Generator pole slip detection

Abstract

Disclosed are a system and method for protecting a generator set from magnetic pole slip. The system may include a generator, a prime mover, and a controller. The generator includes a stator and a rotor. The prime mover is configured to drive the rotor to rotate. The controller may be configured to: determine a mechanical state of the generator based on data related to translational displacement of the rotor; determine an electrical state of the generator based on (a) a load angle or (b) a load angle and a rate of change of the load angle associated with rotation of the rotor in the stator; determine an operating state of the generator based on a fusion of the mechanical state and the electrical state; if the operating state is a magnetic pole slip warning, activate an output member to display or issue a warning; and if the operating state is a magnetic pole slip, activate a protective action.

Description

Technical Field

[0001] The present invention relates generally to a generator set (also referred to as a "genset") and, more particularly, to a system for protecting a generator from pole slip. Background Art

[0002] A generator set includes a generator and a prime mover. A generator is typically an electric motor configured to convert electrical energy into rotational torque or vice versa for use in any of a variety of different applications, including power generation, power backup, offshore drilling, machine tools, traction motors, industrial work machines, marine work machines, and the like. Such generators are typically used in conjunction with a prime mover, such as an engine. When fuel is burned within the prime mover, mechanical rotation is generated, which drives the generator to generate electrical energy. More specifically, a main power source rotates the rotor of the motor, causing electromagnetic interaction that generates electrical energy, which is then used by one or more loads connected to the motor.

[0003] Conditions such as low excitation (e.g., low excitation voltage), sudden load changes, and even circuit faults can cause the magnetic poles in the generator to lose synchronism, a condition often referred to in the art as "pole slip." Pole slip can damage generator components and can also lead to unstable power generation. Pole slip is difficult to distinguish from power swing because both power swing and pole slip conditions experience oscillations during the initial stages of the generator's transition from power swing to pole slip. However, while a generator typically recovers and becomes stable again after experiencing a power swing, this is not typically the case with pole slip. In other words, after experiencing a pole slip condition, the generator may continue to progress and become unstable.

[0004] U.S. Patent No. 8,278,883 (the '883 patent), issued on October 2, 2012, relates to an apparatus for measuring the load angle and detecting pole slip in a synchronous generator. The '883 patent describes an apparatus comprising means for sensing a waveform generated by a permanent magnet motor, means for sensing a waveform generated by a host machine, and means for comparing the waveform generated by the permanent magnet motor with the waveform generated by the host machine to produce a measurement of the load angle. The '883 patent further describes using the load angle measurement to provide a warning of potential pole slip. However, pole slip often occurs very quickly and action must be taken quickly. While the '883 patent can be beneficial, the pole slip condition may be flagged too late (already outside the stable region or moving outside the stable region very quickly), or the triggering of the pole slip condition may be too dependent on using a predictive estimate of the load angle. A better system is needed. Summary of the Invention

[0005] In one aspect of the present invention, a system for detecting a pole slip condition in a generator of a generator set is provided. The system includes a generator, a prime mover, and a controller. The generator may include a stator and a rotor rotatably disposed within the stator. The generator may be configured to rotate a rotor magnetic field in the stator and generate a stator magnetic field when the stator is electrically coupled to a load. The prime mover may include an output shaft operably connected to the rotor of the generator. The prime mover is configured to drive the rotor in rotation. The controller is in operable communication with the generator set. The controller may be configured to: determine a mechanical state of the generator based on data related to translational displacement of the rotor; determine an electrical state of the generator based on (a) a load angle or (b) a load angle and a rate of change of the load angle associated with rotation of the rotor in the stator; determine an operating state of the generator based on a fusion of the mechanical and electrical states; activate an output component to display or issue a warning if the operating state is a pole slip warning; and activate a protective action if the operating state is a pole slip warning.

