MXPA99007213A - Method and apparatus for compensating a line synchronous generator - Google Patents

Abstract

A line synchronous generator with an exciter and generator stage. The exciter stage includes an exciter stator (28) and an exciter rotor (32), and the generator stage includes a generator stator (26) and generator rotor (34). In one embodiment, the stators are wound with primary windings for connection to an AC power source and the rotors are wound with secondary windings (Figure 2). In an alternative embodiment, the rotors are wound with primary windings for connection to the AC power source and the stators are wound with secondary windings (Figure 3). The proper phase angle alignment of the secondary windings are determined by connecting the primary windings of the exciter and generator stages to the AC power source, and connecting a secondary winding of the exciter stage to a secondary winding of the generator stage. The remaining open secondary leads are then tested for two pairs having a voltage equal to two times the line voltage, and two pairs having a voltage equal tov3 times the line voltage. The two pairs of open secondary leads having a voltage equal to two times the line voltage are connected together.

Description

METHOD AND APPARATUS TO COMPENSATE A SYNCHRONIC GENERATOR IN LINE FIELD OF THE INVENTION The present invention relates generally to an electric generator, and more particularly, to an improved induction generator relating to an AC power source.

BACKGROUND OF THE INVENTION Recently, because of the lack of fossil fuel and the ecological consequences of such use, several proposals have been invented to insert locally generated electric power into a public service grid. A variety of renewable fuel sources have been investigated. The ideal alternate energy fuel source will not have an adverse impact on the ecology and will result in a high grade fuel at a low cost. Common examples of alternate energy fuel sources are wind, hydroelectric, hydrocarbon gas recovery, solar, geothermal and waste heat recovery. Each of these fuel sources can be combined with electric power generators.

Ref. 031038 The difficulty in using these fuel sources lies in the quality of the fuel itself. For example, variations in wind speed severely limit the utility of wind power machines as a fixed and constant fuel source for a conventional induction or synchronous generator. This is because conventional generators can transmit a usable energy only when operating within a particular speed range. As a result, wind power machines must use AC generators wound in duplicate, or complex helix step control systems and mechanical drive systems that provide an appropriate generator speed. It is of practical use, however, that dual feed systems must provide proper rotor excitation and maintain the stator voltage constant, which is not easily accomplished. Where high-speed geothermal turbines or low-speed hydraulic turbines are used, speed, reduction, or elevation control devices must be used to provide the appropriate rotating speed for AC generation. The efficiency losses that accompany these types of mechanical conversion devices make up their economic viability and make them generally inadequate as sources of energy.

The compensation provided by these mechanical conversion systems is essential, however, because the insertion of locally generated electric power into a public service grid requires an exact phase and frequency equalization. Accordingly, if a device can be self-synchronizing and rotationally variable tolerant widely variable, the use of alternate fuel sources as means for the generation of electricity would be greatly increased. A notable example of such an automatic synchronization rotating device can be found in several patents published by Leo Nickoladze, specifically in U.S. Pat. 4,701,691 and 4,229,689, which are expressly incorporated herein by reference as if they were fully disclosed. 15 These last examples depend on the cancellation Electrical C within the inductive device itself, whereby all variations in the input energy are effectively eliminated. An exemplary modality of such The induction device is shown in Figure 1. The induction generator of Figure 1 includes two stages, an energizing stage 10 and a generating stage 12. The exciting stage 10 includes a driving stator 14 connected to an AC power source. 16 and an exciter rotor 18 placed for the Rotary advance by a local power source 19. The generating stage 12 includes a generator rotor 20, connected for the common rotation with the exciter rotor 18, and a generator stator 22. The windings of the excitadorld rotor and the generator rotor 20 are connected one with another, but they roll in opposite directions. The generator stator 22 is connected to a load 23.

In operation, the exciter rotor 18 is rotated by the local energy source 19 within the rotating magnetic field developed by the excitation stator 14. The frequency of the signal induced at the output of the exciter rotor 18 is equal to the sum of the proportion angle of the local power source 19 plus the frequency of the AC power source 16. Since the generator rotor 20 is rotated within the generator stator 22, the inverse connection to the exciter rotor 14 causes the angular ratio produced by the local energy source 19 that is subtracted. The result is an induced voltage at the output of the generation stator 22 equal in proportion to the frequency of the AC power source.

