CN105652106A - Comprehensive performance testing method and apparatus of energy storage system - Google Patents

Abstract

The invention discloses a comprehensive performance testing method and apparatus of an energy storage system. The method comprises: step one, charging and discharging are carried out on an energy storage unit in an energy storage system; step two, a working state parameter of the energy storage unit is collected and obtained; and step three, according to the working state parameter of the energy storage unit, a comprehensive performance testing result is generated by calculation. According to the method and apparatus, the energy storage system is divided into two levels: an energy storage unit and a battery group string. Battery group string state evaluation is carried out on a unit with an abnormal overall capacity index of the energy storage unit, so that the safe operation of the system can be guaranteed and the maintenance workload can be effectively reduced. The energy storage unit overall capacity index based on calibrated working condition data can reflect the healthy state of the energy storage unit. And various methods for evaluating a healthy state of a battery group string are provided from the perspectives of the battery service life, aging, and consistency.

Description

A kind of accumulator system all-round property testing method and device

Technical field

The present invention relates to power energy storage appraisal procedure, espespecially a kind of accumulator system all-round property testing method and device.

Background technology

Due to the fast development of wind-force generating and photovoltaic generation installation, Large Copacity accumulator system can smoothly fluctuate by scene with it, regulates the advantages such as scene output power curve, obtains and pay close attention to and develop. Ending 2013, the accumulative installation scale of China's energy storage project reaches 53.7MW (not comprising water-storage). But current put into operation energy-accumulating power station is all shorter for working time, service data accumulation is few, and equipment performance is grasped not enough by the personnel that run, and is unfavorable for ensureing the safety and economic operation of new energy power station. For above problem, herein to grasp for the purpose of Large Copacity accumulator system state of health, carry out the research of high-capacity lithium battery accumulator system state evaluating method.

Achievement in research domestic and international at present mainly concentrates on the performance of power train in vehicle application lithium cell and the assessment of state of health, such as SOH evaluation method, internal resistance identification technology and other performance researchs etc. For high-capacity lithium battery accumulator system, State Grid Corporation of China company standard Q/GDW676 " accumulator system access distribution network test specification " defines the grid-connected performance test methods of accumulator system, and the main technical indicator of accumulator system access distribution network, but the standard scope of application is various electrochemistry and Power Flow, its test method regulation is comparatively wide in range, and regulation is not made in each index technical requirements, it is not enough to instruct the Performance Evaluation of scale lithium cell accumulator system. In " the high capacity cell energy storage station battery technology specification " worked out, only to battery cell and battery modules dispatch from the factory and type approval test method and index request make regulation, for still can not with reference to execution at fortune energy-accumulating power station Performance Evaluation. The self performance indexs such as the capacity of scale accumulator system or unit itself, efficiency for charge-discharge and monomer consistence and evaluation studies is less, therefore, good evaluation test method be there is no for lithium cell and lithium cell group over-all properties.

Summary of the invention

There is no good evaluation test method in prior art for lithium cell and lithium cell group over-all properties, accumulator system is divided in order to two levels by the present invention, by many-side, accumulator system is carried out assessment test, obtains the over-all properties data of accumulator system.

For achieving the above object, the present invention proposes a kind of accumulator system all-round property testing method, described method comprises: step 1, and the energy-storage units in described accumulator system is carried out discharge and recharge; Step 2, gathers and obtains the working status parameter of described energy-storage units; Step 3, calculates according to the working status parameter of described energy-storage units and generates accumulator system all-round property testing result.

For achieving the above object, the present invention proposes a kind of accumulator system comprehensive performance test device, described device comprises: charge-discharge modules, for the energy-storage units in described accumulator system is carried out discharge and recharge; Parameter collection module, for gathering and obtain the working status parameter of described energy-storage units; Performance test module, calculates for the working status parameter according to described energy-storage units and generates accumulator system all-round property testing result.

Accumulator system is divided into two levels by the accumulator system all-round property testing method of the present invention and device, energy-storage units entirety and series of cells string, wherein energy-storage units whole volume index anomaly unit is carried out series of cells string state estimation, can safeguards system safe operation, and effectively reduce maintenance workload, based on the energy-storage units whole volume index demarcating floor data, energy-storage units state of health can be embodied, also propose the method for multiple assessment series of cells string state of health simultaneously from battery life, aging, consistence angle.

Accompanying drawing explanation

Accompanying drawing described herein is used to provide a further understanding of the present invention, forms the part of the application, does not form limitation of the invention. In the accompanying drawings:

Fig. 1 is the accumulator system all-round property testing method flow diagram of one embodiment of the invention.

Fig. 2 is the method flow diagram of the energy-storage units overall performance test of the present invention one specific embodiment.

Fig. 3 is the method flow diagram being tested accumulator system performance by energy efficiency of the present invention one specific embodiment.

