[0057] The examples of the present invention will now be explained in detail in the drawings. Although the present invention will be described in connection with the specific embodiments, it will be understood that the present invention will be not intended to limit the invention. Instead, it is desirable to override changes, modifications, and equivalents included in the spirit and scope of the invention. It should be noted that the method steps described herein can be implemented by any functional block or functional arrangement, and any function block or functional arrangement can be implemented as a physical entity or a logic entity, or a combination of both.
[0058] The present invention will be better understood by those skilled in the art, and the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0059] Note: The examples to be described are only a specific example, and not to limit the embodiments of the invention must be the following specific steps, values, conditions, data, order, and the like. Those skilled in the art can use the concept of the present invention to construct more embodiments not mentioned in the present specification by reading this specification.
[0060] The present invention provides a passive equalization control method and system of an electric vehicle battery management system. To solve the balanced opening and closing unreasonably unreasonably unreasonably balanced efficiency in the relevant technique, and unscrupulous opportunities, and the balance management of open loop is caused The problem of accuracy and low accuracy can solve the balanced opening in the related art, turn off the setting rationality, and form a passive equalization strategy for the security and closed loop of the electric vehicle vehicle battery management system.
[0061] Specifically, such as figure 1 As shown, the present invention provides a passive equalization control method of an electric vehicle battery management system, including the following steps:
[0062] S100, get the working mode of the battery system;
[0063] S200, when the battery system is static, or quasi-static, or an external charging mode of operation, obtain the real-time monomer-state value value of the unit cell in the battery system, determine the first target according to the real-time monomer-in-load state value. Balanced monomer;
[0064] S300, controls the first target equalization unit to perform discharge equalization, and detect the change in monomer-loaded state of the first target equalization unit, and determine the correctness of the equalization response and the control equalization of control;
[0065] S400, when detected that the battery system is in the driving discharge mode, obtain the real-time monomer voltage of the battery cell in the battery system, determine the second target equalization unit according to the real-time monomer voltage;
[0066] S500, controls the second target equalization unit to perform discharge equalization, and detect the cell voltage change of the second target equalization unit in real time, and determine the correctness of the equalization response and the control equalization.
[0067] By detection of the operating mode of the battery system, the specific mode of operation of the battery system can be obtained (the battery system is mounted in the vehicle environment, according to the operating conditions of the vehicle, the working mode of the battery system is static or quasi-static, discharged, driving feedback charging As well as external charging (including fast charge, slow charge)) to take different target equalization unit acquisition methods and discharge equalization methods according to different working modes of the battery system. When the battery system is static, or quasi-static, or the external charging mode of charge, the determination and equalization of the target equalization monomer can be performed according to the real-time monomer-containing state value of the battery cell; when the battery system is detected When driving the working mode, the determination and equalization discharge of the target equalization unit can be performed according to the real-time monomer voltage of the battery cell. Due to static, quasi-static and external charging, the monomer-loaded state value is easy to obtain and the estimation accuracy can be accurately locked, and the balanced accuracy is guaranteed; when the traffic is discharged, the current change is large, and it cannot be accurate. Get a single real-time charge status value, using real-time monomer voltage to discuss balanced objectives, add equal opportunities. In this way, considering the operating mode of the battery system in the vehicle environment, it is not easy to leak the equalization opportunity, and the balance accuracy is high.
[0068] Further, in the process of controlling the target equalization unit discharge, the equalization completion of the target equalization monomer can be determined by monitoring the changing state of the monomer or the changing state of the monomer or the change in the monomer voltage. The balanced correctness of the body is detected, and the balanced opening and closing can be accurately performed, and it is not possible to ensure equalization efficiency; and the balanced management can be achieved by detecting equalization completion and its correctness. High accuracy and precision.
