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DC distribution networks in industries and energy-intensive plants: a useful and necessary innovation. |  |
| DC distribution networks in industries and energy-intensive plants: a useful and necessary innovation. | ||
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.... Introduction .... High energy efficiency is a must! Consuming more energy than an end user actually needs is not only an unnecessary cost and a source of unnecessary pollution, but also has political implications that ultimately lead to energy wars. We must therefore limit energy purchases from abroad as much as possible and exploit renewable energy sources available locally as much as possible.
Technically, we have other options for saving a few percentage points of energy by adopting direct current (DC) electricity distribution in factories.
.... In summary .... - Instead of the traditional 400 VAC, 50 Hz power distribution in Europe and other countries, DC power distribution could be used, with only two cables instead of three cables for power sharing.
- Machine manufacturers will no longer have to deal with markets with frequencies of 50 Hz or 60 Hz at different voltages and with different transmissions ratios; a single power supply will provide the correct DC voltage required by the machinery, which will therefore be of a single, standardized type worldwide.
- The energy efficiency of the system (distribution network plus machinery) will improve by several percentage points.
- The cost of power electronics on the machinery will be reduced gradually, as the various distributed current rectifiers will no longer be necessary.
- The cost of power wiring in the factory and its installation will be reduced, as there will be fewer cables to install and a shorter overall length.
- With the same existing electric motors controlled by inverters, a power increase of up to 20% can be achieved, while reducing size, weight, and price, thanks to the increased available DC voltage.
- The vast majority of various power quality issues will be solved at the root, and it will be much easier to add small energy storage devices (capacitors, supercapacitors, or batteries) where useful, or large storage devices to power the factory for several days in the event of a total power outage.
- In new constructions with new machinery, or in complete renovations of some departments with machinery upgrades, DC power supply is advantageous both in terms of purchase price and lower energy costs.
- It will be easier to connect renewable sources to the system, even of different types and power ratings, even at a later date. Photovoltaic panels will supply energy to the factory without the need for inverters.
Many major companies around the world are working on this major project, which requires standardizing voltages and protection systems to ensure the necessary interchangeability of components. |
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It has been demonstrated that eliminating unnecessary converters not only leads to greater energy efficiency, but also to a reduction in space and costs, as well as increased reliability, as fewer components are subject to potential failure. This comparison clearly shows the potential savings achieved by adopting the DC philosophy:
Currently, only a few companies are able to convert their internal factory networks to operate exclusively with DC; it will be several years before all the necessary components can be easily found at competitive prices. For example, super-fast fuses for high DC currents at the required voltages already exist, but they are not currently manufactured in industrial-grade containers (these are fuses with a small explosive charge inside, similar to airbags).
Nearly all of the world's leading electrical engineering and power electronics companies are holding working groups to determine standardized voltage levels and protection specifications, which will need to be interchangeable with competing products. Some cable manufacturers already have cables designed for DC distribution in their catalogs, which requires design solutions to ensure long cable life, as the DC voltage always has the same polarity and is therefore subject to phenomena not seen in AC cables. There will also be savings on cables, both in terms of cable cost, given their shorter overall length, and lower installation costs.
This innovation will necessarily lead to greater interchangeability between equipment from different manufacturers, which will all operate fairly similarly, at least for general applications. Since current 50 Hz motors will be able to deliver approximately 20% more power, and since the price of simplified inverters for DC-only power will be increasingly affordable and their reliability will be much higher than current ones, and considering that inverters are sized for current, so increasing from 50 to 60 Hz does not increase their size or price, the vast majority of three-phase motors will be equipped with inverters, with advantages in terms of performance and energy efficiency. In electric vehicles, some inverters have achieved performance levels unimaginable just a few years ago; for example, an inverter for a 300 kW motor is the size of a shoebox. All things considered, for the vast majority of motors used in industry, inverters will be very small, barely larger than current terminal boxes, and will therefore almost always be mounted directly on the motors, except for special high-temperature applications or those with specific requirements.