Fig. 4 is the method flow diagram by internal resistance incremental testing accumulator system performance of the present invention one specific embodiment.

Fig. 5 is the method flow diagram being tested accumulator system performance by voltage extreme difference of the present invention one specific embodiment.

Fig. 6 is the method flow diagram being tested accumulator system performance by temperature extreme difference of the present invention one specific embodiment.

Fig. 7 is the accumulator system comprehensive performance test device structural representation of one embodiment of the invention.

Embodiment

Hereinafter coordinate better embodiment that is graphic and the present invention, set forth further the present invention and reach the technique means that predetermined goal of the invention takes.

In embodiments of the present invention, it relates to illustrate in advance to some terms at this:

Energy-storage units refers to and is made up of energy accumulation current converter and battery pile thereof, it is possible to as the unit that independent load or power supply are directly dispatched by energy storage sub-system supervisory system.

Series of cells string refers to and is made up of multiple battery cell series-parallel connection.

Fig. 1 is the accumulator system all-round property testing method flow diagram of one embodiment of the invention. As shown in Figure 1, the method comprises:

Step 1, carries out discharge and recharge to the energy-storage units in accumulator system;

Step 2, gathers and obtains the working status parameter of energy-storage units;

Step 3, calculates according to the working status parameter of energy-storage units and generates accumulator system all-round property testing result.

When the all-round property testing of accumulator system, cell in series of cells string in wherein energy-storage units, energy-storage units, series of cells string can be carried out performance test, obtain the over-all properties of accumulator system with this.Concrete grammar is as follows:

In one embodiment, the test of energy-storage units overall performance is first carried out.

According to electric automobile lithium battery correlative study achievement, the capacity of battery cell is decayed with the increase of cycle index, and therefore capacity is possible not only to the life-span directly embodying battery, can reflect the attenuation degree of battery simultaneously. From the angle of fortune dimension, capacity is the important parameter during energy-accumulating power station runs, and is also the important decision foundation safeguarded by battery. And the capacity of energy-storage units is relevant to each monomer capacity, but not being simple cumulative, but be subject to the impact of consistence, operation condition and balancing technique, namely capacity can also embody coherency state between battery cell.

Therefore the present invention selects capacity as the sole indicator of the overall state verification of energy-storage units, if the capacity of whole unit meets service requirements, then diagnoses no longer further.

Concrete, the testing method of energy-storage units overall performance is as follows:

When performing step 2, gather charging and start and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units.

As shown in Figure 2, when performing step 3, the step of the test result generating energy-storage units overall performance comprises:

Step 311, starts according to charging and electric discharge terminates the moment, and the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units, calculate the test capacity obtaining energy-storage units;

Step 312, according to the test capacity of the initial capacity of energy-storage units and energy-storage units, calculates the state of health obtaining energy-storage units, as shown in table 1, is energy-storage units capacity performance index threshold value, and wherein, E is the test capacity of energy-storage units, E₀For the initial capacity of energy-storage units.

Table 1 energy storage system capacity metrics-thresholds

In step 311, in order to consider energy-storage units battery and current transformer performance simultaneously, calculation of capacity data source gets AC side of converter parameter; For accurately calculating energy-storage units capacity performance index, generally choosing the data under demarcation operating mode as data source, to this, the formula calculating the test capacity utilization obtaining energy-storage units is as follows:

$E={\∫}_{t_0}^{t_1}u\left(t\right)i\left(t\right)\mathrm{dt};---\left(1\right)$

Wherein, E is the test capacity of energy-storage units, and it is for accumulator system is when demarcating, the electric energy that AC side of converter inputs or outputs when completely filling or completely put, and unit is Wh;

t₀For energy-storage battery is when demarcating, the start time of charging, unit is the second;

t₁For energy-storage battery is when demarcating, in the end moment of charging, unit is the second;

I (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous current value in journey, and unit is A;

U (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous voltage value in journey, and unit is V.

Except aforesaid energy-storage units capacity carrys out the method for test performance, the factor affecting high-capacity lithium battery energy-storage units state of health, from System's composition angle, has chemical composition change etc. in the mode of connection of cell quantity, series of cells in series of cells, battery cell; From applying working condition angle, there are charging/discharging voltage, charge-discharge magnification, environment for use, the discharge and recharge frequency and degree of depth etc.; From consistence angle, having consistence between consistence between battery cell, group, its consistence comprises voltage, temperature and state-of-charge consistence. The present invention, from high-capacity lithium battery energy-storage units failure mechanism, studies the energy-storage units state of health characterization parameter that various reason causes, therefrom selects representative index.

Form structure from scale lithium cell accumulator system, current transformer can influential system reliability, but its efficiency of conversion can not pass that great changes will take place usually in time, therefore substantially can not be had an impact by the charge-discharge performance of system. Accumulator system performance degradation reason is mainly from the degeneration of energy-storage battery performance. Therefore, it is necessary to the performance estimating method of series of cells string in accumulator system is carried out monographic study, form the energy storage lithium cell performance estimating method being applicable to engineer applied.

