Rectifier on a Heat-into-Electricity Thermionic Converter Basis
Creating the High Current Low Voltage Rectifier on a TEC Basis (TEC-Rectifier)
Tech Area / Field
- NNE-MEC/Miscellaneous Energy Conversion/Non-Nuclear Energy
8 Project completed
Senior Project Manager
Alexandrov K A
State Enterprise Krasnaya Zvezda, Russia, Moscow
- Russian Academy of Sciences / Physical Technical Institute, Russia, St Petersburg\nFEI (IPPE), Russia, Kaluga reg., Obninsk
- [Individual specialist]
Project summaryThe aim of this project is the creation of the alternative high current low voltage rectifier for use by direct current loads, for example, in galvanic industry.
An engineering approach is based on the use of the heat-into-electricity thermionic converter (TEC) as a rectifier valve, which will make it possible to completely exclude the voltage loss in the rectifier, as well as to achieve the efficiency of about 100%.
The volumes of consumption of the low voltage direct current electric power in industry are very large: the galvanic industry, the electrolytic production of non-ferrous metals. Thus, in the galvanic production of the USA automotive industry alone the yearly electric power consumption is estimated at 5 billions of US dollars (the data were received in 1989 from “Kiser Research Inc.”).
Standard commercial rectifiers for galvanics are conventionally designed for the currents of kiloamperes and rectified voltages of 3 to 12 V. They mostly use as rectifier valves the powerful silicon thyristors possessing the high direct voltage drop (~ 2 V). Hence their efficiency is not high and makes 80 to 90%. The replacement of these rectifiers by the more economical ones promises an enormous electric power saving, even if the efficiency will be increased only by 1 to 2%.
The problem of elimination of the electric power loss when rectifying low voltages can be cardinally solved by the use of heat-into-electricity thermionic converters as rectifier valves. At the TEC anode temperature is TA < 500 550oC, the reverse current in it is negligible and the anode operates as an ideal rectifier valve with the zero direct voltage drop. This makes it possible to completely exclude the loss of rectified voltage at rectifier valves and to achieve the rectifying efficiency of 100%.
The heat, which was not converted into electricity, is released at the anode, from which it needs to be removed. This heat from the anode (and from the combustion chamber, in which the TEC cathodes are heated) can be used both for technological needs in the galvanic industry itself (where the heat consumption is very large and covered now at the expense of electric power or the organic fuel combustion) and, in principle, for other various purposes, as this heat is highly potential (~500oC) - up to the electric power generation in the conventional steam turbine cycle .
Hence the TEC based rectifiers should give the electric power saving of 10 to 20%. Correspondingly, introduction of the proposed technology can give on the global scale the saving of tens of billions of kilowatt-hours of electric power.
The organizations - participants of the Project on a prolongation of many years are engaged in problems TEC with reference to different engine installations. In particular SE “Krasnaya Zvezda” together with SSC RF IPPE has developed thermionic reactors «ТОPАZ», which one successfully worked on satellites of a series «Kosmos» #1818 and 1867. The competence of the participants of the Project of the given area is confirmed also large list of the reports, patents, publications.
Lines of investigation:
1. The employment of fundamental investigations on the physics of direct heat-into-electricity conversion.
2. The employment of design solution of the TECs being employed for direct purposes and possessing the performance best suited to a TEC-rectifier.
3. Investigations in the field of design, material study and technological problems on creating the TEC-rectifier suitable for the purposes of galvanic industry and creation of the TEC tailor-made for the rectifier valve.
The expected results of the work under this Project are as follows:
1. Creating and testing of the full-scale TEC-rectifier mock-up on a basis of the direct heat-into-electricity conversion technologies, both available and being developed.
2. The prototype TEC rectifier module development, creating and testing under the conditions of galvanic production.
3. Justification of the possibility of the use in galvanic industry of more effective TEC-rectifiers as alternatives to conventional rectifiers.
4. Recommendations on application of the developed TEC-rectifier production process in mass-production.
Scientific importance of this Project is determined by the development of fundamental matters and latest technologies both in the field of direct heat-into-electricity conversion and direct current low voltage power engineering.
Commercial proficiency of this Project is conditioned by the prospect of applying its results in industrial processes connected with consumption of the direct current low voltage electric power.
The participation in the Project will allow the «weapon» scientists and experts of SE “Krasnaya Zvezda” and SSC RF IPPE to redirect the abilities on nonpredatory activity for a long time, to fix communications with international scientific community, will promote the solution of national and international problems in the field of economies of the electric power, environmental protection.