Device and method for producing hybrid power

Abstract

The invention relates to a device (10) for producing hybrid electrical power, the device comprising photovoltaic panels (12) and at least one rotary machine generator (11) that is isochronous in response to an electrical load to be supplied, each generator comprising an alternator. The device further comprises: - a memory storing a limit value for the minimum electrical power to be supplied by each rotary machine generator; - a controller (15) configured to limit the electrical power supplied by the photovoltaic panels according to the electrical load to be supplied and to the stored limit value for the minimum electrical power to be supplied by the generators; and - a means for electrically coupling the alternator of each generator in operation. In certain embodiments, the device further comprises at least one electric battery (13) and the controller (15) is configured to limit the electrical power supplied by the photovoltaic panels (12) according to the electrical load to be supplied, the level of charge of each battery, the maximum charging current for each battery and the stored limit value for the minimum electrical power to be supplied by each generator (11).

Description

[0001] DEVICE AND METHOD FOR PRODUCING HYBRID ENERGY

[0002] TECHNICAL FIELD OF THE INVENTION

[0003] The present invention relates to a device and a method for producing hybrid electrical energy combining photovoltaic production and an isochronous rotating machine generator. It applies, in particular, to the field of electrical co-production systems using photovoltaic panels and generator sets.

[0004] STATE OF THE ART

[0005] 34.7% of businesses have diesel-powered generators (DPGs). Not surprisingly, power shortages correlate with businesses’ decision to purchase DPGs. As disruptions increase in frequency and duration, more businesses become DPG users. More than half of businesses in Sub-Saharan Africa use DPGs, and approximately 40% in the MENA (Middle East and North Africa) and South Asia regions. While these DPG systems are most likely used to supplement conventional power grids, they still account for 24–30% of the electricity consumed by businesses in these three regions. In South America, Central Asia, and Europe, distributed power systems account for less than 10% of business electricity consumption.

[0006] Today, fossil fuel generators are not compatible with photovoltaic systems in simultaneous production. Indeed, on a simple architecture, the photovoltaic panels inject a non-zero active load towards the generators, which therefore receive a negative load call that requires the generator electronics to be secured.

[0007] Furthermore, the power factor of a diesel generator is incompatible with that of a photovoltaic power plant. It is therefore necessary to use two separate transformers to connect them to the same electrical network.

[0008] Synchronous machine generator systems rely on energy production devices from thermal machines combined with a rotating machine. These systems cannot be combined with static energy generation devices such as photovoltaic panels without disrupting the proper functioning of the system.

[0009] Installing a solar power plant often requires months of design time and a few weeks of implementation. This design timeframe does not allow for the requirements of a rapidly deployable plant. This severely limits the project to temporary deployment with no established long-term visibility.

[0010] Coupling is, in fact, a concern for microgrid stability and load smoothing. The stator of a synchronous machine cannot be directly connected to a grid, because the currents would be too intense. To achieve optimal coupling of a synchronous machine, it is necessary to:

[0011] - drive it at a fixed speed and with an auxiliary motor;

[0012] - excite it to produce driving electromagnetic forces equal to the network voltages;

[0013] - couple it when the driving electromagnetic forces and the corresponding network voltages are in phase.

[0014] Existing systems are based on static coupling, meaning that any heat engine (or steam or hydraulic turbine) is equipped with a centrifugal regulator that acts on the intake of fuel into the cylinders (or steam or water on the turbine blades) in order to maintain a constant rotation speed. By its very principle, the regulator only modifies the position of the intake valve if there is a variation in the speed of the machine.

[0015] The principle of statism (with frequency variation) is used today by most manufacturers to limit the photovoltaic power produced, if necessary, depending on the call for the rotating machine generator set.

[0016] This approach often leads to temporal conflicts between the groups and the photovoltaic plant (linked to the weather or diurnal cyclicality).

[0017] It is also demanding for generator sets, as it requires rapid stops and restarts, leading to load calls that are not compatible with generator sets without gearboxes. Finally, power factor management generates a reactive load return to induction devices.

[0018] SUMMARY OF THE INVENTION

[0019] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0020] To this end, according to a first aspect, the present invention aims at a hybrid electrical energy production device according to claim 1.

[0021] Thanks to these provisions, it is possible to simultaneously implement at least one rotating machine generator and photovoltaic panels.

[0022] The invention is primarily applicable to the military field, life bases, mountain sites, isolated sites, island sites, field hospitals, but also to the civil field on emergency groups associated with a photovoltaic infrastructure (tertiary, residential, industrial).

[0023] Power supply to remote sites meets a growing need among industrial sites connected or disconnected from the grid, as well as on remote sites open to the public. The resilience of these installations is a key factor.

[0024] In embodiments, the coupling of each generator is an electromechanical physical coupling.

[0025] In embodiments, the controller is configured to regulate the cos phi of the photovoltaic panels based on the cos phi of the electrical load to be supplied.

[0026] This improves the operation of the device. In embodiments, to regulate the cos phi of the photovoltaic panels, on each of the phases, the controller regulates the phase shift of the voltage and the electrical intensity produced by the photovoltaic panels so that the cos phi of the electrical load is equal to the production cos phi in order to cancel the difference between the active power, respectively reactive, required by the electrical load and those produced by the assembly of at least one generator and by the photovoltaic panels.

[0027] In embodiments, the device further comprises at least one electric battery which comprises a set of cells connected in series, each cell comprising an energy storage element connected in series with a first switch and a shunt switch connected in parallel with the energy storage element and the first switch, power electronics controlling the switches of each cell in such a way that when the first switch is open, the shunt switch is closed and when the first switch is closed, the shunt switch is open, an ammeter measuring the electrical charging intensity between power supply terminals, the control electronics simultaneously controlling the switches of the battery to:

[0028] - if the measured intensity is greater than a predetermined maximum intensity, increase the number of energy storage elements connected in series by closing at least one first switch, and

[0029] - if the measured intensity is lower than a predetermined minimum intensity, reduce the number of energy storage elements connected in series by opening at least one first switch.

[0030] This protects each electrical energy storage element against overvoltages or undervoltages that are not optimal for their operation.