While the Nickoladze solution mentioned above provides a theoretical output voltage where only the line frequency of the service grid is produced, in practice, the manufacture of these devices is frequently fraught with difficulty for three phase power applications due to the alignment of the appropriate phase angle between the exciter and generator stages and the windings. Frequently, due to the physical windings of the rotor and stator elements, alignment of the phase angle between the energizing and generating stages could not be achieved in the past. In addition, some fully functioning devices simply fail, because the phase sequence of the windings is improper. These problems become even more pronounced when the exciter stage and the generating stage are manufactured independently of one another.

Accordingly, there is a current need for a three-phase synchronous line generator that can be produced with an adequate phase angle alignment for three phase power applications resulting in a constant frequency and a voltage output at shaft speeds variables It is desirable that the alignment of the phase angle be achieved easily, even for the components of the exciter and generator winding in opposite directions or with phases starting in different grooves on the core relative to the positioning slot.

BRIEF DESCRIPTION OF THE INVENTION One embodiment of the present invention relates to a method and apparatus that meets this need. Therefore, according to a preferred embodiment, a line synchronous generator having an exciter stage with a driving stator and a driving rotor, and a generating stage with a generating stator and a generating rotor is provided. In one embodiment, the stators are wound with primary windings for connection to an AC power source and the rotors are wound with secondary windings. In an alternative embodiment, the rotors are wound with primary windings for connection to the AC power source and the stators are wound with secondary windings.

The proper phase angle alignment of the first, second and third phase windings of the secondary windings is determined by connecting the primary windings of the driving and generating stages to the AC power source having a line voltage Vm, and connecting the first secondary phase winding of the exciter stage to the first secondary phase winding of the generating stage. Then, the voltage between the second secondary phase winding of the driving stage and the second secondary phase winding of the generating stage is confirmed to be approximately 2 Vm, and the voltage between the third secondary phase winding of the driving stage and the third secondary phase winding of the generating stage is confirmed to be approximately 2 Vm. Preferably, the voltage between the second secondary phase winding of the driving stage and the third secondary phase winding of the generating stage is confirmed to be approximately "V3 Vm, and the voltage between the third secondary phase winding of the stage The secondary phase winding of the generating stage is confirmed to be approximately 3 Vm. Once these voltages are confirmed, the second secondary phase winding of the driving stage is connected to the second secondary phase winding of the generating stage. , and the third secondary phase winding of the driving stage is connected to the third secondary phase winding of the generating stage.

In a preferred embodiment of a primary rotor machine, the line synchronous generator is configured with an exciter rotor positioned for rotary feed by an external power source. The exciter rotor includes a pair of poles, each having a winding for the connection through the AC power source. The exciter stator, mounted for rotation on an inner portion of the exciter stator, also has a pair of poles, each having a winding. The generator rotor, mounted for the common rotation with the exciter rotor, has a pair of poles, each having a winding for the connection through the AC power source. The generator stator has an inner portion with a generator rotor rotatably mounted therein. The generator stator has a pair of poles, each having a winding connected inversely to the corresponding windings in the pole pair of the exciter for the cancellation of the electric frequency induced by the rotation of the exciter and rotors. ^ generator. 5 An attractive feature of the described modes is that the line synchronous generator remains self-synchronizing despite variations in shaft speeds. In addition, the proper phase angle alignment can be easily achieved, even for the exciter and generator components independently manufactured with windings in opposite directions or with phases starting in different slots in the core relative to the positioning slot. This economically viable solution for 15 alternate energy sources has a greater potential to solve the present lack of energy with minimal adverse ecological consequences.

It is understood that other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein only embodiments of the invention are shown and described by way of illustration of the best modes contemplated for carrying out the invention. As will be realized, the invention is susceptible to other and different modalities and its various details are susceptible to modification in different respects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and the detailed description are contemplated as illustrative and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects, and advantages of the present invention will become better understood with respect to the following description, amended claims, and accompanying drawings where: Figure 1 is a simplified schematic illustration of an induction generator described in U.S. Pat. 4,701,691 and 4,229,689; Figure 2 is a simplified schematic illustration of a three phase stator primary line synchronous generator according to a preferred embodiment of the present invention; Figure 3 is a simplified schematic illustration of a three-phase rotor primary line synchronous generator according to a preferred embodiment of the present invention; Figure 4 is a simplified schematic illustration of a structure of the redundant line synchronous generator according to a preferred embodiment of the present invention; Figures 5A-5C are vector diagrams illustrating the appropriate phase relationships between the secondary windings of the line synchronous generator according to a preferred embodiment of the present invention; FIGS. 6A-6F are vector diagrams illustrating the appropriate phase relationships between the secondary windings of the line synchronous generator according to a preferred embodiment of the present invention.