[0069] Further, such as figure 2 with Figure 6 As shown in step S200, the "acquisition of the real-time monomer-containing state value of the cell battery in the battery system, determines the first target equalization unit" step according to the real-time monomer charge state value, and specifically includes the steps of:
[0070] S210, acquire the real-time monomer-state value value of the unit cell in the battery system, a normal distribution process for the real-time monomer-load state value of all of the monomer batteries obtained, and obtain a normal distribution of the charge state value SOC. Curve N (μ 1 , Σ 1 2 );
[0071] When the battery system is static, or quasi-static, or external charging mode, the battery management system wakes up the motherboard and slave the board, and the control slave is acquired the real-time monomer-containing state value of the unit cell in the battery system. Sending real-time monomer-load state values to the motherboard, the battery management system controls the real-time monomer-containing state value of all monomer batteries obtained by the motherboard to convert the normal distribution curve N (μ) of the charge state value SOC. 1 , Σ 1 2 ). In this way, the normal distribution curve N (μ) is passed through the charge state value SOC. 1 , Σ 1 2 ), It is easy to determine the target equilibrium monomer, which is also easy to detect the equalization.
[0072] S220, when a real-time monomer-containing state value of a single cell is detected SOC i Located in [μ 1 + (1 + ξ) σ 1 When the + ∞) interval is determined that the monomer battery is the first target equalization unit. At this time, the controller can control the equalization command to the corresponding slave plate.
[0073] When a real-time monomer-loaded state value of a single cell is detected SOC i Located in [μ 1 + (1 + ξ) σ 1 Outside the + ∞), located in [μ 1 Μ 1 + (1-ξ) 1 During the interval, it is determined that the monomer battery is a non-target equalization unit. At this time, the motherboard does not control the equalization instruction to the corresponding slave plate.
[0074] Among them, μ 1 Arithmetic average of the monomer-active state value SOC of all monomer batteries; σ 1 For the variance of the monomer charge state value SOC of all monomer batteries; ξ is equalization variance coefficient, is the battery health status SOH coefficient ξ SOH , Equalization resistance temperature coefficient ξ BRT , Charging estimated time factor ξ BCT Or battery standing time coefficient ξ RST Or battery discharge ratio coefficient ξ BDT Comprehensive weighting product.
[0075] Moreover, the battery health status SOH coefficient calculation formula is ξ SOH = 5 * (Battery actual available capacity / initial capacity) -4; and, equalization resistance temperature coefficient calculation formula is ξ BRT= 1- (t BR -T min,BR ) / (T max,BR -T min,BR ), T BR Perbillation resistance real-time temperature, T min,BR Minimum temperature for equalization resistance, t max,BR The maximum temperature of the equalization resistance is normal, and the calculation formula for charging prevailing time factor is ξ BCT = Expected charging time / full expressive time; battery sedation time coefficient calculation formula is ξ RST = Last standing time / maximum sedation time; battery discharge ratio coefficient calculation formula is ξ BDT = Actual discharge rate / standard discharge rate, energy-type battery standard discharge rate is set to 2C, and the power battery standard discharge ratio is 5c. Battery system equalization variance coefficient in static or quasi-static mode ξ = ξ SOH * ξ BRT * ξ RST Battery system equalization variance coefficient ξ = ξ = ξ = ξ = ξ = ξ SOH * ξ BRT * ξ BCT.
[0076] And, if image 3 with Figure 6 As shown, the above step S300, i.e., the "control first target equalization unit is discharged, and the change of the monomer-loaded state of the first target equalizer is detected in real time, and the correctness of the equalization of the equalization response and the control equilibrium are closed. "Steps, including the following steps:
[0077] S310, controls the first target equalization unit for discharge equalization, and detects the monomer-loaded state change rate ΔSoc of the first target equalization unit in real time. i And non-target equilibrium monomer change rate ΔSoc;
[0078] After receiving the equalization instruction sent by the motherboard, the MOS tube switch of the first target equalization unit is controlled to discharge it, and the passive equalization is achieved. In the process of discharging the first target equalization unit, the discharge equalization state of the first target equalization unit is detected to determine whether the equalization response is correct, whether the equalization is completed, and whether it is necessary to turn off equalization.
[0079] S320, when detected a monomer-loaded state change rate ΔSoc in the first target equalization unit i When the monomer-loaded state change rate ΔSOC is less than the non-target equalization unit, it is determined that the first target equalization unit equalization response is normal, and the first target equalization unit continues to perform discharge equalization. That is, when it is detected that the slave balance response is normal, the first target equalization unit can continue to be equalized.
[0080] When the first target equalization unit change rate ΔSoc is detected i When the monomer-loaded state change rate ΔSo is equal to the non-target equalization unit, it is determined that the first target equalization unit equalization response is not normal, and the first target equalization unit is closed. That is, when the slave plate equalization response is detected, the first target equalization unit cannot be equalized, and the equalization of the first target equalization unit is required to be closed.
