CN111106648A

CN111106648A - System and method for parallel discharge operation of multiple battery packs

Info

Publication number: CN111106648A
Application number: CN201911377166.4A
Authority: CN
Inventors: 段志刚
Original assignee: Beijing Xingda Zhilian Technology Co ltd
Current assignee: Beijing Xingda Zhilian Technology Co ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-05-05
Anticipated expiration: 2039-12-27
Also published as: CN111106648B

Abstract

The invention relates to the field of battery energy storage conversion power supply, and provides a multi-battery-pack dynamic hot standby redundant parallel discharge operation system and method aiming at the technical defect that a multi-battery pack in the prior art cannot be simultaneously subjected to hot standby redundant parallel operation. The invention utilizes the composite switch protection and the built-in conversion discharge mechanism of the electric type controlled discharge battery pack to ensure that the battery pack has the specific controlled electric type characteristic, becomes a programmable constant-voltage constant-current volt-ampere and droop volt-ampere characteristic, unidirectional discharge, autonomous current sharing and intelligent programmable modular device, and realizes the redundant parallel discharge operation of the heat backup of the multi-battery pack. Especially, through power switch conversion and control, unexpected reverse current is avoided, power conversion output specific voltage current and impedance control and autonomous dynamic current sharing are realized, so that each battery pack in the system can realize unidirectional output, adjustable constant voltage stabilization or linear droop, adjustable constant current limiting and autonomous current sharing discharge, and the function of multi-battery pack dynamic hot standby redundant parallel current sharing discharge is achieved.

Description

System and method for parallel discharge operation of multiple battery packs

Technical Field

The invention relates to the field of battery energy storage conversion power supply, in particular to a system and a method for parallel discharge operation of a plurality of power battery packs.

Background

The power battery pack is a core component of the new energy equipment; the power single battery core has low rated voltage and small rated capacity, so a plurality of battery cores are combined into the whole energy storage component in a series-parallel connection mode, which is commonly called a power battery pack. The key points of the battery pack design comprise monomer voltage, monomer capacity, a monomer series-parallel connection mode and a battery system management mode. The charge and discharge management of the battery pack is a key technology used by a system, usually, a management unit BPU (Business Process Unit) in the battery pack is commonly called a protection board and provides overcharge and overdischarge protection for the battery pack, and except for output short circuit protection, the battery pack is generally mainly used for monitoring the voltage of a single battery in a battery pack string; the charging process is completed by a specially configured charger according to the specified type of battery charging standard process and the specified parameters of a manufacturer, the battery pack is generally designed with over-low voltage protection in the discharging process, including the protection of over-low voltage of the whole group and over-low voltage of a single battery, and part of the battery packs are also designed with short circuit or time-limited over-current protection and over-temperature protection.

The power battery large system is an energy package system formed by multiple monomers, wherein the monomers are generally formed into a package component according to a preset series-parallel mode, the package component is formed into a block or a layer, and then the large system is formed according to the layer. The small system is reduced to a package component. The parallel connection part of the circuit generally adopts a fuse series configuration, and local thermal management and capacity management are implemented so as to avoid the problem that the system cannot normally operate due to internal circulation among different battery pack components. The design is only implemented in parallel connection when the assembly is started, and the parallel connection is a static one-time assembly mode generally without disassembly during operation; before parallel connection is implemented, the storage capacity of the batteries is properly reduced, the voltage is reduced to a preset standard value of parallel connection, the voltage difference of battery components is reduced, the internal resistance is higher, the condition of parallel connection is met, the circulating current value is much smaller, the production safety is improved, and the possibility of accidents is reduced. In addition, the battery sub-components in the parallel connection mode need to be independently detected and managed, otherwise, the battery sub-components fail due to large and sharp attenuation of the charge and discharge capacity of the whole battery pack and the system caused by insufficient charge and discharge due to long-term parallel unbalance of the battery components.

The power battery pack is a high-energy low-resistance active dynamic working component in the operating equipment environment, so that two finished battery packs cannot be directly connected in parallel under the non-static assembly condition. When the voltage platforms and capacities are different, direct parallel connection means that circulating current charging and discharging occur between battery packs, and when uncontrolled current is extremely large and continuous due to low battery impedance, internal loss and heat are serious and accumulated, and even the battery is damaged.

The protection management unit built in the finished battery pack component generally designs two independent charging and discharging working processes for the charging and discharging processes and manages the charging and discharging working processes according to corresponding standard processes, and the key point is to protect the over-range of the electrical characteristic parameters of the whole battery or single battery and not to intervene in the management of the detailed parameters in the charging and discharging operation steps and processes. The simple and rough direct parallel connection of multiple battery packs can lead to the battery packs being in an abnormal charging process or an abnormal discharging process and being uncontrolled, and the degree of the abnormality is directly determined by the difference of the electrical parameters such as the charge state of the battery packs. If this uncontrolled direct parallel connection occurs multiple times, it will result in accelerated cell failure or rejection.

At present, in the prior art, finished battery packs of electric equipment are connected in parallel in two ways, one of which is that a breaking switching way is directly adopted, for example, an air switch is selected for manual breaking switching, and for example, a direct current relay or a contactor is adopted for breaking switching. The system works in a cold backup switching mode, namely, the switch contacts are used for respectively switching and communicating one group of batteries to enter a working state to realize online charging and discharging, the other group of batteries is in a cold backup standby state, and the system can also be pulled out from one group of batteries to be placed in other equipment or switched to charge for standby. The system is switched without battery power supply at the moment, so the system is switched only in the closed state of the equipment generally. In this mode, only one group of batteries in discharge operation is always available, i.e. the cold backup switching operation mode. Alternatively, an external parallel circuit unit is used to connect or join the logic parallel ideal diode switch Oring-SW, also called "OR" switch. The parallel connection of two groups of batteries is realized by adopting a countercurrent closing technology. The OR switch is composed of a field effect transistor, a body diode, a detection circuit and a control circuit, and the basic control and switch logic is as follows: the diode works by current at the initial stage of power-up, the field effect transistor is immediately started to conduct when the forward current is larger, the forward conduction voltage drop and the loss are reduced, and the field effect transistor is closed when the forward current is reduced and the controlled conduction voltage drop is lower than 30 mv. Particularly, when the detection circuit prompts that the current short circuit or the reverse conduction occurs, the control circuit quickly closes the field effect tube to cut off the low-resistance branch, so that the forward short circuit protection is realized, and the real-time blocking of the reverse current is also realized. The circuit connection adopts an 'or' on 'switch to be connected with the battery pack in series and then connected in parallel to form a parallel discharge system, at the moment, the battery pack which generates instantaneous reverse current, namely reverse charging current, in the system is blocked by the' or 'on' switch connected with the battery pack in series, so that the battery pack with strong battery voltage and load capacity is discharged, and the voltage and current competition on-off temperature backup redundancy working mode is completed. In fact, in the working mode, most of the time, the battery packs which generally provide current to participate in discharging are only one group, other batteries do not participate in discharging, and warm backup is in standby; the discharge is performed simultaneously in a short time under the condition of equal parameters and simultaneously in a short time under the condition of large load, but the discharge current is not controlled and is determined by the difference between the internal dynamic electrical performance parameters, and the small difference can cause the imbalance of large discharge current among the battery packs or the discharge of partial battery packs.