To this, the present invention proposes the modes such as the energy efficiency by calculating series of cells string in energy-storage units, series of cells string or internal resistance of cell increment, monomer battery voltage extreme difference, cell temperature extreme difference, test the performance of energy-storage units.

In the present embodiment, as follows by calculating the method for the energy efficiency test performance of series of cells string:

When performing step 2, the working status parameter of energy-storage units comprises: voltage, current instantaneous value in a certain series of cells string process of charging in energy-storage units, the voltage in discharge process, current instantaneous value.

As shown in Figure 3, when performing step 3, generate accumulator system all-round property testing result and comprise:

Step 321, according to voltage, current instantaneous value in series of cells string process of charging a certain in energy-storage units, the voltage in discharge process, current instantaneous value, calculates and obtains energy efficiency;

Step 322, according to energy efficiency, calculates the state of health obtaining a certain series of cells string, as shown in table 2, is energy efficiency metrics-thresholds, wherein, and ��_groupFor energy efficiency.

Table 2 energy efficiency metrics-thresholds

In step 321, the energy efficiency of series of cells string, both by the impact of consistence in series of cells string, also by the impact of the total internal resistance size of battery, is that the integration capability of battery embodies, and energy efficiency is when doing volume test, can obtain simultaneously, is convenient to estimation. Therefore, select energy efficiency as the key index evaluating scale energy storage lithium cell state of health, calculate the formula obtaining energy efficiency utilization as follows:

${\mathrm{\η}}_{\mathrm{group}}=\frac{{\∫V}_{\mathrm{dis}}\·I_{\mathrm{dis}}\mathrm{dt}}{\∫V_{\mathrm{cha}}\·I_{\mathrm{cha}}\mathrm{dt}}\·100\%;---\left(2\right)$

Wherein, ��_groupFor energy efficiency, zero dimension;

V_dis��I_disUnder demarcating operating mode, in discharge process, voltage, current instantaneous value;

V_cha��I_chaUnder demarcating operating mode, in process of charging, voltage, current instantaneous value;

T is electric discharge start time to electric discharge cut-off condition time used or charging start time to charging cut-off condition time used.

For energy efficiency, the energy efficiency of general new battery is about 98%, the energy efficiency of vehicle lithium battery module is also higher, but in high-capacity lithium battery accumulator system, magnanimity battery cell is difficult to accomplish good consistence, and namely the power efficiency threshold being applicable to engineer applied can be excellent higher than 80%.

In the present embodiment, from the aging angle of battery, it is proposed that the key index of the internal resistance incremental testing performance of battery. Internal resistance is divided into ohmic internal resistance and polarization resistance, and the life-span of ohmic internal resistance and battery is closely related, therefore selects internal resistance increment as another key index evaluating scale energy storage lithium cell state of health. As follows by calculating the method for the internal resistance incremental testing performance of series of cells string or battery:

When performing step 2, the working status parameter of energy-storage units comprises: in discharge process, the voltage change value of a certain series of cells string or battery and curent change value in energy-storage units.

As shown in Figure 4, when performing step 3, generate accumulator system all-round property testing result and comprise:

Step 331, according in discharge process, in energy-storage units, the voltage change value of a certain series of cells string or battery and curent change value, calculate and obtain a certain series of cells string or internal resistance of cell increment, and the formula of utilization is as follows:

�� R=R_discharge-R₀;(3)

R_discharge=�� U/ �� I; (4)

Wherein, �� R is internal resistance increment;

R₀For the internal resistance initial value of a certain series of cells string or battery;

R_dischargeFor in discharge process, the internal resistance value of a certain series of cells string or battery;

�� U is in discharge process, the voltage change value of a certain series of cells string or battery;

�� I is in discharge process, the curent change value of a certain series of cells string or battery.

The physical significance of publicity (3) is in discharge process, and electric current changes the pressure drop that the causes ratio with current change quantity. The inner walkway method of general battery is to battery short-time pulse electric current, then compares electric current with voltage changing value. In actual production system, it does not have short-time pulse electric current, therefore electric current is changed to by 0 the moment of non-zero, it is believed that be approximate short-time pulse electric current. The pressure drop produced when �� U herein is exactly curent change. Simultaneously, due in actual production system, the sampling of electric current and voltage is second level, and laboratory test internal resistance needs Millisecond curent change, therefore the internal resistance that measure here can accurately not think true internal resistance, but be possible for across comparison, so same operating mode is preferably selected down contrast.

Step 332, according to internal resistance increment, calculates the state of health obtaining a certain series of cells string or battery, as shown in table 3, is internal resistance increment metrics-thresholds, wherein, and R₀For the internal resistance initial value of a certain series of cells string or battery, �� R is internal resistance increment.

