RU2797370C1 - Charging system and method for controlling electric vehicle battery charging - Google Patents

Abstract

FIELD: electric vehicle batteries.

SUBSTANCE: group of inventions relates to a charging system and a method for controlling the charging of an electric vehicle battery. The power exchange station for an electric vehicle battery comprises: a power output for the vehicle, a data exchange port, and a plurality of power supplies. The communication port is used to determine whether the vehicle can be charged with AC or DC. The charging current generation system contains: two synchronous three-phase generators and a closed hydrodynamic system. Two hydraulic motors are connected to the pressure line of the hydrodynamic system, the shafts of which are rigidly connected to the generator rotors. The passage of the trigger pulse is carried out by a programmable controller of the upper level in accordance with the control logic, where (→) - a symbol of the sequence of actions: multi-way power key 5, → power DC-AC inverter 3, → power three-phase key R, → frequency converter PID control. The stator windings of the first and second generators are connected to the primary windings of two galvanic isolation transformers. The secondary windings of the first transformer are connected to the inputs of the power three-phase switch S. The secondary windings of the second transformer are connected to the input of the power AC-DC inverter 4. The generation process by both generators starts simultaneously.

EFFECT: purpose is achieved.

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Description

Technical field

The proposed technical solution relates to a generation system with electromechanical energy conversion, and an environmentally friendly method of charging the battery of an electric vehicle.

One of the reasons hindering the development of the fleet of electric vehicles is the limited ability to charge the battery outside the urban cycle. The organization of the appropriate infrastructure on federal and local roads will require significant capital investments, with a very remote payback period. The concept of the proposed technical solution makes it possible to make the possibility of charging the batteries of electric vehicles universally available, subject to legal regulation, and in accordance with the standards of manufacturers.

In this invention, the system of autonomous generation, and the method of charging the battery of an electric vehicle, assumes that the torque to the rotors of synchronous generators, with n-number of stator windings, is imparted by shafts of axial-piston hydraulic motors rigidly connected to them, capable of operating at a pressure of 450 bar, developing a torque torque up to 6000 Nm, at a speed of up to 5000 rpm. The kinetic energy of the pressure of the working fluid is reported by a group of hydraulic pumps with an adjustable inclined block, and the triggering impulse to the electric drives of the pumps is initiated by a pre-charged battery 15, which operates as an energy hub in operating mode.

The greatest increase in the output power and torque on the generator rotor shaft with excitation by high-coercivity permanent magnets (HPM) is achieved by using the Halbach magnetic assembly, which is characteristic in that the HPM magnetized in the radial, tangential or diametral direction form a double magnetic flux of one pole in the air gap, and so same weakened opposite pole.

State of the art

Known Charging system for electric transport (RF patent No. 2722894), where the technical result is to provide the necessary power and energy to operate the system in the area of the absence of the electric current network through the use of fuel cells. The technical result is achieved by the fact that the proposed system of charging stations for electric transport, containing one distribution gas pipeline connecting the main gas pipeline with one fuel cell, which is connected in series with a power line via conductive lines, with one charging station, configured to connect electric transport.

The disadvantage of the above technical solution is the impossibility of its use in places where there is no extensive infrastructure of gas pipelines, which limits its use in essence.

The closest to the proposed technical solution is the System, and the method of control and monitoring of the electric vehicle battery charging complex (RF patent No. 2571847) or DC and a plurality of power supplies, which include an AC power supply and a DC power supply, and a controller for power control.

The disadvantage of the above technical solution is the origin of the primary source of the charging current - this is the power network, that is, a circumstance that limits the possibility of operating electric vehicles outside the urban cycle.

Disclosure of invention

The purpose of the invention is to propose a generation system and a method for controlling the charging of an electric vehicle battery, eliminating the dependence of the origin of the charging current on industrial energy in the part where the generating capacities operate by the type of combustion of fossil fuel resources; propose a way to solve the problem of availability of charging the battery of an electric vehicle outside the urban cycle in places where there are no public electric networks. The system for generating and charging the battery of an electric vehicle is mobile and can be placed on federal and regional highways. The charging generation and control systems are interconnected by a network of service data exchange channels using a satellite modem and a satellite communications operator, such as Iridium, with 100% global coverage. In addition to the main purpose, the implementation of the proposed technical solution in a mobile version can be used in all areas of activity where electrical energy is required.

