WO2021045643A1

WO2021045643A1 - Energy storage system and method for controlling same

Info

Publication number: WO2021045643A1
Application number: PCT/RU2020/000438
Authority: WO
Inventors: Андрей Александрович ШВЕД; Даниил Андреевич ШВЕД
Original assignee: Общество с ограниченной ответственностью "Смартер"
Priority date: 2019-09-02
Filing date: 2020-08-18
Publication date: 2021-03-11
Also published as: RU2721227C1

Abstract

The invention relates to the field of electrical engineering, in particular to electric propulsion systems for vehicles. The aims of the invention are to reduce the weight and cost of an energy storage system and to increase the service life thereof. The energy storage system consists of a power section (1), means (2) for assessing states of the power section, and control means (3). The power section comprises power terminals (5, 6), a storage battery (7), a capacitor bank (8) and a converter (9) with a converter control input (10). The control means (3) comprise an information interface (4), an input data set (11), an optimal control program (12) for generating a setpoint for the converter control input (10), and a program (13) for generating a prediction of the output electrical power of the system on the basis of data from navigation and traffic assessment means (14). The optimal control program (12) takes into account not only the current requirements for the output electric power of the system, but also the requirements that may arise in the near future, which improves the operating conditions of the storage battery and capacitor bank.

Description

ENERGY STORAGE SYSTEM AND METHOD OF ITS CONTROL

The invention relates to the field of electrical engineering, in particular - to electrical power plants of transport vehicles, mainly unmanned vehicles.

Electrically powered vehicles such as hybrid vehicles with combustion engines or fuel cells, electric vehicles and electric buses are increasingly being used. They include rechargeable batteries, the efficiency of which largely determines the cost and technical characteristics of transport vehicles.

Known methods for managing energy consumption in hybrid vehicles (WO 2013/131735 AZ; U.S. Pat. N ° 8,606,513 B2; U.S. Pat. Ko 10,131,341 B2) based on taking into account the peculiarities of the movement of cars in various road conditions. These methods can improve the efficiency of using batteries, but not enough. This is due to the fact that storage batteries have a relatively low specific power, and it is necessary to increase their mass in order to provide a sufficiently intensive acceleration or regenerative braking of a transport vehicle.

Known energy storage systems for electrical power plants of transport vehicles, which include a combination of two energy storage devices: the first is a storage battery (secondary chemical current source) with high specific energy, the second is a capacitor bank (a battery of capacitors with a double electric layer, also referred to as supercapacitors), which has a high power density. In this case, various means and methods are used. energy distribution between storage and capacitor banks (US Pat. W 5,373,195; US Pat. W 7,258,183 B2; US Pat. W 7,780,562 B2; US Pat. J ° 7,791,216 B2; US Pat. J "7,936,083 B2; US Pat. W 8,434,578 B2 ; US Pat. W 8,860,359 B2; US Pat. W 9,162,669 B2; US Pat. W 9,895,983 B2; US Pat. W 10,050,439 B2; US Pat. W 10,293,702 B2).

In the above technical solutions, the output / reception of energy by the capacitor bank occurs as a reaction to the current demand arising during the acceleration or regenerative braking of the transport vehicle, and the amount of energy stored in the capacitor bank deviates from the preset initial level E ₀ to a smaller or larger side, and then returns to him; the operating energy capacity of the capacitor bank is

where E _max , E _min - respectively the maximum and minimum permissible levels of energy stored by the capacitor bank, E _ret = E ₀ - E _min - the potential demand for the energy supplied by the capacitor bank, E _rec = E _max - E ₀ - the potential demand for the received capacitor bank energy. The general disadvantage of these solutions is the ineffective use of the capacitor bank, which must have a significant (up to two times at E _ret = E _ges ) excess of operational energy capacity in relation to the potential demand for the energy it receives or receives.

From among the above technical solutions, the method and system of energy storage of a transport machine (US Pat. N ° 7,791,216 B2) were selected as a prototype of the claimed invention. This system is a part of the electric power plant of a transport machine and consists of a power unit and a controller containing means for assessing the states of the power unit, means control and information interface, and the power section contains the power terminals of the system (a bus for connecting to the electric drive of the drive wheels), a storage battery, a capacitor bank and a converter with a control input of the converter, which are connected so that p ₌ p + p _ p A out ^A ab ¹ cb ^А с 'where P _out is the output electric power of the energy storage system, measured at its power terminals, P _ab is the output electric power of the storage battery, P _cb is the output electric power of the capacitor bank, P _c is the power losses in the converter, and the ratio powers P _ab , P _cb and P _c depends on the setting at the control input of the converter.