Table 3 internal resistance increment recommends threshold value

In the present embodiment, gather and the working status parameter of energy-storage units that obtains also comprises: in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value, cell temperature maximum and cell temperature minimum value.

Saying from the angle that directly can obtain from service data, battery with two side terminals is divided into voltage consistence and temperature consistency. Between battery cell, between consistence, group, consistence with the variable changed working time, can directly affect every performance of accumulator system, revises and if not carrying out intervening, then can aggravate the disadvantageous effect to system. Therefore using another two indices as series of cells string performance test of voltage extreme difference and temperature extreme difference.

As follows by the method for battery extreme difference test performance:

As shown in Figure 5, step 341, according to, in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value, calculate and obtain voltage extreme difference; Method of calculation are as follows:

�� V=V_max-V_min; (5)

Wherein, �� V is voltage extreme difference, V_maxFor monomer battery voltage maximum value in series of cells string, V_minFor monomer voltage minimum value in series of cells string.

Step 342, under a certain state-of-charge, calculates the voltage consistence result obtaining a certain series of cells string according to voltage extreme difference.

Specifically, in production run, the difference of cell voltage is mainly manifested in the impact that state-of-charge (SOC) is estimated result, therefore the influence degree of the difference of cell voltage, depends on and SOC brings great impact. According to field operation experiences and relevant criterion, the limits of error of SOC are 10%, therefore think that cell health state is " poor " when the SOC difference caused by voltage differences reaches 10%, it is believed that more than 5% is perfect condition.

According to the relation curve of ferric phosphate lithium cell open circuit voltage and state-of-charge, it is seen that when SOC two ends, the steeper slope of voltage rise, and more slow at charge and discharge platform district slope, therefore, for voltage consistence on the impact of SOC, answer segmented description, as shown in table 4.After battery operation to this SOC section, leave standstill the open circuit terminal voltage extreme difference threshold value after 1 hour.

Table 4 voltage consistence table

In another embodiment, as follows by the method for temperature extreme difference test performance:

As shown in Figure 6, step 351, according to, in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value, calculate and obtain temperature extreme difference; Method of calculation are as follows:

�� T=T_max-T_min; (6)

Wherein, �� T is voltage extreme difference, T_maxFor monomer battery voltage maximum value in series of cells string, T_minFor monomer voltage minimum value in series of cells string.

Step 352, calculates the voltage consistence result obtaining a certain series of cells string according to temperature extreme difference.

For temperature factor, according to wind-light storage Demonstration Station debug process, when maximum temperature difference is less than 5 degree, the impact of series of cells string performance can be ignored; Maximum temperature difference is greater than 5 degree, and when being less than 8 degree, battery need to avoid charge and discharge, in order to avoid affecting its life-span; When the temperature difference is greater than 8 degree, should be out of service immediately, and search reason, therefore temperature extreme difference consistence is as shown in table 5:

Table 5 temperature consistency table

To this, in the accumulator system that the present invention proposes, there are two kinds of forms in the performance state assessment data source of series of cells string, and one is daily service data, and two is demarcate floor data.

Service data can obtain the temperature of any instant battery cell in operational process, the voltage of battery cell, and charging and discharging currents, voltage, therefore can obtain internal resistance increment, voltage extreme difference, temperature extreme difference; But series of cells string state-of-charge is generally operational between 20%-80% in production run, can not obtain completely being full of the data put, therefore cannot obtain energy efficiency achievement data source. Therefore energy efficiency calculating data source should come from demarcation floor data.

Demarcating operating mode has two kinds of methods to realize, and one is by energy storage supervisory system or producer's local operation, and control energy-storage units operates in demarcation operating mode, reads desired data by monitoring cabinet on the spot; Two is carry out measuring at the external test set of energy-storage units, obtains charging and discharging currents voltage, obtains battery management system data simultaneously. These two kinds of methods can obtain all data sources of series of cells string state estimation. The advantage of the 2nd kind of method be energy efficiency, internal resistance increment calculating by the impact of the aspects such as producer's battery management system method of calculation, acquisition precision, data are more accurate.

Based on same invention design, the embodiment of the present invention additionally provides a kind of accumulator system all-round property testing method and device, as described in the following examples. The principle dealt with problems due to this device is similar to accumulator system all-round property testing method, and therefore the enforcement of this device see the enforcement of aforesaid method, can repeat part and repeat no more. Following used, term " unit " or " module " can realize the software of predetermined function and/or the combination of hardware. Although the device described by following examples realizes with software goodly, but hardware, or the realization of the combination of software and hardware is also possible and is conceived.