To achieve the technical result, a system of electromechanical energy conversion with a closed hydrodynamic cycle is proposed, with the possibility of generating an alternating three-phase voltage by two synchronous generators, the torque of which is supplied by hydraulic motors connected in parallel in the pressure line of the hydraulic circuit, and where the working fluid has antifreeze properties.

By external action, electric drives of hydraulic pumps receive an initial electrical impulse from a pre-charged battery. The pressure of the working fluid simultaneously drives two hydraulic motors, the shaft of each of which is rigidly connected to the rotors of two generators, each of which works on its own load in the generation mode. The control of the generation and electromechanical energy conversion, the transfer of the storage charging power to the battery of the electric vehicle, is carried out and monitored in accordance with the control logic of the software stored in the memory of the top-level system programmable controller. The system programmable controller is equipped with an analog-to-digital converter (ADC), a timer, a comparator of analog signals coming from sensors that monitor electromechanical conversion devices, mutual energy transfer and a closed hydrodynamic cycle. Programmable logic controllers of the lower level are subordinated to it, with the ability to compare the operating and reference voltages, form and transfer control actions to a group of actuators, to carry out the process of transferring energy from one device to another continuously, throughout the entire working time, and which cannot be started and completed without external intervention.

The proposed set of devices for electromechanical energy conversion and a method for controlling the charging of an electric vehicle battery contain signs of novelty, industrial applicability and inventive step.

Graphic material:

Fig. 1 Mnemonic scheme of energy conversion.

Fig.2 Scheme of hydraulic drives operating in closed hydraulic cycle mode.

Fig. 3 PID control scheme for a group of pumps.

Description of the graphic material.

Fig. 1 where the letters indicate:

G1 and G2, generators, T1 and T2, transformers, E+F+n, K+L+n- battery modules, where n is the number of cells in the module, R-three-phase power switch, S-three-phase power switch.

The numbers indicate:

1,6,12 - system computing programmable controller and controllers subordinate to it.

15, 16 - storage and consumable batteries.

2 - electric drives of pumps.

3, 4, 14 - current and voltage inverters.

5 - multichannel power switch, 7, 8, 11, 13 - power switches.

9, 10 - ports for connecting the battery of an electric vehicle.

Fig. 1 is a mnemonic block diagram of the cause-and-effect relationships of generating, control and actuating devices containing an AC voltage generation unit, including two synchronous generators G1 and G2 with excitation by high-coercivity permanent magnets and multi-phase stator inductance windings, the rotors of which are driven by two hydraulic motors 21 and 24. The device contains two step-up transformers for galvanic isolation T1 and T2, two power DC-AC inverters 3.4, one AC-AD inverter 14, a three-phase power switch R, a three-phase power switch S, a group of power switches 5,7,8,11 ,13, EV battery connection ports 9,10, two initially charged batteries 15,16, each of which consists of E+F+n and K+L+n modules.

The primary source of energy for the triggering pulse initiated by an external influence is a pre-charged battery 15, which includes (E+F+n) modules, with the ability to transfer its energy to the charging capacity of the battery of an electric vehicle on demand in the operating mode, and to quickly switch from the transmission mode and vice versa, to power consumption. This eliminates the need for simultaneity of the processes of generation and consumption of charging power, that is, that fundamental limitation for ensuring the balance of power, expressed in the law of conservation of energy for the electric circuit, since the generator G2 and the end consumer of the charging power - the battery of an electric vehicle are not interconnected, and separated by the energy storage battery 15. The concept of a starting short-term DC pulse from the primary source is known in the art and has been previously used by the Applicant. [7]

The purpose of the battery 16 is to supply constant voltage to the system programmable controller 1 and its slave controllers 6,12, balancing devices, devices that perform control and switching functions. The source of the charging current for the battery 16 are taps from the secondary windings of the transformer T2. (The functions of the controller 12, AC-DC inverter 14, power switches 11,13 are not conventionally described, the supply voltage lines are not conventionally shown.) Controllers 6 and 12 contain analog programmable comparators, with a sampling rate of approximately 2 Hz, equipped with a reference voltage, control the system active balancing against overcharging and overdischarging of battery cells of blocks and modules that are part of battery 15 and battery 16.

