EP4638877A1

EP4638877A1 - Hybrid power supply system with galvanic separation and method of operation of such system

Info

Publication number: EP4638877A1
Application number: EP23853639.5A
Authority: EP
Inventors: Mieczyslaw SKALNIAK; Piotr JASHARI
Original assignee: Tophoe Polska Spolka Z Ograniczona Odpowiedzialnoscia
Current assignee: Tophoe Polska Spolka Z Ograniczona Odpowiedzialnoscia
Priority date: 2022-12-20
Filing date: 2023-12-15
Publication date: 2025-10-29
Also published as: WO2024136688A1; PL443193A1

Abstract

The invention relates to a hybrid power supply system with galvanic separation and a method of operation of such a system, designed in particular for multipurpose machines, excavators, demolition robots, enabling the aforementioned machines to work independently of the power supply method. The hybrid power supply system with galvanic separation designed in particular for multipurpose machines which is equipped with a phase connector (105), a traction battery (305), and, optionally, additionally with a DC/DC converter (320), at least one electric motor (400) which drives a hydraulic pump (505) and the pump combined with a hydraulic distributor (510) transfers hydraulic oil to receivers in the multipurpose machine which are responsible for the operation of the working and drive system. The said electric motor (400) is connected to an inverter (315) and is controlled by the inverter (315), and the system is equipped with at least one electronic control unit ECU (600) responsible for the control of individual elements of the system. The said phase connector (105) is a connector located either upstream a network interference filter EMI (110), which is in turn located between the phase connector (105) and at least one or more AC/DC converters (200), where galvanic separation takes place, and/or through an alternating current AC phase separator (115), wherein the AC/DC converters (200), on the DC side, are connected to the traction battery (305), the inverter (315) and, optionally, additionally to the DC/DC converter (320).

Description

HYBRID POWER SUPPLY SYSTEM WITH GALVANIC SEPARATION AND METHOD OF OPERATION OF SUCH SYSTEM

Description

FIELD OF THE INVENTION

The subject matter of the invention relates to a hybrid power supply system with galvanic separation and a method of the operation of such a system designed in particular for multipurpose machines, excavators, demolition robots, which allows the aforementioned machines to operate regardless of the power supply method.

The present solution according to the invention generally relates to the field of mechanical drive systems, and in particular it relates to the field of mechatronics which combines elements of mechanics and electronics. The invention is focused on a hybrid power supply system comprising a combination of a hydraulic gear and electric drive used to power multipurpose machines, basically machines, equipment requiring high power demand.

BACKGROUND OF THE INVENTION

Basically, multipurpose machines, such as for example heavy construction and demolition machines but not only, require unfailing, in particular constant and reliable power supply. There are available various power supply systems designed for multipurpose machines. The operation of such multipurpose machines is possible through external power supply, most frequently from a 3 -phase network or through power supplied from a traction battery or through hybrid solution; currently known hybrid solutions usually have two motors, two pumps and they operate separately i.e., either one system operates, e.g. powered by a traction battery, or the other system powered by alternating current AC.

DESCRIPTION OF THE PRIOR ART

One solution known in the prior art is a power supply system used in combustion machines where, in the case a machine is powered with current, the so-called Power-Pack system is used with a build-in replacement hydraulic system driven by an electrical engine, which in turn is powered from a 3 -phase network. Typically, when a machine is equipped with a traction battery, it cannot operate using external power supply and its operation is powered from the traction battery, and after it has been discharged, the machine is stopped for the time of charging the battery. Power-Pack is a group of systems which constitutes a fast-replaceable module integrating the engine, the gear box and mechanisms designed to provide the vehicle with necessary media. The compact structure and use of a mounting frame increases the operational flexibility of the drive unit. The autonomous structure simplifies disassembly and consequently minimizes replacement time in the event of failure.