[0081] S330, when detected a real-time monomer-loaded state value of the first target equalization unit SOC i Located in [μ 1 Μ 1 + (1-ξ) 1 When the interval is time, it is determined that the first target equalization unit completes the balance and controls the first target equalization unit to close the discharge equalization. In this way, closed loop control of equalization management can be realized.
[0082] Moreover, after the "Control First Target Balance Monomer continues to perform the discharge equalization" step in step S320, the steps of the following steps:
[0083] In the process of controlling the first target equalization unit to continue the discharging equalization, the real-time monomer-containing state value SOC of the first target equalizer is obtained. i;
[0084] When the first target equalization monomer is detected, the real-time monomer-loaded state value SOC is i Located in [μ 1 Μ 1 + (1-ξ) 1 When the interval is time, it is determined that the first target equalization unit completes the balance and controls the first target equalization unit to close the discharge equalization. That is, the discharge equalization of the first target equalization unit can be closed after the first target equalization unit is measured.
[0085] When the first target equalization monomer is detected, the real-time monomer-loaded state value SOC is i In [μ 1 Μ 1 + (1-ξ) 1 At the time of the interval, it is determined that the equalization of the first target equalization monomer is not completed, and the monomer-loaded state change rate ΔSoc of the first target equalization unit is again detected. i And the monomer charge state change rate ΔSoc in non-target equalization monomers. That is, after detecting that the first target equalization unit is unfinished, the monomer-loaded state change rate ΔSoc of the first target equalization unit is re-detected. i.
[0086] When the first target equalization unit change rate ΔSoc is detected i When the monomer-loaded state change rate ΔSOC is less than the non-target equalization unit, it is determined that the first target equalization unit equalization response is normal, and the first target equalization unit continues to perform discharge equalization;
[0087] When the first target equalization unit change rate ΔSoc is detected i When the monomer-loaded state change rate ΔSo is equal to the non-target equalization unit, it is determined that the first target equalization unit equalization response is not normal, and the first target equalization unit is closed.
[0088] The above steps are repeated until the first target equalization monomer is closed after a balance after the balance, or the equalization response is abnormally closed.
[0089] In addition, if Figure 4 with Figure 6 As shown in step S400, the real-time monomer voltage of the battery system in the battery system is determined according to the real-time monomer voltage determination of the second target equalization unit, and specifically includes the steps of:
[0090] S410, obtain the real-time monomer voltage of the cell system in the battery system, a normal distribution process of the real-time monomer voltage of all the unit cells obtained, obtain a normal distribution curve N (μ) of the real-time monomer voltage 2 , Σ 2 2 );
[0091] Similarly, when the battery system is detected in the driving discharge mode, the battery management system wakes up the motherboard and slave the board, and controls the real-time monomer voltage of the unit cell in the battery system, and sends the real-time monomer voltage to The motherboard, the battery management system controls the main board to convert the real-time monomer voltage of all monomer batteries obtained into the normal distribution curve N (μ) 2 , Σ 2 2 ). Thus, the normal distribution curve N of the monomer voltage V (μ) 2 , Σ 2 2 ), It is easy to determine the target equilibrium monomer, which is also easy to detect the equalization.
[0092] S420, when a real-time monomer voltage V is detected a single cell i Located in [μ 2 + (1 + ξ) σ 2 When the + ∞) interval is determined that the unit cell is a second target equalization unit. At this time, the controller can control the equalization command to the corresponding slave plate.
[0093] When a real-time monomer charge state value V is detected in a single cell i Located in [μ 2 + (1 + ξ) σ 2 Outside the [μ2, μ2 + (1-ξ) σ2) interval, it is determined that the monomer battery is a non-target equalization unit. At this time, the motherboard does not control the equalization instruction to the corresponding slave plate.
[0094] Among them, μ 2 Arithmetic average of the monomer voltage of all monomer batteries; σ 2 The variance of the monomer voltage of all monomer batteries; ξ is equalization variance coefficient, is the battery health SOH coefficient ξ SOH , Equalization resistance temperature coefficient ξ BRT , Charging estimated time factor ξ BCT Or battery standing time coefficient ξ RST Or battery discharge ratio coefficient ξ BDT Comprehensive weighting product.