The control in the prototype is carried out so that the ratio of the powers P _ab , P _cb and P _c is determined by the amount of energy E stored in the capacitor bank, in particular, when P _out > 0:

- if a

- if E ₂ <E <E _b then P _ab > 0, P _cb > 0, P _c >0;

- if E <E ₂ , then P _ab > 0, P _cb = 0, P _c > 0, where E ₁ E _{2 are} threshold levels.

Thus, in the prototype, the process of giving / receiving energy includes the stages at which the entire output electrical power of the energy storage system is provided exclusively by capacitor or rechargeable batteries - energy losses on the internal resistances of the batteries are proportional to the square of their output currents and can be minimized due to uniform distribution of these currents, which is not performed in this case.

The objectives of the claimed invention are to reduce the weight and cost of the energy storage system, increase its resource. Technical results that allow solving the task: reducing the energy consumption of the capacitor bank, improving the operating modes of the converter, storage and capacitor banks by minimizing energy losses in them.

The technical results are achieved by the fact that in the energy storage system (hereinafter referred to as the system), consisting of a power section, means for assessing the states of the power section and controls equipped with an information interface, and the power section contains the power terminals of the system, a storage battery, a capacitor bank and a converter with control input of the converter, which are connected so that p

¹ out

where P _out is the output electric power of the system, measured at its power terminals, P _ab is the output electric power of the storage battery, P _cb is the output electric power of the capacitor bank, P _c is the power losses in the converter, and the ratio of the powers P _ab , P _cb and P _s depends on the setpoint Ref at the control input of the converter, according to the claimed invention, an array of input data and an optimal control program are introduced into the control means, and:

- the array of input data has the ability to fill through the information interface and contains a forecast P _f power P _out ;

- the optimal control program is connected with an array of input data, means for assessing the states of the power unit and the control input of the converter and serves to form the setpoint Ref, which minimizes the value of the function W from the energy losses expected during the forecast lead time P _f .

The system can be implemented in such a way that the formation of the Ref setpoint consists in choosing one of the many predictive options for its changes based on dynamic programming methods, and the selection criterion is the minimum value of the function

W = W _ab + k _j -W _cb + k ₂ -W _c , where k _l5 k ₂ are weight factors, W _ab is the amount of energy loss on the internal resistance of the battery, W _cb is the amount of energy loss on the internal resistance of the capacitor bank, W _c - the amount of energy losses in the converter.

In the converter circuit, half-bridges can be used, each of which has a half-bridge control input, a first switch, a second switch, a positive terminal, a negative terminal and a switched terminal, the positive terminal is connected to the switched terminal through the first switch, the negative terminal is connected to the switched terminal through the second switch. the switched output has the ability to connect to the positive or negative output by a signal at the control input of the half-bridge.

The first version of the converter contains two half-bridges, a choke with a choke current sensor and a regulator, moreover:

- the positive and negative terminals of the first half-bridge are connected in parallel to the battery, the negative terminal of the first half-bridge is connected to the negative terminal of the second half-bridge, the switchable terminal of the first half-bridge is connected through a choke to the switchable terminal of the second half-bridge, the positive and negative terminals of which are connected in parallel to the capacitor bank;

- the regulator has three inputs and two outputs, a general feedback signal is applied to the first input of the regulator from the means for assessing the states of the power section of the open circuit of the capacitor bank, the second input of the regulator is the control input of the converter, a local feedback signal from the sensor is applied to the third input of the regulator choke current, the outputs of the regulator are connected to the control inputs of the half-bridges. In the first version of the converter, the power terminals of the system can be the plus and minus terminals of either of the two half-bridges.

The second version of the converter contains a half-bridge, a choke with a choke current sensor and a regulator, moreover:

- the plus and minus terminals of the half-bridge are power terminals of the energy storage system, the negative terminal of the half-bridge is connected to the negative terminal of the battery, the switchable terminal of the half-bridge is connected through the choke to the positive terminal of the battery and the negative terminal of the capacitor bank, the positive terminal of which is connected to the positive terminal of the half-bridge;

- the regulator has three inputs and an output, to the first input of the regulator from the means for evaluating the states of the power unit, a general feedback signal is applied to the voltage of the open circuit of the capacitor bank, the second input of the regulator is the control input of the converter, to the third input of the regulator a local feedback signal from the current sensor is applied choke, the output of the regulator is connected to the control input of the half-bridge.