In the prior art there is known the American patent No. US 6,126,401 B2 titled "Hybrid electric/hydraulic drive system " which discloses a hybrid electric hydraulic drive system having a first cylinder having a left chamber and a right chamber separated by a piston. A second cylinder has a single or sole chamber for receiving hydraulic fluid with the second cylinder enclosing a second piston. The second piston is substantially equal in length to the first cylinder and is rigidly attached to the first cylinder. A pump is fluidly connected to the left chamber by a first fluid passage and is fluidly connected to the right chamber by a second fluid passage. A third fluid passage is directly connected to the right chamber and to the sole fluid chamber of the second cylinder. A first rod is connected to the first piston, and a second rod is connected to the second piston. The first and second rods are connected by a connecting element so the rods move in unison. The volume of the sole chamber is equal to the volume of the first rod with the total fluid capacity of the system remaining constant during operation. An encoder is electrically connected to a controller which is electrically connected to a servo electric motor which drives the pump.

Furthermore, in the prior art there are also known American patent applications, including American patent application No. US2017305276 Al titled "Electro-hydraulic hybrid system" and American patent application no. US2008251302 Al titled "Hydro- Electric Hybrid Drive System For Motor Vehicle" and another American patent application No. US2017306588 Altitled "Portable power supply system for an electrically driven work machine and a work machine equipped with such a power supply system ", which basically present the electronic structures of hybrid power supply systems.

The above-described prior art solutions and, more broadly, solutions relating to power supply systems are highly developed in terms of required subassemblies. That is why, the engine/pump assembly in the present drive systems with a hybrid drive integrated with the drive system is relatively big, heavy and cumbersome. Therefore, it is the intention of the present invention to overcome these shortcomings of the prior art and, more specifically, to overcome certain limitations in respect of hybrid power supply systems, with particular emphasis on solutions enabling operation with 1 -phase, 3-phase power supply from a traction battery. Additionally, in the prior art there is a lack of a hybrid power supply system with galvanic separation intended in particular for multipurpose machines.

SUMMARY OF THE INVENTION

The object of the invention is to develop a totally novel solution in the form of a hybrid power supply system with galvanic separation and a method of operation of such a system intended in particular for multipurpose machines.

The essence of the invention is a hybrid power supply system which does not require the use of duplicated subassemblies, such as motors, pumps, etc. enabling the operation of the working system or operation of the drive system while the multifunction machine is moving. The system does not require an additional Power-Pack system, either. Additionally, the system enables operation with an external 1 -phase or 3 -phase power supply and a mounted traction battery, during which operation, in a normal working cycle of a multipurpose machine, the traction battery is recharged or, in the case of operation with 1 -phase power supply, it is possible to draw additional energy from the traction battery. In this case, the multipurpose machine will be either faster or more powerful, depending on the preferences of the manufacturer of the multipurpose machine and appropriate settings of the on-board computer ECU (also called an electronic control unit) that controls the operation of the multipurpose machine.

Importantly, in the case of the claimed solution, the traction battery can be charged not only during operation, as indicated above, but already after connecting 1- phase of 3-phase power supply, i.e., the machine does not need to be in the state of operation for the traction battery to be charged.

The object of the invention in therefore to develop a hybrid power supply system with galvanic separation, designed in particular for multipurpose machines, which is independent of the source of supply of both direct current DC and 1 -phase alternating current AC and 3-phase alternating current AC and which solves a technical problem of selecting the power supply for the machine at the site of its operation, considering the fact that works are often carried out at sites where access to 3-phase or even 1 -phase power supply is difficult or even impossible.

The solution according to the invention also solves a technical problem of increasing machine mobility in difficult working conditions by the system operating with power supply from a traction battery.

Additionally, the hybrid power supply system provides galvanic separation which makes it possible to reduce the risk of interference and protect electronic circuits against high voltages; in other words, it makes it possible to protect the users and electronic circuits as such against high voltage. By limiting ground loops, i.e., current flow between devices that communicate with each other, signal integrity is improved and consequently the electromagnetic compatibility of the multipurpose machine in which it is used.

The essence of the invention is defined by a hybrid power supply system with galvanic separation designed in particular for multipurpose machines according to claim 1. Dependent claims 2-9 relate to individual embodiments of the invention according to claim 1. Claim 10 defines a method of operation of the hybrid power supply system with galvanic separation designed in particular for multipurpose machines according to claim 1. Dependent claims 11-13 relate to individual embodiments of the invention according to claim 10.