[0095] Similarly, the battery health status SOH coefficient calculation formula is ξ SOH = 5 * (Battery actual available capacity / initial capacity) -4; and, equalization resistance temperature coefficient calculation formula is ξ BRT = 1- (t BR -T min,BR ) / (T max,BR -T min,BR ), T BR Perbillation resistance real-time temperature, T min,BR Minimum temperature for equalization resistance, t max,BR The maximum temperature of the equalization resistance is normal, and the calculation formula for charging prevailing time factor is ξ BCT = Expected charging time / full expressive time; battery sedation time coefficient calculation formula is ξ RST = Last standing time / maximum sedation time; battery discharge ratio coefficient calculation formula is ξ BDT = Actual discharge rate / standard discharge rate, energy-type battery standard discharge rate is set to 2C, and the power battery standard discharge ratio is 5c. Balance variance coefficient ξ = ξ = ξ = ξ = ξ = ξ = ξ = ξ = ξ SOH * ξ BRT * ξ BDT.
[0096] And, if Figure 5 with Figure 6 As shown, the above-described step S500, that is, the "control second target equalization unit is balanced, and the cell voltage change of the second target equalizer is detected in real time, the correctness of determining the equalization response and the control equilibrium closure" step, Specifically, the following steps:
[0097] S510, control the second target equalization unit to perform discharge equalization, and detect the monomer voltage change rate ΔV of the second target equalization unit in real time. i And the monomer voltage change rate ΔV of non-target equalization monomers;
[0098] In the same way, after receiving the equalization instruction sent from the board to the motherboard, the MOS tube switch of the second target equalizer is controlled to discharge the balance, and the passive equilibrium is achieved. In the process of discharging the second target equalization unit, the discharge equalization state of the second target equalization monomer is detected to determine if the equalization response is correct, whether the equalization is completed, and whether it is necessary to turn off equalization.
[0099] S520, when detecting a single voltage change rate ΔV of the second target equalization unit i When the monomer voltage change rate ΔV is greater than the non-target equalization unit, it is determined that the second target equalization unit equalization response is normal, and the second target equalization unit continues to perform discharge equalization. That is, when the slave plate equalization response is detected, the second target equalization unit can be continued.
[0100] When the monomer voltage change rate ΔV of the second target equalization unit is detected iWhen the monomer voltage change rate ΔV is equal to the non-target equalization unit, it is determined that the second target equalization monomer equalization response is not normal, and the second target equalization unit is controlled to close the discharge equalization. That is, when the slave plate equalization response is detected, the second target equalization unit cannot be equalized, and the equalization of the second target equalization unit is required.
[0101] S530, when the real-time monomer voltage V in the second target equalization unit is detected i Bit [μ 2 Μ 2 + (1-ξ) 2 When the interval is interval, it is determined that the second target equalization unit completes the discharge equalization, and controls the closing discharge equalization of the second target equalization unit.
[0102] Moreover, after the "Control Second Target Equile Unit" step in step S520, the discharging equalization step is specifically included in the following steps:
[0103] In the process of controlling the second target equalization unit, the real-time monomer voltage V. i;
[0104] When the real-time monomer voltage V of the first target equalizer is detected i Located in [μ 2 Μ 2 + (1-ξ) 2 When the interval is time, it is determined that the second target equalization unit completes equalization and controls the second target equalization unit to turn off the discharge equalization. That is, the discharge equalization of the second target equalization unit can be closed after the second target equalization unit is detected.
[0105] When the real-time monomer-loaded state value of the second target equalization unit is detected, SOC i In [μ 2 Μ 2 + (1-ξ) 2 At the time of the interval, it is determined that the balance of the second target equalization unit is not completed, and the monomer voltage change rate ΔV of the second target equalizer is again detected. i And the monomer voltage change rate ΔV of non-target equalization monomers. That is, after detecting that the second target equalization unit is unfinished, it is necessary to reconnect the monomer voltage change rate ΔV of the second target equalization unit. i.