[0006] In another aspect of the present invention, a method for protecting a generator set from magnetic pole slip is disclosed. The generator set includes a prime mover and a generator. The prime mover may include an output shaft operably connected to a rotor of the generator. The prime mover may be configured to drive rotation of the rotor. The generator includes a stator and a rotor rotatably disposed within the stator. The stator is electrically coupled to a load. The generator may be configured to rotate a rotor magnetic field in the stator and generate a stator magnetic field. The method may include: determining, by a controller in operable communication with the generator set, a mechanical state of the generator based on data related to translational displacement of the rotor; calculating, by the controller, a load angle and a rate of change of the load angle associated with rotation of the rotor in the stator; determining, by the controller, an electrical state of the generator based on (a) the load angle or (b) the load angle and the rate of change of the load angle; determining, by the controller, an operating state of the generator based on a fusion of the mechanical state and the electrical state; activating, by the controller, an output member to display or issue a warning if the operating state is magnetic pole slip warning; and activating, by the controller, a protective action if the operating state is magnetic pole slip warning.

[0007] In yet another aspect of the present invention, a system is provided. The system includes a generator set and a controller. The generator set includes a generator and a prime mover. The generator includes a stator and a rotor rotatably disposed within the stator. The generator may be configured to rotate a rotor magnetic field in the stator and generate a stator magnetic field when the stator is electrically coupled to a load. The prime mover may include an output shaft operatively connected to the rotor of the generator. The prime mover may be configured to drive rotation of the rotor. The controller is in operable communication with the generator set. The controller may be configured to: calculate a resultant displacement based on data related to translational displacement of the rotor; determine a mechanical state of the generator based on the resulting displacement; calculate a load angle and a rate of change of the load angle associated with rotation of the rotor in the stator; determine an electrical state of the generator based on (a) the load angle or (b) the load angle and the rate of change of the load angle; determine an operating state of the generator based on a fusion of the mechanical and electrical states; activate an output component to display or issue a warning if the operating state is pole-slipping-warning; and activate a protective action if the operating state is pole-slipping. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic diagram of an exemplary system according to the present invention;

[0009] Figure 2 It is taken along line 2-2 Figure 1 A schematic diagram of a cross section of a generator set;

[0010] Figure 3 is a flow chart of an exemplary method for detecting magnetic pole slip in a generator set according to the present invention;

[0011] Figure 4 is a schematic diagram of another exemplary system according to the present invention;

[0012] Figure 5 is a schematic diagram of exemplary load angles; and

[0013] Figure 6 A table showing exemplary fusions according to the present invention. DETAILED DESCRIPTION

[0014] Reference will now be made in detail to specific embodiments or features, examples of which are illustrated in the accompanying drawings. Generally, corresponding reference numerals will be used throughout the drawings to refer to the same or corresponding parts unless otherwise indicated.

[0015] As previously discussed, pole slip can be difficult to distinguish from power swing because both experience oscillations during their initial stages. However, while a generator typically recovers and becomes stable again after experiencing a power swing, this is not typically the case with pole slip. With pole slip, the generator may develop and remain in an unstable state. Because pole slip occurs rapidly, prompt action must be taken to mitigate its adverse effects. If detected too late, the generator may be damaged before it can be shut down or isolated. However, if a power swing is inaccurately predicted as a pole slip, unnecessary power generation interruption may occur.

[0016] The systems and methods disclosed herein protect a generator set from the adverse effects of pole slip by determining an operating state based on a fusion of (a) vibration-related mechanical characteristics and (b) electrical characteristics, while minimizing the likelihood of power swings being described as pole-slip. Figure 1 One example of such a system 100 is shown. The system 100 may include a generator set 102 and a controller 104. The system 100 may also include one or more displacement sensors 106, voltage sensors 108, and current sensors 110. The system 100 may also include an output member 112.

[0017] Generator set 102 includes a prime mover 114 and a generator 116 coupled to prime mover 114. Prime mover 114 includes an output shaft 118. For example, prime mover 114 may be an internal combustion engine having an output shaft 118 or any other similar power source suitable for outputting mechanical energy (e.g., rotational torque) at its output shaft 118. When fuel is combusted within prime mover 114, mechanical energy in the form of rotation is generated at output shaft 118, which drives generator 116 to generate electrical energy.