Figure 7A is a schematic illustration showing the secondary windings of the line synchronous generator according to a preferred embodiment of the present invention before the test; Figure 7B is a schematic illustration showing the secondary windings of the line synchronous generator in accordance with a preferred embodiment of the present invention when properly connecting with compensated terminals; Figure 8 is a schematic illustration showing a compensation circuit system between the secondary windings according to a preferred embodiment of the present invention; Figure 9 is a graph illustrating the output energy for different compensation circuits as a function of the angular rotation of the rotors according to a preferred embodiment of the present invention; Figure 10 is a graph illustrating the output energy for phase angles between the driving and generating stage as a function of the angular rotation of the rotors according to a preferred embodiment of the present invention; Y Figure 11 is a vector diagram illustrating the appropriate phase relationships between the secondary windings of the line synchronous generator with a phase angle error of 15 ° according to a preferred embodiment of the present invention.

DETAILED DESCRIPTION A preferred embodiment of the present invention is > shown in Figure 2. The synchronous three-phase line generator includes two stages, an energizing stage 24 and a generating stage 26. The exciting stage 24 includes a driving stator 28 having three pairs of electromagnetic pole. Each pole pair has a primary winding connected through a different phase of an AC power source 30. A rotor | 10 exciter 32, mounted for rotation within the interior of the exciter stator 28, also includes three pairs of electromagnetic pole , each wound with a secondary winding. The exciter rotor 32 is placed for rotary feed by a local power source 33. The generating stage 26 includes a generator rotor 34 connected for common rotation with the exciter rotor 32 within the interior of a generator stator 38. The generator rotor 34 also includes three pairs of polo electromagnetic, each wound with a secondary winding. The secondary windings of the generator rotor are inversely connected to the secondary windings of the exciter rotor 32 to effect the electrical cancellation of the frequency induced by the angular rotation of the local energy source. He The generator stator 38 is connected to the AC power source 30.

In an alternative embodiment of the present invention, the rotors of the driving and generating stages are connected to the AC power source, and the three-phase windings of the exciter and generator stators are connected for electrical cancellation. Turning to Figure 3, a driving rotor 52, positioned for rotary feed by a local power source 53, has three pairs of electromagnetic pole, each with a primary winding connected through a different phase of the electromagnetic pole pairs. windings with secondary windings.

Similarly, the generating stage 64 includes a generator stator 74 with three electromagnetic pole pairs wound with secondary windings. The secondary windings of the exciter stator 72 are inversely connected to the secondary windings of the generator stator 74 to effect the electrical cancellation of the frequency induced by the angular rotation of the local power source. The generator rotor 75, connected for the common rotation with the exciter rotor 52, is connected to the AC power source 54. For explanatory purposes only, the embodiments of the present invention will be described for a three-phase synchronous line generator configured as a stator primary machine, that is, the stators are connected to the AC power source. However, it will be understood by those skilled in the art that the present invention is not limited to stator primary machines, and that all described modes and test procedures are equally applicable to primary rotor machines, i.e. rotors are connected to the AC power source.

As shown in Figure 4, the line synchronous generator can be enlarged to include redundant components.

Specifically, a third redundant stage comprising a rotor 78 on the common shaft 80 and a stator 76 can be left disconnected. Then the terminals T001, T002 and T003 can be connected in the reset by the terminals TI, T2 and T3 or T101, T102 and T103, in case the exciter or generator stage fails.

The operation of the generator is described with reference to Figure 2. With stator primary machines, the exciter stator 28 is excited by the AC power source 30, which creates a rotating magnetic field at an angular ratio equal to the frequency of the AC power source 30. The exciter rotor is rotated by the local power source 33 within the rotating magnetic field developed by the exciter rotor 28. The frequency of the signal induced at the output of the exciter rotor 32 is equal to the sum of the angular ratio of the local power source 33 plus the frequency of the AC power source. Since the generator rotor 34 is rotated within the generator stator 38, the inverse connection to the exciter rotor 32 causes the angular ratio produced by the source of local energy to be subtracted 33. The result is an induced voltage at the stator output of generation 38 equal in proportion to the frequency of the AC power source. Thus, at any angular ratio higher than the synchronous speed for a multi-pin generator according to one embodiment of the present invention, the voltage output will have the same frequency, since the source is switched on. Below the synchronous speed, energy will be consumed rather than generated.