Lead-acid batteries, while having advantages such as a large tolerance of the charging voltage level, large capacity, wide temperature range, have disadvantages, such as a high level of self-discharge, a relatively small number of charge-discharge cycles. Compared to lead-acid batteries, lithium batteries have a high rate of charge-discharge cycles, low self-discharge and high energy density per unit volume. A significant disadvantage of lithium batteries is the flammability of liquid electrolytes. Among the many projects in the field of production technology and improvement of lithium-ion batteries, solid state batteries with a solid electrolyte, with a pure silicon anode, safe in terms of flammability, and more efficient in terms of energy density, with a high charge rate at low temperature, which can be ready to enter the market in the near future. The operating voltage of the battery of an electric vehicle is 400-450 V. The standard for DC charging is 500-900 V, taking into account the compensation for voltage drops over a fixed length of cable connection from the batteries of an electric vehicle.

Fig. 2 where the numbers indicate:

17 - pumping station.

18 - electrically controlled distributor - regulator.

19.20 - safety valve, check valve.

21.24 - hydraulic motors.

22.23 - three-phase voltage generators.

26,27,28 - system for replenishing the working fluid.

25 - heat exchanger.

Fig. 2 explains the organization of the hydraulic circuit, where the high and low pressure hydraulic lines constitute a system with a closed circulation of the working fluid, and where the hydraulic motors 21,24 are connected in parallel and impart torque to the rotors of the generators 22 and 23. The kinetic energy of the working fluid is reported by the axial piston hydraulic pumps 17 of the volume controls, organized in a group according to the “master-slave” scheme, and involve automatic change in the number of pumps in operation, their parallel-sequential inclusion in operation, which makes it possible to create pumping systems of high energy efficiency and functionality that meet constantly changing load conditions. The electrohydraulic control of the lead pump is carried out by means of a high-speed bypass valve (not shown in the diagram), as part of an electrically controlled power distributor-controller 18, with an electronic control system for variables (temperature, pressure, moment of force, flow rate). Compliance with the set values of the variables is ensured by changing the rotational speed of the electric drive shaft of the drive pump, by means of frequency regulation of the supply voltage, which allows soft start-up, reduction of starting currents, and elimination of hydraulic shocks. The hydraulic circuit includes a safety valve 19, a non-controlled check valve 20. Compensation for leakage of the working fluid is provided by an additional make-up hydraulic system, including a make-up pump 28, an overflow valve 26 that maintains a constant make-up pressure in the drain line, the working fluid is cooled by a heat exchanger 25. liquid is discharged into tank 27. The start of rotation of the generator rotors requires a large torque (breakaway moment), the value of which determines the ability of the hydraulic motor to start the load. The frequency of rotation of the hydraulic motor shaft depends on its working volume and pump flow.

Fig. 3 shows the control scheme for electric drives of pumps based on a frequency converter, which includes a built-in programmable controller (PID) - regulation, which allows you to select the lead pump, and by controlling the slave pumps, through direct and feedback lines (conditionally not shown), regulate and maintain control given parameters of torque, speed, pressure and flow rate of the working fluid in the pressure line. The analog inputs of the PID control comparator are connected to temperature sensors, pressure sensors, a torque load cell, a Hall sensor for controlling the flow rate of the working fluid. The limits of the required values of the effective three-phase voltage, current, power, frequency and phase difference, speed, are set by the system programmable controller 1. The system programmable controller 1 compares the feedback signals with the values of the controlled parameters specified by the logic program, and generates control signals to the frequency converter to increase or reducing the frequency of the supply voltage of electric drives until the controlled parameters approach the specified values. The components of a PID control signal are the sum of three components: proportional, integral, and derivative. The resulting signal at the output of the PID controller takes into account the actual value, the set value, the difference in values and the rate of change of the controlled characteristics. Among the set values of the parameters, it is possible that when all the elements of the storage batteries are charged, and it becomes necessary to safely neutralize the energy of the magnetic field of the generators by reducing the number of revolutions of the rotors until the power switch breaks the charging circuit. The accuracy and speed of positioning is achieved by the selection of coefficients: Kp-proportional, Ki-integral, Kd - differential components.