In order to achieve the above purposes, according to one aspect of the invention, the invention provides a hybrid power supply system with galvanic separation designed in particular for multipurpose machines which is equipped with a phase connector, a traction battery and, optionally, additionally a DC/DC converter, at least one electric motor which drives a hydraulic pump and the pump combined with a hydraulic distributor transfers hydraulic oil to receivers in a multipurpose machine which are responsible for the operation of the working system and the drive system, wherein the electric motor is connected to an inverter and is controlled by the inverter, and the system is equipped with at least one electronic control unit ECU responsible for the control of individual elements of the system, characterized in that the phase connector is located either upstream a network interference filter EMI, which is located between the phase connector and at least one or more AC/DC converters where galvanic separation takes place, and/or through an alternating current AC phase separator, wherein AC/DC converters, on the DC side, are connected to the traction battery, to the inverter and, optionally, additionally to the DC/DC converter.

Preferably, the said phase connector is a 3 -phase connector that enables connecting a 1 -phase conductor as well as connecting a 3 -phase conductor.

Preferably, the said electric motor is a brushless permanent magnet synchronous motor PMSM or a brushless direct-current motor BLDC.

Preferably, the said connection between the electric motor and the hydraulic pump is carried out through a spline or through a coupling and bell connector or directly on the shaft of the electric motor or through the shaft of the hydraulic pump in the socket of the electric motor or in any other way that can transfer the rotational movement of the electric motor to the rotational movement of the hydraulic pump. Preferably, the said AC/DC converters are connected with each other in parallel and are mounted in the multipurpose machine or outside the multipurpose machine.

Preferably, the said electric motor has the power of from 0.1% to several per cent less than the power supplied from the AC/DC converters.

Preferably, the said traction battery preferably has different capacities and is made in a technology ensuring large energy accumulation per litre or kilogram, preferably in LiFePo4 technology.

Preferably, the said traction battery has the same voltage as the voltage to which the AC/DC converters convert alternating current AC to direct current DC.

Preferably, the said hybrid system is equipped with an additional source of DC power supply in the form of a battery for exciting the traction battery.

According to one of the aspects of the invention, the invention provides a method of operation of the hybrid power supply system with galvanic separation designed in particular for multipurpose machines, consisting in that the type of power supply to the multipurpose machine in selected at the workplace where operation with an external power supply through a phase connector and with a mounted traction battery is provided, during which operation in a normal working cycle the traction battery is recharged or, in the case of operation with 1 -phase power supply, additional energy is taken from the traction battery in order to increase either the speed or power of the multipurpose machine based on the preferences of the manufacturer of the multipurpose machine, which are set by at least one electronic control unit ECU by means of which the operation of subassemblies and the multipurpose machine are controlled.

Preferably, the said traction battery is charged during the working cycle of the multipurpose machine when powered from both 1 -phase and 3 -phase network or when connected to any other external power supply with which the multipurpose machine is powered; the greater the difference between the power from the AC/DC converters and the electric motor, the greater power is redirected to charge of the traction battery while the electric motor operates at full load.

Preferably, the said traction battery is excited by an additional source of DC power supply in the form of a battery.

Preferably, a converter designed to control the electric engine is used to convert direct current DC to alternating current AC with adjustable initial frequency thus ensuring a precise control of the input value for the electric motor. The solution provided according to the above proposed aspect ensures an efficient hybrid power supply system, which basically makes it possible to limit the number of necessary subassemblies while prolonging the life of other elements of the system. Additionally, the invention is able to overcome higher operating costs because the invention can be initially manufactured for novel machines thus limiting the doubling of subassemblies or it can be installed in existing machines without costly modifications of such systems.

One unquestionable advantage of the claimed solution in the form of the hybrid power supply system it that it is also possible to adjust it to already existing multipurpose machines. Additionally, it can be used in industries other than the construction or demolition industry, e.g., in agricultural, mining and military machinery, autonomous and semi-autonomous vehicles.

Another advantage of the proposed invention is reduction of the demand for electricity during the start-up of high-power electrical systems, mainly the motor. In standard motors, the so-called SoftStart is used during the start-up and, despite this, the motor needs the power supply to enable draw of high-voltage current up to several dozen amperes (e.g., 60A and more). The claimed solution enables operation even with power supply from a one-phase network with access to 16 A.

