Internal split field generator

A generator includes a coil of conductive material. A stationary magnetic field source applies a stationary magnetic field to the coil. An internal magnetic field source is disposed within a cavity of the coil to apply a moving magnetic field to the coil. The stationary magnetic field interacts with the moving magnetic field to generate an electrical energy in the coil.

RELATED APPLICATION

This application is related to U.S. patent application Ser. No. 12/478,429, filed Jun. 4, 2009 and titled “External Split Field Generator,” which is incorporated by reference.

BACKGROUND

1. Technical Field

This application relates to devices that convert mechanical energy into electrical energy and, more particularly, to generating electrical energy through magnetic field interactions.

2. Related Art

A generator converts mechanical energy into electrical energy. Most generators include an armature and a magnetic field source. Electrical energy may be induced in a conductive member of the armature when there is a relative movement between the armature and a magnetic field. In some implementations, electrical energy may be generated at the armature by passing a moving magnetic field across a stationary armature. In these configurations, the armature would be the stator of the generator and the magnetic field source would be the rotor of the generator. In other implementations, the electrical energy may be generated at the armature by moving the armature through a stationary magnetic field. In these configurations, the magnetic field source would be the stator of the generator and the armature would be the rotor of the generator. When mechanical energy (e.g., a rotation force) is applied to the rotor of the generator, an electrical energy (e.g., current and voltage) may be induced in the armature. The induced electrical energy may then be output to power other electrical devices.

SUMMARY

A generator includes a coil of conductive material. A stationary magnetic field source applies a stationary magnetic field to the coil. An internal magnetic field source is disposed within a cavity of the coil to apply a moving magnetic field to the coil. The stationary magnetic field interacts with the moving magnetic field to generate an electrical energy in the coil.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A generator may include an armature, a moving magnetic field source, and a stationary magnetic field source. Electrical energy may be induced in a conductive coil of the armature in response to an interaction between the armature, the moving magnetic field, and the stationary magnetic field. The moving magnetic field source may be positioned adjacent to a substantially neutral point of the conductive coil where the amount of flux from the moving magnetic field source would be balanced across both sides of the coil about equally. In this position, the moving magnetic field source alone may not induce much, if any, electrical energy in the coil. That result, however, may be substantially different when the stationary magnetic field is applied to the coil. The stationary magnetic field may be generated to pull magnetic flux from the moving magnetic field source back and forth across the coil as the polarity of the moving magnetic field alternates between north and south. When the moving magnetic field source is showing the coil a north polarity, more of the flux will be located in one side of the coil. When the moving magnetic field source is showing the coil a south polarity, more of the flux will be located in the other side of the coil. This flux interaction between the coil, the moving magnetic field, and the stationary magnetic field may result in an increased efficiency of the generator.

FIG. 1is a generator102that uses moving and stationary magnetic fields to generate electrical energy. The generator102includes an internal magnetic field source104and an armature106. The internal magnetic field source104may generate a moving magnetic field that interacts with a stationary magnetic field to induce an electrical energy in the armature106.

The internal magnetic field source104includes a magnet108and a shaft110. The magnet108produces a moving magnetic field in the vicinity of the armature106. In one implementation, the magnet108may be a permanent magnet with multiple poles. As the magnet108is rotated about the axis of the shaft110, a conductive member of the armature106may experience an alternating polarity from the internal magnetic field source104. The portion of the magnet108nearest to the conductive member of the armature106may alternate between being a north pole and a south pole. In one implementation, the magnet108may have one north pole and one south pole. Therefore, the armature106may experience two pole changes per full rotation of the shaft110(e.g., from north to south, and then from south back to north). Alternatively, the magnet108may have more than one north pole and more than one south pole. Therefore, the armature106may experience more than two pole changes per full rotation of the shaft110. If the magnet108has two north poles alternating with two south poles, then the armature106may experience four pole changes per full rotation of the shaft110. Other implementations of the magnet108may include any other number of poles to provide different numbers of pole changes per rotation of the shaft110. In one such implementation, the magnet108may be a combination of multiple magnets that are arranged so that the same polarity is facing out all the way around the magnet108. In this implementation, the pole changes experienced at the armature106may result from transitions between one pole, such as a north pole, to a magnetically neutral area of the magnet108. Another transition would then occur when the magnetically neutral area transitions back to another north pole as the magnet108rotates.