The regulator in both converter versions is designed so that the general feedback signal at the first regulator input tends to the Ref setpoint at the second regulator input.

The system can be placed on an electric vehicle with navigation and traffic assessment tools, and a program for the cyclic formation of a forecast P _f , built on the basis of data analysis of navigation aids and an assessment of the traffic situation, is included in the control facilities.

The specified electric vehicle may contain a heat-insulating compartment, while:

- the battery has a capacity that provides no more than 100 kilometers of run of an electric vehicle without recharging, and is placed in a heat-insulating compartment so that it is possible prompt replacement;

- on the territory of the intended operation of the electric vehicle, a network of stations is located for the rapid replacement of batteries and their charging, combined with heating or cooling of batteries to optimal operating temperatures.

When controlling a system containing a storage battery, a capacitor bank and a converter with a control input of the converter, which are connected in such a way that p r = P 4 P p out ab ^r cb ^g c> where P _{out is the} output electrical power of the system, P _ab is the output electrical the power of the storage battery, P _cb is the output electric power of the capacitor bank, P _c is the power losses in the converter, and the ratio of the powers P _ab , P _cb and P _c depends on the setting Ref at the control input of the converter, according to the claimed method, a finite set U of voltage values is set and then cyclically perform the following actions:

- form a forecast P _{f of} power P _out and divide the forecast lead period P _f into a plurality of time intervals;

- at each time interval, a set of predictive options for changing the voltage of the open circuit of the capacitor bank is formed so that at the boundaries of the time interval the value of this voltage belongs to a given finite set U, and for each option, the loss w is calculated, corresponding to the execution of the prediction P _f , according to the formula

where k _b k ₂ are weight factors, w _ab is the amount of energy loss on the internal resistance of the battery, w _{cb is the} amount of losses energy on the internal resistance of the capacitor bank, w _c - the amount of energy loss in the converter;

- from the set of generated predictive options, a sequence is selected that forms a continuous function uf (t) with a minimum amount of losses w, then a setting Ref is supplied to the control input of the converter such that the value of the open circuit voltage of the capacitor bank tends to ut (t).

The inventive control method can be applied so that the cyclical execution of these actions is carried out with a repetition period that is many times less than the prediction period P _f .

The inventive control method can be applied to an electric vehicle with navigation aids, the data of which is used to draw up a route, and means for assessing the traffic situation, the data of which is used to predict the schedule of movement of an electric vehicle along a route, and the forecast P _f is generated according to the formula

P _f = (m-vdv / dt + mg-dh / dt + P _w ) / h, where m is the mass of the electric vehicle, v, h are the predicted speed and altitude of the electric vehicle, g is the acceleration due to gravity, P _w is the predicted power losses due to rolling friction and aerodynamic resistance of an electric vehicle, h is the efficiency of the electric drive of the driving wheels of an electric vehicle, and the prediction period P _{f is} set so that it exceeds the value

( ^E max - ^E ttUR av> where E _max , E _{min are the} maximum and minimum possible energy reserves of the capacitor bank, P _av is the average power P _out when an electric vehicle moves along a highway with a high-quality surface.

The essential features of the proposed solution affect the achievement technical result as follows:

The storage battery has a high specific energy, and the capacitor bank has a high specific power. The system with high specific indicators of energy and power consists of a power section, means for assessing the states of the power section and control means, and the power section contains the power terminals of the system, a storage battery, a capacitor bank and a converter with a control input of the converter, which are connected in a certain way. These features are known from the state of the art and offer the potential for optimizing the distribution of the electrical power output of the system between the storage battery and the capacitor bank.

A new feature: "the array of input data ... contains the forecast P _f power P _out " allows you to plan the output or reception of energy by the capacitor bank not only as a response to the current demand arising from surges in the output electrical power of the system, but also to prepare the capacitor bank for such surges , namely, to discharge it before receiving energy, or to charge it before releasing energy. In this case, the capacitor bank will be used as efficiently as possible, since its operational energy capacity will not be excessive in relation to the potential demand for the energy supplied or received.

The implementation of the above possibility is provided by a new feature: "the optimal control program ... for the formation of the setpoint Ref, which minimizes the value of the function W from the energy losses expected during the forecast lead time P _f ".