[0031] In embodiments, if the measured current is greater than a predetermined maximum current, the rate of increase in the number of series-connected energy storage elements is greater than one element per five millisecond time interval.

[0032] In embodiments, the rate of increase is an increasing function of the difference between the measured intensity and the predetermined maximum intensity.

[0033] In embodiments, the rate of reduction in the number of series-connected energy storage elements is greater than one element per five millisecond time interval.

[0034] In embodiments, the reduction rate is an increasing function of the difference between the predetermined minimum intensity and the measured intensity.

[0035] In embodiments, the battery comprises a coil connected in series with all of the battery cells between the power terminals.

[0036] In embodiments, the device further comprises at least one electric battery, in which the controller is configured to limit the electric power supplied by the photovoltaic panels as a function of the electric load to be supplied, the charge level of each battery, the maximum charging current of each battery and the stored limit value of minimum electric power to be supplied by each generator.

[0037] Thanks to these provisions, it is possible to simultaneously implement at least one rotating machine generator, photovoltaic panels and batteries.

[0038] In embodiments, the controller is configured to, when no generator is operating, limit the electrical power supplied by the photovoltaic panels based on the electrical load to be supplied, the charge level of each battery and the maximum charging current of each battery.

[0039] Thanks to these provisions, photovoltaic panels and batteries can be used simultaneously.

[0040] In embodiments, the controller is configured so that, when the photovoltaic panels are not providing electricity, each generator operates as an isochronous / isovoltage voltage generator and each inverter of each battery operates, in recharging or discharging, as a current generator.

[0041] Thanks to these provisions, at least one generator and batteries can be used simultaneously.

[0042] In embodiments, the controller is configured so that, in a so-called "ecological" configuration, each generator does not charge a battery and so that, once empty, it controls the recharging of each battery only in the event of surplus electricity supplied by the photovoltaic panels.

[0043] This reduces the consumption of fossil energy.

[0044] In embodiments, the controller is configured so that, in a so-called "reserve power" configuration, each battery is always charged to reach a predetermined level of reserve electrical energy storage.

[0045] This provides a reserve of safety electrical energy in the batteries.

[0046] In embodiments, the device comprises at least one container configured to transport at least one generator, at least one inverter, at least one battery and / or at least photovoltaic panels.

[0047] Thanks to these provisions, the transport of the device is facilitated.

[0048] In embodiments, at least one of the photovoltaic panels is treated to be anti-reflective and can operate over an area with glare restrictions.

[0049] In embodiments, at least one battery is equipped with an internal per-cell switching system to replace the function of the inverter.

[0050] In embodiments, the generator set is powered by a fuel such as diesel, jet fuel, ammonia, HMO, methanol, hydrogen, fuel oil, biomethane, biogas, or natural gas.

[0051] In embodiments, the generator set is equipped with a gearbox in addition to the alternator. In embodiments, at least one generator and / or at least photovoltaic panels are configured to produce electricity having a voltage less than or equal to one hundred and twenty volts and, preferably, eighty volts.

[0052] This reduces the risk of electrocution for fitters and / or operators.

[0053] According to a second aspect, the present invention relates to a method for producing hybrid electrical energy with photovoltaic panels and at least one isochronous rotating machine generator in response to an electrical load to be supplied, which comprises:

[0054] - a step of reading, in memory, a minimum electrical power limit value to be supplied by each rotating machine generator and

[0055] - a step of limiting the electrical power supplied by the photovoltaic panels according to the electrical load to be supplied and the limit value read for the minimum electrical power to be supplied by the generators.

[0056] BRIEF DESCRIPTION OF THE FIGURES

[0057] Other advantages, aims and particular characteristics of the invention will emerge from the following non-limiting description of at least one particular embodiment of the method and device which are the subject of the present invention, with reference to the appended drawings, in which:

[0058] Figure 1 is a block diagram of a device which is the subject of the invention,

[0059] Figure 2 represents the constitution of a first container in a particular embodiment of the device which is the subject of the invention,

[0060] Figure 3 represents the constitution of a second container in a particular embodiment of the device which is the subject of the invention,

[0061] Figure 4 represents, in top view, a typical installation implementing the device which is the subject of the present invention,

[0062] Figure 5 represents a vector graph of series coupling of two alternators,

[0063] Figure 6 shows a dog clutch illustrating the coupling conditions,

[0064] Figures 7a, 7b, 8a and 8b schematically represent phase shift determination systems, and

[0065] Figure 9 represents the principle of a synchronoscope.

[0066] DETAILED DESCRIPTION

[0067] This description is given without limitation, each characteristic of an embodiment being able to be combined with any other characteristic of any other embodiment in an advantageous manner. It should be noted from now on that the figures are not to scale.

[0068] As understood from the present description, various inventive concepts may be implemented by one or more methods or devices described below, several examples of which are provided herein. The actions or steps performed in carrying out the method or device may be ordered in any suitable manner. Accordingly, it is possible to construct embodiments in which the actions or steps are

[0069] CORRECTED SHEET (RULE 91) ISA / EP performed in a different order than illustrated, which may include performing certain acts simultaneously, even if they are shown as sequential acts in the illustrated embodiments.

[0070] The expression "and / or", as used herein, shall be understood to mean "either or both" of the elements so conjoined, i.e., elements which are present conjunctively in some cases and disjunctively in other cases. Multiple elements listed with "and / or" shall be interpreted in the same way, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present, other than the elements specifically identified by the "and / or" clause, whether or not they are related to those specifically identified elements.Thus, by way of non-limiting example, a reference to "A and / or B", when used in conjunction with open language such as "comprising" may refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0071] As used herein, the term "at least one," in reference to a list of one or more elements, is to be understood to mean at least one element selected from one or more elements in the list of elements, but not necessarily including at least one of each element specifically listed in the list of elements and not excluding any combination of elements in the list of elements. This definition also allows for the optional presence of elements other than the specifically identified elements in the list of elements to which the term "at least one" refers, whether or not related to those specifically identified elements.Thus, by way of non-limiting example, "at least one of A and B" (or, equivalently, "at least one of A or B", or, equivalently, "at least one of A and / or B") may refer, in one embodiment, to at least one, optionally including more than one, A, without B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, without A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0072] In the description below, all transitional expressions such as "comprising", "including", "bearing", "having", "containing", "involving", "holding", "consisting of", and the like, are to be understood as open, i.e., as meaning including, but not limited to. Only the transitional expressions "consisting of" and "consisting essentially of" are to be understood as closed or semi-closed transitional expressions, respectively.