In light of the above, the solution makes it possible to limit, and even eliminate, the possibility of adverse phenomena of surge current and torque impact. Surge current is characterized by a sudden increase of current with simultaneous decrease of voltage, which may lead to damage of installation(s) and electrical devices powered from this circuit. A mechanical impact, on the other hand, relates to drive systems where a dynamic jerk can cause damage thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the invention is presented in the embodiment in relation to the attached drawings wherein:

FIG. 1 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a traction battery according to the embodiment of the invention;

FIG. 2 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 1 -phase network according to the embodiment of the invention; FIG. 3 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 3 -phase network according to the embodiment of the invention;

FIG. 4 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 3 -phase network with the use of an alternating current AC phase separator according to the embodiment of the invention

DETAILED DESCRIPTION OF THE INVENTION

The subject matter of the invention is described in detail below with reference to the attached figures and embodiments. The invention is not limited only to the detailed embodiments described herein.

The hybrid power supply system with galvanic separation designed in particular for multifunction machines, is illustrated in FIGURES from FIG. 1 to FIG. 4. One example of a multifunction machine in which the said hybrid power supply system according to the invention has been installed is a mini excavator.

Basically, the subject hybrid power supply system according to one embodiment is equipped with a phase connector 105, a network interference filter EMI 110, a phase separator 115 of alternating current AC, AC/DC converters 200, a traction battery 305, DC/DC converters 320, an inverter 315, an electric motor 400, a hydraulic pump 505, a hydraulic distributor 510, and an electronic control unit ECU 600 responsible for the control of individual elements of the system as specified below in the description in relation to FIG. 1.

In one embodiment according to the invention, the electric motor 400 is a brushless permanent magnet synchronous motor PMSM. In another embodiment, a brushless direct-current motor BLDC can be used. The electric motor 400 drives the hydraulic pump 505 and the pump combined with the hydraulic distributor 510 transfers hydraulic oil to receivers in a multipurpose machine which are responsible for the operation of the working or drive system. In another embodiment, the working system is as a rule based on hydraulics whereas the rotation of, for example, the excavator tower / head mast or drive can be equipped with electric motors. The connection between the electric motor 400 and the hydraulic pump 505 in the embodiment is carried out by means of a spline. Nevertheless, this connection, depending on what torque Nm the engine is to transfer, can also be carried out in other embodiments by means of a clutch and bell connector or directly on the shaft of the electric motor 400 or through the shaft of the hydraulic pump 505 in the socket of the electric motor 400. The said electric motor 400 is connected to the inverter 315 and is controlled by the inverter 315 and converts direct current DC to alternating current AC with adjustable output frequency thus ensuring a precise control of the input value for the electric motor 400. The electric motor 400 has the power of from 0.1% to several per cent less than the power supplied from the AC/DC converters 200, which, in the case of a surplus of energy from the AC/DC converters 200, makes it possible to charge the traction battery 305 with the power resulting from the surplus. The greater the difference between the power from the AC/DC converters 200 and the electric motor 400, the greater power can be redirected to charge the traction battery 305 while the electric motor 400 is fully loaded. For example, according to the invention, when the AC/DC converters 200 supply 15kW and the electric engine 400 at full load consumes lOkW, this means that 5kW can be redirected to charge the traction battery 305.

The phase connector 105 is a 3-phase connector which makes it possible to connect a 1 -phase conduit and to connect a 3-phase conduit. The said phase connector 105 is a connector that is situated upstream the network interference filter EMI 110, which is in turn situated between the phase connector 105 and the AC/DC converters 200, which convert alternating current AC to direct current DC of a set value.

In the case the network interference filter EMI 110 is designed to reduce the emission of electromagnetic field improving the electromagnetic compatibility of the multipurpose machine and to separate the phases of alternating current AC, the system does not need the alternating current AC phase separator 115 designed to separate alternating current AC phases. And in the case the network interference filter EMI 110 is designed solely to reduce the emission of electromagnetic field improving the electromagnetic compatibility of the multipurpose machine without the function of separating alternating current AC phases, the alternating current AC phase separator 115 designed to separate alternating current AC phases is necessary for use in the system.