I suggest to companies in the electrical and electronics sector begin evaluating this substantial change before it's too late. There are already examples of DC solutions specially in the naval sector.
(Mario Maggi, https://it.linkedin.com/in/mariomaggi ) ------------------------------------------------------------------------------------------------------------------------------------------------------------------ Can a DC voltage be transformed into another voltage, as with an AC transformer?
The "DC transformer" exists and is an industrial product from the Spanish company Epic Power, offered by AXU Snc in Italy: https://www.axu.it/ep/ The well-known Japanese multinational Yaskawa Electric - which never advertises other people's electronic products - publishes a special application on its website citing the name of the electronics manufacturer Epic Power: https://www.yaskawa.eu.com/battery-testing-outside-the-laboratory-the-system-sustainable-industry-needs_u14273 , a sign that we are dealing with a truly interesting DC/DC converter. Normally the "direct current transformer" which is a bidirectional DC/DC converter, is offered in this form, ready for installation in an electrical panel or in a machine:
Many modules can be paralleled to achieve power outputs greater than one megawatt in a 19" rack cabinet:
Initiatives around the world and information from major companies Standardization roadmap DKE in Germany Conversion from AC to DC for DC microgrids - Schneider Electric
Applications DC microgrids DC Experience center in Amsterdam by Schneider Electric Articles IEEE Xplorer: Renewable Power Routing from a DC Microgrid to an Industrial Cluster IEEE Xplorer: Multi-criteria Methodology for the Sustainable Powering of an Industrial DC Microgrid Cluster Nature: Adaptive grid resilient based protection method for multi fault scenarios in medium voltage quintuple DC microgrid systemData Center Frontier: https://www.datacenterfrontier.com/sponsored/article/55308211/high-voltage-dc-power-the-future-of-data-center-power-architecture Blog Mouser Electronic: Resources for DC Microgrid Magazine "Fare Elettronica": DC Microgrid: il prossimo passo nell’evoluzione energetica Architecture NVIDIA: Architectural Imperative of 800 VDC and Integrated Energy Storage Diagrams data center NVIDIA: nvidia-800-v-hvdc-architecture-will-power-the-next-generation-of-ai-factories/ EO Elettronica Oggi - Microgrid in DC: https://elettronica-plus.it/brochure/eo/533/32/#zoom=zC Italian Magazine "Economy" - 20260501 - Pages 57...59 - Considerazioni su adozione della DC (purchase online)
(----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- MOOC - Free online teaching on DC microgrids On YouTube, thanks to Current/OS: 2 Voltages 6 Earthing
* Solutions offered by STMicroelectronics ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Basic information is provided to companies free of charge via email. For paid DC network consulting requests, please write to info@axu.it |
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REPORTS MTBF for electronics equipments and cards |
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With the increasing and continuous development of technology, especially electronic ones, and with higher expectations by the end users, the equipment manufacturers have to face more frequently the reliability matters. More and more often, even at the regulatory level, the MTTF and MTTR values are required. The term "reliability" commonly indicates both the survival characteristic of a component or a system that the discipline that describes in mathematical terms. The reliability techniques should be applied in the design phase, allowing to detect, with good approximation in addition to any possible problems, the average lifetime of the final product. An expert company in the field of predictive reliability, provides you with the know-how gained in over 20 years of work and research in this specific field.
Generally for the "prediction MTBF" it prompted as per HDBK-MIL217F standard (N1 / 2); usually it is suggested to use the simplest calculation mode, the "Part Count", which presupposes on the part of the customer count of the number of components for each type of component (eg .: ceramic capacitors), using the BOM (Bill of Materials).
The MTBF calculation leads to the conclusion that the expected life is always very tied to the operating temperature. At high temperatures the expected life is significantly reduced. We observe that the MTBF value is directly correlated to the expected life.
