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United States Patent (19) (11) 4,024,410 Dahlberg (45) May 17, 1977

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United States Patent (19) (11) 4,024,410 Dahlberg (45) May 17, 1977 United States Patent (19) (11) 4,024,410 Dahlberg (45) May 17, 1977 54 ALTERNATING CURRENT ENERGY (56) References Cited ConVERTER UNITED STATES PATENTS (76) Inventor: Reinhard Dahlberg, Innere 2: 3: Ellio: Bergstrasse 32,7101 Flein, Germany 3702939 1/1972 Darrow. 30712 1. Primary Examiner-William M. Shoop 22) Filed. Feb. 19, 1975 Attorney, Agent, or Firn-Spencer & Kaye (2) Appl. No. 550,941 57 ABSTRACT An alternating current energy converter comprising a (30)30 ForeignO Applicationpplication Priorityty DaData whichdirect isenergy so connected converter, into thean alternatinginternal resistance current cirof June 5, 1974 Germany .......................... 2427O60 cuit that current flows as rectified current therethrough and the reactance of the alternating current circuit is 52 U.S. C. .................................... 30712; 324/119 greater than the resistance of the direct energy con (5) Int. Cl'........................................... H02J 3/02 verter. 58) Field of Search ................................... 3077-5, 307 f45, 72, 73,77; 323/32; 324/119 16 Claims, 21 Drawing Figures U.S. Patent May 17, 1977 Sheet 1 of 9 4,024,410 '88 eaaaaaaa ZZZZZZZZZZZZ555E U.S. Patent May 17, 1977 Sheet 2 of 9 4,024,410 T T XOXOX Fig.5f U.S. Patent May 17, 1977 Sheet 3 of 9 4,024,410 ...) XXXXXXXX" XXXXXX i .xxXXZXXX XXX: 3XXXX. U.S. Patent May 17, 1977 Sheet 4 of 9 4,024,410 Fig.5 U.S. Patent May 17, 1977 Sheet 5 of 9 4,024,410 Fig.8 U.S. Patent May 17, 1977 Sheet 6 of 9 4,024,410 U.S. Patent May 17, 1977 Sheet 7 of 9 4,024,410 U.S. Patent May 17, 1977 Sheet 8 of 9 4,024,410 U.S. Patent May 17, 1977 Sheet 9 of 9 4,024,410 Fig.15 8 2 5327 -- 000OOOOOOOOC soon 2 N 5 15 G 2 18 12-12 59 sogo.G. C 42 S42 O 3. Figle 4,024,410 1 2 FIG. 4 shows schematically an embodiment of the ALTERNATING CURRENT ENERGY CONVERTER invention using two thermo electric generators with interruption points, BACKGROUND OF THE INVENTION FIG. 5 shows schematically an embodiment of the This invention relates to alternating current energy invention using thermionic diode batteries, converters. The so-called "direct energy conversion" FIG. 6 shows schematically an embodiment of the with thermo-elements, thermionic diodes, photoele invention using solar cells, ments, fuel cells, radio nuclide batteries, magneto FIG. 7 shows schematically an embodiment of the hydrodynamic converters and so on today still has a invention using laser diodes, series of disadvantages. All direct energy converters O FIG. 8 shows schematically an embodiment of the produce direct current. In practice however, in the invention using fuel cells, majority of all applications, alternating current is used, FIG. 9 shows schematically an embodiment of the which must be produced first from the direct current by invention using lead accumulators, means of expensive inverters. Some direct energy con FIG. 10 shows schematically an embodiment of the verters moreover also produce only an inconveniently 15 invention using radio-nuclide battery, small direct voltage - such as, e.g. thermo-elements - or, FIG. 11 shows schematically an embodiment of the however, an inconveniently large direct voltage - such invention using two MHD converters, as, direct nuclide batteries. Also the internal resistance, FIG. 12 shows schematically an embodiment of the rising in fuel cells as a result of the polarisation of the invention using an MHD converter operating with an electrodes with stronger outer loading, is disadvanta 20 open plasma jet, geous and inconvenient. The high efficiency of the FIG. 13 shows schematically an embodiment of the energy conversion of fuel cells is, as a result thereof, invention in the form of a resonant nuclear power sta capable of being realised only for relatively small outer tion, loads. FIG. 14 shows schematically an embodiment of the A too small efficiency of the energy conversion is 25 invention in the form of a resonant fusion power sta generally speaking the most difficult predominant dis tion, advantage in all direct energy converters. FIG. 15 shows schematically an embodiment of the The present invention starts from the knowledge that invention as a turbine, and an improvement in the efficiency of direct energy con FIG. 16 shows schematically an embodiment of the verters is possible if it is possible to reduce the electri 30 invention operating as a nuclearjet power plant. cal internal resistances of the direct energy converters. DESCRIPTION OF THE PREFERRED EMBODIMENTS SUMMARY OF THE INVENTION Basically the invention proposes an alternating cur It is an object of the invention to provide an "alter 35 rent energy converter in which the electrical internal nating current energy converter' with reduced internal resistance of a direct energy converter