The formation algorithm is disclosed in the attribute: "the formation of the Ref setting consists in choosing one of the many predictive options for its changes based on dynamic programming techniques. " The latter are widely known (Bellman R. // Dynamic programming. - Moscow: Foreign Literature Publishing House, I960; Cormen T., Leiserson C., Rivest R, Stein K. // Algorithms: construction and analysis. - Moscow: Williams , 2005.).

Sign: "the minimum value of the function

W = W _ab + k, -W _cb + k ₂ -W _c , where k ₁ k ₂ are weight factors ,, W _{ab is the} amount of energy loss on the internal resistance of the battery, W _cb is the amount of energy loss on the internal resistance of the capacitor bank , W _c - the amount of energy losses in the converter ”reveals one of the possible selection criteria. For a person skilled in the art it should be clear that the weighting factors are set depending on the specific parameters of the system, in particular, these factors can be set to zero if the operating temperatures of the capacitor bank and converter do not exceed a safe level. In this case, the operating mode of the battery will be maximally improved by minimizing energy losses on its internal resistance. Since the storage battery is the most heavy, expensive and short-lived element of the system, the set objectives of reducing the weight, cost, and increasing the resource of the system will be solved.

Features revealing options for constructing a converter are known from the state of the art and are illustrative.

Signs: "The system ... is located on an electric vehicle that has navigation and traffic conditions assessment tools, and a program for cyclic forecasting P _f , built on the basis of data analysis of navigation aids and traffic situation assessment, has been introduced into the control tools" are obvious for a specialist in this field techniques and are explanatory.

The introduction of the feature: "the battery ... is housed in a heat-insulating compartment" was made possible by minimizing energy losses on the internal resistance of the battery. With minimal energy losses, the thermal capacity of the battery is sufficient to prevent overheating, which eliminates the need for forced cooling. By placing the battery in a heat-insulating compartment, the impact of harmful factors such as low or high ambient temperatures is reduced.

The introduction of the feature: "the storage battery has a capacity that provides no more than 100 kilometers of run of an electric vehicle without recharging" was made possible by reducing the power requirements of the storage battery (due to the presence of a capacitor battery). The low capacity of the rechargeable battery makes it light and small, that is, to implement the sign: "the rechargeable battery ... is placed ... so that it can be quickly replaced."

The sign: "on the territory of the intended operation of the electric vehicle, a network of stations is located for the rapid replacement of batteries and their charging ..." is obvious to a person skilled in the art and is explanatory.

A new feature: "... charging combined with heating or cooling batteries to optimal operating temperatures" allows (in conjunction with placing the battery in a heat-insulating compartment) to improve the operating mode of the battery.

A new set of features of the control method: “set a finite set U of voltage values ... split the lead period predicting P _f for multiple time intervals;

- at each time interval, a set of predictive options for changing the voltage of the open circuit of the capacitor bank is formed so that at the boundaries of the time interval the value of this voltage belongs to a given finite set U, and for each option, the loss w ... is calculated;

- from the set of generated predictive options, a sequence is selected that forms a continuous function u _f (t) with a minimum amount of losses w "allows you to reduce the problem of finding optimal control to the well-known problem of finding the shortest path in a directed acyclic graph (see p. 197 in the book. Christofides N. // Graph Theory. Algorithmic Approach. - M .: Mir, 1978.).

Sign: "the cyclical execution of these actions is carried out with a repetition period that is many times smaller than the prediction period P _f " allows you to make timely adjustments to the power distribution process when the forecast P _f changes.

The method for generating a forecast P _{f is} disclosed in the features characterizing the claimed solution in relation to an electric vehicle, mainly an unmanned vehicle - in this case, the method is the simplest and is given as an illustrative example. The scope of the proposed solution is not limited to the given example. In particular, the formation of forecasts of the electric power output of systems intended for hybrid transport vehicles, industrial drives, autonomous electric power devices, etc. refers to separate tasks that are not the subject of this application. Achievement of the technical result in the claimed solution is ensured regardless of the method for generating the forecast of the system's electrical output power.

Thus, the claimed technical solution contains features, unknown from the prior art and influencing the achievement of the technical result, that is, it meets the criteria of "novelty" and "inventive step".

The claimed technical solution is illustrated by drawings.

FIG. 1 contains a block diagram of the system.