While this theoretical solution solves the effects of variations in shaft speed on the output frequency of a three-phase line synchronous generator, optimal output operation can be achieved only by proper alignment of phasing between the energizing stages and generator 24 and 26. This connection is achieved by initially ensuring that the primary windings of the driving stage have the same sequence of phases as the primary windings of the generating stage, and then inversely connecting the secondary windings of the driving and generating stages.

As a result of the exciter and generator stages being manufactured independently of one another, it is important to determine the proper connection between the primaries to ensure that each stage of the line synchronous generator has the same phase sequence. This determination can be made in a number of ways. For example, with a stator primary machine, a small three-phase motor can be operated from the stator windings with power supplied to the rotor windings. The appropriate staging sequence of the stator windings will be presented when the motor is driven in the same direction of rotation of both the stator exciter winding and the stator generator winding. Another way to obtain the proper phase sequence is with a phase rotation meter, or with two lamps and an AC capacitor connected in and in accordance with the test techniques known in the art.

Once the proper phase sequence is established, the stator windings are connected to the corresponding phases of the AC power source. Then the proper phase angle between the rotor windings is established by the interconnection process. To obtain the electrical cancellation of the frequency induced by the angular ratio of the rotor axis, the rotor windings must be connected in such a way that the voltage induced by the angular rotation in each rotor winding exciter has an equal, but opposite polarity that the induced voltage in the generator rotor winding to which it is connected.

The vector diagrams provide a useful mechanism to illustrate how the interconnections between the second windings can be ascertained. As shown in Figures 5 and 6, only three possible interconnections between the rotor windings results in a 180 ° phase shift between each secondary winding connection as shown in Figures 5A-5C, each rotary exciter winding moves 180 ° with respect to its rotor winding generator correspondent. For example, consider Figure 5B. The following phase angles between the connected terminals are easily ascertained: T03 = 0o and T3 = 180 °; ? 180 ° T01 = 120 ° and TI = 300 °; ? 180 °, and T02 = 240 ° and T2 = 60 °; ? 180 °.

The same phase relationships are maintained exactly for the secondary connections shown by the vector diagrams in Figures 5A and 5C.

By contrast, there are six different possible interconnections, which will not effect the electrical cancellation of the frequency induced by the angular rotation of the rotors. These six incorrect connections are shown by the vector diagram in Figures 6A-6F. As shown in each of these diagrams, the voltages in each pair of connections between the exciter rotor and the generator rotor do not only have the same voltage, but have the same phase. Referring to Figure 6A, by way of example, this relationship is easily shown uncle: T01 = 300 ° and TI = 300 °; ? 0o T02 = 60 ° and T2 = 60 °; ? 0o; and T03 = 180 ° and T3 = 180 °; ? 0o. 15 These vector diagrams are also useful for establishing the test parameters to determine the proper interconnections between the rotor windings during the manufacturing process. Common to each of the diagrams vectors of Figures 5A-5C, with a rotor rotor winding of the three-phase windings connected to a generator rotor winding, the voltages between the remaining open windings will consist of two pairs at two times the line voltage (2 Vm) and two pairs at 3 times the line voltage (3 Vm), which is demonstrated by the geometric relationship between the phases. For example, the voltages induced in the open windings in Figure 5B are: T2 to T02 2 Vm T3 to T03 2 Vm T2 to T03 = 3 Vm T3 to T02 = 3 Vm Since the vectors have a designated length and the direction in space, these results can be verified with an ordinary rule.

Vector diagrams can be confirmed mathematically. Classical electrical theory holds that when a voltage is applied to a primary winding of an induction generator, a voltage will be induced in the secondary open-circuit winding. A three-phase winding connected in and has each phase displaced by 120 °. The voltage induced in the open circuit secondary terminals will be balanced. For the stress test, a jumper wire interconnects a terminal of each secondary winding. In Figure 5B, this is the terminal TI and terminal T01. With a voltage applied to the primary, the remaining open-circuit secondary voltages are measured. For Figure 5A, this would be T2 up to T02 T3 up to T03 T2 up to T03 T3 up to T02 As can be easily seen from Figure 5A, the secondary voltage between T2-T01 is the line voltage. Also, the voltage between T1-T02 is the line voltage. Therefore, the voltage between T2-T02 will be twice the line voltage. The same holds exactly for T3-T03.

