Herbert Leopold GABRYŚ
Power industry in Poland in 2017 ... basing upon the results for 2016 and not only
Made is an attempt to assess the situation of the Polish power industry against the background of results achieved in this sector in the year 2016. From the energy balance we can conclude that the domestic consumption was bigger than the electric energy production by 1,2%. Increased was also the production coming from industrial power plants. For the first time in recent years the trend to substantially increase the production of energy from renewable sources has been stopped and, if we look at changes in the structure of this production, the amount of energy produced by wind farms was bigger, there were no changes in biomass energy production but the one coming from biomass co-combustion was smaller. The wholesale electric energy market was characterised by lower sale of the energy generated by commercial power plants. Average weighted price of electric energy in the wholesale trade was higher by 4%. The amount of electric energy sold by retail providers to end-users was bigger by 4,2 TWh. Prices of the energy in the retail market were lower by almost 5 zł/MWh i.e. by 2,3%. Altogether, the whole sector showed a profit equal to 6,18 bln zł while there was a loss for the year 2015. Excluding the lack of explicit strategic government decisions concerning, first of all, the future of power generation in Poland, a great deal of good happened in the power industry in 2016. Investments in the network infrastructure develop intensively, mostly in the area of generation in the conventional power industry. However, the Polish economy cannot feel safe with respect to security of supplies. There are still many challenges to be met, in particular in the field of costs connected with the climate and energy package policy of the EU.
Keywords: condition of the Polish power industry, challenges and costs, climate and energy package policy of the EU
Jerzy RYCHLAK, Marek KOMARZYNIEC, Alojzy WOLC
Acceptance tests of generating units before connection to a network and during their subsequent work in a power system in the light of the EU Regulation (EC) 2016/631 requirements
The EU Regulation 2016/631 of 14 April 2016 established a network code concerning demands on connecting of generating units to a network and it entered into force on 17 May 2016. The established requirements for generating units are, among the others, to contribute to maintain sufficient system security, facilitate proper functioning of electric energy internal market between synchronized areas as well as within their borders and also improve a system functioning cost efficiency. Described are the substantive scope of this document, technical requirements and a procedure to obtain a permit for use for the purpose of connecting to a network. Presented is also the range of activities that must be realized to ensure compliance with the requirements. Over the years, a number of verification procedures has been worked out in the Polish power system that may continue to be used. But, for the new requirements it will be necessary to elaborate the new ones and the full picture of the being in force generating units acceptance practice will only emerge after a two years’ transitional period.
Keywords: the EU Regulation 2016/631, network code, power system security
Jerzy NOWAK
Communication networks according to the IEC61850 standard in a 400/220 kV substation secondary systems
Communication between bays for distributed functions realization and the communication to a station level is an important problem in the architecture of 400 kV (220 kV) switchyard secondary systems but the most important is a very complicated secondary systems architecture inside a 400 kV (220 kV) switchyard bay. This architecture must be realized under circumstances of frequent IED replacement or secondary systems rebuilding in stages with a limited outage time. Reminded are problems that are independent of the fact whether communication networks or traditional wired connections were applied. Presented is also the architecture of secondary systems inside a 400 kV switchyard bay with the use of process and substation buses according to the IEC61850 standard. Change-proof protection and control standard solutions are the basis of this architecture. Provided is an information about the recent practical realization of the IEC61850 standard implementation in an existing 345/138 kV substation in the USA.