FIG. 2, 3, 4 contain options for circuits of the power part of the system.

FIG. 5 illustrates the optimal control process.

FIG. 6 illustrates a path in a directed acyclic graph. FIG. 7 illustrates an example of the implementation of the control method.

FIG. 8 illustrates a variant of an unmanned electric vehicle.

The block diagram (Fig. 1) shows:

- power unit 1;

- means 2 for assessing the states of the power unit;

- control means 3 with information interface 4;

- plus 5 and minus 6 power terminals of the system;

- storage battery 7;

- capacitor bank 8;

- converter 9 with converter control input 10;

- array of 11 input data;

- program 12 optimal control;

- the program 13 of the cyclical formation of the forecast of the output electrical power of the system;

- means 14 for navigation and traffic assessment.

The storage battery 7 is connected to the capacitor bank 8 through the converter 9, these elements, together with the terminals 5, 6, form a power section 1, which is controlled by the control input 10 of the converter; the power section 1 is connected with the means 2 for assessing the states of the power section.

Means 2 for assessing the states of the power section contain, at least: - means for evaluating the voltage of the open circuit and the internal resistance of the storage battery 7;

- means for evaluating the voltage of the open circuit and the internal resistance of the capacitor bank 8.

To assess the states, well-known algorithms can be used, such as the Kalman filter or the Luenberger observer (Andreev Yu. N. // Control of finite-dimensional linear objects - M .: Main edition of physical and mathematical literature of the publishing house "Nauka", 1976.).

The control means 3 include an array of 11 input data, an optimal control program 12, a program 13 for the cyclical formation of a forecast of the output electric power of the system; the program 13 has the ability to receive data from the means 14 of navigation and assess the traffic situation, as well as write data to the array 11 through the information interface 4; the program 12 has the ability to receive data from the array 11 and from the means 2 for assessing the states of the power unit, as well as transmitting data to the control input 10 of the converter.

The diagrams (Fig. 2, 3) show the power section 1 with the first version of the converter 9, which includes:

- the first and second half-bridges 20, 21, each of which has a control input, a positive terminal, a negative terminal and a switchable terminal;

- a choke 22 with a choke current sensor 23;

- regulator 24 with three inputs 25, 10, 26 and outputs 27, 28.

To the first input 25 of the regulator a signal of the general feedback on voltage and an open circuit of the capacitor bank is applied, the second input of the regulator is the master input 10 of the converter, to the third input 26 of the regulator a signal of local feedback from the sensor 23 of the choke current is applied, the outputs 27, 28 of the regulator are connected to half-bridge control inputs; positive and negative conclusions of the first half-bridge 20 connected in parallel to the battery 7, the negative terminal of the first half-bridge 20 is connected to the negative terminal of the second half-bridge 21, the switchable terminal of the first half-bridge 20 is connected through the choke 22 to the switched terminal of the second half-bridge 21, the positive and negative terminals of which are connected in parallel to the capacitor bank 8.

In the power section 1, containing the first version of the converter, the power terminals 5, 6 of the system can be: positive and negative terminals of the second half-bridge 21 (as shown in Fig. 2), or positive and negative terminals of the first half-bridge 20 (as shown in Fig. 3 ).

The diagram (Fig. 4) shows the power section 1 with the second version of the converter 9, which includes:

- half-bridge 30, which has a control input, a positive terminal, a negative terminal and a switchable terminal;

- a choke 31 with a choke current sensor 32;

- regulator 33 with three inputs 34, 10, 35 and output 36.

The first input 34 of the regulator is fed with a common feedback signal for the voltage and the open circuit of the capacitor bank, the second input of the regulator is the control input 10 of the converter, the third input 36 of the regulator is fed with a local feedback signal from the sensor 32 of the choke current, the output 36 of the regulator is connected to the control input half-bridge 30; the positive and negative terminals of the half-bridge 30 are power terminals 5, 6 of the system, the negative terminal of the half-bridge 30 is connected to the negative terminal of the battery 7, the switchable terminal of the half-bridge 30 is connected through the throttle 31 to the positive terminal of the battery 7 and the negative terminal of the capacitor bank 8, the positive terminal of which connected to the positive terminal of the half-bridge 30.