In another implementation, the magnet108may comprise a field source coil. To generate a moving magnetic field, an alternating current may be applied to the field source coil. In this implementation, the alternating current excited coil generates a moving magnetic field without moving any mechanical parts. When the alternating current is flowing in one direction through the field source coil, the magnet108will have a first polarity. When the alternating current is flowing in the other direction through the field source coil, the magnet108will have the opposite polarity. In this configuration, the generator102may operate as a transformer.

The armature106includes a frame112, a coil114, a first stationary magnetic field source116, and a second stationary magnetic field source118. The coil114may be formed from a conducting material, such as a copper wire. The coil114may be disposed about the frame112. In one implementation, the coil114may include one or more conductive windings wrapped around the frame112.

The frame112may include a core120, one or more cavities122, and an outer surface124. The coil114may be wound on the outer surface124of the frame112so that the coil114is wrapped about the core120. The portion of the frame112that supports the coil114may be made of a non-conducting and non-magnetizing material, such as wood, plastic, or the like. The core120may be made from a magnetizing material, such as iron, steel, ferrous alloys, or the like.

The cavity122of the frame112provides a space for the internal magnetic field source104to generate a moving magnetic field near the coil114. The internal magnetic field source104may be rotated about an axis inside the cavity122. The axis may be the axis of the rotating shaft110. The frame112may include a passageway that allows the rotating shaft110to reach the internal magnetic field source104in the cavity122. The cavity122may be filled with a magnetizing material that at least partially surrounds the internal magnetic field source104. The filler material may be placed around the internal magnetic field source104in a way that allows rotation of the internal magnetic field source104.

The stationary magnetic field sources116and118may be substantially stationary relative to the coil114. In one implementation, the stationary magnetic field sources116and118may be connected with the armature106. Alternatively, the stationary magnetic field sources116and118may be an integral portion of the armature106. The stationary magnetic field source116may be disposed on a first end portion of the frame112or core120. In one implementation, the first end portion may be the outermost end of the frame112or core120. In another implementation, the first end portion may be any portion of the frame112or core120located on that side of the coil114. The stationary magnetic field source116may be located at a point to the left of the coil114(based on the perspective ofFIG. 1). The stationary magnetic field source118may be disposed on a second end portion of the frame112or core120. In one implementation, the second end portion may be the outermost portion of the frame112or core120. In another implementation, the second end portion may be any portion of the frame112or core120located on that side of the coil114. The stationary magnetic field source118may be located at a point to the right of the coil114(based on the perspective ofFIG. 1).

The stationary magnetic field sources116and118may comprise permanent magnets or direct current energized elements, such as coils. The polarity of the stationary magnetic field source116is opposite the polarity of the stationary magnetic field source118. The stationary magnetic field sources116and118are positioned to be attracted to each other. InFIG. 1, the south pole of the stationary magnetic field source116is closer to the coil114than the north pole of the stationary magnetic field source116. The north pole of the stationary magnetic field source118is closer to the coil114than the south pole of the stationary magnetic field source118. In this configuration, there is an attraction between the south pole of the stationary magnetic field source116and the north pole of the stationary magnetic field source118. In other implementations, the north pole of the stationary magnetic field source116and the south pole of the stationary magnetic field source118may be facing the coil114to provide the attraction between the stationary magnetic field sources116and118.

The stationary magnetic field sources116and118apply a stationary magnetic field to the coil114. In one implementation, the stationary magnetic field sources116and118may apply a stationary magnetic field along a substantially longitudinal axis of the coil114. When the stationary magnetic field sources116and118are disposed on the frame112that supports the coil114, the magnetic field between the stationary magnetic field sources116and118passes along or through the core120of the frame112. When the coil114is wound on the frame112about the core120, the core120may define the longitudinal axis of the coil114. Therefore, the stationary magnetic field may pass along the longitudinal axis of the coil114by passing along or through the core120.