In the prior art, although a protection board BPU is designed in the power battery pack, for a single-port battery pack, a charging port C and a discharging port D are combined into a battery output P port, and opposite series charge-discharge field effect tubes QC and QD are adopted to control opening and closing and realize overcharge-overdischarge protection shutdown; the field effect transistors charged and discharged in the battery pack are in a low-resistance low-loss conduction working state within a preset normal working parameter range, and the battery pack is effectively discharged by matching with external electric equipment; at the moment, the port of the battery pack is in a low-impedance opening and closing state, so that the battery pack can discharge and can also receive the charging electromotive force and the charging current of other batteries or active elements connected in parallel; continuous uncontrolled high current charging can cause the internal of the battery pack to accumulate heat and heat up sharply or locally with high heat, resulting in failure or even damage.

In the prior art, a power battery discharge large system is formed by forming pre-assembled components into blocks or layers and then splicing the blocks or layers into a large system energy pack system, and the system fault rate caused by element faults is high and the maintenance is difficult.

Disclosure of Invention

The invention aims to solve the technical problem of providing a multi-battery pack dynamic hot standby redundant parallel discharge operation system and method aiming at the technical defect that the multi-battery packs in the prior art cannot be simultaneously operated in a hot standby redundant parallel mode.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a multi-battery pack parallel discharge operation system comprises a plurality of controlled discharge battery packs BRPi, i is not less than 2; all positive ends of the controlled discharge battery packs are connected with each other, all negative ends of the controlled discharge battery packs are connected with each other, and the controlled discharge battery packs and the discharge loads form a multi-battery-pack parallel discharge operation system; the controlled discharge battery pack is a homogeneous type discharge battery pack;

the electric type controlled discharge battery pack refers to that the basic electric type parameters of the electric type controlled discharge battery pack are controlled within an effective preset range, namely, the discharge output voltage DhVo/Vset and the discharge output current DhIo/Iset; the equivalent impedance DhRo of the discharge output of the extended electrical parameter and the voltage volt-ampere power DhPO of the discharge output are controlled; its associated electrical type parameter current limit is controlled in association with the battery voltage, and the volt-ampere power is controlled in association with the battery voltage.

Furthermore, the system is provided with a communication bus BPC, a discharge identification port SCD and address interfaces ADR; the system is provided with a multi-battery pack discharge system controller DMU; the system uniformly presets a discharge operation rated voltage Vset and a discharge operation rated current limiting Iset; the system is provided with a discharge regulation algorithm, and discharge droop volt-ampere output parameters are set; the system is provided with a discharging current-sharing bus interface SBUS; the electric type controlled discharge battery BRP is a built-in switch conversion discharge battery.

Furthermore, within the effective discharge working range set by the system, the built-in switch conversion discharge battery pack is a built-in buck switch conversion discharge battery pack, or a built-in boost switch conversion discharge battery pack, or a built-in buck-boost switch conversion discharge battery pack.

Furthermore, configuring the corresponding resistance of each battery pack address interface ADRi according to the coding serial number; the system controller DMU is connected with each battery pack communication bus BPC; establishing a serial communication protocol of a parallel discharge system to send and receive information and instructions; and configuring a discharge identification signal or a sending protocol associated with the controller DMU in the battery pack.

Furthermore, the discharging system controller DMU exchanges the states and parameters of all battery packs with the system communication bus BPC; the DMU calculates default and running preset voltages of the discharge system according to a design configuration algorithm; the DMU finely adjusts the preset voltage according to a droop volt-ampere characteristic algorithm configured by the design; the DMU is connected with a system communication bus BPC and issues commands according to broadcasting or single addresses; and the DMU analyzes and counts the characteristic quantity of the discharge system according to the design configuration function and algorithm.

Further, the system preset power-up default voltage Vset1 is the battery pack constant voltage charging value Vcc; the system preset operation dynamic voltage Vset1 is a system planned operation value Vsep.

Further, the system preset optimal discharge voltage Vset0 is slightly larger than Vset 1; the system preset discharge voltage Vset2 is slightly less than Vset 1; the Vset0, Vset2 and Vset1 difference is set to Vsd ═ 1-5)% Vcc.

Furthermore, uniform discharge output volt-ampere droop characteristic parameters and an application range limit value are selected, wherein Vout is Vset-Krate Iout, Vdu is more than Vout and is more than Vdl; relative to the rated voltage Vnom, the voltage value range is Vdu: (95-115)% Vnom or (85-100)% Vcc, Vdl: (85-95)% Vnom or (75-85)% Vcc; relative to the rated current Inom, the droop slope Krate ═ V/Inom (0.5-1.5); and all the battery packs in the system are connected in parallel according to the unified preset dynamic characteristic impedance matching and self-adaptive hot standby balanced discharge.

Further, the system battery pack operation current limit is defined by the ratio of three-gear controlled values, namely K1 or K0 or K2;

the K1 is 1, and the battery pack preset current limit Ids is K1 Iset;

3> K0>1, specifying a preset battery pack current limit Ids ═ K0 ═ Iset;

the 1> K2>0.5, and specifies a preset current limit Ids ═ K2 × (Iset) of the battery pack;

presetting specific current limiting IDs of each battery pack, and respectively referring to: the battery pack is correspondingly and autonomously configured with a power-on value and a current-sharing full value according to the full parameter; or designing default values according to hardware addresses, and identifying and configuring the battery pack according to the addresses; or setting a corresponding address according to the menu by referring to the controller to issue a configuration instruction;

and if the voltage of the battery pack string is lower than a preset value, automatically adjusting down the configuration value.

The parallel discharge method of any one of the above systems, comprising the steps of:

1) selecting an effective discharge working range of the electric type controlled discharge battery pack, wherein the effective discharge working range comprises a rated value, a maximum value, a minimum value and a power-on default value; in a specified effective discharge working range, one-way discharge works, the discharge output volt-ampere characteristic is in two modes and corresponds to a preset current-limiting load point;

1-1) when the load is smaller than the corresponding preset current-limiting load point, the load is a constant-voltage section;

1-2) when the load is larger than the corresponding preset current-limiting load point, the load is a constant current section;

the constant voltage and constant current preset value can be a certain value point in an effective discharge working range appointed by a system memory or a communication protocol, the maximum constant voltage and constant current value is selected as a relative ratio of rated voltage and current, and the value selection range is 100 plus 125%.