Fig. 7 is the accumulator system comprehensive performance test device structural representation of one embodiment of the invention, and described method comprises:

Charge-discharge modules 1, for carrying out discharge and recharge to the energy-storage units in accumulator system;

Parameter collection module 2, for gathering and obtain the working status parameter of energy-storage units;

Performance test module 3, calculates for the working status parameter according to energy-storage units and generates accumulator system all-round property testing result.

In one embodiment, parameter collection module 2, gathers and the working status parameter that obtains energy-storage units comprises: charging starts and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units.

Performance test module 3, generates accumulator system all-round property testing result and comprises:

Starting according to charging and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units, calculate the test capacity obtaining energy-storage units;

Initial capacity according to energy-storage units and the test capacity of energy-storage units, calculate the state of health obtaining energy-storage units, and wherein, E is the test capacity of energy-storage units, E₀For the initial capacity of energy-storage units;

Work as E > 90%E₀Time, it is standard state; Work as 80%E₀< E < 90%E₀Time, it is sub-health state; E < 80%E₀Time, it is unhealthy condition.

Wherein, the formula calculating the test capacity utilization obtaining energy-storage units is as follows:

$E={\&Integral;}_{t_0}^{t_1}u\left(t\right)i\left(t\right)\mathrm{dt};---\left(1\right)$

Wherein, E is the test capacity of energy-storage units, and it is for accumulator system is when demarcating, the electric energy that AC side of converter inputs or outputs when completely filling or completely put;

t₀For energy-storage battery is when demarcating, the start time of charging;

t₁For energy-storage battery is when demarcating, the end moment of charging;

I (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous current value in journey;

U (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous voltage value in journey.

In one embodiment, parameter collection module 2, gathers and the working status parameter that obtains energy-storage units comprises: voltage, current instantaneous value in a certain series of cells string process of charging in energy-storage units, the voltage in discharge process, current instantaneous value.

Performance test module 3, generates accumulator system all-round property testing result and comprises:

According to voltage, current instantaneous value in series of cells string process of charging a certain in energy-storage units, the voltage in discharge process, current instantaneous value, calculate and obtain energy efficiency;

According to energy efficiency, calculate the state of health obtaining a certain series of cells string, wherein, ��_groupFor energy efficiency;

Work as ��_group>80% time, the state of health of a certain series of cells string is excellent; As 50%<��_group< when 80%, the state of health of a certain series of cells string is good; Work as ��_group< when 80%, the state of health of a certain series of cells string is for poor.

Wherein, the formula obtaining energy efficiency utilization is calculated as follows:

${\mathrm{\&eta;}}_{\mathrm{group}}=\frac{{\&Integral;V}_{\mathrm{dis}}\&CenterDot;I_{\mathrm{dis}}\mathrm{dt}}{\&Integral;V_{\mathrm{cha}}\&CenterDot;I_{\mathrm{cha}}\mathrm{dt}}\&CenterDot;100\%;---\left(2\right)$

Wherein, ��_groupFor energy efficiency;

V_dis��I_disUnder demarcating operating mode, in discharge process, voltage, current instantaneous value;

V_cha��I_chaUnder demarcating operating mode, in process of charging, voltage, current instantaneous value;

T is electric discharge start time to electric discharge cut-off condition time used or charging start time to charging cut-off condition time used.

In one embodiment, parameter collection module 2, gathers and the working status parameter that obtains energy-storage units comprises: in discharge process, the voltage change value of a certain series of cells string or battery and curent change value in energy-storage units.

Performance test module 3, generates accumulator system all-round property testing result and comprises:

According in discharge process, in energy-storage units, the voltage change value of a certain series of cells string or battery and curent change value, calculate and obtain a certain series of cells string or internal resistance of cell increment;

According to internal resistance increment, calculate the state of health obtaining a certain series of cells string or battery, wherein, R₀For the internal resistance initial value of a certain series of cells string or battery, �� R is internal resistance increment;

As 0�ܦ� R < R₀Time, the state of health of a certain series of cells string or battery is excellent; Work as R₀�ܦ�R<2R₀Time, the state of health of a certain series of cells string or battery is good; 2R₀�ܦ�R<3R₀Time, the state of health of a certain series of cells string or battery is for poor.

Wherein, the formula obtaining a certain series of cells string or the utilization of internal resistance of cell increment is calculated as follows:

�� R=R_discharge-R₀;(3)

R_discharge=�� U/ �� I; (4)

Wherein, �� R is internal resistance increment;

R₀For the internal resistance initial value of a certain series of cells string or battery;

R_dischargeFor in discharge process, the internal resistance value of a certain series of cells string or battery;

�� U is in discharge process, the voltage change value of a certain series of cells string or battery;

�� I is in discharge process, the curent change value of a certain series of cells string or battery.

In one embodiment, parameter collection module, gathers and the working status parameter that obtains energy-storage units comprises: in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value.