The choice of power unit option 1 is determined by the specific parameters of the system: - in cases where the output power of the capacitor bank 8 is significantly (more than 3 times) higher than the power of the battery 7 (for example, in a hybrid car), the circuit shown in FIG. 2;

- in cases where the output power of the capacitor bank 8 is approximately equal to the power of the battery 7 (for example, in an electric bus), the circuit shown in FIG. 3;

- in other cases (for example, in an electric vehicle), the circuit shown in FIG. four.

In all these variants, the principle of operation of the converter 9 is the same, and is illustrated by the example of the diagram of FIG. four:

When periodic rectangular pulses are fed from the output 36 of the regulator to the control input of the half-bridge 30, the switchable output of the half-bridge 30 is periodically connected to its positive or negative terminals. In this case, the average voltage at the switched output of the half-bridge 30 depends on the duty cycle of the pulses at the output 36 of the regulator. The change in the current of the choke 31 is determined by the voltage difference at its terminals and, therefore, also depends on the duty cycle of the pulses at the output 36 of the regulator. The choke current affects the distribution of the output electrical power of the system between the storage battery 7 and the capacitor battery 8. The voltage and open circuit of the capacitor bank 8 varies depending on its output electrical power. The regulator 33 is designed so that the voltage at input 34 also tends to the Ref setpoint at input 10. The principle of operation of the regulator is known and does not require additional explanations.

An example of the implementation of the proposed control method is illustrated in Fig. 5, 6 and described below.

Program 12 receives from means 2 data on the state of the power unit (open circuit voltage and internal resistance accumulator 7 and capacitor 8 batteries), and from array 11 forecast Pf of the output electric power of the system. Note that the internal resistance of the capacitor bank 8, as well as the open-circuit voltage and the internal resistance of the battery 7 change rather slowly, and during the prediction period Pf they can be considered constant. Program 12 solves the problem of finding the optimal control using the following algorithm:

1) Within the operating range (u _m in, Umax), a finite set U of values of the open circuit voltage of the capacitor bank is set.

2) Divide the forecast lead period P _f into time intervals (ί, t _j ), where i is the number of the interval from 1 to N.

3) At each time interval, a set of predictive options Ref _{ijk of} the setpoint change Ref. In accordance with the principle of operation of the converter, the open-circuit voltage of the capacitor bank should tend to the setting Ref - the formation of predictive options is carried out so that each moment of time f corresponds to the values Uy of the open-circuit voltage of the capacitor bank from a given finite set U.

4) For each forecast option Refi _{jk, the} loss w _{ijk is calculated} (for example, the amount of energy loss on the internal resistance of the battery) corresponding to the implementation of the forecast Pf, using data on the state of the power unit and its mathematical model.

5) Present forecast options in the form of a directed acyclic graph (Fig. 6) with a set of vertices (i, j) and a set of flyr (i, j, k). The arcs (1D, k) are directed to the vertex (i, j) from the vertices (i - 1, j '), the index k takes values from 1 to K, where K is the number of arcs directed to the vertex (i, j). The values ii ^ correspond to the vertices, and Refi _jk and w _{ijk to the arcs} . 6) Sequentially increasing i from 1 to N, assign to the vertices (i, j) marks W (i, j), equal to the minimum amount of losses on the way to them:

W (i, j) = min [W (il, j ') + w _ijk ], (1) where (i, j, k) runs through the set of all arcs directed to the vertex (i, j), W (i- 1, j ') are the marks previously assigned to the vertices from which the arcs (1, j, k) are directed, W (0, 0) = 0 is the mark assigned to the beginning of the graph. One (N, M) with the smallest mark is selected from all vertices (N, j). Of all arcs (N, M, k), choose one (N, M, L) that satisfies formula (1). The arc (N, M, L) lies on the path with the least amount of losses.

7) Sequentially moving from the vertex (N, M) to the vertex (0, 0) along the arcs satisfying formula (1), a path with the least amount of losses is obtained (marked in Fig. 6 by arrows). This path corresponds to the sequence of settings Ref _jk , which provides optimal control, and is transmitted by the program 12 to the control input 10 of the converter.

Due to possible unpredictable changes in traffic conditions, the cycle shown in FIG. 5, should be carried out as often as possible - in order to avoid significant discrepancies between the output electrical power Pout and its forecast P _f .