The magnetic strength and position of the stationary magnetic field sources116and118may be based on a desired electrical output of the armature106. For example, the electrical output from the armature106may depend on the strength and position of the stationary magnetic field sources116and118. The strength and position of the stationary magnetic field sources116and118may be set so that the stationary magnetic field is strong enough to sufficiently pull the magnetic flux from the internal magnetic field source104back and forth across the coil114. If the stationary magnetic field sources116and118are far away or are weak, the stationary magnetic field may not be strong enough to sufficiently pull the magnetic flux from the internal magnetic field source104back and forth across the coil to induce electrical energy in the coil as the internal magnetic field source104alternates polarity. Alternatively, if the stationary magnetic field sources116and118are too strong or too close together, then the stationary magnetic field may interfere with the ability of the moving magnetic field from the internal magnetic field source104to interact as strongly with the coil114. The optimal position and strength of the stationary magnetic field sources116and118may be based on the material used to form the core120, the size of the coil114, and/or the position of the internal magnetic field source104relative to the coil114. The strength and position of the stationary magnetic field sources116and118may be adjusted until a desired output is achieved on the armature106based on the other selected components and attributes of the generator102.

In one implementation of the generator102, the stationary magnetic sources116and118may be N-42 Neodymium, ⅞ of an inch in diameter, ⅛ of an inch thick, and with a surface field of about 2885 Gauss (0.2885 Tesla). Alternatively, the surface field may be about 1000 Gauss to about 5000 Gauss, although the range may depend on the magnetic field spacing and the core material. The strength of the external magnetic field source104may be about 2500 Gauss (0.25 Tesla). The distance of the external magnetic field source104may be about 1 mm from the coil114. Alternatively, the external magnetic field source104may be positioned to be closer or further away from the coil114, such as up to several inches away from the coil114. Any of these sizes, numbers, or measurements may be adjusted based on the intended application.

The internal magnetic field source104may be positioned adjacent to a substantially neutral point126of the coil114. Depending on the shape of the coil114, the internal magnetic field source104may be positioned substantially perpendicular to the substantially neutral point126of the coil114. The substantially neutral point126may be the point in the coil114where the amount of flux from the internal magnetic field source104is balanced across both sides of the coil114about equally (without the interaction with the stationary magnetic field). If the internal magnetic field source104is located adjacent to the neutral point126of the coil114, then the flux change from the internal magnetic field source104may produce a minimal induced electromagnetic force in the coil before addition of the stationary magnetic field from the stationary magnetic field sources116and118. In this position, due to the balance across the coil, the moving magnetic field alone may not induce much, if any, electrical output from the coil114. That result, however, may be substantially different when the stationary magnetic field is applied to the coil114.

To identify the substantially neutral point126of the coil114, the internal magnetic field source104may be placed adjacent to a first point on the inner side of the coil114. The internal magnetic field source104may then be rotated to generate a moving magnetic field in the vicinity of the coil114before the stationary magnetic field is applied to the coil114(e.g., before stationary magnetic field sources116and118are placed on the armature106or other location). As the internal magnetic field source104rotates in the first chosen location, the output voltage from the armature106may be monitored. If the armature106is outputting little or no voltage as the internal magnetic field source104rotates at the first chosen location, then that location may be near the substantially neutral point126of the coil114. If the armature106is transmitting a relatively large amount of voltage as the internal magnetic field source104rotates at the first chosen location, then that location may not be near the substantially neutral point126of the coil114. In that situation, the internal magnetic field source104may be moved adjacent to a second point on the inside of the coil114. The output voltage is measured with the internal magnetic field source104rotating at this new location. Once a position is determined for the internal magnetic field source104that results in little or no output voltage from the armature106(before the stationary magnetic field is applied to the coil114), then that position may be identified as the substantially neutral point126of the coil114.

When the internal magnetic field source104rotates at the neutral point126of the coil114, no output voltage may result at the armature (before the stationary magnetic field is applied to the coil114). In practice, however, some small amount of voltage may be transmitted from the armature106even if the neutral point126of the coil114is properly identified. Therefore, the neutral point126may include the absolute neutral point of the coil114as well as surrounding areas that may result in some small amount of voltage. The acceptable level of voltage induced when the internal magnetic field source104is at the neutral point126varies based on user defined tolerances as well as the desired strength of the output voltage. In one implementation, the neutral point may encompass several different possible positions for the internal magnetic field source104within an area around the absolute neutral point so that the output voltage, when the stationary magnetic sources116and118are not in place, would be about 5% of the output voltage that would occur when the stationary magnetic sources116and118are in place. In other implementations, other output voltage tolerance levels may be used, such as 20%, 10%, 1%, 0.1%, or the like.