Performance test module 3, generates accumulator system all-round property testing result and comprises:

According to, in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value, calculate and obtain voltage extreme difference;

Under a certain state-of-charge, calculate the voltage consistence result obtaining a certain series of cells string according to voltage extreme difference.

In one embodiment, parameter collection module 2, gathers and the working status parameter that obtains energy-storage units comprises: in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value.

Performance test module 3, generates accumulator system all-round property testing result and comprises:

According to, in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value, calculate and obtain temperature extreme difference;

The voltage consistence result obtaining a certain series of cells string is calculated according to temperature extreme difference.

The present invention by research lithium cell characteristic used for electric vehicle, in conjunction with wind-light storage Demonstration Station accumulator system commissioning test experience, taking operational monitoring data and demarcate operating mode as data source, it is proposed that a kind of state evaluating method being suitable for extensive lithium cell energy-storage units.

Accumulator system is divided into two levels by the accumulator system all-round property testing method of the present invention and device, energy-storage units entirety and series of cells string, wherein energy-storage units whole volume index anomaly unit is carried out series of cells string state estimation, can safeguards system safe operation, and effectively reduce maintenance workload, based on the energy-storage units whole volume index demarcating floor data, energy-storage units state of health can be embodied, also propose the method for multiple assessment series of cells string state of health simultaneously from battery life, aging, consistence angle.

Above-described specific embodiment; the object of the present invention, technical scheme and useful effect have been further described; it is it should be understood that; the foregoing is only specific embodiments of the invention; the protection domain being not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment of making, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (28)

1. an accumulator system all-round property testing method, it is characterised in that, described method comprises:

Step 1, carries out discharge and recharge to the energy-storage units in described accumulator system;

Step 2, gathers and obtains the working status parameter of described energy-storage units;

Step 3, calculates according to the working status parameter of described energy-storage units and generates accumulator system all-round property testing result.

2. accumulator system all-round property testing method according to claim 1, it is characterized in that, in step 2, the working status parameter of described energy-storage units comprises: charging starts and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units.

3. accumulator system all-round property testing method according to claim 2, it is characterised in that, in step 3, the step generating accumulator system all-round property testing result comprises:

Step 311, starts according to described charging and electric discharge terminates the moment, and the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units, calculate the test capacity obtaining energy-storage units;

Step 312, according to the test capacity of the initial capacity of energy-storage units and described energy-storage units, calculates the state of health obtaining energy-storage units, and wherein, E is the test capacity of energy-storage units, E₀For the initial capacity of energy-storage units;

Work as E > 90%E₀Time, it is standard state; Work as 80%E₀< E < 90%E₀Time, it is sub-health state; E < 80%E₀Time, it is unhealthy condition.

4. accumulator system all-round property testing method according to claim 3, it is characterised in that, in step 311, the formula calculating the test capacity utilization obtaining energy-storage units is as follows:

$E={\&Integral;}_{t_0}^{t_1}u\left(t\right)i\left(t\right)\mathrm{dt};---\left(1\right)$

Wherein, E is the test capacity of energy-storage units, and it is for accumulator system is when demarcating, the electric energy that described AC side of converter inputs or outputs when completely filling or completely put;

t₀For energy-storage battery is when demarcating, the start time of charging;

t₁For energy-storage battery is when demarcating, the end moment of charging;

I (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous current value described in journey;

U (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous voltage value described in journey.

5. accumulator system all-round property testing method according to claim 1, it is characterized in that, in step 2, the working status parameter of described energy-storage units comprises: voltage, current instantaneous value in a certain series of cells string process of charging in energy-storage units, the voltage in discharge process, current instantaneous value.

6. accumulator system all-round property testing method according to claim 5, it is characterised in that, in step 3, generate accumulator system all-round property testing result and comprise:

Step 321, according to voltage, current instantaneous value in series of cells string process of charging a certain in described energy-storage units, the voltage in discharge process, current instantaneous value, calculates and obtains energy efficiency;

Step 322, according to described energy efficiency, calculates the state of health obtaining described a certain series of cells string, wherein, and ��_groupFor energy efficiency;

Work as ��_group>80% time, the state of health of a certain series of cells string is excellent; As 50%<��_group< when 80%, the state of health of a certain series of cells string is good; Work as ��_group< when 80%, the state of health of a certain series of cells string is for poor.

7. accumulator system all-round property testing method according to claim 6, it is characterised in that, in step 321, calculate the formula obtaining energy efficiency utilization as follows:

${\mathrm{\&eta;}}_{\mathrm{group}}=\frac{\&Integral;V_{\mathrm{dis}}\&CenterDot;I_{\mathrm{dis}}\mathrm{dt}}{\&Integral;V_{\mathrm{cha}}\&CenterDot;I_{\mathrm{cha}}\mathrm{dt}}\&CenterDot;100\%;---\left(2\right)$

Wherein, ��_groupFor energy efficiency;

V_dis��I_disUnder demarcating operating mode, in discharge process, voltage, current instantaneous value;

V_cha��I_chaUnder demarcating operating mode, in process of charging, voltage, current instantaneous value;

T is electric discharge start time to electric discharge cut-off condition time used or charging start time to charging cut-off condition time used.