Keywords: 400 kV switchyards, secondary systems, communication networks, IEC61850 standard
Jerzy TRZESZCZYŃSKI, Adrian SOBCZYSZYN, Kamil STASZAŁEK, Radosław STANEK, Sławomir RAJCA
Diagnostics of long time operated power units planned for flexible operation
Changes in the technologies of production and distribution in power sector are accompanied by challenges characteristic for the Economy 4.0. The recipient of the energy has growing ambitions to generate it as well. Coal fired power units become less and less source of energy and increasingly they are stabilizing the power system. In Polish National Power System this is a challenge to be met, among others, by 200 MW power units operated for more than 200 000 hours passing numerous upgrades and modernizations. Recent, which come to an end, are performer to meet requirements of the IED 2010/75/EU. Next upgrades will be aimed at fulfillment of BAT Conclusions. Diagnostics should allow both to identify new types of damages and to process information in on-line mode, remote monitoring and automatic creation of knowledge integrated with economic indicators and risk evaluation. For this purpose we performed, among others, the following activities:
• testing of main elements of boilers, pipelines and turbines operated for more than 250 000 hours,
• development of technologies to extend lifetime of cast-steel elements of turbines over 300 000 working hours,
• development of ‘Guidelines for life extension of critical elements of thermo-mechanical power equipment’ with emphasis on:
– failure analysis,
– power chemistry issues,
• development of IT systems supervising the technical condition of thermo-mechanical equipment of power units,
• development of Internet portal to integrate information and knowledge generated with support of such systems.
Special attention was paid to the analysis of working condition connected with flexible operation. We have proposed our own original solution consisting of synchronous detailed analysis of working condition, scope and cost of maintenance and the price of energy.
Keywords: power units, flexible operation, diagnostics, Pro Novum information platform LM System PRO+®
Radosław STANEK, Jerzy TRZESZCZYŃSKI
Pro Novum experience in performing diagnostic supervision of BB-1150 and OP-650 boilers heating surfaces based on risk analysis
The current technical condition of critical elements that influence reliability of power units can be monitored in an on-line mode. This type of service has been provided by Pro Novum company for the last 10 years, also in the form of LTDS (Long Time Diagnostic Service). The latest version of this service, which includes a current damage/breakdown risk analysis, was implemented on modernized boilers working in 200 MW and 360 MW power units. The knowledge ensured by the service enables maintenance of boiler heating surfaces according to the strategy RBM (Risk Based Maintenance) that allows a rational compromise between proceedings resulting from the real technical condition of an installation, Technical Inspection regulations and production considerations. Presented is the several years’ Pro Novum experience in providing of this type of service.
Keywords: boiler heating surfaces, diagnostic supervision, Long Time Diagnostic Service
Krzysztof BRUNNÉ, Kamil STASZAŁEK, Przemysław SYTY
Special testing of long operated steam boiler drums
Technical condition assessment and service life prediction of steam boiler drums needs not only performing the basic diagnostics and analysing the stress state but also an appropriate use of informations concerning operating conditions, repair works and failures. Under some justified circumstances it is recommended to carry out a special testing of long operated drums i.e. taking samples for destructive tests with the aim to determine real mechanical properties of the material after a long-term work. But determination of strength properties and the temperature of material transition into the brittle state should take place only in strictly defined and justified cases because every time you cut some material out for tests you interfere into a construction and very often it can only be repaired by welding. In such situations it is worth while to consider a possibility to take a sample from the most efforted place, it is from the potential damage zone – an edge of the opening in the water zone. Presented are results of destructive tests conducted on samples taken from four boiler drums and drawn are subsequent conclusions.
Keywords: steam boiler drums, special testing, strength properties determination
Wojciech BRUNNÉ
Vibrations of double-reheat steam pipings of power units working in regulation. Causes and prevention methods
Vibrations of steam pipings, especially of the double-reheat steam ones, have occurred during their entire operating time but, until now, such cases were relatively rare or their amplitude was practically of no significance. The imposed by the operators work in the so-called regulation – very deep sometimes – of project units for the base operation generates numerous, often not fully perceived and defined, problems. One of the consequences of double-reheat power units operation in regulation is a significant increase in double-reheat steam pipelines vibrations incidents, both in terms of occurrence frequency and their amplitude, affecting a growing number of users. Made is an analysis of piping vibrations causes, discussed is a human error as a reason of vibrations occurrence and technical conditions that can result in vibrations of double-reheat steam pipings during their start-up.
Keywords: steam pipelines vibrations, double-reheat steam cycle, double-reheat power units work in regulation