The document to be completed and returned to AXU Srl, indicating also the reference of the working environment, will be sent on request, asking it at info@axu.it
------------------ Acronyms -------------------
MTBF = Mean Time Before Failure
MTTF = Mean Time To Failure
MTTR = Mean Time To repair
MTTFd - Mean Time To dangerous Failures
MCBF = Mean Cycles Before Failure = MTBF x cycles per hour
For further informations, please email a detailed inquiry to info@axu.it
-------------- How to proceed to get one report ----------------
1) Check if our offer is suitable for you (type of report, price, conditions), as per our offer rqd585
2) Please fill all information requested in the document rqd584 and send it to info@axu.it
3) Please make the payment for the amount selected, to AXU S.r.l. - Via Postumia 12 - I-20153 Milan - Italy - V.A.T. code IT13391110155 - BIC/SWIFT BCITITMM https://www.axu.it/en/contacts-address
4) As soon as we will see your payment in our e-banking, we will start our job that will be delivered in few days, as stated on our offer.
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OFFER FOR MTBF REPORTS for electronics equipments and cards |
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Our document rqd585
We are please to offer to you:
1) MTBF values predictions as per HDBK-MIL217F - "Part Count" mode - for one single electronic board, based on the AXU document rqd584 filled by the customer, at netto price of 340,00 euros
2) MTBF prediction for multiple boards, working independently and separately:
- for 2 boards, total price 640,00 euros
- for 3 boards, total price 920,00 euros
- for 4 boards, total price 1200,00 euros
- for more boards, please ask a quotation.
3) MTBF prediction for multiple boards, working all together (one report for each PCB, and one report for the total assembly)
- for 2 boards + assembly, total price 900,00 euros
- for 3 boards + assembly, total price 1180,00 euros
- for 4 boards + assembly, total price 1480,00 euros
- for more boards + assembly, please ask a quotation.
4) Board modal analysis, analysis of a pcb subject to vibrations and identification of most stressed areas. Please send a quoted topographlcal drawing or scketch (file .pdf or .dxf) and the net list (file .doc or .pdf) indicating anchorage areas and copper percentage, at netto price of 230,00 euros each.
VAT Tax 22% will be added for Italian companies and for non-EC companies over these prices.
To proceed, please follow instructions HERE
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INSTRUCTIONS TO OBTAIN MTBF REPORTS for electronics equipments and cards |
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1) Check if our offer is suitable for you (type of report, price, conditions), as per our document rqd585
2) Please fill all information requested in the document rqd584 and send it to info@axu.it
3) Please make the payment for the amount selected, to AXU S.r.l. - Via Postumia 12 - I-20153 Milan - Italy - V.A.T. code IT13391110155 - BIC/SWIFT BCITITMM http://www.axu.it/en/contacts-address
4) As soon as we will see your payment in our e-banking, we will start our job that will be delivered in few days, as stated on our offer.
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REPORTS MTBF - MTTFd per schede elettroniche |
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Il crescente e continuo sviluppo delle tecnologie, in particolare quelle elettroniche e soprattutto le maggiori aspettative da parte dell’utente finale, portano i costruttori di apparecchiature a dover affrontare il problema dell’affidabilità con sempre maggior frequenza. Sempre piu' spesso, anche a livello normativo, vengono richiesti i valori MTTF e MTTR, la cui somma da' l'MTBF. Con il termine AFFIDABILITA’ (Reliability in inglese), comunemente si indica sia la caratteristica di sopravvivenza di un componente o di un sistema che la disciplina che descrive in termini matematici gli stati limite dei sistemi e che valuta la distanza di tali stati dallo stato di esercizio dei sistemi stessi. Le tecniche di affidabilità dovrebbero essere applicate già in fase progettuale, permettendo di individuare, con ottima approssimazione, oltre ad eventuali problemi la possibile vita del prodotto finale. Un'azienda esperta nel settore dell’affidabilita' predittiva, mette a Vostra disposizione il know-how acquisito in oltre 15 anni di lavoro e ricerca.