In one implementation where the expected output voltage is about 4 volts when the stationary magnetic sources are in place, the output voltage when the stationary magnetic sources are removed may be in the range of about 5 mV (e.g., about 0.1% of the 4 volt expected output). However, the output voltage when the stationary magnetic sources are removed may be higher or lower than 5 mV, depending on the size and uniformity of the coil114, and the acceptable positioning of the external magnetic field source104around the neutral point126.

When the coil114is substantially uniform and symmetric (e.g., the individual windings of the coil114are uniformly distributed along the length of the coil114), the substantially neutral point126of the coil114may comprise the center point of the coil along the length of the coil, as shown inFIG. 1. Therefore, the internal magnetic field source104may be placed substantially perpendicular to the center point of the coil114. If the coil114is not substantially uniform or symmetric, then the substantially neutral point126may be offset from the center of the coil114(e.g., to the left or right).

FIG. 2is a cross-sectional view of the generator102ofFIG. 1(e.g., a cross-sectional slice at the center line ofFIG. 1). Multiple instances of the internal magnetic field source104may be aligned inside of one coil114. The multiple internal magnetic field sources104may be disposed within one common cavity122, as shown inFIG. 2. Alternatively, the multiple internal magnetic field sources104may be disposed within separate individually-sized cavities. By using multiple internal magnetic field sources104within the same coil114, the flux change experienced at the coil114may be increased. By increasing the amount of flux change, the amount of voltage induced in the coil114may be increased.

A first instance of the internal magnetic field source104may apply a first moving magnetic field to the coil114. A second instance of the internal magnetic field source104may apply a second moving magnetic field to the coil114. The second internal magnetic source may be aligned relative to the coil114so that the polarity of the second internal magnetic field source experienced at the coil114substantially matches the polarity of the first internal magnetic field source. As the multiple internal magnetic field sources are rotated about their respective axes, each internal magnetic field source may show substantially the same polarity to the coil114at a given time. When the south pole of the first internal magnetic field source is nearest to the coil114, the south pole of the second internal magnetic field source may also be nearest to the coil114. As the internal magnetic field sources continue to rotate, the north pole of the first internal magnetic field source may be nearest to the coil114at the same time the north pole of the second internal magnetic field source is nearest to the coil114.

FIGS. 3-8show the effect of the internal magnetic field source104rotating near the coil114. As the internal magnetic field source104rotates polarity, an interaction between the stationary magnetic field and the moving magnetic field may pull magnetic flux associated with the internal magnetic field source104back and forth across the coil114. The coil114responds by opposing this change with a counter electromagnetic field. The stationary magnetic field sources116and118inFIGS. 3-8are shown with an opposite polarity as compared toFIG. 1. InFIGS. 3-8, the north pole of the stationary magnetic field source116is closer to the coil114than the south pole of the stationary magnetic field source116, and the south pole of the stationary magnetic field source118is closer to the coil114than the north pole of the stationary magnetic field source118. Voltage plots302,402,502,602,702, and802show the voltage levels at the output nodes of the coil114around the time frame that corresponds to the orientation of the internal magnetic field source104shown in the respective figures. The amplitude of the output voltages may be dependent on the strength of the stationary magnetic field sources116and118and the speed of rotation of the internal magnetic field source104.

InFIG. 3, the north pole of the field source104is moving towards the coil114. As the north pole begins approaching the coil114, magnetic flux304from the internal magnetic field source104will be attracted towards the stationary magnetic field source118. Although some of the magnetic flux304may be experienced in the side portion of the coil114that is nearer to the stationary magnetic source116, more of the magnetic flux304will be experienced in the side portion of the coil114that is nearer to the stationary magnetic source118when a north pole of the internal magnetic field source104is closer to the coil114. The stationary magnetic field between the stationary magnetic field sources116and118pulls the magnetic flux304from the internal magnetic field source104across the portion of the coil114nearer to stationary magnetic field source118. The magnetic flux304may be pulled in that direction because the magnetic flux304from the north pole of the internal magnetic field source104is attracted to the south pole of the stationary magnetic field source118. Magnetic flux308may also pass between the stationary magnetic field source116and the internal magnetic field source104. The magnetic flux308may pass through the core of frame that supports the coil114.