Further, the method comprises the following steps:

2) the discharging system controller is connected with all the battery pack current sharing interfaces SBUS in parallel;

issuing a current-sharing starting working current lower limit value point by a system controller DMU;

issuing a current sharing temporary shutdown working voltage upper limit point by a system controller DMU;

each battery pack dynamically adjusts discharge voltage in a low-pass fine mode and adjusts current in a follow-up mode by utilizing a current-sharing bus signal, an embedded low-power differential discharge algorithm and a double-ring mode, and current sharing is achieved.

Further, the method comprises the following steps:

3) selecting an effective discharge output working range of the built-in conversion discharge battery pack, namely the high-efficiency electric type controlled discharge battery pack;

3-1) in the working state of voltage rising and reduction transformation, the output voltage of the effective working range is up to the preset discharge voltage but not more than the rated voltage upper limit, and is down to the rated voltage lower limit or the current limit is close to zero;

3-2) in the boosting conversion working state, the output voltage in the effective working range is from the internal string voltage of the battery pack to the preset discharging voltage but is less than the maximum discharging rated voltage value;

3-3) in the step-down conversion working state, the output voltage of the effective working range is two sections, the first section is a rated section which is from the voltage of the internal group of the battery pack and is as low as the preset discharging voltage but not lower than the lower limit of the rated voltage, and the second section is a current-limiting section which is used for continuously limiting the current and reducing the voltage to be lower than the preset voltage and gradually reducing the voltage to zero value for output when the current is limited or overloaded during discharging output;

three built-in conversion battery packs with different conversion types of voltage boosting, voltage reducing and voltage boosting have different effective discharge working ranges; the built-in conversion battery pack is controlled in discharge voltage and current within an effective discharge working range, works in a constant voltage current limiting and constant current voltage reducing two-stage mode, and the impedance of an output port is correspondingly controlled and is an equivalent impedance value corresponding to preset or rated voltage and current.

Further, the method comprises the following steps:

4) the multi-battery pack parallel discharge system controller issues a command and sends a system preset optimal discharge voltage Vset0 to a selected partial battery pack, namely Vset1+ Vsd; the independent preset value Vset0 in the system is slightly higher, so that the partial battery pack enters a priority discharge mode, namely, the partial battery pack is preferentially discharged in a maximum rated current limiting mode, the discharge power energy is provided by the current larger than the average current of the system, the residual capacity is reserved according to the preset value and is discharged to be close to the termination voltage or the residual capacity, the partial battery pack becomes the battery pack which preferentially and rapidly releases the residual capacity in the system, the system is conveniently designed according to the principle that the battery capacity is low and the priority discharge is realized, and the partial battery pack is designed to exit or wait for charging in the discharge system.

Further, the method comprises the following steps:

5) the multi-battery pack parallel discharge system controller issues a command and sends a system preset discharge voltage Vset2 to a selected partial battery pack, namely Vset 1-Vsd; forming a second preset value Vset2 which is slightly lower than the preset value Vset1, and enabling part of battery packs set in the system to enter a secondary standby mode;

6) the multi-battery pack parallel discharge system controller issues a command, and sends a system preset discharge voltage Vset1 to the battery packs which do not belong to the substep 4) and the substep 5) to form a system operation dynamic voltage Vset1 equal to Vsep, namely a planning operation value, until the over-discharge protection stops discharging.

The system and the method for the parallel discharge operation of the multiple battery packs have the following beneficial effects:

the invention utilizes the composite open-close protection and the built-in conversion discharge mechanism of the electric type controlled discharge battery pack to ensure that the battery pack has the specific controlled electric type characteristic and becomes a programmable constant voltage constant current mechanismVoltammetric apparatusAnd droop volt-ampere characteristics, unidirectional discharge, autonomous current sharing and intelligent programmable modular equipment, so that the hot standby redundant parallel discharge operation of a plurality of battery packs is realized. Especially, through power switch conversion and control, unexpected reverse current is avoided, power conversion output specific voltage current and impedance control and autonomous dynamic current sharing are realized, so that each battery pack in the system can realize unidirectional output, adjustable constant voltage stabilization or linear droop, adjustable constant current limiting and autonomous current sharing discharge, and the function of multi-battery pack dynamic hot standby redundant parallel current sharing discharge is achieved. Therefore, the system rating can reach the sum of the rated discharge currents of all the multiple battery packs, and a modular hot standby redundant parallel discharge system is formed.

The invention adopts a removable multi-modular parallel system, has good performance in the whole parameter range, is applicable in the whole scene, has clear method principle, easy realization and simple control, and the implementation scheme has simple and convenient type selection, simple specification and variety and low cost. Therefore, the performance of the power parallel discharge system is greatly improved, the cost performance is high, the power parallel discharge system can adapt to various working environments, the design is simpler and more efficient, and the system has extremely high availability, maintainability and reliability in operation.

Drawings

FIG. 1 is a schematic view of the interior of a common positive/negative terminal single port protective plate of a conventional battery pack of the prior art;

FIG. 2 is a schematic diagram of a prior art switch switching implementation with two sets of common positive/negative terminal battery packs connected in parallel;

FIG. 3 is a schematic diagram of a prior art or on/off switch for parallel connection of two sets of common positive/negative terminal battery packs;

FIG. 4 is a schematic diagram of a parallel discharge circuit of the common positive side single port boost converter battery pack of the present invention;

FIG. 5 is a schematic diagram of a parallel discharge circuit of the common-negative single-port buck-boost conversion battery pack according to the present invention;

FIG. 6 is a graph showing the ampere droop characteristics of the current V-A volts output by the present invention;

FIG. 7 is a schematic diagram of droop characteristics of the present invention for a V-C volt ampere-hour conversion output voltage capability;

FIG. 8 is a schematic diagram of the current limiting three preset features of the present invention for a transform output operation;

FIG. 9 is a circuit example 1 of an application scheme of the multi-battery parallel discharge system of the present invention;

FIG. 10 is a circuit example 2 of an application scheme of the multi-battery parallel discharge system of the present invention;

FIG. 11 is a circuit example 3 of an application scheme of the multi-battery parallel discharge system of the present invention;

FIG. 12 is a circuit example 4 of an application scheme of the multi-battery parallel discharge system of the present invention;

fig. 13 is a flowchart for controlling the operation of the multi-battery parallel discharge system of the present invention.