The voltage across T2-T03 is the resultant of an oblique-angled triangle defined by the sides T1-T03, T01-T2 and T2-T03. When the classical three-phase electric theory, properly aligned, identifies the angles as shown in Figure 5B. The resulting voltage between T2-T03 will be: Sen ^ B ^ 2-03 ~ V2-03 / sin < -_ For the proper alignment: V2-03 = (2-03) (s eno 120 ° / sine 30 °) (V 2-03) (0 .866 / 0. 5) = (V2_03) (1.73) The same holds exactly for the voltage between T3-T02. Therefore, with proper alignment, the voltage will be a pair of terminals at twice the line voltage and a pair of terminals at "V3 times the line voltage.

With the knowledge obtained from these vector diagrams, we can find out an interconnection methodology of the rotor windings, which significantly reduce the manufacturing cost, while increasing the yield of the product. Specifically, the method for determining suitable interconnections in a stator primary machine requires the connection of a pair of rotor windings and then finding two remaining pairs of identical voltages substantially between the rotor windings.

Returning to Figure 7A, the secondary windings are shown ready for testing. The exciter and generator stators are connected to an AC power source. The induced line voltages should be the same if the two groups of rotor windings are similar: speed, pitch, wire size, connection, etc. In this example, the interface voltage is 90 volts. The connection could be in ye (star) as shown, or delta, or one of each. To obtain the test readings, one terminal of each rotor winding is connected by a connecting bridge.

Either the primary or secondary could be the rotor or stator, but they must be the same part. In this way, if one half of the synchronous generator is configured as a primary rotor machine, then the other half of the synchronous generator must also be configured as a primary rotor machine.

As defined by the vector diagrams of Figures 5 and 6, two pairs of substantially identical voltages must be found. With a line voltage of 90 volts, the following values must be obtained during the test: 2 (90) = 180 volts for a voltage pair; and "V3 (90) = 156 volts for the other voltage pair.

To carry out the test, a jumper wire is placed through a terminal for each rotor winding. In this example, a bridge wire is first placed through TI and T01 and the following voltages are obtained by test: T2 - T02 = 156 volts T2 - T03 = 90 vlts T3 - T02 = 180 volts T3 - T03 _ 156 volts These measured voltages are consistent with Figures 6A-6F showing the improper interconnection of the rotor windings.

Then the bridge wire is removed and placed through another terminal pair. In this example, the bridge wire is then placed through T2 and TO1, and the following voltages are obtained by test: TI - T02 = 156 volts TI - T03 = 180 volts T3 - T02 = 180 volts T3 T03 156 volts This result is consistent with Figures 5A-5C and confirms the proper interconnection of the rotor windings. From the vector diagrams 5A-5C it can be seen that rotor windings having a voltage of 2 Vm, or 180 volts should be connected to each other. The appropriate interconnections of the rotor windings are shown in Figure 7B with TI connected to T03 and T3 connected to T02. Preferably, the terminals should be renumbered.

Once the proper phase angle is established between the rotor windings, the electrical compensation can then be inserted between each pair of the three phase windings. Specifically, the resistors and capacitors can be inserted between the respective windings to extend the range of dynamic operation of the device without the need for continuous phase angle adjustments between the energizing and generating stages. Alternatively, electrical compensation can be inserted into the primary windings of the stators.

Returning to Figure 8, the effect of the compensation resistance inserted between the rotor windings results in an extended operating range that allows a higher operating speed. In this example, the compensation networks 76, 78 and 80 effect the winding interconnection described above. The network 76 includes a resistor 82, in parallel with a capacitor 84, the network 78 comprises a resistor 88 in parallel connection with a capacitor 90, and the network 80 comprises a resistor 94, in parallel connection with a capacitor 96. It has been found that by increasing the resistance of the resistors 82, 88, and 94 from about 0 ohms to about 5.8 ohms, the dynamic range expressed in proportion of both the energy factor and efficiency increases substantially.