The hybrid power supply system, as mentioned above, also requires the use of AC/DC converters 200 converting alternating current AC to direct current DC of a set value - the target values can amount to e.g., 144V, 72V, 48V, etc. In the embodiment, three AC/DC converters 200, which have the power of 3.3kW each and which are connected with each other in parallel thus obtaining 9.9kW power and 144V current have been used. Alternating current AC is supplied to the AC/DC converters 200 and downstream the AC/DC converters 200 there is direct current DC. The AC/DC converters 200, on the DC side, are connected with the traction battery 305, the DC/DC converter 320 and the inverter 315. Another embodiment uses one AC/DC converter 200 with a correspondingly higher power relative to the above defined embodiment with three AC/DC converters 200. This depends on the size of multipurpose machines.

Galvanic separation takes place at the level of the AC/DC converters 200. Galvanic separation, or galvanic barrier or, in other words, galvanic isolation is isolation between at least two functional blocks of the electrical system such that electric current does not flow directly from one block to the other. In the presented electrical diagrams from FIG. 1 to FIG. 4, galvanic separation is a respectively marked dashed line running along the AC/DC converters 200.

In one embodiment, the traction battery 305 has the same voltage as the voltage to which the AC/DC converters 200 convert alternating current AC to direct current DC. Basically, the traction batter 305 has a capacity on the order of 67.6Ah and is made in LiFePo4 technology ensuring high energy cumulation per litre or kilogram. In another embodiment, there would have to be an additional DC/DC converter, e.g., an AC/DC converter with a voltage of 144V and a traction battery with a voltage of 72V, between the AC/DC converter 200 and the traction battery 305, and then there should be a DC/DC converter with a voltage of 144 V/72 V between the AC/DC converter 200 and the traction battery 305.

Furthermore, in the embodiment of the invention, an additional source of DC power supply is used for exciting the traction battery 305. The said additional source may be required to excite the traction battery 305, but it may not always be required - it depends on the type and kind of traction battery 305. In the embodiment, such a source is a 12V gel battery 830 having 7 Ah capacity.

The presented multifunction machine equipped with the hybrid power supply system also enables operation with a connected external power supply, during which operation the traction battery 305 can be charged. When the traction battery 305 is not discharged, the electric motor 400 can draw more power than the 1 -phase network assumes by supplementing the missing power from energy. In a typical working cycle, the traction battery 305 is also re-charged.

FIG. 1 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from the traction battery 305 according to one embodiment of the invention. In this case, direct current DC is transferred from the DC/DC converter 320 to the inverter 315. The inverter 315 transforms direct current DC to alternating current AC with variable frequency and controls the electric motor 400. The electric motor 400 is connected through a spline to the hydraulic pump 505. The electric motor 400 drives the hydraulic pump 505 and the pump transfers hydraulic oil from the hydraulic pump 505 to the hydraulic distributor 510. The hydraulic distributor 510 is in turn connected to receivers (not shown), like an actuator etc., which are responsible for e.g., closing the bucket or lifting the arm of an excavator or a robot, depending of what machine the subject hybrid power supply system is used in. The DC/DC converter 320 converts current, in this case e.g., from 144V to 24V, and this current powers subassemblies such as machine lighting 705, horn 710, buzzer 715, radiator fan 720, display 725 and elements responsible for the control of the machine, like joysticks 800, pedals 805, BT CAN (optionally Wi-Fi) 815 or elements responsible for the communication of CAN 810 with the electronic control unit ECU 600. The 24V/12V DC/DC converter 825 converts current from 24V to 12V and this current powers two electronic control units ECU 600. In this case, the AC/DC converters 200 do not supply current to the system but it is provided straight from the traction battery 305. The traction battery 305 is not charged because an additional source of energy from a 1-phase or 3- phase power supply is not provided.