FIG. 7 shows an example of the system operation when an electric vehicle is moving. The route is divided into sections by points 40, 41, 42, 43, 44, 45. The forecast is updated at each point. Forecast lead periods intersect (each of them corresponds to two sections of the route). The graph of energy (E = Cchg / 2) stored in the capacitor bank (solid thickened line) is formed by many intersecting fragments corresponding to different sections of the route:

- fragment 50 corresponds to the section up to point 41; - fragment 51 corresponds to section 40 + 42;

- fragment 52 corresponds to section 41 + 43;

- fragment 53 corresponds to section 42 + 44;

- fragment 54 corresponds to section 43 + 45.

The Ref setpoint at the control input of the converter is formed based on the most recent forecast, while the E graph is updated, which may differ from the previous one (dashed line):

- the forecast generated in paragraph 40 takes into account the descent of the electric vehicle in the section 41 + 42, therefore, in the section 40 + 41, the updated fragment 51 is below the previous fragment 50, which ensures the preparation of the capacitor bank to receive energy on the descent;

- section 42 43 does not contain significant changes in the relief, and also does not imply acceleration / deceleration of an electric vehicle, therefore, in section 41 + 42, the updated fragment 52 differs little from the previous fragment 51;

- the forecast generated in paragraph 42 takes into account the rise of the electric vehicle in the section 43 + 44, therefore, in the section 42 + 43, the updated fragment 53 is higher than the previous fragment 52, which ensures the preparation of the capacitor bank for energy release on the rise;

- the forecast generated in paragraph 43 takes into account the braking of the electric vehicle before the intersection 45, therefore, in section 43 + 44, the updated fragment 54 is higher than the previous fragment 53.

Thus, the optimal control program takes into account not only the current requirements for the output electrical power of the system, but also those needs that may arise in the near future.

The variant of the unmanned electric vehicle 60 (FIG. 8) has drive wheels 61 mechanically connected to the electric machines 62. The electric machines 62 are connected to AC / DC converters 63, which are powered by an energy storage system with the power section variant shown in FIG. 4. Electric vehicle 60 contains a heat-insulating compartment 64 in which a storage battery 7 is located.

This option allows you to solve two main problems inherent in electric vehicles - long charging times and unreliable operation at negative ambient temperatures. Due to a significant reduction in energy losses on the internal resistance of the storage battery, the proposed option allows, in comparison with traditional ones, to reduce the weight and dimensions of the storage battery at least threefold. At the same time, the mileage of an electric vehicle without recharging decreases, but its dynamics does not deteriorate. After discharge, a small rechargeable battery can be easily and quickly replaced with a fresh one.

The network of stations 65 is used for prompt robotic replacement of discharged batteries with fresh ones. A fresh (charged) storage battery has an electrolyte temperature close to optimal. During a short run (no more than 100 km), the temperature of the electrolyte of the battery 5, placed in the heat-insulating compartment 61, does not have time to change significantly, which increases the reliability of the battery in winter, and in summer eliminates the need for its forced cooling. Thus, the proposed version of the electric vehicle 60 provides storage of not only electrical, but also thermal energy.

The unmanned electric car 60 is preferable to use as a city taxi, the route of which is compiled automatically and provides for visits to robotic points to quickly replace batteries.

Claims

CLAIM

1. An energy storage system, consisting of a power section, means for assessing the states of the power section and controls equipped with an information interface, and the power section contains the power terminals of the energy storage system, a storage battery, a capacitor bank and a converter with a control input of the converter, which are connected in such a way, what

P ^g out = P ^r ab + ^g P cb - P ^g c 'where P _out is the output electric power of the energy storage system, measured at its power terminals, P _{ab is the} output electric power of the storage battery, P _cb is the output electric power of the capacitor bank , _with P _- power losses in the converter and the capacity ratio P _ab, P _ch and R _c depends on Ref setpoint at the control input of the converter, characterized in that the composition controls administered array input data and programmable sh'ma optimal control, wherein:

- the array of input data has the ability to fill through the information interface and contains the forecast P _{f of the} value P _out ;

- the optimal control program is connected with an array of input data, means for assessing the states of the power unit and the control input of the converter and serves to form the setpoint Ref minimizing the value of the function W from the energy losses expected during the forecast lead period P _f .

2. The system according to claim 1, characterized in that the formation of the Ref setpoint consists in choosing one of the many advanced options for changing it, based on dynamic programming methods, and

W = W _ab + k _j -W _cb + k ₂ -W _c , where k _j , k ₂ - weight coefficients, W _ab is the amount of energy losses on the internal resistance of the storage battery, W _cb is the amount of energy losses on the internal resistance of the capacitor bank, W _c is the amount of energy losses in the converter.