[0018] The generator 116 can be an electric machine, such as an AC synchronous generator, an AC induction motor, a switched reluctance motor, or other similar type of electric machine, which is configured to convert electrical energy into rotational torque or convert rotational torque into electrical energy for use in any of a variety of different applications, including power generation, backup power, offshore drilling, machine tools, traction motors, industrial work machines, marine work machines, etc.

[0019] Figure 2 It is taken along line 2-2 Figure 1 Schematic diagram of a cross section of the generator set 102. Figure 2 As shown, the generator 116 includes a stator 120 and a rotor 122, and the rotor 122 is rotatably disposed within the stator 120. The rotor 122 is operatively connected to the output shaft 118 of the prime mover 114 (see FIG. Figure 1 ). Stator 120 (such as Figure 2 ) can be electrically coupled to bus 124 (as shown Figure 1), for providing power to one or more loads 126 connected to the bus 124.

[0020] When the generator set 102 is operating in the generating mode, the rotor 122 (see Figure 2 ) electromagnetically interacts with the stator 120 so that a mechanical or rotational input at the rotor 122 (e.g., from Figure 1 The output shaft 118 of the prime mover 114 shown receives the rotation of the rotor 122 ( Figure 2 ), which causes electromagnetic interactions that produce electrical energy at the output of the stator 120 (used by one or more connected loads 126). For example, in one embodiment, a DC current is applied to windings (not shown) provided on the rotor 122 (such windings are referred to herein as "rotor windings"), thereby generating a "rotor magnetic field". The rotation of the rotor 122 causes the rotor magnetic field to rotate relative to the windings in the stator 120 (such windings are referred to herein as "stator windings" 128), which induces a three-phase voltage in the stator windings 128. When the load 126 (see Figure 1 ) is connected to the stator 120 of the generator 116 ( Figure 2 ), current begins to flow in stator winding 128, thereby generating a magnetic field ("stator magnetic field") in stator 120. As is known in the art, load angle δ is the rotation angle between the rotor magnetic field and the stator magnetic field for a synchronous field (the rotor magnetic field and the stator magnetic field rotate at synchronous speed) generated in stator 120. It is known that load angle δ increases as load 126 increases, and at Figure 5 The load angle δ between the rotor field axis and the stator field axis can be seen in .

[0021] Each of the one or more displacement sensors 106 is in operable communication with the controller 104. Each displacement sensor 106 is configured to measure data related to the translational displacement of the rotor 122. The translational displacement includes horizontal displacement of the rotor 122 along the x-axis, and / or vertical displacement of the rotor 122 along the y-axis, and / or displacement of the rotor 122 along the z-axis. For example, in one embodiment, the horizontal displacement may represent (translational) movement of the rotor 122 along the x-axis from the center of rotation 130 of the rotor 122, and the vertical displacement may represent (translational) movement of the rotor 122 along the y-axis from the center of rotation 130 of the rotor 122.

[0022] exist Figure 1In the exemplary embodiment shown, the displacement sensor 106a is positioned on the rear end 136 of the generator 116 at a location suitable for the displacement sensor 106a to measure data related to (or representative of) the horizontal (translational) displacement of the rotor 122 along the x-axis. In one exemplary embodiment, the displacement sensor 106a can be positioned on the stator 120 at the rear end 136 of the generator 116 at approximately the twelve o'clock position, although other locations near the rear end 136 can also be utilized. Figure 1 In the exemplary embodiment shown, the displacement sensor 106b may also be positioned on the rear end 136 of the generator 116 at a location suitable for the vertical displacement sensor 106b to measure data related to (or representative of) the vertical (translational) displacement of the rotor 122 along the y-axis. In one exemplary embodiment, the displacement sensor 106b may be positioned at approximately the nine o'clock position on the rear end 136 of the stator 120 of the generator 116, although other locations near the rear end 136 may also be utilized. Figure 1 In the exemplary embodiment shown, the displacement sensor 106c may be disposed on the rear end 136 of the generator 116 in a position suitable for the displacement sensor 106c to measure data related to (or representative of) the displacement of the rotor 122 along the z-axis. In one embodiment, the displacement sensor 106c may be disposed at approximately the nine o'clock position on the rear end 136 of the stator 120 of the generator 116, although other locations near the rear end 136 may also be utilized.