FIG. 2 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 1-phase network according to an embodiment of the invention. In this case, 1-phase alternating current AC is supplied to the multipurpose machine through a phase connector 105 and then is transferred to the network interference filter EMI 110 which, apart from reducing the emission of electromagnetic field improving electromagnetic compatibility of the multipurpose machine, also has the function of an alternating current AC phase separator. Then, the current is transferred directly to the AC/DC converter 200 - in this case one of three converters (2 of the 3 AC/DC converters do not operate - they are not provided with any phase). The current is converted from alternating current AC to direct current DC, in this case having the value of 144V (or any other values depending on the traction battery 305, e.g., 72V, 48V etc.). Direct current DC is transferred to the DC/DC converter 320, the inverter 315 and the traction battery 305. Other operation and elements of the system are the same as described above in the block diagram with reference to FIG.l. Nevertheless, in this case, when the electric motor 400 does not use the full power that is provided by the AC/DC converter 200, it is used to charge the traction battery 305. The traction battery 305 is charged because an additional source of energy from a 1-phase power supply is provided. Importantly, the greater the difference between the power from the AC/DC converters 200 and the electric motor 400, the greater power is redirected to charge the traction battery 305 when the electric motor 400 is at full load. In summary, when 1-phase power supply is connected and the multipurpose machine does not operate, the traction battery 305 is charged with current up to 3.6kW (as much as the 1-phase network allows) - in the subject multipurpose machine it amounts to 3.3kW due to the power of the AC/DC converter 200. FIG. 3 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 3 -phase network according to an embodiment of the invention. 3-phase alternating current AC is supplied to the multipurpose machine through the phase connector 105 and is transferred to the network interference filter EMI 110 and then it is separated into 3 separate phases to power AC/DC converters 200 - in this case three converters. The current is converted from alternating current AC to direct current DC 144V (or any other depending on the traction battery used, e.g., 72V, 48V, etc.). The DC direct current is transferred to the DC/DC converter 320, the inverter 315 and the traction battery 305. In this case, the AC/DC converters 200 are connected in parallel and thus their total power is greater than the power of a single AC/DC converter or if they were connected in a series. Each phase powers one AC/DC converter 200. Other operation and elements of the system are the same as described above in the block diagram in relation to FIG. 1 and FIG. 2. In the case the electric motor 400 does not use the full power that is supplied by an AC/DC converter 200, it is used to charge the traction battery 305.

FIG. 4 shows an electrical diagram of the hybrid power supply system with galvanic separation operating with power supply from a 3-phase network with the use of the alternating current AC phase separator 115 according to the embodiment of the invention. 3-phase alternating current AC is supplied to the multifunction machine in a similar way as in the electrical diagram of FIG. 3, the difference being that the separation of phases takes place not in the network interference filter EMI 110 but in the alternating current AC phase separator 115 located downstream the EMI filter. In summary, the separation alternating current AC phases in the hybrid system can take place in the network interference filter EMI 110 or farther in the alternating current AC phase separator 115. The remaining operation and elements of the system are the same as described above in the block diagram in reference to FIG. 1, FIG. 2 and FIG. 3. In the case the electric motor 400 does not use the full power that is supplied by the AC/DC converter 200, it is used to charge the traction battery 305.

In summary, in the case from both FIG. 3 and FIG. 4, when connecting to 3- phase power supply and when a multipurpose machine does not operate, the traction battery 305 is charged with current over 3.6kW (as much as the AC/DC converters 200 and the 3-phase network allow); in the subject machine it is 9.9kW due to the power of the AC/DC converters 200 which amounts to 9,9kW in total.

The above description of presented embodiments has been provided in order to enable any person skilled in the art to carry out or use the invention. Various modifications of the embodiments presented are also possible, comprising all such changes, modifications and variants that fall within the essence and scope of the appended claims. The basic principles set out herein may therefore be applied in other embodiments without going beyond the scope of the invention. Thus, the invention is not intended to be limited to the embodiments presented herein but to accord with the widest scope consistent with the principles and novel features set out herein.

The solution according to the invention thus offers, with the use of the above- mentioned technical means as indicated in the description and in the Figures, a hybrid power supply system with galvanic separation designed in particular for multipurpose machines using the designed elements and circuits. APPLICATION OF THE INVENTION

The invention can be applied in many industries, including the construction or demolition industry, in which the hybrid power supply system can be used, in particular in multipurpose machines such as excavators, demolition robots, enabling such machines to operate independently of the power supply method, as well as in the broadly defined agricultural, mining or military industry, basically in machinery and equipment with high power requirements, as well as in autonomous and semi-autonomous vehicles.

Importantly, the claimed solution in the form of the hybrid power supply system can be adapted to already existing multipurpose machines and thus not only to new manufactured machines but also to those already manufactured.

