AU2021107598B4 - Electrical supply system - Google Patents

Electrical supply system Download PDF

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Publication number
AU2021107598B4
AU2021107598B4 AU2021107598A AU2021107598A AU2021107598B4 AU 2021107598 B4 AU2021107598 B4 AU 2021107598B4 AU 2021107598 A AU2021107598 A AU 2021107598A AU 2021107598 A AU2021107598 A AU 2021107598A AU 2021107598 B4 AU2021107598 B4 AU 2021107598B4
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AU
Australia
Prior art keywords
converter
power
supply
directional
battery
Prior art date
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Application number
AU2021107598A
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AU2021107598A4 (en
Inventor
Stuart James Brown
Daniel Joseph Jung
Ian Sinkins
David John Treanor
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Redei Innovations Pty Ltd
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Redei Innovations Pty Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2021901411A external-priority patent/AU2021901411A0/en
Priority claimed from AU2021218138A external-priority patent/AU2021218138B2/en
Application filed by Redei Innovations Pty Ltd filed Critical Redei Innovations Pty Ltd
Priority to AU2021107598A priority Critical patent/AU2021107598B4/en
Publication of AU2021107598A4 publication Critical patent/AU2021107598A4/en
Application granted granted Critical
Publication of AU2021107598B4 publication Critical patent/AU2021107598B4/en
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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/28—Arrangements for balancing of the load in a network by storage of energy
    • H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/10—The dispersed energy generation being of fossil origin, e.g. diesel generators
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20—The dispersed energy generation being of renewable origin
    • H02J2300/22—The renewable source being solar energy
    • H02J2300/24—The renewable source being solar energy of photovoltaic origin
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • H02J7/0024—Parallel/serial switching of connection of batteries to charge or load circuit
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
    • H02J7/0048—Detection of remaining charge capacity or state of charge [SOC]
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
    • H02J7/35—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering with light sensitive cells
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/66—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E70/00—Other energy conversion or management systems reducing GHG emissions
    • Y02E70/30—Systems combining energy storage with energy generation of non-fossil origin

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Supply And Distribution Of Alternating Current (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

P1772AUA1 ABSTRACT A system 3 comprising a battery system 5, a uni-directional AC to DC converter 7 to take AC from a mains supply MS and supply DC to the battery system, and a bi directional DC to AC converter 9 to connect the battery system to at least one AC 5 load CL and one or more AC power sources 7.

Description

P1772AUI1
1
ELECTRICAL SUPPLY SYSTEM FIELD OF THE INVENTION
The invention relates to the supply of electricity.
BACKGROUND TO THE INVENTION
In some contexts, mains electricity supply is available but insufficient. By way of example, a remote dairy farm may be connected to a mains supply but be forced to serialise milk processing stages (that would more preferably be operated in parallel) so as not to exceed the permissible power draw from the main supply.
Consumers can supplement their electrical needs with battery-solar systems. Advantageously, typical such systems allow the consumer to sell their excess solar power back into the grid. Whilst advantageous for the consumer, the power supplied to the grid may be turbulent so as to degrade the overall quality of the mains-power and potentially damage mains-infrastructure. Accordingly, electrical authorities typically require consumer-level solar battery systems to be of limited capacity (e.g. 3.5kVA per phase on a SWER line) and/or comprise costly grid protection systems such as grid protection relays and power factor correction systems.
For some consumers, the mains supply plus the limited supplementary solar-battery power is not enough. Such a consumer is often left with three potentially unpalatable options of either:
* restricting their power usage;
• paying to upgrade the mains infrastructure; or
" paying for a dedicated off-grid system.
P1772AUI1
2
With the foregoing in mind, the present invention aims to provide improvements in and for the supply of electricity, or at least to provide an alternative for those concerned with the supply of electricity.
SUMMARY
One aspect of the invention provides a system comprising
a battery system;
a uni-directional AC to DC converter to take AC from a mains supply and supply DC to the battery system;
a bi-directional DC to AC converter to connect the battery system to
at least one AC load; and
one or more AC power sources.
The system may comprise the one or more AC power sources. The one or more AC power sources preferably comprise a solar-powered power source. Optionally the one or more AC power sources comprise a combustion-powered power source, e.g. diesel generator.
Preferably the uni-directional AC to DC converter is configured to galvanically isolate the mains supply.
The system may comprise a bypass for bypassing the uni-directional AC to DC converter and the bi-directional DC to AC converter to connect the at least one AC load to the mains supply. Preferably there is a control arrangement configured to limit a power draw from the mains supply.
Preferably the uni-directional AC to DC converter is preferably de-activatable to cause the bi-directional DC to AC converter to draw power solely from the battery system.
P1772AUI1
3
The battery system preferably has a voltage of at least 48V, e.g. 130V. The system may comprise a utility meter for measuring the power supplied by the mains supply. In certain embodiments the uni-directional AC to DC converter is configured to take power from both phases of a 2-phase mains supply.
In one implementation the system is connected to a SWER line.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic view of an electricity-supply system.
DETAILED DESCRIPTION
Figure 1 illustrates an electrical supply system for powering a customer load CL. The system 1 is connected to a mains supplyMS via a utility meter UM.
At the heart of the system 1 is a converter-battery system 3 comprising a battery system 5, a uni-directional AC to DC converter 7 in the form of a battery charger and a bi-directional DC to AC converter 9. Components 5, 7, 9 are mutually connected at node 11.
The battery charger 7 connects the battery 5 to the mains supplyMS whilst the converter 9 connects the battery 5 and the converter 7 to both the customer load CL and AC power sources 17. The AC power sources 17 comprise combustion generator 17a and solar-powered power source 17b. The power source 17b comprises photovoltaic solar panels and an inverter.
A control arrangement, which is preferably incorporated within the battery charger 7, provides for two distinct modes of operation. The battery charger 7 may shut down to isolate components 5, 9 from the mains supply MS to cause the converter 9 to draw power solely from the battery system 5. In this example, the charger 7 regulates power flow based on both the consumer load and the state of charge (e.g. voltage) of the battery system, e.g. the charger 7 may be configured to enable power flow when the consumer load exceeds a discharge rate of the battery system and/or the battery system is depleted below a pre-determined (e.g. voltage) threshold. Other variants of
P1772AUI1
4
the control arrangement may take account of other parameters such as mains-pricing (e.g. actual and/or anticipated pricing), solar-production (actual and/or anticipated) and/or anticipated AC load. By way of example, the battery-charging threshold may be elevated in advance of anticipated price rise, anticipated overcast weather and anticipated high AC load and then dropped when the anticipated occurs. The control arrangement may incorporate a learning algorithm(s) (i.e. artificial intelligence Al).
In another mode of operation, the inverter 9 draws power from the battery system 5 and also from the charger 7 whereby preferred embodiments of the system 3 can deliver far more power than the mains supply MS. At the same time, the converter 7, being a uni-directional converter, guards against power being fed back into the grid, e.g. guards against power from the battery system 5 and/or the power sources 17 being fed back into the grid. In this way, the systems 1,3 are entirely'behind the meter'whereby the size of the systems 1,3 is not limited by the potential to damage mains infrastructure etc. and capacity-limiting regulations that guard against such damage.
The converter 9 is a bi-directional converter whereby in the event that power from the power sources 17 exceeds the consumer load, the excess power can be fed back to the battery 5 for usage later on. Whereas typical supplementary solar battery systems comprise 120V battery systems, the present inventors have recognised that the converter 9 can operate more efficiently at higher voltages. Accordingly, a preferred variant of the present invention comprises an about 155V battery system 5. The battery system may comprise a single battery or a set of batteries, e.g. three 48V batteries.
This variant of the system 1 comprises a bypass switch 13 switchable (e.g. under the control of the control arrangement) to bypass the system 3 to directly connect the customer load to the mains supply, in this case at point 15 intermediate the utility meter UM and the converter 7. This provides for a third mode of operation that may be useful, for example, in the event of a fault within the system 3.
In this example, the mains supply comprises a single-wire earth return (SWER) line supplying electricity at a high transmission voltage, e.g. 12.7kV, and a SWER
P1772AUI1
5
transformer that reduces the voltage to a consumer voltage, e.g. 240V per phase. In this case, the transformer is a 2-phase transformer from which two phase-wires and a neutral wire emerge. This example of the system 3, or more specifically the converter 7, cooperates with all three wires to take power from both phases. Other variants of the system 3 may cooperate with single-phase or 3-phase power. In Australia, consumer voltage is typically supplied at 50Hz. Elsewhere it is frequently at 60Hz.
Preferred forms of the invention are configured to service commercial and industrial customers with 2-phase SWER main grid supply. Most preferably the customer load CL and mains supply MS have the same number of phases and frequency, e.g. a 2-phase 480Vac load side supply that reflects the 2-phase 480Vac supply input feeding into the converter 7. Alternatively, e.g. the system 1 may provide a 3-phase 415Vac to a customer load even if the input feed to the converter is 2-phase 480Vac.
Maintaining the same configuration, e.g. 2-phase 480Vac, on both sides of the system 1 minimises installation/changeover costs, e.g. client equipment may be only suited to 480Vac operation and not 415Vac 3-phase operation.
To suit applications such as farms, dairy processing and light industrial applications, the converter 7 preferably has a maximum safe capacity (MSC) of at least 15kVA. MSC refers to steady state operation without overheating etc. Economic variants to suit such applications may have an MSC of 40kVA. Likewise, the converter 9 may have an MSC of at least 15kVA, and to keep costs in check the MSC may be not more than 240kVA. Preferred variants of the solar power supply 17b are capable of delivering at least 15kVA (e.g. at most 250kVA) in good weather. Preferably the converter 9 and the inverter of the solar power supply 17b have about the same MSC.
The invention is not limited to the exemplary features described herein. Rather the invention is defined by the claims.
The term 'comprises' and its grammatical variants has a meaning that is determined by the context in which it appears. Accordingly, the term should not be interpreted exhaustively unless the context dictates so.

Claims (5)

P1772AUI1 6 CLAIMS
1. A system comprising
a battery system;
a uni-directional AC to DC converter connected to a mains supply to take AC from the mains supply and supply DC to the battery system;
a bi-directional DC to AC converter to connect the battery system to
at least one AC load; and
one or more AC power sources.
2. The system of claim 1 comprising the one or more AC power sources;
wherein the one or more AC power sources comprise a solar-powered power source.
3. The system of claim 1 or 2 wherein the battery system has a voltage of at least 130V.
4. The system of claim 1, 2 or 3 comprising the mains supply, wherein the mains supply comprises a SWER line to supply electricity to the uni-directional AC to DC converter.
5. The system of claim 4 wherein the mains supply comprises a 2-phase SWER transformer to connect the SWER line to the uni-directional AC to DC converter; and
the at least one AC load is at least one 2-phase load.
17a 17b 17
1
13 CL
MS UM 15 1/1
7
9 3 5 11
FIGURE 1
AU2021107598A 2021-05-12 2021-10-29 Electrical supply system Active AU2021107598B4 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2021107598A AU2021107598B4 (en) 2021-05-12 2021-10-29 Electrical supply system

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
AU2021901411A AU2021901411A0 (en) 2021-05-12 Electricity supply system
AU2021901411 2021-05-12
AU2021218138A AU2021218138B2 (en) 2021-05-12 2021-08-19 Electrical supply system
AU2021107598A AU2021107598B4 (en) 2021-05-12 2021-10-29 Electrical supply system

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
AU2021218138A Division AU2021218138B2 (en) 2021-05-12 2021-08-19 Electrical supply system

Publications (2)

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AU2021107598A4 AU2021107598A4 (en) 2022-01-06
AU2021107598B4 true AU2021107598B4 (en) 2022-06-16

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110133556A1 (en) * 2009-12-04 2011-06-09 Samsung Sdi Co., Ltd. Energy storage system
US20150295451A1 (en) * 2012-10-02 2015-10-15 Panasonic Intellectual Property Management Co., Lt Power control system and solar power generation system
CN206226030U (en) * 2016-11-16 2017-06-06 宁波拜特测控技术股份有限公司 A kind of LAN energy-storage system
CN111355256A (en) * 2020-03-09 2020-06-30 台达电子企业管理（上海）有限公司 High-voltage direct-current power transformation device, power system and control method of power system
WO2021008235A1 (en) * 2019-07-12 2021-01-21 阳光电源股份有限公司 Dc coupling off-network hydrogen production system and power supply device for control cabinet thereof, and control method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110133556A1 (en) * 2009-12-04 2011-06-09 Samsung Sdi Co., Ltd. Energy storage system
US20150295451A1 (en) * 2012-10-02 2015-10-15 Panasonic Intellectual Property Management Co., Lt Power control system and solar power generation system
CN206226030U (en) * 2016-11-16 2017-06-06 宁波拜特测控技术股份有限公司 A kind of LAN energy-storage system
WO2021008235A1 (en) * 2019-07-12 2021-01-21 阳光电源股份有限公司 Dc coupling off-network hydrogen production system and power supply device for control cabinet thereof, and control method
CN111355256A (en) * 2020-03-09 2020-06-30 台达电子企业管理（上海）有限公司 High-voltage direct-current power transformation device, power system and control method of power system

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