Figure 9 shows the extended range of the device using utilization resistors to achieve the desired results for the adapted applications. The output curve is shown for a 3-phase, 15-k, 4-pole, 60-Hz line synchronization generator.

Another important parameter for optimizing the operation of the three-phase synchronous line generator is the phase angle between the generating and driving stages. In a preferred embodiment of the present invention, the angular position of the eccitator stator, exciter generator, generator rotor or generator stator can be advanced or delayed to optimize operation. The optimal load is a function of the exciter phase angle and the rotor rpm. Since the RPMs increase substantially above the "synchronous speed", the range of the necessary phase angle that complies with the maximum generator load is significantly limited. In this way, through the manipulation of the phase angle of the driving stage in relation to the generating stage, complete control over the load is achieved. An accurate and responsive device must be employed to adequately provide an optimization of the phase angle when using variable speed primary motors.

Figure 10 illustrates the output power of a 6-pole, 25-k, 480-volt, 60-Hz stator primary machine attached to a variable-speed DC motor with 75 horsepower at different phase angles. The energy output is shown at four different phase angles between the magnetic field of the exciter and generator.

In a preferred embodiment, the field of the generator state is designated and compared to the frequency of the AC source by a control mechanism to provide a signal of the phase error to a servomotor. This servomotor places the exciter stator in a convenient position to optimize the generator load, a function of the phase difference that results from changes in shaft speed. The accuracy and response of the servomotor and its control mechanism are critical to optimize the generator load. Because the control technology for the servomotor is sufficiently advanced, the exciter compensation of the exact exciter can be provided in virtually all electric power generation applications.

Alternatively, the phase angle can be set during the interconnection process of the rotor windings. Turning to Figure 11, a vector diagram is shown that represents the phase relationships of the rotor windings with adequate interconnection to effect electrical cancellation, but with a misalignment of the phase angle of 15 ° between the energizing and generating stages. The test represented in Figure 10 is carried out with IT connected to TOl. The following test results are obtained: T2 up to T02 178 bolts T2 up to T03 143 volts T3 up to T02 166 volts T3 up to T03 178 volts The voltage between terminals T2 - T02 and T3 - T03 are each of 178 volts, which is quite close to 180 volts to satisfy one of the required pairs. However, the voltages between the remaining terminals are not quite close to 156 volts to satisfy the second required torque. However, if the voltages are averaged, the result is 155 volts, which is close to the desired voltage. This indicates an improper phase angle between the driving stage and the generating stage. In this case, either the exciter stator, the exciter rotor, the generator stator or the generator rotor can be physically rotated about its axis until the voltage between T2 and T03 and the voltages between T3 and T02 each indicate 155 volts. In this case, from the vector diagram of Figure 8, it can be seen that an electric phase shift of 15 ° will result in optimal operation.

Alternatively, the correction of the phase angle can be carried out by altering the windings of either the exciter rotor, exciter stator, generator rotor or the stator generator. In other words, the optimum phase angle can be achieved without physically displacing the rotors or stators, but winding them out of alignment. If the slots in the generator portion are numbered from 1 to 36, for example, start the generator set in slot 1, and the exciter group starts in slot 2 or 3, to get the phase angle as shown you want The physical angular displacement is determined by the number of poles. Specifically, the angular displacement is: 360 ° __ "= • (Phases) x (Poles) For a three-phase system of four (4) poles this angle is: (3X4) Therefore, an angular displacement of 20 ° is required. This can be done by moving the winding of two fixed cores only if the number of slots allows it to be meet the necessary angle. For example, a core of 36 slots with a displacement of two slots would result in 20 ° and is acceptable for a three-phase system of four (4) poles. But a core of 48 slots does not result in any combination of 20 °, and therefore, the alignment of the phase angle '15 could not be obtained by the displacement of the core.

The described embodiments provide an important solution that allows the rotating speed to vary substantially over the limits of the traditional machinery, 20 while still being auto-synchronized. The active controls are simplified to those necessary for security purposes. The maximum speed limits of the machinery can be increased with a simple active control of passive devices. This shows the versatility of the inventor, an inherently acceptable speed range which can be enlarged by the addition of simple passive devices. In this way, any source of local energy which produces a minimum velocity and exceeds the parasitic losses of the device can be effectively used to supply the service grid. Such adaptation of local alternative energy sources has a greater potential to solve the present lack of energy with minimal adverse ecological consequences.