The magnetic flux304that passes across the coil114induces a coil flux306through the coil114. When the north pole of the internal magnetic field source104is approaching, the coil flux306will travel from the portion of the coil114near the stationary magnetic source118to the portion of the coil114near the stationary magnetic source116. The interaction between the coil114, the stationary magnetic field, and the moving magnetic field induces a current and voltage in the coil114. The voltage level at the output nodes of the coil114is illustrated in the voltage plot302. The induced voltage may increase from zero as the internal magnetic field source104rotates until a peak voltage is achieved. As the internal magnetic field source104continues to rotate, the induced voltage begins to decease towards zero again.

InFIG. 4, the north pole of the field source104is moving away from the coil114. As the north pole moves away from the coil114, magnetic flux404from the internal magnetic field source104will be attracted towards the stationary magnetic field source118. The stationary magnetic field between the stationary magnetic field sources116and118pulls the magnetic flux404from the internal magnetic field source104across the portion of the coil114nearer to stationary magnetic field source118. The magnetic flux404may be pulled in that direction because the magnetic flux404from the north pole of the internal magnetic field source104is attracted to the south pole of the stationary magnetic field source118. Magnetic flux408may also pass between the stationary magnetic field source116and the internal magnetic field source104. The magnetic flux408may pass through the core of frame that supports the coil114.

The magnetic flux404that passes across the coil114induces a coil flux406through the coil114. When the north pole of the internal magnetic field source104is moving away from the armature106, the coil flux406will travel from the portion of the coil114near the stationary magnetic source116to the portion of the coil114near the stationary magnetic source118. The coil flux406when the north pole of the internal magnetic field source104is moving away from the armature106(e.g.,FIG. 4) may be in the opposite direction as the coil flux306when the north pole of the internal magnetic field source104is approaching the armature106(e.g.,FIG. 3). The interaction between the coil114, the stationary magnetic field, and the moving magnetic field induces a current and voltage in the coil114. The change in coil flux direction (compared to the direction inFIG. 3) results in a change in induced current direction and thus an output voltage with the opposite polarity. The voltage level at the output nodes of the coil114is shown in the voltage plot402. The induced voltage may increase from zero (with an opposite polarity as compared to the voltage induced atFIG. 3) as the internal magnetic field source104rotates until a peak voltage is achieved. As the internal magnetic field source104continues to rotate, the induced voltage begins to decease and approach zero.

InFIG. 5, the portion of the field source104that is closest to the coil114is neither a north pole nor a south pole.FIG. 5shows the north pole of the field source104moved away from the coil114. It is substantially equidistant from the coil as the south pole of the field source104. When neither pole of the field source104is facing the coil114, the voltage induced in the coil114may be near zero as shown in voltage plot502. As the field source104continues rotating and begins to move the south pole of the field source104towards the coil114, the voltage output from the coil114may move away from zero.

InFIG. 6, the south pole of the field source104is shown moving towards the coil114. As the south pole approaches the coil114, magnetic flux604may pass between the internal magnetic field source104and the stationary magnetic field source116. The magnetic flux604may pass from the stationary magnetic source116to the internal magnetic field source104. Although some of the magnetic flux604may be experienced in the side portion of the coil114that is nearer to the stationary magnetic source118, more of the magnetic flux604may be experienced in the side portion of the coil114that is nearer to the stationary magnetic source116when a south pole of the internal magnetic field source104is nearer to the coil114. The stationary magnetic field between the stationary magnetic field sources116and118may pull the magnetic flux604across the portion of the coil114nearer to the stationary magnetic field source116. The magnetic flux604may be pulled in that direction when the magnetic flux604from the north pole of the stationary magnetic field source116is attracted to the south pole of the internal magnetic field source104. Magnetic flux608may also pass between the internal magnetic field source104and the stationary magnetic field source118. The magnetic flux608may pass through the core of frame that supports the coil114.

