharge voltage from passing through;
a transistor Q6 in the voltage control module is used as a non-contact switch to transmit the control ground voltage to the overcurrent operation module;
the operational amplifier U2 in the overcurrent operation module is started by comparing the set ground current parameter with the received current, and the capacitor C4 provides the storage voltage for the operational amplifier U2 to improve the operation speed;
the diode D7 in the discharge protection module is used for unidirectional output of voltage to prevent reverse transmission of voltage during discharge;
capacitor C8 is used for the insufficient current of lithium cell B1 when overdischarging in the regulation module of overdischarging, and then provides the storage voltage and reduces the discharge apparatus damage.
3. The charging and discharging protection circuit of the lithium battery of the new energy automobile according to claim 1, and is characterized in that the charging and discharging protection module comprises a controllable voltage source adjusting module, wherein the controllable voltage source adjusting module comprises a resistor R1, a resistor R2, a capacitor C1, an inductor L1, a capacitor C2, an inductor L2, an operational amplifier U1, a resistor R4, a resistor R5, a triode Q1 and a variable resistor RV1, one end of the resistor R1 is connected with an INPUT voltage INPUT, the other end of the resistor R1 is connected with one end of a resistor R2 and one end of a capacitor C1, the other end of the resistor R2 is connected with a ground wire GND, the other end of the capacitor C1 is connected with one end of an inductor L1 and one end of a capacitor C2, the other end of the inductor L1 is connected with one end of an operational amplifier U1 pin 3, a pin 1 pin 6, one end of a resistor R1 and a triode T1, the other end of the operational amplifier U1 is connected with a triode Q1, the operational amplifier and the OUTPUT terminal of the triode T1, the operational amplifier and the OUTPUT resistor R1, the anode of the triode Q1 is connected with the anode of the variable resistor D1, the anode 1 and the triode Q1, the operational amplifier.
4. The charging and discharging protection circuit of the lithium battery of the new energy automobile according to claim 1, wherein the overcharge protection module comprises a resistor R1, a resistor R2, a diode D1, a triode Q1, a resistor R3, a resistor R4, a capacitor C1, a diode D3, a triode Q2, a resistor R5, a diode D2 and a triode Q3, one end of the resistor R1 is connected with one end of a resistor R2, a base end of a triode Q1 and an INPUT voltage INPUT, the other end of the resistor R1 is connected with one end of a resistor R3 and one end of an inductor L1, the other end of the resistor R3 is connected with a collector end of a triode Q1 and one end of a resistor R4, the other end of the resistor R2 is connected with a cathode end of a diode D1, an anode end of the diode D1 is connected with an emitter end of the triode Q1, a cathode end of the diode D1 and a cathode end of the triode Q1, and a cathode end of the resistor R1 are connected with an emitter end of the triode Q1 and a cathode end of the diode C1 and a capacitor C1, and a triode Q1 are connected with a cathode end of the emitter and a diode C1.
5. The charging and discharging protection circuit of the lithium battery of the new energy automobile according to claim 1, wherein the voltage control module comprises a transistor Q6, a resistor R6, a resistor R7, a resistor R8, a capacitor C3 and a thermal protector U1, wherein a pin 1 of the thermal protector U1 is connected with one end of a resistor R6, a pin 2 of the thermal protector U1 is connected with a base end of a triode Q3, a pin 3 of the thermal protector U1 is connected with one end of a resistor R7, a pin 4 of the thermal protector U1 is connected with one end of a resistor R8, a pin 5 of the thermal protector U1 is connected with the other end of a resistor R3, a negative end of a capacitor C3 and a ground wire GND respectively, the other end of the resistor R6 is connected with a pin 2 of a transistor Q6, a negative end of a triode Q6 and a negative end of a diode D6 respectively, a pin 1 of the transistor Q6 is connected with the other end of an inductor 6, and a pin 3 of the transistor Q6 is connected with the other end of a.
6. The charging and discharging protection circuit for the lithium battery of the new energy automobile as claimed in claim 1, wherein the overcurrent operation module comprises a resistor R9, a resistor R10, a capacitor C2, an operational amplifier U2, a capacitor C4, a resistor R11, a resistor R12, a capacitor C6, an operational amplifier U3, a resistor R13 and a capacitor C3, wherein one end of the resistor R9 is connected to a pin 3 of a transistor Q6, the other end of the resistor R7, the other end of the resistor R8 and the positive end of the capacitor C3 respectively; the other end of the resistor R9 is respectively connected with one end of a capacitor C2 and a pin 3 of an operational amplifier U2; the other end of the capacitor C2 is respectively connected with one end of a resistor R10 and a pin 2 of an operational amplifier U2; the other end of the resistor R10 is connected with a ground wire GND; the pin 7 of the operational amplifier U2 is respectively connected with one end of a capacitor C4 and a power supply + 6V; the other end of the capacitor C4 is connected with a ground wire GND; pin 4 of the operational amplifier U2 is connected with a ground wire GND; pin 6 of the operational amplifier U2 is connected with one end of a resistor R11; the other end of the resistor R11 is respectively connected with one end of a capacitor C5 and one end of a resistor R12; the other end of the resistor R12 is respectively connected with the positive end of the capacitor C6 and the pin 2 of the operational amplifier U3; the negative end of the capacitor C6 is connected with a ground wire GND; the pin 3 of the operational amplifier U3 is connected with one end of a resistor R13; the other end of the resistor R13 is respectively connected with the pin 6 of the operational amplifier U3 and the other end of the capacitor C5; pin 4 of the operational amplifier U3 is connected with a ground wire GND; pin 7 of the op amp U3 is connected to the +6V power supply.