It is apparent from the foregoing that the present invention satisfies an immediate need for a three-phase synchronous line generator with suitable throttling having a constant frequency and a voltage output at variable shaft speeds. This three-phase synchronous line generator can be included in other specific forms and can be used with a variety of fuel sources, such as windmills, wind turbines, water wheels, hydraulic turbines, internal combustion engines, engines powered by sunlight, steam turbine, without departing from the spirit or essential attributes of the present invention. Therefore, it is desired that the described embodiments be considered in all respects as illustrative and not restrictive, reference is made to the amended claims rather than to the description mentioned above to indicate the scope of the invention.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Having described the invention as above, the content of the following is claimed as property.

Claims (9)

1. A method for determining the proper phase alignment of a three-phase line synchronous generator, the line synchronous generator comprises an exciter stage having a driving stator and a driving rotor, a driving stator and driving rotor having a primary winding and the other exciter stator and exciter rotor has a first, second and third secondary phase windings, and a generating stage having a generator rotor and a stator generator, one stator generator and rotor generator has a primary winding and the other stator winding generator and rotor generator has a first, second and third secondary phase windings, characterized in that the method comprises the steps of: connecting the primary windings of the exciter and generator stages to a three-phase AC power source, the AC power source has a line voltage equal to Vm; connecting the first secondary phase winding of the driving stage to the first secondary phase winding of the generating stage; confirming a voltage between the second secondary phase winding of the driving stage and the second secondary phase winding of the generating stage equal to about 2 Vm; confirming a voltage between the third secondary phase winding of the driving stage and the third secondary phase winding of the generating stage equal to about 2 Vm; Y connecting the second secondary phase winding of the driving stage to the second secondary phase winding of the generating stage; connecting the third secondary phase winding of the driving stage to the third secondary phase winding of the generating stage.

2. The method according to claim 1, characterized in that it further comprises the steps of confirming a voltage between the second secondary phase winding of the driving stage and the third secondary phase winding of the generating stage equal to approximately "V3 Vm, and confirming a voltage between the third phase winding secondary to the exciter stage and the second secondary phase winding of the generating stage equal to approximately ^ 3 Vm.

3. The method according to claim 1, characterized in that the secondary windings of the exciter stage are wound on the exciter rotor, and the secondary windings of the generating stage are wound on the generator rotor.

4. The method according to claim 1, characterized in that the secondary windings of the driving stage are wound on the excitation stator, and the secondary windings of the generating stage are wound on the generating stator.

5. The method according to claim 1, characterized in that it further comprises the step of rotating one of the exciter stator, exciter rotor, generator stator and generator rotor on its axis before confirming the voltage between the second secondary phase winding of the exciter stage. and the second secondary phase winding of the generating stage and confirming the voltage between the third secondary phase winding of the driving stage and the third secondary phase winding of the generating stage.

6. The method according to claim 1, characterized in that it also comprises the step of confirming the same sequence of phases in the primary windings of the driving and generating stages.

1 . A synchronous line generator, characterized in that it comprises - a exciter rotor, placed for the rotary advance by an external energy source, comprising a pair of poles, each having a winding for the connection through a power source of AC; an excitation stator having a pair of poles, each having a winding, the exciter rotor is mounted for rotation on an inner portion of the exciter stator; a generator rotor mounted for common rotation with the exciter rotor; the generator rotor has a pair of poles, each has a winding for the connection through the AC power source; Y a generator stator having an inner portion with the generator rotor rotatably mounted therein, the generator rotor having a pair of poles, each having a winding connected inversely to the corresponding windings in the pole pair of the exciter for cancellation of a Electrical frequency induced by the rotation of the exciter and generator rotors.

8. The line synchronous generator according to claim 7, characterized in that each of the exciter and generator rotors comprises three pairs of poles with a three-phase winding for connection to a three-phase AC power source, and each of the exciter and generator stators comprises three pairs of poles with a three-phase winding, the three-phase winding of the exciter stator is inversely connected to the three-phase winding of the generator stator for the cancellation of the electrical frequency induced by the rotation of the exciter and generator rotors.

9. In addition, it comprises a redundant rotor connected for the common rotation with the exciter and stator rotors, and a redundant stator having an inner portion with the redundant rotor rotatably mounted therein, The redundant stator has a pair of poles, each one has a winding adapted for the inverse connection to one of stator exciter and generator stator.