The magnetic flux604that passes across the coil114induces a coil flux606through the coil114. When the south pole of the internal magnetic field source104is approaching and the magnetic flux604travels between the internal magnetic field source104and the stationary magnetic source116, the coil flux606will travel from the portion of the coil114near the stationary magnetic source118to the portion of the coil114near the stationary magnetic source116.

InFIGS. 3 and 6, the coil flux direction may be the same. When the north pole of the internal magnetic field source104is approaching the coil114(FIG. 3), the coil flux direction may be the same as when the south pole of the internal magnetic field source104is approaching the coil114(FIG. 6). The interaction between the coil114, the stationary magnetic field, and the moving magnetic field induces a current and voltage in the coil114. The voltage level at the output nodes of the coil114is shown in the voltage plot602. In plots302and602, the output voltage may be about the same (in magnitude and polarity) when either the north pole or the south pole of the internal magnetic field source104is approaching the armature106. Alternatively, the output voltages of the two scenarios may be different based on other aspects of the generator102, such as non-uniformities in magnetic source position or strength. As shown in the plot602, the induced voltage may increase from zero as the internal magnetic field source104rotates until a peak voltage is achieved. As the internal magnetic field source104continues to rotate, the induced voltage begins to decease towards zero again.

InFIG. 7, the south pole of the field source104is shown moving away from the coil114. As the south pole moves away from the coil114, magnetic flux704may pass between the internal magnetic field source104and the stationary magnetic field source116. The magnetic flux704may pass from the stationary magnetic source116to the internal magnetic field source104. The stationary magnetic field between the stationary magnetic field sources116and118pulls the magnetic flux704across the portion of the coil114nearer to the stationary magnetic field source116. The magnetic flux704may be pulled in that direction because the magnetic flux704from the north pole of the stationary magnetic field source116is attracted to the south pole of the internal magnetic field source104. Magnetic flux708may also pass between the internal magnetic field source104and the stationary magnetic field source118. The magnetic flux708may pass through the core of frame that supports the coil114.

The magnetic flux704that passes across the coil114induces a coil flux706through the coil114. When the south pole of the internal magnetic field source104is moving away from the armature, the coil flux706will travel from the portion of the coil114near the stationary magnetic source116to the portion of the coil114near the stationary magnetic source118. The coil flux when the south pole of the internal magnetic field source104is moving away from the coil114(e.g.,FIG. 7) may be in the opposite direction as the coil flux606when the south pole of the internal magnetic field source104was approaching the coil114(e.g.,FIG. 6). The change in coil flux direction (compared to the direction inFIG. 6) results in a change in induced current direction and thus an output voltage with the opposite polarity.

InFIGS. 4 and 7, the coil flux direction may be the same. When the north pole of the internal magnetic field source104is moving away from the coil114(FIG. 4), the coil flux direction may be the same as when the south pole of the internal magnetic field source104is moving away from the coil114(FIG. 7). The interaction between the coil114, the stationary magnetic field, and the moving magnetic field induces a current and voltage in the coil114. The voltage level at the output nodes of the coil114is illustrated in the voltage plot702. As shown in plots402and702, the output voltage may be about the same (in magnitude and polarity) when either the north pole or the south pole of the internal magnetic field source104is moving away from the coil114. Alternatively, the output voltages of the two scenarios may be different based on other aspects of the generator102, such as non-uniformities in magnetic source position or strength. In plot702, the induced voltage may increase from zero (with an opposite polarity as compared to the voltage induced atFIG. 6) as the internal magnetic field source104rotates until a peak voltage is achieved. As the internal magnetic field source104continues to rotate, the induced voltage begins to decease towards zero again.

InFIG. 8, the portion of the field source104that is closest to the coil114is neither a north pole nor a south pole.FIG. 8shows the situation where the south pole of the field source104has moved away from the coil114and is substantially equidistant from the coil as the north pole of the field source104. When neither pole of the field source104is facing the armature106, the voltage induced in the coil114may be near zero. As the field source104continues rotating and begins to move the north pole of the field source104towards the coil114, then the voltage output from the coil114will again move away from zero, as shown inFIG. 3.