[0073] Please note, from now on, that the figures are not to scale.

[0074] The operating mode of a hybrid power plant in modular containers, for deployment in the field of operation, is described below. An example of a typical configuration of a hybrid power plant 10 illustrated in Figure 1 includes the following energy sources:

[0075] - 11 Diesel electric generators which can, for example, go up to 32 generators of equal or different powers,

[0076] - 12 photovoltaic panels and inverters, for example in packs of 24 KWp, thus providing a partial supply of energy by the photovoltaic panels in the event of failure of one or more packs, and

[0077] - batteries and battery inverters 13.

[0078] Typically, on a sunny day, 75% of the electrical energy is generated by photovoltaic power, 15% by batteries, and 10% by a generator. At night, for example, the electrical energy is split equally between the batteries and the generator. On a cloudy day, the generator provides 75% of the electrical energy, with the remainder being split between photovoltaic power and batteries. Finally, in silent mode, the electrical energy is split equally between photovoltaic power and batteries.

[0079] With the three energy sources, generator set (or "generator") 11, photovoltaic ("PV") 12 and batteries 13, there are the following seven operating combinations ("0" means "not operating" and "1" means "operating"):

[0080] Operating mode PV generator(s) Battery(s)

[0081] Mode 1 “Silence” 0 0 1

[0082] Mode 2 “Ecological” 0 1 0

[0083] Mode 3 “Economy +” 0 1 1

[0084] Mode 4 “Thermal Energy” 1 0 0

[0085] Mode 5 “Redundancy” 1 0 1

[0086] Mode 6 “Economy” 1 1 0

[0087] Mode 7 “Hybrid” 1 1 1

[0088] These seven operating modes are detailed below.

[0089] Mode 1:

[0090] The battery inverter(s) operate as a three-phase isochronous / isovoltage voltage generator.

[0091] Mode 2:

[0092] It is impossible to operate photovoltaic panels without an electric generator and batteries. In the case of full batteries, the photovoltaic panels may be the only ones supplying energy to the load, but it is the battery inverter that provides the voltage / frequency reference, which amounts to the third operating mode.

[0093] Mode 3:

[0094] The battery inverter(s) operate as a three-phase isochronous / isovoltage voltage generator. The device's controllers limit the electrical power supplied by the photovoltaic panels according to the load to be supplied, the battery charge level and the maximum battery charging current.

[0095] The inverter controllers are programmed to accumulate the energy produced by the photovoltaic panels and deliver, depending on the power required by the use (i.e. the electrical load), a three-phase signal to meet the power demand. This power is supplied to the network and to the battery as long as Pphotovoitaïque > Puse- The residual power (Pphoto oitaique - Puse) is used to recharge the battery as long as the battery is not charged and if the residual power does not exceed the maximum charging intensity (l ma x) of the battery multiplied by its effective voltage (U e ff).

[0096] The system constantly controls the amount of residual power to make it tend towards zero in order to avoid a power return.

[0097] To do this, the controllers control the system frequency and increase it in order to derate the power of the solar inverters (Pphoto electricity + P batteries = Puse).

[0098] It should be noted that derating in the case of a hybrid power plant is synonymous with a reduction in power or degradation of voluntary solar power.

[0099] The purpose of derating is to protect the electrical generator by preventing a transfer of power from the inverters of the photovoltaic power plant to the electrical generator in order to avoid a "power return" to the alternator of the electrical generator, which would cause a shutdown of this electrical generator.

[0100] This reduction in power is requested by an automaton by derating the nominal frequency of the network at 50.00 Hz to a higher frequency, such as 50.40 Hz, which has the consequence of reducing solar production.

[0101] In this embodiment, the quantity of batteries is deliberately limited to be used only as a buffer. The main power contributors are the generator and the photovoltaic panels except for transients between the two (power drop or power recovery of the photovoltaic panels and generator reaction time). This limited quantity of batteries allows for a lower installation price.

[0102] Mode 4:

[0103] The electric generator(s) operate as a three-phase isochronous / isovoltage generator, using known techniques.

[0104] Mode 5:

[0105] The electric generator(s) operate as a three-phase isochronous / isovoltage voltage generator and the battery inverter operates as a current generator (recharge or discharge).

[0106] In this mode, two configurations are possible:

[0107] - an “ecological” configuration: the generators never charge the batteries and, once empty, the batteries wait for the presence of surplus sun to be recharged and

[0108] - a “Reserve Power” configuration: the batteries are always charged to reach a reserve energy stock level. Mode 6:

[0109] The electrical generator(s) operate as a three-phase isochronous / isovoltage generator. The device's controllers limit the electrical power supplied by the photovoltaic panels according to the load and the minimum power threshold desired on the generators.

[0110] Thus, on each of the phases in relation to the neutral, the voltage generated by the generator delivers a power PGE and the photovoltaic panels a Power Ppv. If P Uitself <PcE +Ppv alors le contrôleur, via l’onduleur, fait baisser artificiellement la puissance des panneaux photovoltaïque Ppv d’un facteur de détarage a pour que P US e=PGE + a PPV.

[0111] Power derating is controlled by the network frequency.

[0112] The Fronius inverter has a power derating mode based on the network frequency called "EXT limit" which is controlled by the controller.

[0113] The parameters used are as follows: Linear derating rate (a) at 165%. The frequency of 50.00 Hz is equal to a 100% power limitation, i.e. all available solar power. The frequency of 50.80 Hz is equal to a 0% power limitation, i.e. no power produced (despite the presence of solar radiation). The frequency of 51.00 Hz is interpreted as an order to disconnect by the inverter.