In the first approximation, the coefficients are determined using a mathematical model of the automatic control system (ACS), then they are selected empirically, in relation to the object. The use as a leading axial-piston hydraulic pump with an adjustable working volume by changing the angle between the axis of the cylinder block and the drive shaft makes it possible to regulate the speed of the hydraulic motor shaft in a wide range. When the master and slave pumps are switched on in series, their combined pressure is summed up, the flow remains at the level of one pump. When the master and slave pumps are connected in parallel, their supply is summed up, the pressure remains at the level of one pump. The potential of PID control allows expanding the possibilities for maintaining setpoints in a closed hydraulic system in its pressure section.

To achieve a technical result on the generation of charging power and the method of controlling the charging of a vehicle battery, a sequence of the following events is necessary.

At the moment of start-up of battery 15, battery 16 are initially charged, power switches 5,7,8,11,13,R,S- are normally closed. External action system programmable controller 1, in accordance with a logical sequence of events, initiates a trigger pulse.

Event 1 - launch.

To transmit the triggering pulse, the system controller 1, by its control action, switches the three-phase power switch R to the “open” position, and the controller 6 subordinate to it switches the state of the multi-channel power switch 5 to the “open” position for the AC-DC inverter 3.

Consequence of event 1.

The pre-charged battery 15 is discharged to the DC-AC 3 power inverter, the AC outputs of which are connected to the frequency converter for the PID control of the electric drives of pumps 2. At the same time, the controller 6 switches the power switch 5 to the "closed" position for DC-AC 3, and to the position "open" for the AC-DC4 power inverter, and at the same time, the system controller 1 closes the three-phase power switch R, and opens the three-phase power switch S.

Event 2

The starting short-term impulse of direct current from the primary source - AKB15, the duration of which is determined by the capacity of the primary source and the power consumption of the electric drive, is converted by the DC-AC3 power inverter into a three-phase alternating current, which causes a reaction in the hydraulic system, where the kinetic energy of the working fluid drives the hydraulic motors 21,24, reporting torque to the rotors of generators 22.23. The rate of transmission of the hydraulic impulse (the pressure of the working fluid, which is converted into work) in closed hydraulic systems in radian terms is 10,000 rad/s ² , in linear terms, approximately 1200 mm/s.

Consequence of event 2.

The start of the operating mode of generating a three-phase voltage by the generator G1, which supplies the electric drives of 2 pumps 17. Simultaneously, the generator G2 starts to generate a three-phase voltage to charge the battery 15 and battery 16.

The charge level of each of the E+F+n modules of the battery 15 is carried out by the controller 6, relative to the level of charge capacity values that preceded the start of the device. To transfer the energy of the charging power of the battery 15 connected to the battery of the electric vehicle, a data transmission channel is organized between the interfaces of the controller 6 and the electric vehicle, on the basis of which the type and current state of the battery of the electric vehicle are established, while the system allows increasing the required electric power.

The control of the energy transfer of the charging capacity from the battery 15 to the battery of the electric vehicle is performed by the system computational programmable controller 1, which, by means of a control action on the controller 6 subordinate to it, opens the power switches 5,7,8, with the ability to switch to the cell charging mode during the active balancing process and modules that transferred charge energy, regardless of those cells and modules that were simultaneously switched to the charge energy transfer mode. When the charging capacity of the electric vehicle battery reaches more than 80%, the process of transferring the energy of the charging capacity is interrupted, the AKB15 modules switch to the recharging mode. Compared to other methods, DC charging an electric vehicle battery takes significantly less time. The computing module of the controller 1, through the established data transmission channel, certifies the availability of charging power according to the declared charging rate, on which the cost of the service depends.

A mobile generation system installed in places remote from public electric networks, organized according to a block-modular scheme, placed in a climate container on a wheeled platform, and covered by a network of streaming data exchange with the ability to display geolocation, make banking transactions, remotely monitor the readings of connected sensors , inform about the degree of charge, the absence or presence of an emergency in the generation system, or overheating, overcharging, overdischarging of storage batteries.

The operation of the mobile generation system and the method of charging the battery of an electric vehicle does not entail environmental consequences.

The present invention is not limited to the above description, and technological and circuitry options are always possible, therefore, the lack of thoroughness of the essence of the invention should not be considered as limiting the scope of priority protection, which is determined by the attached claims.