Detailed Description

The invention relates to a multi-battery pack parallel discharge operation system, which comprises a plurality of controlled discharge battery packs BRPi, i ≧ 2; all positive ends of the controlled discharge battery packs are connected with each other, all negative ends of the controlled discharge battery packs are connected with each other, and the controlled discharge battery packs and the discharge loads form a multi-battery-pack parallel discharge operation system;

the controlled discharge battery pack is a homogeneous type discharge battery pack;

The operation system is characterized in that:

the system is provided with a communication bus BPC, a discharge identification port SCD and address interfaces ADR;

the system is provided with a multi-battery pack discharge system controller DMU;

the system uniformly presets a discharge operation rated voltage Vset and a discharge operation rated current limiting Iset;

the system is provided with a discharge regulation algorithm, and discharge droop volt-ampere output parameters are set;

the system is provided with a discharging current-sharing bus interface SBUS;

the electric type controlled discharge battery BRP is a built-in switch conversion discharge battery.

The electric controlled battery pack is characterized in that a power inductor L is arranged inside the electric controlled battery pack, a power switch field effect tube QB is arranged between the inductor element L and the battery pack string B end, a power switch field effect tube QP is arranged between the inductor element L and the battery output P end, the inductor L is connected in series between the battery pack string B end and the battery output P end through a switch and corresponds to follow current through a diode or a field effect tube, a high-frequency filter capacitor C is connected between the battery pack string B end and the positive and negative poles on the two sides of the battery output P end to form a switch adjusting unit, and the battery output P end, namely the battery discharge voltage, the discharge current and the discharge equivalent impedance are controlled and adjusted.

The operation system is characterized in that:

in the effective discharge working range set by the system, the built-in switch conversion discharge battery pack is a built-in buck switch conversion discharge battery pack, or a built-in boost switch conversion discharge battery pack, or a built-in buck-boost switch conversion discharge battery pack.

The operation system is characterized in that:

configuring corresponding resistors of address interfaces ADRi of each battery pack according to the coding serial numbers;the system controller DMU is connected with each battery pack communication bus BPC; establishing a serial communication protocol of a parallel discharge system to send and receive information and instructions; configuring a discharge identification signal associated with the in-battery controller DMUOr issue the protocol。

The operation system is characterized in that:

the DMU exchanges the states and parameters of all battery packs with a system communication bus BPC; the DMU calculates default and running preset voltages of the discharge system according to a design configuration algorithm; the DMU is configured according to designVoltammetric apparatusFine-tuning a preset voltage by using a droop volt-ampere characteristic algorithm; the DMU is connected with a system communication bus BPC and issues commands according to broadcasting or single addresses; and the DMU analyzes and counts the characteristic quantity of the discharge system according to the design configuration function and algorithm.

The operation system is characterized in that:

the system preset power-on default voltage Vset1 is a constant voltage charging value Vcc of the battery pack; the system preset operation dynamic voltage Vset1 is a system planned operation value Vsep.

The Vsep is obtained by averaging and calculating voltage parameters of all parallel battery packs in the system within an appointed effective working range of the system, and the algorithm comprises the following steps: rated value, average value, median value, mean square value and residual ampere-hour weight average value; set by the system design time.

The operation system is characterized in that:

the system preset optimal discharge voltage Vset0 is slightly larger than Vset 1; the system preset discharge voltage Vset2 is slightly less than Vset 1; the Vset0, Vset2 and Vset1 difference is set to Vsd ═ 1-5)% Vcc.

The operation system is characterized in that: selecting a uniform discharge output volt-ampere droop characteristic parameter and an application range limit value,

Vout-Vset-Krate Iout, Vdu > Vout > Vdl; relative to the rated voltage Vnom, the voltage value range is Vdu: (95-115)% Vnom or (85-100)% Vcc, Vdl: (85-95)% Vnom or (75-85)% Vcc; relative to the rated current Inom, the droop slope Krate ═ V/Inom (0.5-1.5); and all the battery packs in the system are connected in parallel according to the unified preset dynamic characteristic impedance matching and self-adaptive hot standby balanced discharge.

The operation system is characterized in that: the system battery pack operation current limit is defined by the ratio K1 of three-gear controlled values; the K1 is 1, and the battery pack preset current limit Ids is K1 Iset;

presetting specific current limiting IDs of each battery pack, and respectively referring to:

the battery pack is correspondingly and autonomously configured with a power-on value and a current-sharing full value according to the full parameter;

the system designs a default value according to a hardware address, and the battery pack is configured according to address identification;

the system controller sets a corresponding address according to the menu to issue a configuration instruction;

and if the voltage of the battery pack string is lower than the preset value, automatically adjusting down the configuration value K2.

The operation system is characterized in that: the system battery pack operation current limit is defined by the ratio K0 of three-gear controlled values; 3> K0>1, specifying a preset battery pack current limit Ids ═ K0 ═ Iset;

The operation system is characterized in that: the system battery pack operation current limit is defined by the ratio K2 of three-gear controlled values; the 1> K2>0.5, and specifies a preset current limit Ids ═ K2 × (Iset) of the battery pack;

Referring to fig. 13, the method of operating the parallel discharge system according to the above includes the steps of:

selecting an effective discharge working range including a rated value, a maximum value, a minimum value and a power-on default value for the electric type controlled discharge battery pack; in the appointed effective discharge working range, the unidirectional discharge working is carried out, the discharge output volt-ampere characteristic is in two modes, a current-limiting load point is correspondingly preset, a constant voltage section is arranged when the load is smaller than the current-limiting load point, a constant current section is arranged when the load is larger than the current-limiting load point, the constant voltage constant current preset value can be appointed to a certain value point in the effective discharge working range by a system memory or a communication protocol, the maximum constant voltage constant current value is selected as the relevant ratio of rated voltage and current, and the selected value range is 100 plus 125%.

The operation method of the electric type controlled discharge battery pack comprises the steps of configuring default values according to rated current-limiting load points during power-on, receiving current-limiting load point adjusting instructions of the discharge controller DMU and assigning values, detecting discharge voltage and discharge current during operation, adjusting the pulse width and the working mode of the switch according to constant voltage characteristics when the current-limiting load points are judged to be smaller than preset load points, and adjusting the pulse width and the working mode of the switch according to constant current characteristics when the current-limiting load points are judged to be larger than the preset load points.