FIGS. 3-8illustrate a full rotation of the internal magnetic field source104. The internal magnetic field source104includes a north pole and a south pole. Other implementations use an internal magnetic field source104with additional poles. Through the progression ofFIGS. 3-8, the generator102may produce two flux changes at the coil114per pole of the internal magnetic field source104for each full rotation of the internal magnetic field source104. Because the internal magnetic field source104ofFIGS. 3-8includes two poles, the generator102produces four flux changes per full rotation of the internal magnetic field source104. A first flux change occurs in the time betweenFIGS. 3 and 4.FIG. 3shows the coil flux306moving from right to left, andFIG. 4shows the coil flux406moving from left to right. A second flux change occurs in the time betweenFIGS. 4 and 6.FIG. 4shows the coil flux406moving from left to right, andFIG. 6shows the coil flux606moving from right to left. A third flux change occurs in the time betweenFIGS. 6 and 7.FIG. 6shows the coil flux606moving from right to left, andFIG. 7shows the coil flux706moving from left to right. A fourth flux change occurs in the time betweenFIGS. 7 and 3.FIG. 7shows the coil flux706moving from left to right, andFIG. 3shows the coil flux306moving from right to left.

The two flux changes per pole of the internal magnetic field source104for each full rotation of the internal magnetic field source104results in an increase in frequency compared to a generator that produces only one flux change per pole of the internal magnetic field source104for each full rotation of the internal magnetic field source104. This increase in frequency may increase the efficiency of the generator with higher power densities. Using the flux interaction between the moving and stationary magnetic fields to increase the generator frequency may result in higher generator efficiency without requiring additional field source poles or armature windings. Other implementations, however, may use additional field source poles and/or armature windings to produce even higher generator efficiencies.

FIG. 9shows an output waveform902of electrical energy induced in the armature106of the generator102in response to a half rotation of the internal magnetic field source104. The output waveform902may illustrate the voltage level that corresponds to the north pole of the internal magnetic field source104approaching the coil114(as shown inFIG. 3) and then moving away from the coil114(as shown inFIG. 4). Alternatively, the output waveform902may illustrate the voltage level that corresponds to the south pole of the internal magnetic field source104approaching the coil114(as shown inFIG. 6) and then moving away from the coil114(as shown inFIG. 7). The output waveform902may include peaks904and906. In one implementation, the peak904may correspond to the north pole approaching the coil114and the peak906may correspond to the north pole moving away from the coil114. In another implementation, the peak904may correspond to the south pole approaching the coil114and the peak906may correspond to the north south pole moving away from the coil114. Alternatively, the peak904may correspond to the south pole moving away from the coil114and the peak906may correspond to the north pole approaching the coil114. In other implementations, the peak904may correspond to the north pole moving away from the coil114and the peak906may correspond to the south pole approaching the coil114.

FIG. 10shows an output waveform1002of electrical energy induced in the armature106of the generator102in response to a full rotation of the internal magnetic field source104. The output waveform1002includes the peaks904and906shown inFIG. 9corresponding to a half rotation of the internal magnetic field source104. The output waveform1002also includes peaks1004and1006to complete a full rotation of the internal magnetic field source104. The four peaks904,906,1004, and1006of alternating polarity represent the four flux changes per full rotation of an internal magnetic field source that has two poles.

If the peaks904and906correspond to the north pole of the internal magnetic field source104approaching and then moving away from the coil114, then the peaks1004and1006may correspond to the south pole of the internal magnetic field source104approaching and then moving away from the coil114. Alternatively, if the peaks904and906correspond to the south pole of the internal magnetic field source104approaching and then moving away from the coil114, then the peaks1004and1006may correspond to the north pole of the internal magnetic field source104approaching and then moving away from the coil114.