[0023] Alternatively, one or more displacement sensors 106 may be disposed at the front end 138 of the generator 116. For example, Figure 4 As shown in the exemplary embodiment of FIG, the displacement sensor 106a can be disposed on the front end 138 of the generator 116 at a location suitable for the displacement sensor 106a to measure data related to (or representative of) horizontal (translational) displacement. Figure 4 In an embodiment, the exemplary displacement sensor 106a may be positioned on the front end 138 of the generator 116 at approximately the twelve o'clock position, although other locations near the front end 138 may also be utilized. Figure 4 In the exemplary embodiment shown, the displacement sensor 106b may be positioned on the front end 138 of the generator 116 in a location suitable for the displacement sensor 106b to measure data related to (or representative of) the vertical (translational) displacement of the rotor 122 along the y-axis. In one exemplary embodiment, the displacement sensor 106b may be positioned on the front end 138 of the generator 116 at approximately the nine o'clock position, although other locations near the front end 138 may also be used. Figure 4In the exemplary embodiment shown, the displacement sensor 106c may be disposed on the front end 138 of the generator 116 in a position suitable for the displacement sensor 106c to measure data related to (or representative of) the displacement of the rotor 122 along the z-axis. In one embodiment, the displacement sensor 106c may be disposed on the front end 138 of the generator 116 at approximately the nine o'clock position, although other locations near the front end 138 may also be utilized.

[0024] In some embodiments, the data obtained by the individual displacement sensors 106a, 106b, 106c described above can be provided by a (single) displacement sensor 106, such as an accelerometer, which measures data related to the displacement of the rotor 122 (e.g., acceleration data), wherein the horizontal (translational) displacement of the rotor 122 along the x-axis, the vertical (translational) displacement of the rotor 122 along the y-axis, and optionally the (translational) displacement of the rotor 122 along the z-axis can be calculated by integrating the measured accelerations. The displacement sensor 106, such as an accelerometer, can be positioned in any of the locations described above for displacement sensors 106 for measuring data related to translational motion along the respective axes (x, y, z). For example, the displacement sensor 106, such as an accelerometer, can be positioned on the stator 120 at the rear end 136 of the generator 116.

[0025] Voltage sensor 108 can be operably connected to generator 116 to measure the three-phase AC voltage in stator winding 128. Voltage sensor 108 can be any voltmeter or combination of voltmeters known in the art for measuring three-phase AC voltage. Voltage sensor 108 is in operable communication with controller 104.

[0026] The current sensor 110 can be operably connected to the generator 116 to measure the current flowing in the stator winding 128 (e.g., when the load 126 is connected), or alternatively, obtain data representative of the current flowing in the stator winding 128 (e.g., when the load 126 is connected). The current sensor 110 can be any current meter or combination of current meters known in the art for measuring current in a three-phase power system. The current sensor 110 is in operable communication with the controller 104.

[0027] The controller 104 may include a processor 132 and a memory component 134. The controller 104 is in operable communication with the generator set 102, and more specifically, with the prime mover 114 and the generator 116 of the generator set 102. The controller 104 may also be in operable communication with the displacement sensor 106, the voltage sensor 108, the current sensor 110, the output member 112, and the bus 124. The controller 104 is configured to receive data related to (or representative of) the translational displacement of the rotor 122 and calculate a resultant displacement of the rotor 122. This translational displacement includes a horizontal (translational) displacement of the rotor 122 along the x-axis, and / or a vertical (translational) displacement along the y-axis, and / or a spatial (translational) displacement of the rotor 122 along the z-axis. The controller 104 is further configured to receive electrical data related to the rotation of the rotor 122 within the stator 120 and calculate a load angle and a rate of change of the load angle based on the electrical data. For example, the controller 104 is configured to receive voltage data from the voltage sensor 108 and current data from the current sensor 110 .