The operation method of the parallel discharge system comprises the following steps,

selecting one of the following operational amplifier distribution average value circuit, operational amplifier distribution maximum value circuit, software distribution average value circuit or system controller DMU software to design the current sharing signal SBUS of the discharge system:

the discharging system controller is connected with all the battery pack current sharing interfaces SBUS in parallel;

The operation method of the parallel discharge system further comprises,

the built-in conversion discharge battery pack is a high-efficiency electric type controlled discharge battery pack, and the effective discharge output working range is as follows:

the output voltage of the effective working range of the buck-boost conversion is higher than the preset discharge voltage but lower than the rated voltage upper limit, lower than the rated voltage lower limit or the current limit is close to zero;

the output voltage of the effective working range of the boost conversion is from the voltage of the internal string of the battery pack to a preset discharge voltage but is less than the maximum discharge rated voltage value;

the voltage reduction and transformation effective working range output voltage is two sections, the first section is a rated section and is from the internal string voltage of the battery pack from low to the preset discharge voltage but higher than the lower limit of the rated voltage, and the second section is a current limiting section and is used for continuously limiting the current and reducing the voltage to be lower than the preset voltage and gradually reducing the voltage to zero value for output when the current is limited or overloaded by discharge output;

three built-in conversion battery packs with different conversion types of voltage boosting, voltage reducing and voltage boosting have different effective discharge working ranges; the built-in conversion battery pack is controlled in the effective discharge working range, the discharge voltage and current are controlled, the built-in conversion battery pack works in a constant voltage current limiting mode and a constant current voltage reducing mode, and the impedance of an output port is correspondingly in a controlled state and is an equivalent impedance value corresponding to preset or rated voltage and current. This is an intra-group judgment conversion mode to determine the effective discharge operating range.

The operation method of the parallel discharge system further comprises,

the multi-battery pack parallel discharge system controller issues a command and sends a system preset optimal discharge voltage Vset0 to a selected partial battery pack, namely Vset1+ Vsd; forming a slightly higher independent preset value Vset0 in the system, and enabling the partial battery pack to enter a priority discharge mode;

when the discharging system selects the low-capacity battery pack priority discharging mode, part of the battery packs receive a preset priority discharging instruction, the battery packs are discharged in a maximum rated current limiting mode according to a priority discharging voltage Vset0 slightly higher than Vset1, discharging power energy is provided by average current larger than the system, residual capacity is reserved according to a preset value and is discharged to be close to a termination voltage or the residual capacity, the battery packs with the residual capacity released in the system preferentially and quickly are formed, the system is conveniently designed according to the low-priority discharging principle of the battery capacity, and therefore the fact that part of the battery packs quit or wait to be charged in the discharging system is facilitated; that is, whether the current battery pack is lower than the voltage of the other battery packs discharging is judged, if yes, the battery pack enters the optimal discharge mode according to the preset optimal discharge voltage Vset 0; the current battery pack becomes a low-voltage priority discharge object, quickly releases the battery pack with the residual capacity, and then exits discharge in advance or enters a state to be charged;

when the discharging system selects a high-capacity battery pack priority discharging mode, partial battery packs receive a preset optimal discharging instruction, the battery packs are discharged in a maximum rated current limiting mode according to an optimal discharging voltage Vset0 slightly higher than Vset1 to provide discharging power energy with the average current larger than the system average current, tolerance capacity is reserved according to a preset battery pack terminal voltage value, and the battery packs are discharged until the battery pack terminal voltage is close to the system average voltage or the capacity is close to the discharging battery capacity median value, so that each battery in the system is in a balanced state with the close capacity, and the modularized balanced control of the system is facilitated; that is, it is determined whether the present battery pack is higher than the voltage at the other battery pack terminal being discharged, and if so, the optimum discharge mode is entered at the preset optimum discharge voltage Vset 0.

The operation method of the parallel discharge system further comprises,

the multi-battery pack parallel discharge system controller issues a command and sends a system preset discharge voltage Vset2 to a selected partial battery pack, namely Vset 1-Vsd; forming a second preset value Vset2 which is slightly lower than the preset value Vset1, and enabling part of battery packs set in the system to enter a secondary standby mode;

the multi-battery pack parallel discharge system controller issues a command, and sends a system preset discharge voltage Vset1 to the battery packs which do not belong to the substep 4) and the substep 5) to form a system operation dynamic voltage Vset1 equal to Vsep, namely a planning operation value, until the over-discharge protection stops discharging.

When the discharge system selects the secondary standby discharge mode of the high-capacity battery pack, part of the battery packs receive a pre-device discharge instruction, the battery packs operate in a mode that the secondary voltage Vset2 slightly lower than Vset1 or low current secondary discharge or backup discharge is carried out, and the partial battery packs in the system run in a hot standby discharge mode and run in a low-power standby mode; and forming a low-consumption economic operation mode of the parallel discharge system. That is, it is determined whether the present battery pack is higher than the voltage of the other battery pack terminals, and if so, the sub option discharge mode is entered at the preset sub option discharge voltage Vset 2.

When the discharging system selects the secondary discharging mode of the low-capacity battery pack, part of the battery packs receive a pre-device discharging instruction, the battery packs operate in a low-power consumption standby mode according to the optimal discharging voltage Vset2 slightly lower than Vset1, or secondary discharging or backup discharging at lower current, and the battery packs operate according to a preset battery pack terminal voltage value or reserved tolerance capacity until the battery pack terminal voltage is close to the average voltage of the system or the capacity is close to the median of the discharged battery capacity, so that each battery in the system is in a balanced state with the approximate capacity, and the modular balance control of the system is facilitated; that is, it is determined whether the present battery pack is lower than the terminal voltage of the other battery packs being discharged, and if so, the sub-optional discharge mode is entered by pressing the preset sub-optional discharge voltage Vset 2.

In the invention, each battery pack in the system is controlled in discharge output power type and adopts built-in conversion to regulate discharge; FIG. 4 is a schematic diagram of the parallel discharge of a built-in half-bridge boost-buck conversion discharge battery pack BRP-HB according to the present invention, and FIG. 5 is a schematic diagram of the parallel discharge of a built-in full-bridge boost-buck conversion discharge battery pack BRP-FB according to the present invention; due to the special power conversion performance of the built-in conversion regulator of the composite switching protection, the battery pack BRP has unidirectional discharge, and the output voltage, the current, the output power and the equivalent output impedance are controlled states, so that the inherent uncontrolled characteristics of abnormal low resistance, reflux, overcurrent and the like of the original battery pack are avoided, the controlled parallel connection of multiple battery packs can effectively operate, and a modular hot standby redundant parallel connection discharge system is formed.

Fig. 6 is a schematic diagram of a working relationship between an effective discharge output voltage and a battery string voltage during buck-boost, boost-buck conversion of the internal conversion discharge battery pack, three different conversion types and different effective discharge output working ranges are shown from left to right, and a schematic diagram of a current volt-ampere droop characteristic of the internal conversion discharge output voltage is shown on the lower right side of each diagram; the built-in half-bridge boost conversion parallel discharge electric type battery pack BRP-HB has good performance and low cost, and the built-in full-bridge boost conversion parallel discharge electric type battery pack BRP-FB has excellent performance and high cost performance.