Literature:

1. A. Pycy. Pulse current conversion. Part 2. Radiopilot magazine, July 2017

2. Dejan Schreiber. Power converting devices. Magazine Components and Technologies, No. 2009

3. Kevin Krause. Modern energy storage systems. Control Engendering magazine, Russia, published April 2020

4. Encyclopedia of APCS: 5. PID controllers, APCS: 6 Controllers.

5. Nesterenko G.B. Dynamic control of Smart Crid modes using energy storage devices. Novosibirsk State Technical University. Master's dissertation. 06/08/2018

6. Gustov D.Yu. Hydraulics and drives. Methodical instructions. National Research Moscow State University. Moscow 2020

7. RU 104120 03. December 2010 Burmatov E.P. Turbine generator with a closed hydrodynamic cycle for the movement of an electric vehicle. with an electric vehicle.

8. RU 2561826 October 09, 2015 Sidorenko O.I. Battery of electric energy storage devices with a distributed analytical control system.

Claims (8)

1. An electric vehicle battery charging system, where the power exchange station for the electric vehicle battery comprises a power output for the vehicle, a communication port for determining the ability of the vehicle to be charged by AC or DC, and a plurality of power sources, characterized in that the charging current generation system is of two synchronous three-phase generators, contains a closed hydrodynamic system, where two hydraulic motors are connected to the pressure line, the shafts of which are rigidly connected to the rotors of the two generators, and the kinetic energy of the working fluid is provided by the electric drives of the pumps, organized according to the master-slave scheme, which at the time of launch receive the initial electrical impulse from a pre-charged battery, consisting of E + F + n modules, where n is the number of elements in the module, while the passage of the triggering impulse is carried out by the upper-level programmable controller, in accordance with the control logic, where (→) is the symbol for the sequence of actions : multi-pass power switch (5), → DC-AC power inverter (3), → three-phase power switch R, → PID control frequency converter, and the stator windings of the first and second generators are connected to the primary windings of two galvanic isolation transformers, which can be step-up, and the secondary windings of the first transformer are connected to the inputs of the power three-phase switch S, while the secondary windings of the second transformer are connected to the input of the power AC-DC inverter (4), while the generation process by both generators starts simultaneously. 2. The system according to claim 1, characterized in that the hydraulic power distributor is controlled by a PID controller, where the initial control parameters are set by a system programmable controller (1) of the upper level, and the actual values of the adjustable parameters are reported by sensors for monitoring variable components. 3. The system according to claim 1, characterized in that the effect of the triggering pulse stops from the moment the system programmable controller (1) switches the three-phase power switches to the R-closed, S-open positions, and where the operating mode of the first and second generators immediately begins. 4. The system according to claim 1, characterized in that the power AC-DC inverter (14) is connected to the taps of the secondary windings of the transformer T2, the primary windings of which are connected to the stator windings of the second generator, and the energy of the charging capacity of the second battery (16) is a source reference voltage, power supply for system devices, including electromechanical energy conversion control sensors, hydrodynamic process control sensors, switching devices, metering and data storage devices, with the ability to monitor the operating state of the system. 5. The system according to claim 1, characterized in that it is mobile, organized according to a block-modular scheme, placed in a climatic container on a wheeled platform and covered by a network of streaming data exchange, with the ability to display geolocation, make banking transactions, remotely control the readings of connected sensors , with the possibility of informing about the degree of charge of the energy storage devices, the absence or presence of an emergency, while the energy of the charging capacity of the storage battery (15) is transferred to the battery of the electric vehicle on demand, while the system allows an increase in electric power. 6. A method for controlling the charging of an electric vehicle battery, characterized in that it is implemented in the form of software for a sequence of logical events recorded in the ROM of the system programmable controller (1) of the upper level, while the control actions, based on the results of logical events, are performed by the programmable controllers subordinate to it ( 6, 12) of the lower level, equipped with analog signal comparators, where, according to the results of measurements, the balancing devices during the charging process equalize the voltages of the battery cells and modules that are part of the storage battery, while the controllers (6, 12) have access to each cell and module, where those who gave their charge energy are switched by them to the charge mode, regardless of those cells and modules that at that moment of time give charge energy, and the alternation of charge and transfer of charge energy to the battery of the electric vehicle is maintained and performed continuously, during the entire working time, and the working the mode can be started or ended by an external influence. 7. The method according to claim 6, wherein the lower level controllers are controlled by preset parameters related to the storage battery and the battery of the electric vehicle. 8. The method according to p. 6, containing the ability to control the output of the generators from the operating mode until the charging circuit breaks.

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