[0114] The controllers also regulate the cos phi of the photovoltaic panels according to the cos phi of the load. On each phase, the controllers regulate the phase shift of the voltage and current so that the Cos <p use is equal to Cos <p de production afin d’annuler la différence entre la puissance active (resp. réactive) demandée par l’usage et celles produites par le générateur et la production photovoltaïque.

[0115] By default an inverter is composed of static power electronic elements and will tend to produce perfect networks at a Cos <p = 1 , ce qui laisserait la totalité de l’énergie réactive à absorber par l’alternateur du générateur 11. Cela représente plus de courant dans les câbles électriques, soit plus de pertes.

[0116] Photovoltaic (“PV”) inverters 12 are controlled in such a way as to degrade their Cos <p pour le partager avec les générateurs électriques (« GE ») (Cos <p GE = Cos <p PV). La limite basse des onduleurs Fronius est fixée par le constructeur à Cos <p = 0,8. Le système d’automates permet de piloter le Cos <p des onduleurs PV (Fronius) par l’intermédiaire d’une communication en Modbus (marque déposée) sous un protocole SunSpeac (marque déposée) afin de piloter la répartition de puissance réactive (Q en kVAR) en temps réel.

[0117] We recall here that the cos phi or cos <p est le cosinus de l'angle entre la tension et le courant. On le calcule en effectuant la division de la puissance réelle (en Watt) par la puissance apparente (en VA). Il est compris entre zéro et un. Ainsi, la puissance réelle ne peut pas être supérieure à la puissance apparente.

[0118] In alternating current circuits, there are three types of receivers: resistors, inductors, and capacitors. However, only the resistor will actually develop active power. On average, a pure inductor (a motor winding) or a pure capacitor consumes nothing from the network.

[0119] When an installation draws 10 amps from the network, only the component in this current that is in phase with the voltage, which acts in synchronism with the network, should be considered: this is called the active component or active current. It is this current that will develop power, also called “active” power. From there, the formula for AC power:

[0120] Power = Voltage x Active Current

[0121] And

[0122] P = U x I x Cos phi where “phi” is the phase shift of the current with respect to the voltage.

[0123] Reactive power Q is defined by analogy to active power P:

[0124] Q = U x I x Sin phi

[0125] It is expressed in VAr or VAR, an abbreviation of “volt-ampere-reactive”.

[0126] Its interest comes from the fact that it allows the importance of inductive receivers (motors, fluorescent lamps) and capacitive receivers (capacitors) in the installation to be assessed.

[0127] The controller also controls the cos phi of the photovoltaic panel inverters, thus maintaining a cos phi on the generator sets that complies with the alternator manufacturer's specifications. This control function prevents the alternators from being stressed by exposing them to reactive loads, which can lead to material damage to the alternator and potentially to the motor that drives it.

[0128] It is recalled here that, to protect the alternator against damage of electrical or mechanical origin and also to protect the Diesel engine (If the machine which drives the alternator is a turbine, the electrical safety devices are the same, there are only differences at the level of mechanical safety devices) which drives it, the coupling circuit breaker is open in the event of:

[0129] 1. protections connected to voltage transformers:

[0130] - lack of tension (0.75 x Nominal Ll for 3 s => general stop);

[0131] - overvoltage (1, 1 x Unominaie for 2 s => general shutdown);

[0132] - maximum frequency (1, 05 x Nominal F for 2 s => general stop) and minimum frequency (0.95 x Nominal F for 2 s => general stop);

[0133] - synchronization control: prevent closing during synchronization if: frequency < ±1 Hz, voltage < ±5%, phase < 10°;

[0134] 2. protections connected to the current transformers on the line side:

[0135] - active power return relay (This is to prevent the synchronous machine from operating as a motor and driving the Diesel or the turbine, which would consume active power on the network and could also lead to serious mechanical incidents such as coupling or even shaft breakages at the Diesel or alternator level), (1 -5% if turbine, 5-20% if Diesel, for 2 s => general shutdown);

[0136] - maximum current, (1.5 x In for 2 s => general shutdown); - alternator differential protection which ensures that the vector sum of the currents is substantially the zero vector (for groups > 2 MV A).

[0137] 3. general mechanical protections of the group connected to detectors:

[0138] - stator temperature (recommended for alternators above 2 MV A);

[0139] - bearing temperature (recommended for alternators above 8 MV A);

[0140] - rotor earth protection.

[0141] 4. mechanical protections linked to the alternator drive diesel:

[0142] - insufficient lubricating oil pressure;

[0143] - exhaust temperatures too high;

[0144] - bearing temperature too high;

[0145] - overspeed.

[0146] Mode 7:

[0147] The electrical generator(s) operate as a three-phase isochronous / isovoltage generator. The device's controllers limit the electrical power supplied by the photovoltaic panels according to the load, the battery charge level, the maximum battery charge current and the minimum power threshold desired on the generators.

[0148] The power of PGE electric generators is set at a minimum, for example 5 or 10% of their nominal power, to avoid underutilization of the motors for too long and therefore premature aging. On this basis, the power of the PV inverters is adjusted according to the power of the load or use: P USe = PGE + Pbattery + a PPV. The whole is controlled by a CANbus controller device (registered trademark) which allows a response (load distribution) to the millisecond and therefore at a frequency of 1 kHz, i.e. 15 to 20 times the network frequency.

[0149] It should be noted here that the power distribution is controlled by CANbus communication (registered trademark). The orders sent by the controllers to the Fronius inverters (registered trademark) and to the BAT inverters are sent in Modbus (registered trademark) under the SunSpeac protocol (registered trademark).

[0150] Regulation of the cos phi of the photovoltaic panels according to the cos phi of the load. The battery inverter operates as a current generator (recharge or discharge).

[0151] The device 10 therefore comprises three power regulation devices: a photovoltaic regulation module 16 which controls the solar inverters, a battery regulation module 17 which controls the battery inverters and a module 18 for regulating the electric generators which control the generator sets, jointly constituting a controller 15. There is also a human-machine interface (“HMI”) module (not shown) for supervision, for example on a touch screen.

[0152] The photovoltaic regulation module 16 has the following functions:

[0153] - communication with the photovoltaic panel inverter via SunSpec protocol in plug & play (registered trademarks) - module 16 has master read and write functions; - local display of electrical parameters;

[0154] - time-stamped recordings and display of alarms and faults;

[0155] - control of the inverter of the photovoltaic panels including:

[0156] - internal disconnection control (if load disconnection and power return to electric generators, for example),

[0157] - control of the maximum power supplied by the photovoltaic panels, and

[0158] - control of the Cos Phi of photovoltaic panels;

[0159] - the battery regulation module 17 has the following functions:

[0160] - communication with the three single-phase inverters via Modbus TCP protocol (registered trademark). Module 17 has master read and write functions,

[0161] - local display of three-phase electrical parameters,

[0162] - time-stamped recordings and display of alarms and faults,

[0163] - the adjustment and management of minimum and maximum thresholds for charging and discharging batteries depending on the type of batteries (e.g. 100% to 20% for Lithium batteries and 100% to 50% for GEL batteries);

[0164] - control of the three battery inverters:

[0165] - control of internal disjunction,

[0166] - control of the direction of the current (recharge or discharge),

[0167] - control in “ecological” mode: only excess sunlight recharges the batteries - in case of lack of sunlight, the batteries provide the missing energy,

[0168] - control in “power reserve” mode: Below the power reserve limit / threshold, the batteries are recharged with all available energy - above this power reserve limit / threshold, the operating mode is ecological mode;

[0169] - the maximum battery current limit / threshold that can trigger (if configured) the start of the electric generator;

[0170] - a control module 19 has the following functions:

[0171] - the management of all energy sources with controllers (not shown on each source, communicating with each other via CANbus (registered trademark) 37 (see figure 3) during exchanges of a few microseconds, and thus offering reaction times, stability performances, and precision performances, which an EMS system communicating via Modbus (registered trademark), close to the second, with all energy sources, cannot offer and

[0172] - the management of a power plant with several generators and / or tie-breakers and / or network, associated with renewable energy sources, and arbitrating all sources with the same system.

[0173] It is noted that the use of sodium ion or gel batteries can reduce the risk of thermal runaway and lithium fire.

[0174] On isolated sites, the electrical power plant is equipped with several alternators rather than a single one whose power would be sufficient to supply the entire site. This choice makes it possible to: - limit the effects caused by the failure of an alternator (a single faulty alternator would deprive the ship of all electrical power) and to reduce the power of the emergency machine to be provided;

[0175] - to distribute the power requested by the ship between several alternators operating close to their nominal powers and therefore close to maximum efficiency;

[0176] - to limit the problems of realization and operation of alternators.

[0177] However, the parallel operation of several alternators poses two problems:

[0178] - voltage regulation of each alternator;

[0179] - the frequency regulation of each machine and therefore the speed regulation of the machine which drives the alternator.

[0180] The first problem is solved by parallel operation, each alternator being imposed the voltage of the network to which it is coupled. Since regulating the voltage of the network thus constituted becomes an overall problem, action is taken on all the machines in the network and not just one of them.

[0181] The same applies to the problem of frequency regulation: an alternator connected to a network has its frequency, and therefore its rotation speed, imposed by the network, unless it is capable of driving all the other alternators on the network at the frequency it would impose. Frequency regulation must be resolved at the level of all the machines.

[0182] Commissioning an alternator solves the following problems:

[0183] - coupling the alternator to the network;

[0184] - distribution of power between this machine and the network (distribution of active and reactive power between two alternators in parallel);

[0185] - optimal distribution of power; and

[0186] - stability of alternator operation.

[0187] Series coupling is not used because it leads to unstable operation. Indeed, the vector graph of the electromotive forces (taking the current common to two alternators as the origin of the phases) would be that of figure 5. If alternator n°1 took a lead, the angle would become larger. The electromagnetic power Ei / cos^ / i of this alternator would become weaker and it would oppose to the diesel or the turbine which drives it a weaker resistive torque, causing a new increase in speed. The series operation is therefore unstable, and consequently unusable Except in the very rare case of two mechanically coupled alternators (angels and ^2 are then linked together). The series coupling would be used to obtain high voltages but this is what the static transformer allows. The prerequisites for the physical electromechanical coupling of the alternators are stated below.We first use a mechanical analogy to understand the need for coupling: the dog clutch (see figure 6), widely used in gearboxes. For the mechanical connection to be established, the male splines must fit into the female splines. To do this, the speed difference between the two discs carrying the splines must be very small, otherwise each part with splines - whether male or female - behaves like a uniform solid disc with respect to the other, and the clutch is impossible. Even if the speed difference is sufficiently small, the clutch will only be possible if each part is in phase with the other, that is to say if the male splines are directly opposite the female splines. We understand that if the male (respectively female) splines of one disc are directly opposite the male (respectively female) splines of the other disc, the clutch will also be impossible.

[0188] This mechanical analogy shows the necessity:

[0189] - that the two axes have very close speeds; and

[0190] - that their phase shift is almost zero.

[0191] The stator field and rotor field can be likened to the two discs carrying the grooves of a dog clutch. For these two fields to couple, their relative speed must be low and they must be roughly in phase.

[0192] Let us consider a generator G supplying into any external network. Let U be the voltage between the coupling terminals. Let us denote by E the electromotive force of the generator G, by Z its internal impedance. Depending on whether this electromotive force E is greater or less than U at the moment when the coupling switch is closed, the machine G operates as a generator or a receiver and is traversed by a current I given by the relation:

[0193] Since the impedance Z of the generator G is generally very low, the current I can take, for a fairly small difference between E and U, a fairly large value and this suddenly at the moment when the coupling circuit breaker is closed.

[0194] This current determines a sudden resistive torque (E > U) or a sudden motor torque (E < U). In both cases, the group undergoes a jerk that is detrimental to its good mechanical performance. This is why, when a generator is coupled to terminals AB (in parallel with others), its electromotive force E (voltage between terminals at no-load) is first given a value equal to the voltage U between A and B.

[0195] In alternating current, the voltages and electromotive forces are periodic. The above conditions must be met at all times during their periods. In other words, the electromotive force curve e(t) of the alternator to be coupled must be superimposed on the voltage curve u(t) between the bars of which the other alternators are already connected. However, for two sinusoids to be superimposed, it is necessary:

[0196] - the same order of succession of phases; - the equality of their maximum values, therefore of their effective values;

[0197] - the equality of their frequencies; and

[0198] - equality of phases (zero phase shift between them).

[0199] The device in Figure 7 makes it possible to verify that these conditions are met. The same order of phase succession results in "flickering lights", equality of frequencies and phases in the permanent extinction of the lamps. However, it is preferable to check the equality of voltages using the voltmeter located on the coupling panel. In practice, the frequency of the alternator to be coupled is set to a value slightly higher than that of the network. The lamps will flash slowly, all passing together through phases of maximum brightness (phase opposition) and extinction. If an extinction phase lasts about 3 seconds, the frequencies will be close enough to consider coupling. The middle of an extinction phase (zero phase shift) is estimated and the coupling order is given at this instant.

[0200] Figure 7(a) shows the coupling with beating lights. Figure 7(b) shows the coupling with rotating lights.

[0201] The coupling accuracy can be improved by using device (b) in Figure 8 where the lights are said to be "rotating". The coupling is controlled at the extinction of Li and at the equality of brightness of Z.2 and L,. This can be appreciated more finely than the middle of the extinction phase of the lamps connected to swinging lights. Figure 8(a) represents the coupling with swinging lights. Figure 8(b) represents the coupling with rotating lights.

[0202] For increased accuracy, it is advisable to use a synchronoscope when present on the coupling panel. This is a small single-phase asynchronous motor powered by one phase of the network and by the corresponding phase of the alternator to be coupled. The motor has a two-phase auxiliary phase as shown in Figure 9. It is stopped when the frequencies are equal and it indicates the sign of the frequency difference by its direction of rotation (alternator to be coupled with a frequency higher than that of the network if the rotation is clockwise). The faster the synchronoscope needle turns, the greater the frequency difference. In practice, the synchronoscope needle must turn sufficiently slowly (one turn in 4 or 5 seconds minimum). The order to close the coupling circuit breaker is given around "five to twelve or ten to twelve" depending on the size of the coupling circuit breaker and therefore the time taken by the poles to close.

[0203] In variants of the device, a gearbox generator set is used in conjunction with fixed-speed generator sets. The electromagnetic coupling of the generators is then fixed to the fixed frequency.

[0204] The device preferably combines a coupling to an electrochemical battery with an inverter allowing the replacement of battery and inverter devices.

[0205] The battery comprises a set of cells connected in series. This battery has dedicated power electronics allowing it to perform cell status diagnostics and also allowing the power delivered by it to be varied by being self-switched in the following manner. Each cell comprises an energy storage element connected in series with a first switch. Each cell also comprises a shunt switch connected in parallel with the assembly composed of the energy storage element and the first switch. The power electronics comprises a controller which controls the switches of each cell in such a way that, in each cell when the first switch is open, the shunt switch is closed and when the first switch is closed, the shunt switch is open. An ammeter measures the electrical load intensity between the power supply terminals.The controller simultaneously controls the battery switches to:.

[0206] - if the measured intensity is higher than a predetermined maximum intensity, increase the number of energy storage elements connected in series by closing at least one first switch (and therefore opening the shunt switch of the same cell), and

[0207] - if the measured intensity is lower than a predetermined minimum intensity, reduce the number of energy storage elements connected in series by opening at least one first switch (and therefore closing the shunt switch of the same cell).

[0208] Preferably, if the measured intensity is greater than a predetermined maximum intensity, the rate of increase in the number of energy storage elements connected in series is greater than one element per five millisecond time interval and preferably one element per millisecond. For example, this rate is an increasing function of the difference between the measured intensity and the predetermined maximum intensity.

[0209] Preferably, the rate of reduction of the number of energy storage elements connected in series is greater than one element per five millisecond time interval and preferably one element per millisecond. For example, this rate is an increasing function of the difference between the predetermined minimum intensity and the measured intensity.

[0210] Preferably, to limit the speed of evolution of the electric charging current, a coil is connected in series with all the cells of the battery between the power supply terminals.

[0211] The advantages of the invention include:

[0212] - improved low voltage or high voltage network stability,

[0213] - a reduction in the reactive load on the distribution or transport network,

[0214] - a reduction in diesel consumption,

[0215] - a reduction in the aging of the diesel group, because the latter is less stressed and less impacted by calls for active or reactive loads,

[0216] - a reduction in the discharge factor of a battery,

[0217] - a safer and more resilient energy production architecture,

[0218] - reduced deployment and withdrawal time and

[0219] - a reduced preliminary study period.

[0220] In variants, at least one of the photovoltaic panels 12 is treated to be anti-reflective and can operate in an area with glare restrictions. In variants, at least one battery 13 is equipped with an internal switching system per cell allowing the inverter function to be replaced. In variants, the generator 11 is powered with a fuel such as diesel, jet fuel, ammonia, HMO, methanol, hydrogen, fuel oil, biomethane, biogas, or natural gas. In variants, the generator 11 is equipped with a gearbox in addition to the alternator. The use of a gearbox also makes it possible to do without large-capacity battery storage.

[0221] An example of an embodiment of the device is given below:

[0222] - 216 340 Wc EURENER modules (registered trademark),

[0223] - anti-reflective treatment applied in the factory by the manufacturer: luminance < 20,000 cd / m 2 suitable for airport areas,

[0224] - 60 cell modules 1700 mm x 1000 mm x 40 mm - 19 kg,

[0225] - 18 fuse cards and 18 DC / DC converters to ensure the implementation of TBTS (very low safety voltage <120 V, or even <80 V), and

[0226] - optionally, IP68 boxes for protection of the TBTS system.

[0227] One of the objectives of the invention is to protect the technician or soldier who will be assembling and dismantling the installation by only handling low continuous voltages below 120 V or 80 V. The technician will therefore not have to have specific high continuous voltage electrical authorization.

[0228] The modules are connected in groups of two to form four “strings” (four “+” and four “-”) to remain at a voltage lower than 120 V or 80 V.

[0229] A voltage lower than 120 V, and even lower than 80 V, limits the risk of electrocution, particularly in busy areas.

[0230] Next, the modules are connected in parallel and each string of modules is monitored. Then, the voltage is increased to match the inverter's voltage range.

[0231] The inverter reinjects into the charge / discharge busbar, in three-phase.

[0232] As illustrated in figure 2, an example of a first container 20 dedicated to photovoltaic panels comprises the photovoltaic modules 21, electric cables 22, for example 4 mm 2 of cross-sectional area, and optional fuse cards 23 for connecting five lines of two modules in series per fuse card 23.

[0233] As illustrated in Figure 3, an example of a second air-conditioned container 30 is dedicated to the TBTS (very low safety voltage) 31, to the alternating current protections 32, to the photovoltaic panel inverters 33, to the inverters / battery chargers 34, to the modules 16 and 17, to the batteries 13, and to a supervisor 35.

[0234] The generator(s) 11 are not in the containers 20 and 30. However, this or these generator(s) 11 and the photovoltaic modules 12, once deployed, are connected to the battery container 30 by double-insulated extension cables. MC4 multi-contact connectors (registered trademark) certified for photovoltaic use are used.

[0235] The hybrid power plant is thus preferably composed of the following energy sources:

[0236] - Diesel generators with up to 32 generators of equal or different power,

[0237] - photovoltaic panels and inverters in packs of 24 KWp thus providing a partial supply of photovoltaic energy in the event of failure of one or more packs - in practice, during implementation, the inverters are Fronius Symo 20 (registered trademark) of 20 kW maximum (19.4 kW actual with their yield). However, they are connected to six TBTS transformers themselves connected to six strings of two 340 Wp panels and

[0238] - batteries and battery inverters in packs of 45 KVA over 20 minutes (i.e. 15 KVAh) thus providing a partial supply of battery energy in the event of failure of one or more packs.

[0239] Each three-phase battery pack is composed of two 15 KVA inverters per phase, or six inverters. In practice, the inverters / chargers can be Victrons Quattro 15000 (registered trademarks). The battery is not separated into 15 KVAh elements but is a single unit. It is composed of 24 2 V batteries of 1,800 Ah or 86,400 kWh.

[0240] This device also allows to deliver by a connection detection system on the sockets (type A to N socket defined by the IEC TR 60083 standard, but also USB A, BC, micro) associated with a direct voltage and / or an alternating voltage with associated frequency and voltage, typically with direct voltages of 3V, 5V, 9V, 12V, 24V or 48V and variable voltages with frequency of 50 or 60Hz and 110, 230 or 400V in low voltage. Other voltages are applicable for medium voltage or high voltage networks, but are not detailed here. The management of active loads and reactive loads is then carried out by this device.

[0241] In variants of the device which is the subject of the invention, a multiple or continuous variation gearbox (for example toroidal) is used, or a flywheel gearbox making it possible to do without a load bank or a regulating battery charging system.

[0242] This device allows the engine to operate in its optimal operating range, reducing consumption.

[0243] In variants of the device which is the subject of the invention, this device is mounted on a trailer or a carrier making it mobile.

[0244] In variants of the device which is the subject of the invention, the generator sets are hybrid road or non-road vehicle engines.

[0245] In variants of the device that is the subject of the invention, the solar power sources are flat or flexible photovoltaic panels of the CIGS or perovskite silicon type or systems with 3D geometry (vertical bifacial solar, 3D configuration of the Tipa PV type)

[0246] In variants of the device which is the subject of the invention, the fatal heat from the generator sets, batteries and / or inverters is reused for third-party uses (heating, domestic hot water, distillation, cold, heat pump)

[0247] In variants of the device that is the subject of the invention, energy sources may include wind, hydraulic, fuel cells or thermovoltaics.

[0248] The invention covers the needs of coupling rotating machinery and photovoltaic panel fields. The containerizable and easily deployable aspect makes it possible to cover the needs of living bases (military, "Oil and gas", or oil and gas, mining, non-governmental organizations, humanitarian camps), isolated sites, islands, isolated industrialists or those wishing to use the photovoltaic network and emergency diesel or turbine generators. The expected results are, on the one hand, savings thanks to the reduction in fuel consumption of diesel generators of around 30% in the deployed configuration (the savings can be greater by adding solar production).

[0249] On the other hand, savings in generator maintenance costs, thanks to the reduction in the number of operating hours consumed per day made possible by stopping the generators when solar production and the state of charge of the batteries allow it.

[0250] This saving is around 15 to 20% of the time depending on the season.

[0251] The invention makes it possible to solve the problem of coupling a diesel generator set, which is a rotating machine, with a photovoltaic architecture based on static inverters on the basis of an existing automaton.

[0252] The invention prevents premature wear of the electric generator by operating it at too low a load or avoiding repeated cold starts. A minimum setpoint (modifiable by the user) of around 10% is therefore imposed on the electric generator. In situations where the electric generator is operating, the device sometimes restricts solar production in order to guarantee the electric generator a minimum load while the solar resource is present. It should be noted that a momentary drop in solar production linked to the weather can cause the electric generator to start.

Claims

CLAIMS 1. Device (10) for producing hybrid electrical energy comprising photovoltaic panels (12) and at least two generators (11) with isochronous rotating machine in response to an electrical load to be supplied, each generator comprising an alternator, characterized in that it further comprises: - a memory retaining a minimum electrical power limit value to be supplied by each rotating machine generator, - a controller (15) configured to limit the electrical power supplied by the photovoltaic panels as a function of the electrical load to be supplied and the stored limit value of minimum electrical power to be supplied by the generators, and - a means of electrically coupling the alternator of each generator in operation.

2. Device (10) according to claim 1, wherein the coupling of each generator is an electromechanical physical coupling.

3. Device (10) according to one of claims 1 or 2, in which the controller (15) is configured to regulate the cos phi of the photovoltaic panels (12) as a function of the cos phi of the electrical load to be supplied.

4. Device (10) according to claim 3, in which, to regulate the cos phi of the photovoltaic panels (12), on each of the phases, the controller (15) regulates the phase shift of the voltage and the electrical intensity produced by the photovoltaic panels (12) so that the cos phi of the electrical load is equal to the cos phi of production in order to cancel the difference between the active power, respectively reactive, required by the electrical load and those produced by the assembly of at least one generator (11) and by the photovoltaic panels (12).

5. Device (10) according to one of claims 1 to 4, which further comprises at least one electric battery (13) which comprises a set of cells connected in series, each cell comprising an energy storage element connected in series with a first switch and a shunt switch connected in parallel with the energy storage element and the first switch, power electronics controlling the switches of each cell in such a way that when the first switch is open, the shunt switch is closed and when the first switch is closed, the shunt switch is open, an ammeter measuring the electrical charging intensity between supply terminals, the control electronics simultaneously controlling the switches of the battery to: - if the measured intensity is greater than a predetermined maximum intensity, increase the number of energy storage elements connected in series by closing at least one first switch, and - if the measured intensity is lower than a predetermined minimum intensity, reduce the number of energy storage elements connected in series by opening at least one first switch.

6. Device (10) according to claim 5, wherein, if the measured intensity is greater than a predetermined maximum intensity, the rate of increase in the number of energy storage elements connected in series is greater than one element per time interval of five milliseconds.

7. Device (10) according to claim 6, in which the rate of increase is an increasing function of the difference between the measured intensity and the predetermined maximum intensity.

8. Device (10) according to one of claims 5 to 7, in which the rate of reduction of the number of energy storage elements connected in series is greater than one element per time interval of five milliseconds.

9. Device (10) according to claim 8, in which the reduction rate is an increasing function of the difference between the predetermined minimum intensity and the measured intensity.

10. Device (10) according to one of claims 5 to 9, in which the battery comprises a coil connected in series with all of the cells of the battery between the power supply terminals.

11. Device (10) according to one of claims 1 to 10, which comprises at least one electric battery (13), in which the controller (15) is configured to limit the electric power supplied by the photovoltaic panels (12) as a function of the electric charge to be supplied, the charge level of each battery, the maximum charge current of each battery and the stored limit value of minimum electric power to be supplied by each generator (11).

12. Device (10) according to claim 11, in which the controller (15) is configured to, when no generator (11) is operating, limit the electrical power supplied by the photovoltaic panels (12) as a function of the electrical load to be supplied, the charge level of each battery (13) and the maximum charging current of each battery.

13. Device (10) according to one of claims 11 or 12, in which the controller (15) is configured so that, when the photovoltaic panels (12) do not supply electricity, each generator (11) operates as an isochronous / isovoltage voltage generator and each inverter of each battery (13) operates, when recharging or discharging, as a current generator.

14. Device (10) according to claim 13, in which the controller (15) is configured so that, in the so-called "ecological" configuration, each generator (11) does not charge at least one battery (13) and so that, once empty, it controls the recharging of at least one battery only in the event of surplus electricity supplied by the photovoltaic panels (12).

15. Device (10) according to one of claims 13 and 14, in which the controller (15) is configured so that, in the so-called “reserve power” configuration, each battery (13) is always charged to reach a predetermined level of reserve electrical energy storage.

16. Device (10) according to one of claims 1 to 15, in which the controller (15) comprises a photovoltaic regulation module (16), which has the following functions: - communication with an inverter of the photovoltaic panels (12); and - control of the photovoltaic panel inverter: - internal disconnection control, for example, if there is load disconnection and power return on at least one generator (11), - control of the maximum power supplied by the photovoltaic panels and - control of the cos phi of photovoltaic panels.

17. Device (10) according to one of claims 11 to 15 or according to claim 16 when it depends on claim 11, in which the controller (15) comprises a module (17) for regulating each battery (13), which has the following functions: - communication with each single-phase battery inverter; - adjustment and management of minimum and maximum battery charge and discharge thresholds depending on the battery type; - control of each battery inverter: - control of internal disjunction, - control of the direction of the current, when recharging or discharging, - control in “ecological” mode: only the surplus of sun recharges at least one battery and in case of lack of sun, at least one battery provides the missing energy, and - control in “power reserve” mode: below the power reserve limit / threshold, at least one battery is recharged with all available energy; - reaching the maximum current limit value of each battery triggering the start of the electric generator.

18. Device (10) according to one of claims 1 to 17, which comprises at least one container (30) configured to transport at least one generator (11), at least one inverter, at least one battery and / or at least photovoltaic panels (12).

19. Device (10) according to one of claims 1 to 18, wherein at least one of the photovoltaic panels (12) is treated to be anti-reflective and can operate over an area with glare restrictions.

20. Device (10) according to one of claims 1 to 19, in which at least one battery (13) is equipped with an internal switching system per cell making it possible to replace the function of the inverter.

21. Device (10) according to one of claims 1 to 20, in which the generator (11) is supplied with a fuel of the diesel, jet fuel, ammonia, HMO, methanol, hydrogen, fuel oil, biomethane, biogas, or natural gas type.

22. Device (10) according to one of claims 1 to 21, in which the generator (11) is equipped with a gearbox in addition to the alternator.

23. Device (10) according to one of claims 1 to 22, in which at least one generator (11) and / or at least photovoltaic panels (12) are configured to produce electricity having a voltage less than or equal to one hundred and twenty volts.

24. Device (10) according to one of claims 1 to 23, in which at least one generator (11) and / or at least photovoltaic panels (12) are configured to produce electricity having a voltage less than or equal to eighty volts.

25. Method for producing hybrid electrical energy with photovoltaic panels (12) and at least one generator (11) with an isochronous rotating machine in response to an electrical load to be supplied, each generator comprising an alternator, characterized in that it comprises: - a step of reading, in memory, a minimum electrical power limit value to be supplied by each rotating machine generator, - a step of limiting the electrical power supplied by the photovoltaic panels according to the electrical load to be supplied and the limit value read for the minimum electrical power to be supplied by the generators, and - a step of electrical coupling of the alternator of each generator in operation.

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