[0106] When the monomer voltage change rate ΔV of the second target equalization unit is detected i When the monomer voltage change rate ΔV greater than the non-target equalization unit, it is determined that the second target equalization unit equalization response is normal, and the second target equalization unit continues to perform discharge equalization;
[0107] When the monomer voltage change rate ΔV of the second target equalization unit is detected i When the monomer voltage change rate ΔV is equal to the non-target equalization unit, it is determined that the second target equalization monomer equalization response is not normal, and the second target equalization unit is controlled to close the discharge equalization.
[0108] Repeat the above steps until the second target equalization monomer is closed after a balance, or the equalization response is closed after abnormality.
[0109] Further, the above step S100 is the step of the step of the "acquisition battery system" steps, and specifically includes the following steps:
[0110] S600, when detecting that the battery system is in the driving feedback charging mode, the working mode of the battery system at the previous moment;
[0111] S700, when detecting the battery system at the previous moment, or is quasi-static, or external charging mode of operation, or quasi-static, or quasi-static, or external charging mode according to the battery system;
[0112] S800, when the battery system is detected at the previous moment, in the driving discharge mode of operation, according to the battery system in the driving discharge mode of operation.
[0113] Because the driving feedback charging mode is not long in the vehicle environment, in order not to affect the equalization effect, the equalization mechanism taken along the operating conditions before this mode. That is, when the driving feedback charging mode is static, or when the external charging mode is prejudice, it is balanced according to static, or quasi-static, or the external charging mode of operation is balanced; and in the driving feedback charging mode, in the driving discharge mode When it is balanced in accordance with the driving discharge mode of operation.
[0114] Specifically, the "step S700" is in static or quasi-static, or external charging mode of charge "step, specifically includes the steps of:
[0115] S710, get the real-time monomer-containing state value of the unit cell in the battery system, determine the first target equalization monomer according to the real-time monomer-loaded state value;
[0116] S720, controls the first target equalization unit for discharge equalization, and detects the changing state of the monomer-loaded state of the first target equalization unit in real time, and determines the correctness of the equalization response and the control equalization.
[0117] The above step S700 is basically the same as that step S200 and step S300, and details are not described herein again.
[0118] Further, the "process" in the battery system in the battery system "steps in step S800 steps, including the steps of:
[0119] S810, get the real-time monomer voltage of the battery cell in the battery system, determine the second target equalization unit according to the real-time monomer voltage;
[0120] S820, controls the second target equalization unit for discharge equalization, and detects the cell voltage change of the second target equalization unit in real time, and determines the correctness of the equalization response and the control equalization.
[0121] The above step S800 is substantially the same as the above step S400 and step S500, and details will not be described herein.
[0122] In the second aspect, the present invention provides a passive equalization control system for an electric vehicle battery management system, including:
[0123] Battery working mode acquisition module for acquiring the operating mode of the battery system;
[0124] The first target monomer determines the module, acquires the module communication connection with the battery operating mode, and is used to obtain real-time battery in the battery system when detecting that the battery system is static, or quasi-static, or external charging mode of operation. The monomer-loaded state value determines the first target equalization unit according to the real-time monomer charge state value;
[0125] The first equilibrium control module is connected to the first target monomer, and is used to control the first target equalization unit for discharge equalization, and detect the change in monomer-containing state of the first target equalization unit. The correctness of judging the equalization response and the equalization of control;
[0126] The second target monomer determines the module, acquiring the module communication connection with the battery operating mode, and is used to obtain the real-time monomer voltage of the battery cell in the battery system when it detects that the battery system is in the driving discharge mode. Body voltage determines the second target equilibrium monomer;
[0127] The second equilibrium control module communicates with the second target monomer, configured to control the second target equalization unit for discharge equalization, and detect the cell voltage change of the second target equilibrium monomer in real time, determine the balance The correctness of the response and the equalization of the control balance.
[0128] The passive equalization control system of the electric vehicle battery management system according to the present embodiment corresponds to each other with the passive equalization control method of the above-described electric vehicle battery management system, and the passive equalization control system of the electric vehicle battery management system in this embodiment. The function is described in detail in the corresponding method embodiment, which will not be described herein.
[0129] The invention combined with the battery system in the vehicle environment, the multimode equalization strategy, accurate, reasonably set the equalization control range, improve the equilibrium chance and efficiency, and the real-time determination of the slave panel equilibrium response in real time when the equalization startup is measured. Realize closed-loop management control, improve the security of equalization.