3. The system according to claim 1, characterized in that the converter contains two half-bridges, a choke with a choke current sensor and a regulator, and:

- each half-bridge has a half-bridge control input, a first key, a second key, a positive terminal, a negative terminal and a switched terminal, the positive terminal is connected to the switched terminal through the first switch, the negative terminal is connected to the switched terminal through the second switch, the switched terminal has the ability to connect to the positive or to the minus terminal according to the signal at the control input of the half-bridge; - positive and negative terminals of the first half / 'remain connected in parallel to the battery, the negative terminal of the first half-bridge is connected to a minus terminal of a ^m orogo half-bridge, half-bridge switching terminal of the first through-Yucel et al is connected to the second terminal of the switchable half-bridge, plus and minus ?, th the leads of which are connected in parallel to the condensate bank;

- the plus and minus terminals of the first or second bridges are the power terminals of the energy storage system;

- the regulator has three inputs and two outputs, the first input of the regulator from the means for assessing the states of the power section is fed with a general feedback on the voltage of the open circuit to the capacitor u of the battery, the second input of the regulator is the control input of the converter, a signal is applied to the third input of the regulator local feedback from the choke current sensor, the regulator outputs are connected to the control inputs of the olumosts.

4. The system according to claim 1, characterized in that the converter has a half-bridge, a choke with a choke current sensor and a regulator, and: - the half-bridge has a control input, a first key, a second key, a positive terminal, a negative terminal and a switched terminal, the positive terminal is connected to the switched terminal through the first switch, the negative terminal is connected to the switched terminal through the second switch, the switched terminal can be connected to the positive or minus terminal on the signal at the control input of the half-bridge;

5. The system according to claim 1, characterized in that it is located on an electric vehicle having navigation and traffic assessment tools, and the control facilities include a program for cyclic forecasting P _f based on the analysis of navigation data and traffic assessment.

6. The system according to claim 5, characterized in that the electric vehicle contains an insulating compartment, and:

- the storage battery has a capacity that provides no more than 100 kilometers of run of an electric vehicle without recharging, and is placed in a heat-insulating compartment so that it can be quickly replaced; - on the territory of the intended operation of the electric vehicle, a network of stations is located for the rapid replacement of batteries and their charging, combined with heating or cooling of batteries to optimal operating temperatures.

7. A method for controlling an energy storage system containing a storage battery, a capacitor bank and a converter with a control input of the converter, which are connected so that

P ₌ P J- P _ p A out ^A ab cb ^x c 'where P _out is the output electric power of the energy storage system, P _{ab is the} output electric power of the storage battery, P _cb is the output electric power of the capacitor bank, P _c is the power loss in the converter, and the ratio of the powers P _ab , P _cb and P _c depends on the setting Ref at the control input of the converter, characterized in that they set a finite set U of voltage values and then cyclically perform the following actions:

where k _b k ₂ - weight coefficients, w _ab - the amount of energy loss on the internal resistance of the battery, w _cb - the amount of energy loss on the internal resistance of the capacitor bank, w _c is the amount of energy losses in the converter;

- from the set of generated predictive options, a sequence is selected that forms a continuous function Uf (t) with a minimum amount of losses w, then a setting Ref is supplied to the control input of the converter such that the value of the open circuit voltage of the capacitor bank tends to u _t {t).

8. The method according to claim 7, characterized in that the cyclical execution of these actions is carried out with a repetition period that is many times less than the prediction period P _f .

9. The method according to claim 7, characterized in that it is used on an electric vehicle with navigation aids, the data of which is used for planning a route, and means for assessing the traffic situation, the data of which is used to predict the schedule of movement of an electric vehicle along a route, and the formation of a forecast P _{f is} carried out according to the formula

P _f = (m-vdv / dt + mg-dh / dt + P _w ) / p, where m is the mass of the electric vehicle, v, h are the predicted speed and altitude of the electric vehicle, g is the acceleration due to gravity, P _w is the predicted power losses due to rolling friction and aerodynamic resistance of an electric vehicle, h is the efficiency of the electric drive of the driving wheels of an electric vehicle, and the prediction period P _{f is} set so that it exceeds the value

(E max EshtUR av? Where E _max , E _min are the maximum and minimum possible reserves of energy of the capacitor bank, P _av is the average power P _out when an electric vehicle moves on a highway with a high-quality surface.