7. The charge and discharge protection circuit of the lithium battery of the new energy automobile as claimed in claim 1, wherein the discharge protection module comprises a lithium battery B1, a switch SB1, a diode D7, a triode Q5, a resistor R16, a capacitor C9, a resistor R14, a triode Q4, a capacitor C7, a resistor R15, a resistor R17, a diode D4, a resistor R18, a transistor Q7 and a transistor Q8, wherein the positive terminal of the lithium battery B1 is respectively connected with one end of the switch SB1, the other end of the resistor R13, a pin 6 of an operational amplifier U3 and the other end of the capacitor C5; the negative end of the lithium battery B1 is respectively connected with a collector end of a triode Q5, a positive end of a capacitor C9, a negative end of a diode D4, one end of a resistor R18 and a pin 3 of a transistor Q8; the other end of the switch SB1 is respectively connected with the cathode end of the diode D7 and the emitter end of the triode Q5; the positive end of the diode D7 is respectively connected with the positive end of the capacitor C7 and one end of the resistor R14; the negative end of the capacitor C7 is respectively connected with one end of a resistor R15 and a ground wire GND; the other end of the resistor R15 is respectively connected with the other end of the resistor R14 and the base terminal of the triode Q4; the collector terminal of the triode Q4 is connected with one end of a resistor R16; the other end of the resistor R16 is connected with the base terminal of a triode Q5; the emitter terminal of the triode Q4 is connected with the cathode terminal of the capacitor C9; the positive end of the diode D4 is respectively connected with a pin 2 of a transistor Q7 and one end of a resistor R17; the other end of the resistor R17 is respectively connected with a pin 1 of a transistor Q7 and a ground wire GND; and the pin 3 of the transistor Q7 is respectively connected with the other end of the resistor R18 and the pin 2 of the transistor Q8.
8. The charge and discharge protection circuit for the lithium battery of the new energy automobile as claimed in claim 1, wherein the over-discharge regulation module comprises a resistor R20, a resistor R19, a diode D5, a capacitor C8, a diode D6, a capacitor C10, and a resistor R21, wherein one end of the resistor R19 is connected to a positive terminal of the diode D5, one end of the capacitor C8, and a pin 1 of a transistor Q8, respectively; the other end of the resistor R19 is respectively connected with one end of a resistor R20, the negative electrode end of a diode D5, the other end of a capacitor C8, the positive electrode end of a diode D6, one end of a capacitor C10, one end of a resistor R21 and OUTPUT voltage OUTPUT; the other end of the resistor R21 is connected with the other end of the capacitor C10; and the negative electrode end of the diode D6 is respectively connected with the other end of the resistor R21 and the ground wire GND.
9. The method for regulating the controllable voltage source of the charge and discharge protection circuit of the lithium battery of the new energy automobile as claimed in claim 3, wherein the controllable voltage source regulating module obtains the voltage through the lithium battery in the discharge protection module, and further regulates the output voltage; the method comprises the following specific steps:
step 1, INPUT voltage INPUT is conducted, a resistor R1 and a resistor R2 are provided for different voltage division values of a circuit through series voltage division characteristics, a capacitor C1 and a capacitor C2 are used as energy storage elements and used for releasing when necessary and providing the operation speed of an operational amplifier U1, an inductor L1 converts obtained electric energy into magnetic energy for storage, the magnetic energy is used for keeping the output current unchanged through an inductor L1 and maintaining the stability of the current, and the resistor R5 and the resistor R4 reduce the obtained voltage value through the resistance value of the resistor R5 and the obtained voltage value to meet the requirement of adjusting the output according to the obtained voltage value;
and 2, the diode D1 has unidirectional conductivity to limit the conduction direction to protect reverse conduction to cause equipment damage, the triode Q1 is used for controlling the conduction of voltage regulated by the resistor R4 through a contactless switch, and the variable resistor RV1 regulates the OUTPUT voltage OUTPUT value according to the movement of the upper position and the lower position of the pin 3, so that different OUTPUT voltage sources are realized through regulation.
CN202010243823.2A 2020-03-31 2020-03-31 New energy automobile lithium battery charging and discharging protection circuit and controllable voltage source adjusting method Withdrawn CN111439164A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112214042A (en) * 2020-09-14 2021-01-12 南京骞翮物联网科技有限公司 Sewage discharge control system based on Internet of things and control method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112214042A (en) * 2020-09-14 2021-01-12 南京骞翮物联网科技有限公司 Sewage discharge control system based on Internet of things and control method thereof

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Application publication date: 20200724