is connected resistance and which obviates some or all of the above into an alternating current circuit in which means are described disadvantages of direct energy converts. provided by which a current flows as a rectified current According to a first aspect of the invention, there is through said electrical internal resistance of said direct provided an alternating current energy converter con 40 energy converter and in which a reactance is provided prising a direct energy converter, an alternating current for limiting the current in said alternating current cir circuit in which the internal resistance of said direct cuit. energy converter is connected for current flow, as recti The following examples will now be described, refer fied current therethrough with a reactance of said alter ring to the drawings: nating current circuit for restriction of the intensity of 45 said rectified current. EXAMPLE 1 According to a second aspect of the invention, there In FIG. 1, 1 and 2 are the thermo-legs of a thermo is provided an alternating current energy converter, electric generator. The hot contact points of the gener characterised in that the electrical internal resistance ator are maintained at the temperature T, the cold of a direct energy converter is so connected into an 50 contact points of the generator are kept at the tempera alternating current circuit that the electrical alternating ture T, and the generator has a floating voltage of 100 current flows as rectified current through said electri volts. Its internal electrical resistance, which is formed cal internal resistance of said direct energy converter from the sum of all the resistances of the thermolegs 1 and in that the reactance of said alternating current and 2, amounts to 5 ohms. The capacitor 4 has a capac circuit is greater than the electrical internal resistance 55 itance of 144 microfarads and a capacitative reactance of said direct energy converter. of 22 ohms at 50 hertz. The alternating current source 3 has an effective controllable voltage of 0 to 440 volts BRIEF DESCRIPTION OF THE DRAWINGS and a frequency of 50 hertz. The electron current S is The invention will now be described in greater detail, fed by means of the switches 7 and 8 which are opened by way of example, with reference to the drawings in and closed in push-pull in each case on the zero axis which: crossover of the alternating current, during the first FIG. 1 shows schematically an embodiment of the half wave just as the electron current 6 is fed during the invention using a thermo electric generator, second half wave in the same direction through the FIG. 2 shows schematically an embodiment of the internal resistance of the thermoelectric generator. The invention using a Peltier column or thermopile, 65 direction of the currents 5 and 6 through the internal FIG.3a to 3f show schematically embodiments of the resistance of the thermo-electric generator is so chosen invention using thermo elements with at least one inter that the direct voltage of the thermo-electric generator ruption point, is added to the alternating voltage in each half wave. If, 4,024,410 3 4 in the case of the opened switch 10, the alternating electron currents 11 and 12 flow through the high vac current source 3 is adjusted to an effective voltage of uum rectifiers 8 and 9 which are connected in push 440 volts, then an effective alternating current of 20 pull, in the positive and negative phase or half wave in amperes flows through the alternating current circuit. one direction through the elements legs 1 and 2 of the The voltage drop across the internal resistance of the Peltier column. The internal resistance of the Peltier thermo-electric generator is, as a consequence of this column is extremely high at low voltages, because the alternating current, in the chronological mean value, contact resistance between the powder grains of the inversely the same size as the floating voltage of the gallium arsenide adds up to a very high resistance thermo electric generator. Both voltages rise in the amount. These contact resistances, however, are also centre and the current through the alternating current 10 very strongly dependent on the voltage or more accu circuit is a pure reactive current restricted by the reac rately on the electrical field strength between the pow tance of the capacitor 4, if all the other resistances and der grains. Since the currents 11 and 12 owe their losses of the circuit relative to the internal resistance of origin to a very high voltage, there are between the the thermo-electric generator can be neglected. If the gallium arsenide powder grains at the start of each half effective voltage of the alternating current source 3 is wave of the alternating current 11 and 12 very high reduced to 220 volts, then the effective current in the field strengths for a short time, which make the contact alternating current circuit falls back to 10 amperes.
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