8. accumulator system all-round property testing method according to claim 1, it is characterized in that, in step 2, the working status parameter of described energy-storage units comprises: in discharge process, the voltage change value of a certain series of cells string or battery and curent change value in energy-storage units.

9. accumulator system all-round property testing method according to claim 8, it is characterised in that, in step 3, generate accumulator system all-round property testing result and comprise:

Step 331, according in discharge process, in energy-storage units, the voltage change value of a certain series of cells string or battery and curent change value, calculate and obtain a certain series of cells string or internal resistance of cell increment;

Step 332, according to described internal resistance increment, calculates the state of health obtaining described a certain series of cells string or battery, wherein, and R₀For the internal resistance initial value of a certain series of cells string or battery, �� R is internal resistance increment;

As 0�ܦ� R < R₀Time, the state of health of a certain series of cells string or battery is excellent; Work as R₀�ܦ�R<2R₀Time, the state of health of a certain series of cells string or battery is good; 2R₀�ܦ�R<3R₀Time, the state of health of a certain series of cells string or battery is for poor.

10. accumulator system all-round property testing method according to claim 9, it is characterised in that, in step 331, calculate the formula obtaining a certain series of cells string or the utilization of internal resistance of cell increment as follows:

�� R=R_discharge-R₀; (3)

R_discharge=�� U/ �� I; (4)

Wherein, �� R is internal resistance increment;

R₀For the internal resistance initial value of a certain series of cells string or battery;

R_dischargeFor in discharge process, the internal resistance value of a certain series of cells string or battery;

�� U is in discharge process, the voltage change value of a certain series of cells string or battery;

�� I is in discharge process, the curent change value of a certain series of cells string or battery.

11. accumulator system all-round property testing methods according to claim 1, it is characterized in that, in step 2, the working status parameter of described energy-storage units comprises: in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value.

12. accumulator system all-round property testing methods according to claim 11, it is characterised in that, in step 3, generate accumulator system all-round property testing result and comprise:

Step 341, according to, in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value, calculate and obtain voltage extreme difference;

Step 342, under a certain state-of-charge, calculates the voltage consistence result obtaining a certain series of cells string according to voltage extreme difference.

13. accumulator system all-round property testing methods according to claim 1, it is characterized in that, in step 2, the working status parameter of described energy-storage units comprises: in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value.

14. accumulator system all-round property testing methods according to claim 13, it is characterised in that, in step 3, generate accumulator system all-round property testing result and comprise:

Step 351, according to, in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value, calculate and obtain temperature extreme difference;

Step 352, calculates the voltage consistence result obtaining a certain series of cells string according to temperature extreme difference.

15. 1 kinds of accumulator system comprehensive performance test devices, it is characterised in that, described device comprises:

Charge-discharge modules, for carrying out discharge and recharge to the energy-storage units in described accumulator system;

Parameter collection module, for gathering and obtain the working status parameter of described energy-storage units;

Performance test module, calculates for the working status parameter according to described energy-storage units and generates accumulator system all-round property testing result.

16. accumulator system comprehensive performance test devices according to claim 15, it is characterized in that, described parameter collection module, the working status parameter gathered and obtain described energy-storage units comprises: charging starts and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units.

17. accumulator system comprehensive performance test devices according to claim 16, it is characterised in that, described performance test module, generates accumulator system all-round property testing result and comprises:

Starting according to described charging and electric discharge terminates the moment, the instantaneous current value of AC side of converter and instantaneous voltage value in energy-storage units, calculate the test capacity obtaining energy-storage units;

Initial capacity according to energy-storage units and the test capacity of described energy-storage units, calculate the state of health obtaining energy-storage units, and wherein, E is the test capacity of energy-storage units, E₀For the initial capacity of energy-storage units;

Work as E > 90%E₀Time, it is standard state; Work as 80%E₀< E < 90%E₀Time, it is sub-health state; E < 80%E₀Time, it is unhealthy condition.

18. accumulator system comprehensive performance test devices according to claim 17, it is characterised in that, the formula calculating the test capacity utilization obtaining energy-storage units is as follows:

$E={\&Integral;}_{t_0}^{t_1}u\left(t\right)i\left(t\right)\mathrm{dt};---\left(1\right)$

Wherein, E is the test capacity of energy-storage units, and it is for accumulator system is when demarcating, the electric energy that described AC side of converter inputs or outputs when completely filling or completely put;

t₀For energy-storage battery is when demarcating, the start time of charging;

t₁For energy-storage battery is when demarcating, the end moment of charging;

I (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous current value described in journey;

U (t), for energy-storage battery is when demarcating, is completely filling or is completely letting slip AC side of converter instantaneous voltage value described in journey.