Fig. 7 is a schematic diagram of the volt ampere-hour regulation characteristics of the output voltage V and the capacity C of the internal conversion discharge battery pack of the present invention, where vlp and Vnup are upper and lower limit values of the effective working area of the battery voltage, and Vnup are upper and lower limit values of friendly applications; in a high-value region of a battery voltage platform, a system can be configured with preset rated voltage outputs Vset1[ Vset0 and Vset2] according to address unification or grouping, in a middle and rear voltage region, droop adjusting characteristics are configured according to droop characteristic values [ Vk and Krate ], in a rear voltage region, the battery is subjected to current limiting and voltage reduction according to a regulated value, and when the upper and lower limit values of an effective range are exceeded, internal resistance is reduced until a battery pack has low-resistance characteristics; when the voltage V and the capacity C of the battery are lower than the preset values, the battery adjusts the output voltage to be controlled volt ampere-hour output characteristics according to the convention curve shown in the attached figure 7.

Fig. 8 is a schematic diagram of three-stage controlled characteristics of an output current-limiting circuit of a battery pack with a built-in conversion discharge according to the present invention, in which it can be seen that, in a rated region, generally, Iset is preset according to Inom discharge current with reference to a rated capacity of a battery, K1 is 1, and in a low-voltage operating region where a battery voltage is lower than a nominal value Vnom, the voltage is proportionally reduced to K2 of 0.5-0.95, while in a high-value region of a battery voltage platform, i.e., in a region where [ Vnom, Vnup ] or less is agreed, a system is proportionally increased to K0 of 1-3 according to a design configuration, and discharge operates with high-rate large current.

Battery embodiment 1 for a multi-battery dynamic hot standby redundant parallel discharge operation, as shown in fig. 9; a built-in half-bridge boosting discharge battery pack BRP-HB is adopted, and 2 48V16Ah battery modules are adopted to form a hot standby redundant parallel discharge system for an urban express professional electric two-wheeled vehicle;

battery pack example 2 for multi-battery pack dynamic hot standby redundant parallel discharge operation, as shown in fig. 10; a built-in full-bridge buck-boost discharge battery pack BRP-FB is adopted, and 3 battery modules of 48V16Ah are adopted to form a hot standby redundant parallel discharge system for the cross-country sports electric motorcycle;

battery pack example 3 for a multi-battery pack dynamic hot standby redundant parallel discharge operation, as shown in fig. 11; a built-in full-bridge buck-boost discharge battery pack BRP-FB is adopted, and 12 48V16Ah battery modules are adopted to form a hot standby redundant parallel discharge system for a 48V communication base station;

battery embodiment 4 for a multi-battery dynamic hot standby redundant parallel discharge operation, as shown in fig. 12; a built-in full-bridge buck-boost discharge battery pack BRP-FB is adopted, and 20 240V3Ah battery modules are adopted to form a parallel discharge system for a 240V small-sized data center.

Embodiments of the present invention will be further described with reference to fig. 9-12.

Fig. 9 shows an embodiment 1 of the system for parallel discharge operation of multiple battery packs according to the present invention, which comprises:

a controlled electric battery pack BRPi, i is 1-2 to form a parallel discharge system;

all anodes P + of the battery pack are connected, and all cathodes P-of the battery pack are connected;

the BPC serial port is vacant, the SAD port of the battery pack address state is suspended, and the internal detection is a discharging mode;

the battery pack effective discharge operating range further includes:

nominal voltage: vnom ═ 48.0V, (+ 16.7%, -12.5%) Vnom;

nominal range: the upper limit Vnup is 56.0V, the lower limit Vnlp is 42.0V;

friendly application: upper bound Vnua ═ 51.0V, lower bound Vnla ═ 45.0V, ± (4-7)%;

the default preset voltage Vset1 is 54.6V, and the optimal playback preset voltage Vset0 is 56.0V;

selecting rated specifications of a power system load controller: 48V (39-58V)/15A;

selecting a built-in half-bridge boosting electric discharge battery pack BRP-HB;

selecting a battery pack voltage capacity rated specification of 48V16 Ah;

choose for use group battery electricity core, include: lithium iron phosphate LiFe or ternary lithium battery Li 3Y;

selecting rated current Inom as 15A and short-circuit protection current as 45A;

selecting a battery pack over-low discharge protection voltage Vpdl which is 41.0V;

selecting a V-A output volt-ampere section droop parameter arranged in the battery pack, comprising the following steps:

wherein, Vp and Ip are battery discharge voltage and current, and Vb is the internal string voltage of the battery pack.

Fig. 10 shows an embodiment 2 of the system for parallel discharge operation of multiple battery packs according to the present invention, which comprises:

a controlled electric battery pack BRPi, i is 1-3 to form a parallel discharge system;

selecting a monitor and all battery packs, wherein BPC and SAD are connected;

selecting a monitor and all battery packs, and connecting resistors Ri in series between BH and SAD;

selecting an effective discharge working range of the system and the battery pack, and further comprising:

nominal voltage: vnom ═ 48.0V, (+ 16.6%, -12.5%) Vnom;

nominal range: the upper limit Vnup is 56.0V, the lower limit Vnlp is 42.0V;

default preset voltage Vset1 ═ 54.6V;

selecting rated specifications of a power system load controller: 48V (39-58V);

selecting a battery pack voltage capacity rated specification of 48V16 Ah;

selecting a built-in full-bridge boost-buck piezoelectric discharge battery BRP-FB;

further: selecting an electric parameter voltage, current, ampere-hour and impedance built-in transformation and adjustment algorithm;

choose for use group battery electricity core, include: lithium iron phosphate LiFe, ternary lithium battery Li 3Y;

selecting a built-in rated discharge current of the battery pack, comprising:

selecting rated current as Inom-30A and short-circuit protection current as 60A;

selecting a V-A output volt-ampere droop parameter in the battery pack, comprising the following steps:

wherein Vp and Ip are battery discharge voltage and current, and Vb battery pack internal string voltage;

fig. 11 shows an embodiment 3 of the system for parallel discharge operation of multiple battery packs according to the present invention, which comprises:

a controlled electric battery pack BRPi, i is 1-12 to form a parallel discharge system;

selecting a monitor and all battery packs, wherein BPCs are connected and Sbus are connected;

selecting all battery packs, and connecting resistors Ri in series between P + and SAD;

nominal voltage: vnom ═ 48.0V, (+ 16.6%, -12.5%) Vnom;

nominal range: the upper limit Vnup is 56.0V, the lower limit Vnlp is 42.0V;

default preset voltage Vset1 ═ 54.6V;

the optimal preset discharge voltage Vset0 is 56.0V, and the standby preset discharge voltage Vset2 is 53.5V;

the preset voltage setting tolerance error is less than 0.3V, and the 1C load voltage is reduced by less than 0.5V;

selecting rated specifications of a power system load controller: 48V (39-59V);

selecting a battery pack voltage capacity rated specification of 48V16 Ah;

selecting a built-in half-bridge boosting electric discharge battery pack BRP-HB; further comprising:

selecting an algorithm and parameters corresponding to the electric type internal conversion regulation of the battery pack, voltage, current, ampere-hour and impedance regulation;

choose group battery electricity core for use as power new forms of energy type, include:

lithium iron phosphate LiFe, ternary lithium battery Li3Y, modified manganese lithium LiMn and nickel hydride NiH;

selecting a built-in rated discharge current of the battery pack, comprising:

selecting rated current Inom as 15A, and controlling program range as (10-100)%;

selecting short-time discharge current 30A, wherein the short-circuit protection current is 45A;

selecting a discharging system controller DUM1 to manage each battery pack; the method comprises the following steps:

collecting the voltage of the internal strings of each battery pack, and calculating the average value as a programming voltage Vsep;

collecting the working condition and current of each battery pack, calculating and outputting a system current sharing signal Sbus;

issuing a play-preferred Vset0 and a play-pre Vset2 instruction according to the menu selection and the corresponding address;

and issuing a current-limiting program control instruction of each battery pack according to the discharge current-limiting value broadcast of the menu system.

As shown in fig. 12, embodiment 4 of the system for parallel discharge operation of multiple battery packs according to the present invention comprises:

a controlled electric battery pack BRPi, i is 1-20 to form a parallel discharge system;

the current equalizing buses Sbus are connected;

the BPC serial port is vacant, the SAD state port is suspended, and the internal detection is a discharge mode;

nominal voltage: vnom 240.0V, range: 210-280V;

default preset voltage Vset1 ═ 275V;

selecting a load rated voltage specification of a power system: 240V (190-290V);

selecting a battery pack voltage capacity rated specification of 240V3 Ah;

selecting an electric core: lithium iron phosphate, ternary lithium battery, modified manganese lithium and nickel-hydrogen power;

selecting rated current Inom as 6A and short-circuit protection current as 12A;

selecting a battery pack over-low discharge protection voltage Vpdl which is 205.0V;

the common ranges for ternary lithium batteries Li3Y are: 65S (3.00-3.15) ═ 195-205V

The common ranges of lithium iron phosphate LiFe are: 75S (2.00-2.75) 150-205V

The common ranges of modified manganese lithium LiMn are: 65S (2.55-3.15) ═ 165-205V

The common ranges for the nickel-hydrogen power NiH are: 200S (0.90-1.03) ═ 180-205V

Vp.set＝Vset1； Vb>Vnom；

Vp.set＝Vb+10； Vnom>Vb>Vpdl；

In the embodiment 1, the battery packs in the parallel system are respectively connected with the positive end and the negative end of all the batteries in parallel; the parallel discharge of the system is realized by independently matching the voltage, the current, the impedance and the ampere-hour characteristics of the batteries in parallel depending on the built-in conversion discharge regulation characteristics of each battery and the built-in voltage-current electric type convention parameters; the system is simple and compatible with conventional wiring, and the parallel discharge performance of the system is greatly improved.

In embodiment 2, the battery packs in the parallel system are respectively connected in parallel with the positive and negative ends of all the batteries, the communication bus BPC of the parallel monitoring unit and all the battery packs, and the address state SAD port lines of all the monitoring and battery packs, and each unit is connected with the position resistor matched with each other through the in-place signal BHi; in the system, the address status bus SAD can decode all devices in the system and use the corresponding bit code values of H0_ B0000, H2_ B0010, H4_ B0100 and H8_ B1000 or combine them into an address bus code value, and the current bit low value devices in the system master control information to transmit and receive information; the method comprises the steps that built-in bidirectional full-bridge conversion topology buck-boost conversion is adopted, the battery pack takes Vset1 as a preset voltage, and built-in discharge droop volt-ampere characteristics are adopted to implement automatic output impedance characteristic matching current balance adjustment; the system is configured with a high-performance communication mode, and the discharge performance of the system is improved while the intelligent level is greatly improved.

In embodiment 3, the battery packs in the parallel system are respectively connected in parallel with the positive and negative ends of all the batteries, the parallel monitoring units, the communication buses BPC of all the battery packs, and the current equalizing buses Sbus of all the monitoring and battery packs, and the address states SADi of all the battery packs are connected with the matched position resistors Ri by P +; in the system, an address state bus can interpret corresponding slave position code values 01# -12# of all battery packs in the system, the monitoring default is used as main monitoring, built-in bidirectional full-bridge conversion topology buck-boost conversion is adopted, the battery packs use Vset1 as preset voltage, a discharging current equalizing bus Sbus is adopted, and built-in controllers of all battery packs automatically complete current equalizing self-regulation; the system is designed according to a standard modular system, and the interaction and the intellectualization of a system controller are realized, so that the system is a standard mode of a multi-battery pack intelligent parallel system.

In embodiment 4, the battery packs in the parallel system are respectively connected in parallel with the positive and negative ends of all the batteries, and are connected in parallel with the current equalizing buses Sbus of all the monitoring and battery packs, the communication buses BPC of all the battery packs are vacant, and the address states SADi of all the battery packs are suspended and identified as the discharge states; according to the system, built-in bidirectional full-bridge conversion topology buck-boost conversion is adopted, the Vset1 is used as a preset voltage of a battery pack, a discharging current-sharing bus Sbus is adopted, and built-in controllers of the battery packs automatically complete current-sharing self-regulation; the system adopts built-in preset voltage and current regulation and adopts a current-sharing bus to implement battery discharge current sharing, does not need to rely on communication, and is a hardware connection optimization mode of multi-battery-pack self-heating standby parallel operation.

As can be seen from the above description, in the present invention, the electric environment includes a single battery pack formed by battery packs with 24V, 36V, 48V, 60V, 72V, 110V, 220V, 240V, 400V or other voltages as rated operating voltages. The battery packs are used for providing power electricity for high power in equipment or systems, are designed according to a hot standby redundant parallel system, comprise a plurality of identical or approximately identical components, can adopt batteries with appointed effective discharge working range and controlled and matched electric type, comprise a built-in half-bridge boosting discharge regulation electric type battery BRP-HB, have good performance and low cost, are built-in full-bridge boosting and boosting voltage regulation electric type batteries BRP-FB and have excellent performance. For example, 2-3 batteries of 48V16Ah are connected in parallel on an electric motorcycle, 4-8 batteries of 48V16Ah are connected in parallel on a low-speed four-wheel vehicle to configure power supply, 12 batteries of 48V16Ah are connected in parallel on a standby direct-current power supply system of a communication base station of 48V, and 20 batteries of 240V3Ah are connected in parallel on a standby direct-current power supply system of a small data station of 240V. When the power energy supply system works, a modular working mode of multi-battery pack online dynamic hot standby redundant parallel discharge design is adopted, so that the performance of a huge battery hard pile formed by built-in series-parallel connection in the prior art is superior, the power energy supply system is more efficient and convenient than a conventional manual switch or static switch switching parallel connection mode, and a power parallel structure is popularized to multi-battery pack online autonomous dynamic hot standby redundant parallel connection. The system has the capabilities of immediate removal, online plugging and unplugging, field expansion and real-time replacement. Each battery pack in the system is controlled in electric mode, adopts built-in conversion to adjust discharge, and can discharge in parallel from main heat redundancy according to preset voltage, current limiting, volt-ampere droop slope and current-sharing bus control modes; in order to achieve a set target, for example, the system is selected according to a low-frequency time interval, distributed according to a voltage platform, distributed according to an average current, distributed according to the residual capacity of a battery, distributed according to the dynamic internal resistance of the battery, distributed according to the internal temperature rise of the battery and the like, the state, the discharge and the energy related information of the battery pack are transmitted through a communication address and a communication protocol, a mode and parameter adjusting instruction is sent, the dynamic hot standby redundancy parallel discharge of the multi-battery pack is achieved, the systematic high-level intelligent management is achieved, and therefore the defects in the prior art are overcome.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A multi-battery parallel discharge operation system is characterized in that,