[0130] Based on the same inventive concept, the present application embodiment provides a computer readable storage medium, which stores a computer program, and all method steps or some method steps of the above method are implemented when the computer program is executed by the processor.
[0131] The present invention achieves all or partial flows in the above method, or can be done by a computer program to instruct the hardware, and the computer program can be stored in a computer readable storage medium, which is executed when executed by the processor. The steps of each of the above method embodiments are described above. The computer program includes computer program code, computer program code can be a source code form, object code form, executable file, or some intermediate form. Computer readable media can include: any entity or device capable of carrying computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, READ-ONLY MEMORY), random access Memory (RAM, RANDOMACCESS MEMORY), electrical carrier signal, telecommunications signal, and software distribution media, etc. It should be noted that the contents of the computer readable medium can be appropriately increased, such as in certain jurisdictions, such as legislation and patent practice, in accordance with the requirements of legislation and patent practice within the jurisdiction, according to legislative and patent practice, computer readable media does not include Electrical carrier signal and telecommunications signal.
[0132] Based on the same inventive concept, the present application embodiment provides an electronic device, including a memory and a processor, a computer program that stores a computer program running on a processor, and implements all method steps in the above method when performing a computer program. Some method steps.
[0133] The derivative can be a central processing unit (CPU), as well as other universal processors, Digital Signal Processor, DSP, dedicated integrated circuit (Application Specific Integrated Circuit, ASIC), Programmable gate array (FPGA) or other programmable logic devices, separate gates or transistor logic devices, discrete hardware components, and the like. The general purpose processor can be a microprocessor or the processor can also be any conventional processor, or the like, the processor is the control center of the computer device, using various interfaces and lines to connect the entire computer device.
[0134] The memory can be used to store computer programs and / or models, and processors implement various functions of computer devices by running or performing computer programs and / or models stored in memory, and calling data stored in memory. The memory can primarily include a storage program area and storage data zone, where the storage program area can store the operating system, at least one of the required applications (such as sound playback functions, image playback functions, etc.); storage data area can store according to mobile phones Use the created data (such as audio data, video data, etc.). In addition, memory can include high speed random access memory, as well, non-volatile memory, such as hard disk, memory, plug-in hard disk, smartMedia Card, SMC, secure digital (Secure Digital, SD) card, Flash Card, at least one disk storage device, flash device, or other volatile solid state storage device.
[0135]Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, a system, a server, or a computer program product. Accordingly, the present invention can be in the form of a fully hardware embodiment, a full software embodiment, or a combination of software and hardware aspects. Moreover, the present invention can be in the form of a computer program product implemented in one or more computers including computer available program code (including, but not limited to, disk memory, and optical memory, etc.).
[0136] The present invention is described with reference to a flowchart and / or block diagram of a method, device (system), server, and computer program product according to an embodiment of the present invention. It should be understood that each of the flowcharts and / or blocks in the flowchart and / or block diagram can be implemented by a computer program command, and a combination of flow and / or box in the flowchart and / or block diagram. These computer program instructions can be provided to a general purpose computer, a dedicated computer, an embedded processor, or another programmable data processing device to generate a machine such that instructions executed by the processor of the computer or other programmable data processing device. Implementation in the process Figure one Process or multiple processes and / or boxes Figure one Apparatus specified in multiple boxes or multiple boxes.
[0137] These computer program instructions can also be stored in a computer readable memory capable of booting a computer or other programmable data processing device in a particular manner, making the instructions stored in the computer readable memory generate a manufacturing article of instruction devices, which Device is implemented in the process Figure one Process or multiple processes and / or boxes Figure one The function specified in the box or multiple boxes.
[0138] These computer program instructions can also be loaded on a computer or other programmable data processing device such that a series of steps are performed on a computer or other programmable device to generate a computer implemented process, thereby executing on a computer or other programmable device. The instruction is provided for implementation Figure one Process or multiple processes and / or boxes Figure one The steps of the function specified in multiple boxes or multiple boxes.
[0139] It will be apparent to those skilled in the art, and various modifications and variations are made without departing from the spirit and scope of the invention. Thus, the present invention also intends to include these modifications and variations if these modifications and variations of the invention are within the scope of the claims and equivalents of the present invention.