19. accumulator system comprehensive performance test devices according to claim 15, it is characterized in that, described parameter collection module, the working status parameter gathered and obtain described energy-storage units comprises: voltage, current instantaneous value in a certain series of cells string process of charging in energy-storage units, the voltage in discharge process, current instantaneous value.

20. accumulator system comprehensive performance test devices according to claim 19, it is characterised in that, described performance test module, generates accumulator system all-round property testing result and comprises:

According to voltage, current instantaneous value in series of cells string process of charging a certain in described energy-storage units, the voltage in discharge process, current instantaneous value, calculate and obtain energy efficiency;

According to described energy efficiency, calculate the state of health obtaining described a certain series of cells string, wherein, ��_groupFor energy efficiency;

Work as ��_group>80% time, the state of health of a certain series of cells string is excellent; As 50%<��_group< when 80%, the state of health of a certain series of cells string is good; Work as ��_group< when 80%, the state of health of a certain series of cells string is for poor.

21. accumulator system comprehensive performance test devices according to claim 20, it is characterised in that, calculate the formula obtaining energy efficiency utilization as follows:

${\mathrm{\&eta;}}_{\mathrm{group}}=\frac{\&Integral;V_{\mathrm{dis}}\&CenterDot;I_{\mathrm{dis}}\mathrm{dt}}{\&Integral;V_{\mathrm{cha}}\&CenterDot;I_{\mathrm{cha}}\mathrm{dt}}\&CenterDot;100\%;---\left(2\right)$

Wherein, ��_groupFor energy efficiency;

V_dis��I_disUnder demarcating operating mode, in discharge process, voltage, current instantaneous value;

V_cha��I_chaUnder demarcating operating mode, in process of charging, voltage, current instantaneous value;

T is electric discharge start time to electric discharge cut-off condition time used or charging start time to charging cut-off condition time used.

22. accumulator system comprehensive performance test devices according to claim 15, it is characterized in that, described parameter collection module, the working status parameter gathered and obtain described energy-storage units comprises: in discharge process, the voltage change value of a certain series of cells string or battery and curent change value in energy-storage units.

23. accumulator system comprehensive performance test devices according to claim 22, it is characterised in that, described performance test module, generates accumulator system all-round property testing result and comprises:

According in discharge process, in energy-storage units, the voltage change value of a certain series of cells string or battery and curent change value, calculate and obtain a certain series of cells string or internal resistance of cell increment;

According to described internal resistance increment, calculate the state of health obtaining described a certain series of cells string or battery, wherein, R₀For the internal resistance initial value of a certain series of cells string or battery, �� R is internal resistance increment;

As 0�ܦ� R < R₀Time, the state of health of a certain series of cells string or battery is excellent; Work as R₀�ܦ�R<2R₀Time, the state of health of a certain series of cells string or battery is good; 2R₀�ܦ�R<3R₀Time, the state of health of a certain series of cells string or battery is for poor.

24. accumulator system comprehensive performance test devices according to claim 23, it is characterised in that, calculate the formula obtaining a certain series of cells string or the utilization of internal resistance of cell increment as follows:

�� R=R_discharge-R₀; (3)

R_discharge=�� U/ �� I; (4)

Wherein, �� R is internal resistance increment;

R₀For the internal resistance initial value of a certain series of cells string or battery;

R_dischargeFor in discharge process, the internal resistance value of a certain series of cells string or battery;

�� U is in discharge process, the voltage change value of a certain series of cells string or battery;

�� I is in discharge process, the curent change value of a certain series of cells string or battery.

25. accumulator system comprehensive performance test devices according to claim 15, it is characterized in that, described parameter collection module, the working status parameter gathered and obtain described energy-storage units comprises: in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value.

26. accumulator system comprehensive performance test devices according to claim 25, it is characterised in that, described performance test module, generates accumulator system all-round property testing result and comprises:

According to, in a certain series of cells string of energy-storage units, monomer battery voltage maximum value and monomer battery voltage minimum value, calculate and obtain voltage extreme difference;

Under a certain state-of-charge, calculate the voltage consistence result obtaining a certain series of cells string according to voltage extreme difference.

27. accumulator system comprehensive performance test devices according to claim 15, it is characterized in that, described parameter collection module, the working status parameter gathered and obtain described energy-storage units comprises: in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value.

28. accumulator system comprehensive performance test devices according to claim 27, it is characterised in that, described performance test module, generates accumulator system all-round property testing result and comprises:

According to, in a certain series of cells string of energy-storage units, cell temperature maximum and cell temperature minimum value, calculate and obtain temperature extreme difference;

The voltage consistence result obtaining a certain series of cells string is calculated according to temperature extreme difference.