[0028] The controller 104 is further configured to determine a mechanical state of the generator 116 based on data related to the translational displacement of the rotor 122. As used herein, the term "mechanical state" refers to a state of the generator 116 related to pole slip, which is determined based on the translational displacement of the rotor 122 due to vibrations of the rotor 122. In an exemplary embodiment, the mechanical state can be one of three states: (1) pole slip is not currently occurring (the mechanical state is referred to herein as "mechanical-no-pole-slip"); (2) the generator 116 may be heading toward pole slip (the mechanical state is referred to herein as "mechanical-pole-slip-warning"); or (3) pole slip is occurring (the mechanical state is referred to herein as "mechanical-pole-slip").

[0029] The controller 104 is further configured to determine an electrical state of the generator 116 based on (a) the load angle δ or (b) the load angle δ and the rate of change of the load angle δ. As used herein, the term "electrical state" refers to a state of the generator 116 related to pole slip, which is determined based on (a) the load angle δ or (b) the load angle δ and the rate of change of the load angle δ. In an exemplary embodiment, the electrical state can be one of three states: (1) pole slip is not currently occurring (the electrical state is referred to herein as "electrical-no-pole slip"); (2) the generator 116 may be heading towards pole slip (the electrical state is referred to herein as "electrical-pole-slip-warning"); or (3) pole slip has occurred (the electrical state is referred to herein as "electrical-pole-slip"). The following table illustrates an exemplary embodiment of determining the electrical state according to the method herein. Because the threshold values ​​of the load angle δ and the rate of change of the load angle δ may vary between generators of different sizes, the values ​​in the following table are exemplary.

[0030]

[0031] Controller 104 is further configured to determine an operating state of generator 116 of genset 102 based on a fusion of the mechanical state and the electrical state, as described later herein. Controller 104 is further configured to activate output member 112 to display or issue a warning when the operating state is determined to be a "pole-slip-warning" state or a "pole-slip" state. Controller 104 is further configured to activate a protective action if the operating state is a pole-slip state. Exemplary protective actions that controller 104 may activate include shutting down generator 116 or genset 102, or isolating generator 116 from load 126.

[0032] The processor 132 may be a microcontroller, a digital signal processor, an electronic control module, an electronic control unit, a microprocessor, or any other suitable processor 132 known in the art. The processor 132 may execute instructions and generate control signals for calculating the resulting displacement of the rotor 122 based on data related to the translational displacement of the rotor 122, for calculating the load angle δ and the rate of change of the load angle δ based on the electrical data, for determining the mechanical state of the generator 116 based on the resulting displacement, for determining the electrical state of the generator 116 based on (a) the load angle δ or (b) the load angle δ and the rate of change of the load angle δ, for determining the operating state of the generator 116 of the generator set 102 based on a fusion of the mechanical state and the electrical state, for activating the output member 112 to display or issue a warning when the operating state is determined to be a "pole-slip-warning" state or "pole-slip", and for initiating preventive or remedial measures. Such instructions may be read into or incorporated into a computer-readable medium, such as the memory component 134, or provided external to the processor 132. In alternative embodiments, hard-wired circuitry may be used in place of or in combination with software instructions to implement the control methods.

[0033] As used herein, the term "computer-readable medium" refers to any non-transitory medium or combination of media that participates in providing instructions to processor 132 for execution. Such media may include all computer-readable media except transient propagating signals. Common forms of computer-readable media include, for example, floppy disks, disks, hard disks, magnetic tape, or any other magnetic medium, CD-ROMs, any other optical media, or any other computer-readable medium.

[0034] The controller 104 is not limited to one processor 132 and memory component 134. The controller 104 may include several processors 132 and memory components 134. In one embodiment, the processor 132 may be a parallel processor with access to a shared memory component 134. In another embodiment, the processor 132 may be part of a distributed computing system, where the processor 132 (and its associated memory component 134) may be located remotely from one or more other processors 132 (and its associated memory component 134) that are part of the distributed computing system.

[0035] The controller 104 may also be configured to retrieve formulas and other data necessary for the calculations discussed herein from the memory component 134 .