the system comprises a plurality of controlled discharge battery packs BRPi, i ≧ 2; all positive ends of the controlled discharge battery packs are connected with each other, all negative ends of the controlled discharge battery packs are connected with each other, and the controlled discharge battery packs and the discharge loads form a multi-battery-pack parallel discharge operation system;

2. The operating system of claim 1, wherein:

the system is provided with a discharging current-sharing bus interface SBUS;

3. The operating system of claim 2, wherein:

and in the effective discharge working range set by the system, the built-in switch conversion discharge battery pack is a built-in voltage reduction switch conversion discharge battery pack.

4. The operating system of claim 2, wherein:

and in the effective discharge working range set by the system, the built-in switch conversion discharge battery pack is a built-in boost switch conversion discharge battery pack.

5. The operating system of claim 2, wherein:

and in the effective discharge working range set by the system, the built-in switch conversion discharge battery pack is a built-in buck-boost switch conversion discharge battery pack.

6. The operating system according to claim 3, 4 or 5, wherein:

the system configures the corresponding resistance of each battery pack address interface ADRi according to the coding serial number;

the system controller DMU is connected with each battery pack communication bus BPC;

establishing a serial communication protocol of a parallel discharge system to send and receive information and instructions;

configuring a discharge identification signal associated with the battery pack system controller DMUOr issue the protocol。

7. The operating system of claim 6, wherein:

the DMU exchanges the states and parameters of all battery packs with a system communication bus BPC;

the DMU calculates default and running preset voltages of the discharge system according to a design configuration algorithm;

the DMU finely adjusts the preset voltage according to a droop volt-ampere characteristic algorithm configured by the design;

the DMU is connected with a system communication bus BPC and issues commands according to broadcasting or single addresses;

and the DMU analyzes and counts the characteristic quantity of the discharge system according to the design configuration function and algorithm.

8. The operating system of claim 7, wherein:

the system preset power-on default voltage Vset1 is a constant voltage charging value Vcc of the battery pack;

the system preset operation dynamic voltage Vset1 is a system planned operation value Vsep.

9. The operating system of claim 8, wherein:

the system preset optimal discharge voltage Vset0 is slightly larger than Vset 1;

the system preset discharge voltage Vset2 is slightly less than Vset 1;

the Vset0, Vset2 and Vset1 difference is set to Vsd ═ 1-5)% Vcc.

10. The operating system of claim 9, wherein:

selecting a uniform discharge output volt-ampere droop characteristic parameter and an application range limit value,

Vout-Vset-Krate Iout, Vdu > Vout > Vdl; relative to the rated voltage Vnom, the voltage value range is Vdu: (95-115)% Vnom or (85-100)% Vcc, Vdl: (85-95)% Vnom or (75-85)% Vcc; relative to the rated current Inom, the droop slope Krate ═ V/Inom (0.5-1.5);

and all the battery packs in the system are connected in parallel according to the unified preset dynamic characteristic impedance matching and self-adaptive hot standby balanced discharge.

11. The operating system of claim 10, wherein:

the system battery pack operation current limit is defined by the ratio K1 of three-gear controlled values;

the K1 is 1, and the battery pack preset current limit Ids is K1 Iset;

and if the voltage of the battery pack string is lower than the preset value, automatically adjusting the configuration value to K2.

12. The operating system of claim 10, wherein:

the system battery pack operation current limit is defined by the ratio K0 of three-gear controlled values;

3> K0>1, specifying a preset battery pack current limit Ids ═ K0 ═ Iset;

13. The operating system of claim 10, wherein:

the system battery pack operation current limit is defined by the ratio K2 of three-gear controlled values;

14. The parallel discharge method according to any of claims 1 to 13, comprising the steps of:

15. The method of claim 14, comprising the steps of:

16. The method of claim 15, comprising the steps of:

3) selecting the effective discharge output working range of the built-in switch conversion discharge battery pack, namely the high-efficiency electric type controlled discharge battery pack;

3-1) when the buck-boost switch changes the working state, the output voltage in the effective working range is up to the preset discharge voltage but not more than the rated voltage upper limit, and is down to the rated voltage lower limit or the current limit is close to zero;

3-2) when the boost switch changes the working state, the output voltage in the effective working range is from the internal string voltage of the battery pack to the preset discharge voltage but is less than the maximum discharge rated voltage value;

3-3) when the voltage reduction switch changes the working state, the output voltage of the effective working range is two sections, the first section is a rated section which is from the voltage of the internal group of the battery pack and is as low as the preset voltage of discharging but not lower than the lower limit of the rated voltage, and the second section is a current limiting section which is used for continuously limiting the current and reducing the voltage to be lower than the preset voltage and gradually reducing the voltage to zero value for output when the current is limited or overloaded by discharging output;

17. The method of claim 16, comprising the steps of:

4) the multi-battery pack parallel discharge system controller issues a command and sends a system preset optimal discharge voltage Vset0 to a selected partial battery pack, namely Vset1+ Vsd; the independent preset value Vset0 in the system is slightly higher, so that the partial battery pack enters a priority discharge mode, namely, the partial battery pack is preferentially discharged in a maximum rated current limiting mode, the discharge power energy is provided by the current larger than the average current of the system, the residual capacity is reserved according to the preset value, the partial battery pack is discharged to be close to the termination voltage or the residual capacity, the partial battery pack becomes the battery pack which preferentially and quickly releases the residual capacity in the system, the system is conveniently designed according to the principle that the battery capacity is low and the priority discharge is realized, and the partial battery pack is designed to exit or wait for charging.

18. The method of claim 17, comprising the steps of: