Transient impedance transformer based on AC voltage regulating electronic switch

Abstract

A superposition principle of waveform based on conceptions of waveform continuity and flexible regulation of voltage proposes three concepts, respectively being flexible AC transformation, flexible power transmission and transformation and flexible voltage regulation; proposes three new technologies, respectively being a transient impedance technology, a flexible stepless voltage regulation technology and a flexible stepped voltage regulation technology; proposes three new products, being an AC voltage regulating electronic switch, a transient impedance transformer and a high-speed voltage regulating transformer; proposes six high-voltage power grid connection methods, being a power grid connection method type of a transient impedance transformer, a power grid connection method of a transient impedance step up auto transformer and the like; and proposes a new reactive compensation connection method for a reactive compensation device.

Claims

1. A series voltage regulating transformer, comprising: a main transformer portion including a first primary winding, a voltage regulating winding, and one or more first secondary windings, and a series transformer portion including a second primary winding and one or more second secondary windings, wherein, each of the first primary winding or the first secondary winding is connected, in series, to each of the second secondary windings, respectively, and the voltage regulating winding is connected to the second primary winding, and wherein the output voltage of the series voltage regulating transformer is equal to a voltage of the first primary winding or the first secondary winding of the main transformer portion plus or minus a voltage of the second secondary winding of the series transformer portion, which second secondary winding is connected, in series, to the first primary winding or the first secondary winding.

2. The series voltage regulating transformer of claim 1, wherein the first primary winding and the first secondary winding are connected in a self-coupling manner.

3. The series voltage regulating transformer of claim 1, wherein the series voltage regulating transformer further comprises a reactive compensation device, the reactive compensation device is connected, in series or parallel, to the voltage regulating winding or the second primary winding of the series transformer portion.

4. A transient impedance transformer, comprising: a series voltage regulating transformer; and an AC voltage regulating electronic switch, wherein the series voltage regulating transformer comprises a main transformer portion including a first primary winding, a voltage regulating winding, and one or more first secondary windings, and a series transformer portion including a second primary winding and one or more second secondary windings, the AC voltage regulating electronic switch comprises one or a plurality of sub switches, each of which is an AC switch; and one or a plurality of voltage regulating power sources, every two of the sub switches are connected with each other by one of the voltage regulating power sources, respectively, wherein an output voltage of the AC voltage regulating electronic switch is controlled by a voltage regulated by the voltage regulating power source, wherein, each of the first primary winding or the first secondary winding is connected, in series, to each of the second secondary windings, respectively, and the voltage regulating winding is connected to the second primary winding, wherein an output voltage of the series voltage regulating transformer is equal to a voltage of the first primary winding or the first secondary winding of the main transformer portion plus or minus a voltage of the second secondary winding of the series transformer portion, which second secondary winding is connected, in series, to the first primary winding or the first secondary winding, and wherein the AC voltage regulating electronic switch is connected to the voltage regulating winding or the second primary winding.

5. The transient impedance transformer of claim 4, wherein the first primary winding and the first secondary winding are connected in a self-coupling manner.

6. The transient impedance transformer of claim 4, wherein the AC switch is comprised of two semiconductor elements which are connected in anti-parallel.

7. The transient impedance transformer of claim 4, wherein the AC voltage regulating electronic switch further comprises a constant voltage power source, wherein, a first terminal of the constant voltage power source is connected to an input terminal of the AC voltage regulating electronic switch, a second terminal of the constant voltage power source is connected to a circuit constituted by the sub switch and the voltage regulating power source, and the output terminal of the circuit constituted by the sub switch and the voltage regulating power source is connected to the output terminal of the AC voltage regulating electronic switch, and wherein, the output voltage of the AC voltage regulating electronic switch is equal to a voltage of the constant voltage regulating power source plus or minus a voltage regulated by the voltage regulating power source.

8. The transient impedance transformer of claim 7, wherein, first terminals of each of the sub switches are connected with each other, second terminals of every two of the sub switches are connected with each other by one of the voltage regulating power sources, respectively, and a second terminal of the constant voltage power source is connected to a second terminal of a first sub switch among the plurality of sub switches.

9. The transient impedance transformer of claim 7, wherein the AC voltage regulating electronic switch further comprises another first sub switch and another second sub switch, wherein first terminals of each of the sub switches are connected with each other, and second terminals of every two of the sub switches are connected with each other by one of the voltage regulating power sources, respectively, wherein, a first terminal of the another first sub switch is connected to a second terminal of the first sub switch of the plurality of sub switches, and a second terminal of the another second sub switch is connected to a second terminal a last sub switch of the plurality of sub switches, and wherein, a second terminal of the constant voltage power source is connected to a second terminal of the another first sub switch and a first terminal of the another second sub switch.

10. The transient impedance transformer of claim 7, wherein a second terminal of the constant voltage power source is connected to the second terminal of the first sub switch of the plurality of sub switches, wherein, the plurality of sub switches include a first group of sub switches and a second group of sub switches, first terminals of each sub switch of the first group of sub switches are connected with each other, second terminals of every two of the first group of sub switches are connected by one of the voltage regulating power sources, respectively, first terminals of the second group of sub switches are connected with each other, and second terminals of every two of the second group of sub switches are connected by one of the voltage regulating power sources, respectively, and wherein, a first terminal of the last sub switch of the first group of sub switches is connected to a second terminal of the first sub switch of the second group of sub switches.

11. The transient impedance transformer of claim 10, further comprising another constant voltage power source, Wherein, a first terminal of the another constant voltage power source is connected to the first terminal of the last sub switch of the plurality of sub switches, and a second terminal of the another constant voltage power source is connected to the output terminal of the AC voltage regulating electronic switch.

12. The transient impedance transformer of claim 7, further comprising another constant voltage power source, wherein first terminals of each of the sub switches are connected with each other, and second terminals of every two of the sub switches are connected with each other by one of the voltage regulating power sources, respectively, wherein a second terminal of the constant voltage power source is connected to the first terminal of the first sub switch of the plurality of sub switches, and a first terminal of the another constant voltage power source is connected to the second terminal of the last sub switch of the plurality of sub switches, and wherein the second terminal of the another constant voltage power source is connected to the output terminal of the AC voltage regulating electronic switch.

13. The transient impedance transformer of claim 4, wherein the series voltage regulating transformer further comprises a reactive compensation device, the reactive compensation device is connected, in series or parallel, to the voltage regulating winding or the second primary winding of the series transformer portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram showing the principle of a new AC voltage regulator.

(2) FIG. 2 is a schematic diagram showing the principle of a linear regulating AC voltage regulating electronic switch.

(3) FIG. 3 is a schematic diagram showing the principle of a reversing change-over AC voltage regulating electronic switch.

(4) FIG. 4 is a schematic diagram showing the principle of a coarse-fine regulating AC voltage regulating electronic switch.

(5) FIG. 5 is a schematic diagram showing the principle of an intermediate regulating AC voltage regulating electronic switch.

(6) FIG. 6 is a schematic diagram showing the principle of an intermediate regulating AC voltage regulating electronic switch.

(7) FIG. 7 is a schematic diagram showing the principle of an end portion regulating AC voltage regulating electronic switch.

(8) FIG. 8 is a schematic diagram showing the principle of a neutral point regulating AC voltage regulating electronic switch.

(9) FIG. 9 is a schematic diagram showing the principle of a measuring and control device.

(10) FIG. 10 is a schematic diagram showing the principle of a splayed coil structure.

(11) FIG. 11 is a schematic diagram showing the principle of a single phase series voltage regulating transformer (one of which is showed, the rest are omitted).

(12) FIG. 12 is a structure diagram showing the principle of tertiary side disconnection (the schematic diagram of location of the two compensation method, only one of which is need in compensation).

(13) FIG. 13 is a schematic diagram showing the principle of a high-speed voltage regulation special auto transformer.

(14) FIG. 14 is a schematic diagram showing the principle of a power grid connection method type of a transient impedance step up auto transformer.

(15) FIG. 15 is a schematic diagram showing the principle of a series voltage regulating transformer phase controlled by an AC voltage regulator.

(16) FIG. 16 is a schematic diagram showing the principle of a transient impedance furnace transformer.

(17) FIG. 17 is a vectogram showing the current before compensation.

(18) FIG. 18 is a vectogram showing the current after compensation.

(19) Wherein: 1. constant voltage power source (or sine wave power source); 2. AC voltage regulator; 3. primary winding of a new AC voltage regulator; 4. secondary winding of a new AC voltage regulator; 5. basic coil; 6. voltage regulation coil; 7. AC voltage regulating electronic switch; 8. reversing change-over AC voltage regulating electronic switch; 9. coarse regulating AC voltage regulating electronic switch; 10. fine regulating AC voltage regulating electronic switch; 11. structure of secondary winding of main transformer of series voltage regulating transformer of splayed coil; 12. structure of secondary winding of series transformer of series voltage regulating transformer of splayed coil; 13. series voltage regulating transformer voltage regulation coil; 14. primary coil of the main transformer of the series voltage regulating transformer; 15. secondary coil of the main transformer of the series voltage regulating transformer; 16. portions not showed by coils; 17. primary coil of the series transformer of the series voltage regulating transformer; 18. secondary coil of the series transformer of the series voltage regulating transformer; 19. power grid; 20. load; 21. power grid; 22. schematic diagram showing locations for reactive compensation; 23. basic winding for tertiary side disconnection; 24. short circuit switch; 25. tertiary side load circuitry breaker.

(20) The above figures are illustrated in single phase, and the three phases is in a similar way. In principle, other connection methods and connection positions of the AC voltage regulator may be combined with the connection method of the transformer arbitrarily, which are not illustrated wholly.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Example 1

(21) In the present solution, the AC voltage regulating electronic switch is not used, but a new AC voltage regulator is used, which is aimed at showing the capability of voltage regulation of the AC voltage regulator under extreme cases. A furnace, resistance-inductive load, is provided, when the distance from the electrode to the burden surface is determined, the maximal and minimal output voltages of the series voltage regulating transformer is required to be between 1 and 0.7, respectively.

(22) A furnace transformer, three phases, is provided, and a series voltage regulating transformer, with range of voltage regulation of 30% and positive voltage regulation, is also provided, the main transformer and the series transformer are of an Yd11 connection group. The output constant voltage at lower voltage of the main transformer is U.sub.1=0.7, and the highest output voltage at lower voltage of the series transformer is U.sub.2=0.3. The high voltage and current of the series transformer can be combined arbitrarily, as long as the capacity thereof is equal to the capacity of the series transformer.

(23) An AC voltage regulator is provided, a three-phase AC voltage regulator is connected in a manner of Y, the voltage of the semiconductor is defined as the phase voltage of the tertiary side system multiplied by a correlation coefficient as defined in its specification, the current effective value is 2 or 3 times of the tertiary side current of the series voltage regulating transformer (determined by total impedances), the delay angle of the thyristors is defined as ?, the conduction angle of the thyristors is defined as ?, and the impedance angle of the system is defined as ?, and is activated by a broad pulse or pulse trains. The principle of the single-phase electrical wiring is showed in FIG. 15 (there is no reversing change-over switch in the present example), and the three-phase wiring graph is combined as Y and d11, the principle thereof is not illustrated herein.

(24) When the system needs the maximal voltage, the control angle of the thyristor ???, the output voltage of low voltage side of the transformer is U=U.sub.1+U.sub.2=0.7+0.3=1. When the system needs the lowest voltage, the control angle of the thyristor ?=180?, i.e., U.sub.2=0, and the output voltage of low voltage side of the transformer U=U.sub.1=0.7. When the system needs other voltage, the control angle of the thyristor ?=0, ????180?, and the output voltage of low voltage side of the transformer U=0.7?1.

Example 2

(25) A furnace transformer with range of voltage regulation of 40%, reversing change-over voltage regulating, Yd11 connection group, and a series voltage regulating transformer are provided. The secondary winding of the main transformer is connected, in parallel, to the capacitor group to adjust the power factor. Before compensation, cos ?=0.8, it is required that after compensation, cos ?=0.95. The principle of electrical wiring is showed by the combination form of the low-voltage winding and the reactive compensation device, as showed in FIG. 16. U.sub.21 and U.sub.22 are secondary voltages of the main transformer, and series transformer, respectively, and the leakage reactance of the transformer is omitted. FIG. 17 is a vectogram showing the current before compensation. Before compensation, the power factor is defined as cos ?=0.8, sin ?=0.6, and meanwhile, the working current of the furnace I.sub.L=1. The active component of the working current is I.sub.R=0.8. The idle component of the working current is I.sub.Q=0.6. Both the currents flowing through the secondary winding of the main transformer and the series transformer are working current I.sub.L of the furnace. FIG. 18 is a vectogram showing the current after compensation. As the compensation (capacitance) current only flow through the secondary winding of the main transformer, it is assumed that the vector angle between the magnitude of the current of the secondary winding of the main transformer after compensation and its voltage U.sub.21 will be changed.

(26) It is assumed that the working current of the furnace after compensation is still I.sub.L=1, and the power factor of the secondary winding of the main transformer after compensation is 0.95.

(27) The current in the secondary winding of the main transformer is changed to I.sub.21=0.842. The current flowing through the compensation capacitor is I.sub.C=0.3374. The secondary capacity of the main transformer after compensation is SN.sub.21=0.842 (it is assumed that the secondary voltage of the main transformer is U.sub.21=1). The decreased value of the secondary capacity of the main transformer after compensation is ?SN.sub.21=0.158. The capacity of the required compensation capacitor should be S.sub.C=0.3374.

(28) The electromagnetic capacity required by the secondary winding of the main transformer after compensation is about 84.2% of that before, and thus the capacity of the primary winding of the main transformer is decreased correspondingly. As the range of voltage regulation is 40%, and may be of a reversing change-over form, the capacity of the transformer before compensation is SN.sub.1.

(29) SN.sub.1capacity of the transformer before compensation. SN.sub.11capacity of the main transformer before compensation is 0.8SN.sub.1. SN.sub.12capacity of the series transformer before compensation is 0.2SN.sub.1. SN.sub.1=SN.sub.11+SN.sub.12=0.8SN.sub.1+0.2SN.sub.1. The capacity of the transformer after compensation is SN.sub.2the capacity of the transformer after compensation. SN.sub.21the capacity of the main transformer after compensation. SN.sub.22the capacity of the series transformer after compensation.
SN.sub.2=SN.sub.21+SN.sub.22=0.8SN.sub.1?0.842+0.2SN.sub.1=0.8736SN.sub.1

(30) It can be seen that, the capacity of the whole device after compensation is improved by about 12.5%, i.e., the active power is improved.

Example 3

(31) A furnace transformer with range of voltage regulation of 40%, reversing change-over voltage regulating, Yd11 connection group, and a series voltage regulating transformer are provided. The low voltage of the main transformer is 0.8, the low voltage of the series transformer is 0?0.2, the combined voltage of the main and series transformers is 0.8?(0?0.2), with 21 levels of voltage regulation, each of which is 0.02, the capacity of the main transformer is 0.4?1, and the tolerance of each level of the main transformer is 0.03. It is assumed that the ratio of transformation is 1, and the resistance values of the two windings of the low-voltage main and series transformers are the same. It is assumed that the working current of the furnace after compensation is still I.sub.L=1, and the current of the secondary winding of the main transformer is I.sub.21=0.842, and the no-load loss is about of 15% of the load loss.

(32) As showed in Example 2: loss of the transformer Pk is
Pk=(0.842I.sub.L).sup.2?0.8?R+(I.sub.L).sup.2?0.2?R=0.767(I.sub.L).sup.2?R

(33) That is, the energy conservation and consumption reduction of the load of the transformer is about 23%.

(34) As the no-load loss is about 15% of the load loss. The total loss ratio of the transformer after and before the regulation of the power factor is: (0.767 I.sub.L).sup.2R+0.15(I.sub.L).sup.2R)/1.15(I.sub.L).sup.2R=0.797(I.sub.L).sup.2R. That is, the total energy conservation and consumption reduction of the transformer is about 20%.

INDUSTRIAL UTILITY

(35) The application of the transient impedance technology and high-speed voltage regulation technology, high-speed stepless voltage regulation technology according to the present invention in a high voltage or ultra-high voltage AC-DC power transmissions system, an AC/DC furnace smelting system, an electrochemically electrolytic industry system, a electric power locomotive traction system, a reactive compensation system, and a high-power stepless voltage regulation is beneficial to safety protection and high efficiency synchronous intelligent control of the associated system.

(36) When the present invention is applied to resistive, resistive-inductive, and resistive-capacitive load systems requiring stable control, or requiring capacity regulation of the transformer, or requiring high-speed control of characteristics of each phase unbalanced load and other characteristics, the transient impedance transformer may be used to control its feature in a high speed.

(37) The present invention may be used to improve the stability and reliability of the high voltage or ultra-high voltage power system, reduce system short circuit capacity, reduce equipment investment, reduce voltage fluctuation and flickering, the high voltage circuitry breaker may be replaced by the tertiary side disconnection function, and the transformer has obvious effects of regulating system impedance in a high speed and improve the power factor of the system per se.

(38) The stepless voltage regulation has great breakthrough in capacity, voltage classes, waveform deviation factor and other aspects, and has great influence on the industry which has great requirements on stepless voltage regulation devices, such as, vacuum furnace, scientific experiment and the like.

(39) The stepless voltage regulation may be applied to fields of industrial and agricultural production, scientific experiment, communication and transportation, telecommunication transmission, national defense, health care, power transmission. So to speak, the transient impedance transformer plays a role in various industry of national economy.