[0036] The output component 112 can be operably connected to the controller 104 or in communication with the controller 104. The output component 112 can include, but is not limited to, a visual display, a log, a horn, a flashing light, a buzzer, etc. The controller 104 can also be configured to send alarm notifications, warnings, etc. related to the operating status of the generator 116 of the generator set 102 to the output component 112.

[0037] A method for protecting a generator set 102 from pole slip is also disclosed. The method may include: determining, by a controller 104 in operable communication with the generator set 102, a mechanical state of the generator 116 based on data related to the translational displacement of the rotor 122; calculating, by the controller 104, a load angle δ and a rate of change of the load angle δ associated with rotation of the rotor 122 within the stator 120; determining, by the controller 104, an electrical state of the generator 116 based on (a) the load angle δ or (b) the load angle δ and the rate of change of the load angle δ; determining, by the controller 104, an operating state of the generator 116 based on a fusion of the mechanical state and the electrical state; activating, by the controller 104, an output member 112 to display or issue a warning if the operating state is pole-slip-warning; and activating, by the controller 104, a protective action if the operating state is pole-slip.

[0038] Industrial Applicability

[0039] In operation, the controller 104 may be configured to operate according to a predetermined method 300, e.g. Figure 3 shown. Figure 3 is an exemplary flow chart describing a method 300 for protecting genset 102 from pole slip.

[0040] In block 305, the controller 104 receives electrical data related to the rotation of the rotor 122 in the stator 120. This electrical data includes the three-phase voltages of the stator windings 128 (received from the voltage sensors 108) and the three-phase current measurements from the current sensors 110. The controller 104 calculates the load angle δ (in degrees) and the rate of change of the load angle δ using any suitable method known in the art.

[0041] In block 310, controller 104 receives data related to the translational displacement of rotor 122. This translational displacement includes horizontal (translational) displacement of rotor 122 along the x-axis, and / or vertical (translational) displacement of rotor 122 along the y-axis, and / or spatial (translational) displacement of rotor 122 along the z-axis. This data may be received from an accelerometer used as a "multi-axis" displacement sensor 106, or from multiple "single-axis" displacement sensors 106. In one embodiment, controller 104 calculates a resultant (combined) displacement based on the data related to the translational displacement of rotor 122. The process proceeds to block 330.

[0042] In block 315, the controller 104 determines whether the load angle δ is greater than a load angle threshold. If the load angle δ is greater than the load angle threshold, the controller 104 proceeds to block 340 to determine whether the electrical state of the generator 116 is an electrical-pole-slip electrical state. For example, in one exemplary embodiment, the load angle threshold may be set to a predetermined number of degrees (e.g., 150 degrees). If, in this exemplary embodiment, the load angle δ is greater than such predetermined number of degrees, the controller 104 determines that the electrical state of the generator 116 has transitioned to an electrical-pole-slip electrical state. If the load angle δ is less than or equal to the load angle threshold, the controller 104 proceeds to block 320.

[0043] In block 320, the controller 104 determines whether the load angle δ is greater than a load angle warning threshold. If the load angle δ is less than or equal to the load angle warning threshold, the controller 104 proceeds to block 340 and determines that the electrical state of the generator 116 is an electrical-no-pole-slip electrical state. If the load angle δ is greater than the load angle warning threshold, the controller 104 proceeds to block 325. For example, in one exemplary embodiment, the load angle warning threshold may be set to another predetermined number of degrees (e.g., 30 degrees). If the load angle δ is greater than such a predetermined number of degrees, the controller 104 proceeds to block 325.

[0044] In block 325, the controller 104 determines whether the rate of change of the load angle δ is greater than a rate-of-change threshold. If the rate of change of the load angle δ is less than or equal to the rate-of-change threshold, the controller 104 proceeds to block 340 and determines that the electrical state of the generator 116 is an electrical state of electrical-pole-slipping-warning. If the rate of change of the load angle δ is greater than the rate-of-change threshold, the controller 104 determines that the electrical state of the generator 116 is an electrical-pole-slipping-warning electrical state.