Generalmente viene richiesto lo standard HDBK-MIL217F, di solito si suggerisce di usare la modalita' piu' semplice, la "part count", che presuppone da parte del Cliente il conteggio del numero di componenti per ciascuna tipologia di componente (es.: condensatori ceramici).
Il documento da completare e restituire ad AXU S.r.l., con l'indicazione dell'ambiente di riferimento, viene inviato a richiesta.
I calcoli MTTFd possono essere determinati direttamente per componenti elettrici o elettronici facendo parte sia di un numero di componenti o di un Failure Mode and Effects Analysis (FMEA). Per i componenti meccanici ed elettromeccanici (ad esempio i solenoidi), idraulici, e pneumatici che hanno un profilo operativo ciclico, e' piu' difficile fornire un valore MTTFd poiche' dipende dalla frequenza con cui il dispositivo viene utilizzato nel tempo.
Il calcolo MCBF e' interessante per quei componenti che sono soggetti ad un invecchiamento legato piu' al numero di cicli che al tempo, come ad esempio i rele' ed i contattori.
Si eseguono calcoli anche per componenti specifici - per esempio i connettori elettrici - e calcoli associati a prove pratiche di invecchiamento - per esempio le cinghie di trasmissione soggette alla luce solare con raggi UV.
------------------ Acronimi -------------------
MTBF = Mean Time Before Failure
MTTF = Mean Time To Failure
MTTFd - Mean Time To dangerous Failures
Durata media di funzionamento prima che capiti un guasto casuale potenzialmente pericoloso e non un guasto generico. Puo' essere riferita ad un singolo componente, oppure a un'apparecchiatura oppure al sistema completo.
MCBF = Mean Cycles Before Failure = MTBF x cicli per ora
----------- Prezzi dei servizi - Offerta rqd585 -------------------
1) Calcolo dei valori MTBF secondo le norme HDBK-MIL217F in modalità "Part Count" - per una singola scheda elettronica, basato sui valori indicati dal cliente sul documento AXU rqd584, al prezzo netto di 340,00 euro +IVA
2) Calcolo dei valori MTBF per schede multiple, utilizzate indipendemente e separatamente:
- per 2 schede, prezzo totale 640,00 euro +IVA
- per 3 schede, prezzo totale 920,00 euro +IVA
- per 4 schede, prezzo totale 1200,00 euro +IVA
- per più schede, chiedere una quotazione.
3) Calcolo dei valori MTBF per schede multiple, utilizzate insieme (un report per ogni PCB, ed un report per l'apparecchiatura completa)
- per 2 schede + complessivo, prezzo totale 900,00 euro +IVA
- per 3 schede + complessivo, prezzo totale 1180,00 euro +IVA
- per 4 schede + complessivo, prezzo totale 1480,00 euro +IVA
- per più schede + complessivo, chiedere una quotazione.
4) Calcolo dei valori MTBF in modalità diversa dalla "Part count": chiedere una quotazione.
-------------- Come procedere per ottenere un report ----------------
1) Verificare se la nostra offerta rqd585 è adeguata per le Vostre esigenze (tipo di report, prezzo, condizioni).
2) Compilare tutte le informazioni tecniche richieste nel documento rqd584 e inviarlo via email a info@axu.it
3) Inviare l'ordine formale via email, precisando quale report è richiesto, prezzo e dati fiscali completi dell'azienda, compreso il codice fiscale
4) Inviare il pagamento tramite bonifico ad AXU S.r.l. - Via Postumia 12 - I-20153 Milano - Partita IVA 13391110155 - https://www.axu.it/it/home-italiano/pagamenti-ad-axu-s-r-l
5) Appena vediamo che il bonifico è arrivato sulla nostra banca online, effettueremo i calcoli entro pochi giorni, come concordato, ed invieremo la fattura quietanziata.
Per altre informazioni, inviare un email con una richiesta dettagliata a info@axu.it