LIST OF REFERENCE NUMBERS

105 phase connector

110 network interference filter EMI

115 alternating current AC phase separator

200 AC/DC converter

305 traction battery

320 DC/DC converter

315 inverter

400 electric motor

505 hydraulic pump

510 hydraulic distributor

600 electronic control unit ECU

705 lights

710 horn

715 buzzer

720 fan

725 display

730 temperature sensor

800 joysticks

805 pedals

810 CAN TO

815 BT CAN

820 REMOTE CONTROL

825 DC/DC Converter 24V/12V

830 battery 12V

Claims

1. A hybrid power supply system with galvanic separation designed in particular for multipurpose machines which is equipped with a phase connector (105), a traction battery (305), and, optionally, additionally a DC/DC converter (320), at least one electric motor (400) which drives a hydraulic pump (505) and the pump combined with a hydraulic distributor (510) transfers hydraulic oil to receivers in a multipurpose machine which are responsible for the operation of the working and drive system , wherein the electric motor (400) is connected to an inverter (315) and is controlled by the inverter (315), and the system is equipped with at least one electronic control unit ECU (600) responsible for the control of individual elements of the system, characterized in that the phase connector (105) is a connector located either upstream a network interference filter EMI (110), which is in turn located between the phase connector (105) and at least one or more AC/DC converters (200), where galvanic separation takes place, and/or through an alternating current AC phase separator (115), wherein AC/DC converters (200) on the DC side are connected to the traction battery (305), to the inverter (315) and, optionally, additionally to the DC/DC converter (320).

2. The hybrid power supply system according to claim 1 , characterized in that the phase connector (105) is a 3-phase connector that enables connecting a 1-phase conductor as well as connecting a 3-phase conductor.

3. The hybrid power supply system according to claim 1, characterized in that the electric motor (400) is a brushless permanent-magnet synchronous motor PMSM or a brushless direct-current motor BLDC.

4. The hybrid power supply system according to claim 1 or 3, characterized in that the connection between the electric motor (400) and the hydraulic pump (505) is carried out through a spline or through a coupling and bell connector or directly on the shaft of the electric motor (400) or through the shaft of the hydraulic pump (505) in the socket of the electric motor (400) or in any other way that can transfer the rotational movement of the electric motor (400) to the rotational movement of the hydraulic pump (505).

5. The hybrid power supply system according to claim 1, characterized in that the AC/DC converters (200) are connected to each other in parallel and are mounted in the multipurpose machine or outside the multipurpose machine.

6. The hybrid power supply system according to claim 1 or 5, characterized in that the electric motor (400) has the power of from 0.1% to several per cent less than the power supplied from the AC/DC converters (200).

7. The hybrid power supply system according to claim 1, characterized in that the traction battery (305) preferably has different capacities and is made in a technology ensuring large energy accumulation per litre or kilogram, preferably in LiFePo4 technology.

8. The hybrid power supply system according to claim 1 or 7, characterized in that the traction battery (305) has the same voltage as the voltage to which the AC/DC converters (200) convert alternating current AC to direct current DC.

9. The hybrid power supply system according to claim 8, characterized in that it is equipped with an additional source of DC power supply in the form of a battery (830) for exciting the traction battery (305).

10. A method of operation of the hybrid power supply system with galvanic separation designed in particular for multipurpose machines according to claim 1, consisting in that the type of power supply to the multipurpose machine is selected at the workplace where operation with external power supply through a phase connector (105) and with a mounted traction battery (305) is provided, during which operation in a normal working cycle the traction battery (305) is recharged or, in the case of operation with 1 -phase power supply, additional energy is taken from the traction battery (305) in order to increase either the speed or power of the multipurpose machine based on the preferences of the manufacturer of the multipurpose machine, which are set by at least one electronic control unit ECU (600) by means of which the operation of subassemblies and the multipurpose machine are controlled.

11. The method according to claim 10, characterized in that the said traction battery (305) is charged during the working cycle of the multipurpose machine when powered from both 1 -phase and 3 -phase network or when connected to any other external power supply with which the multipurpose machine is powered, wherein the greater the difference between the power from AC/DC converters (200) and the electric motor (400), the greater power is redirected to charge the traction battery (305) when the electric motor (400) operates at full load.

12. The method according to claim 10 or 11, characterized in that the traction battery (305) is excited by an additional source of DC power supply in the form of a battery (830).

13. The method according to claim 10 or 11, characterized in that a converter (315) designed to control the electric motor (400) is used to convert direct current DC to alternating current AC with adjustable initial frequency thus ensuring a precise control of the input value for the electric motor (400).