FIGS. 11 and 12show generators with multiple armatures and multiple magnetic field sources. InFIG. 11, the generator1102includes multiple instances of the internal magnetic field source104aligned with the respective neutral points126of multiple instances of the armature106. The multiple armatures106may be separated by an amount of space so that their respective magnetic fields are isolated from each other. Alternatively, an isolation material (e.g., a ferrous or ferrite material) may be placed between the armatures106to isolate one armature from the other. The isolation material may be positioned so that there is a gap between the isolation material and the adjacent armatures. In one implementation, the stationary magnet of one armature is positioned in attraction with the adjacent stationary magnet of the other armature, as shown inFIGS. 11 and 12. In other implementations, the stationary magnet of one armature may be positioned to be in repulsion with the adjacent stationary magnet of the other armature. Positioning the stationary magnet of one armature to be in repulsion from the adjacent stationary magnet of the other armature may make it easier to isolate the adjacent armatures through separation by a ferrous/ferrite metal.

The multiple internal magnetic field sources104may be located on different rotating shafts or they may both be located on a single shaft. As the multiple internal magnetic field sources104rotate, the moving magnetic field interacts with the respective coils114and stationary magnetic fields to generate electrical energy in each of the coils114.

InFIG. 12, the phase of one of the internal magnetic sources104of the generator1202is about 90° out of phase with the other of the internal magnetic sources104. In one implementation, as shown inFIG. 12, the south pole of the left internal magnetic field source104may be facing a coil114when neither pole of the right internal magnetic field source104is directly facing a coil114. When the internal magnetic field sources104turn about 90° together, the south pole of the right internal magnetic field source104may face a coil114when neither pole of the left internal magnetic field source104is directly facing a coil114. This arrangement generates two current phases.

By staggering one of the internal magnetic sources104about 90° out of phase with the other of the internal magnetic sources104, the amount of magnetic drag experienced as the internal magnetic sources104rotate may be reduced. As one of the internal magnetic field sources104is rotating away from a portion of the armature106(e.g., the core of the frame), another of the internal magnetic field sources104may be rotating towards the core of the armature106. When an internal magnetic field source104is rotating away from the core of the armature106, there may be an attraction force between the internal magnetic field source104and the core. That attraction force may make it more difficult to turn the shaft that supports the internal magnetic field source104. When an internal magnetic field source104is rotating toward the core of the armature106, there may also be an attraction force between the internal magnetic field source104and the core. The attraction force between the internal magnetic field source104moving towards the core of its associated armature106may counteract at least some of the attraction force between the internal magnetic field source104moving away from the core of its associated armature106. Therefore, the multiple phase system of the generator1202may reduce the amount of mechanical energy required to turn the shaft.

FIGS. 13-15show other configurations for the stationary magnetic field sources of a generator. InFIG. 13, the generator1302includes stationary magnetic field sources116and118disposed on the ends of a bent core120(e.g., horseshoe shaped).

FIG. 14shows a generator1402with a coil114wrapped about a core120that may carry multiple stationary magnetic fields along the axis of the coil114. A first stationary magnetic field may pass between the stationary magnetic field sources1404and1406through the core120. A second stationary magnetic field may pass between the stationary magnetic field sources1408and1410through the core120. Additional stationary magnetic sources may also be positioned to pass additional stationary magnetic fields through the core120.

FIG. 15shows an end view of a generator1502that includes four or more stationary magnetic fields passing through a core120of an armature. A first magnetic field passes through the core120between the stationary magnetic field source1504and another stationary magnetic field source that is not visible in this perspective. A second magnetic field passes through the core120between the stationary magnetic field source1506and another stationary magnetic field source that is not visible in this perspective. A third magnetic field passes through the core120between the stationary magnetic field source1508and another stationary magnetic field source that is not visible in this perspective. A fourth magnetic field passes through the core120between the stationary magnetic field source1510and another stationary magnetic field source that is not visible in this perspective. The other stationary magnetic sources that are not visible in this perspective may be disposed on the other end of a bent core120(e.g., a horseshoe shaped core). These other magnetic field sources may be directly below the stationary magnetic field sources1504,1506,1508, and1510in the perspective ofFIG. 15. Furthermore, additional stationary magnetic sources (e.g., more than the four shown) may also be positioned to pass additional stationary magnetic fields through the core120.

The term “coupled” may encompass both direct and indirect coupling. Thus, first and second parts are said to be coupled together when they directly contact one another, as well as when the first part couples to an intermediate part which couples either directly or via one or more additional intermediate parts to the second part. The term “position,” “location,” or “point” may encompass a range of positions, locations, or points.