[0045] In block 330, controller 104 determines whether the resultant displacement is greater than a displacement threshold. If the resultant displacement (the resultant displacement) is greater than the displacement threshold, controller 104 proceeds to block 345 and determines that the mechanical state of generator 116 is a mechanical-pole-slip state. For example, in one exemplary embodiment, the displacement threshold may be set to a predetermined value (e.g., 4 mm). If the resultant displacement is greater than the predetermined value, controller 104 determines that the mechanical state is a mechanical-pole-slip state. If the resultant displacement is less than or equal to the threshold, the process proceeds to block 335.

[0046] In block 335, the controller 104 determines whether the resultant displacement is greater than a displacement warning threshold. If the resultant displacement is greater than the displacement warning threshold, the controller 104 proceeds to block 345 and determines that the mechanical state of the generator 116 is a mechanical-pole-slip-warning mechanical state. If the resultant displacement is less than or equal to the displacement warning threshold, the controller 104 proceeds to block 345 and determines that the mechanical state of the generator 116 is a mechanical-no-pole-slip mechanical state. For example, in one exemplary embodiment, the displacement warning threshold may be set to a predetermined value (e.g., 2 mm). If the resultant displacement is greater than the predetermined value, the controller 104 determines that the mechanical state is a mechanical-pole-slip-warning mechanical state; otherwise, the controller 104 determines that the mechanical state is a mechanical-no-pole-slip mechanical state. Typically, the value selected for the displacement warning threshold is approximately or slightly less than the lowest resultant displacement value that would be caused by a power swing, but less than the lowest resultant displacement value of the generator 116 that would be caused by pole slip.

[0047] In block 350, the controller 104 determines the operating state of the generator 116 of the generator set 102 based on the fusion (or fusing) of the mechanical state and the electrical state of the generator 116. As used herein, the term fusion or fusing refers to using the mechanical state and the electrical state as inputs to determine the resulting operating state of the generator 116. In some embodiments, the controller 104 may utilize a lookup table, a hash table, or other structure to fuse the mechanical state and the electrical state.

[0048] In one exemplary embodiment, the following logic illustrates an exemplary fusion of the mechanical state of the generator 116 and the electrical state of the generator 116 to determine a resultant operating state of the generator 116 of the genset 102 . Figure 5 The results of this exemplary fusion of the mechanical state of generator 116 and the electrical state of generator 116 to determine a resultant operating state of generator 116 are shown.

[0049] If the mechanical state is mechanical-no-pole-slip and the electrical state is electrical-no-pole-slip, the controller 104 determines that the operating state is no-pole-slip and sets a flag indicating that operating state.

[0050] If the mechanical status is Mechanical-Pole-Slip-Warning and the electrical status is Electrical-No-Pole-Slip, the controller 104 determines that the operational status is No-Pole-Slip and sets a flag indicating this operational status.

[0051] If the mechanical state is Mechanical-Pole-Slip and the electrical state is Electrical-No-Pole-Slip, the controller 104 determines that the operating state is Pole-Slip-Warning and sets a flag indicating this operating state.

[0052] If the mechanical state is Mechanical-No-Pole-Slip and the electrical state is Electrical-Pole-Slip-Warning, the controller 104 determines that the operating state is No-Pole-Slip and sets a flag indicating that operating state.

[0053] If the mechanical state is mechanical-pole-slip-warning and the electrical state is electrical-pole-slip-warning, the controller 104 determines that the operational state is pole-slip-warning and sets a flag indicating that operational state.

[0054] If the mechanical state is mechanical-pole-slip and the electrical state is electrical-pole-slip-warning, the controller 104 determines that the operating state is pole-slip and sets a flag indicating this operating state.

[0055] If the mechanical state is mechanical-no-pole-slip and the electrical state is electrical-pole-slip, the controller 104 determines that the operating state is no-pole-slip and sets a flag indicating that operating state.

[0056] If the mechanical state is mechanical-pole-slip-warning and the electrical state is electrical-pole-slip, the controller 104 determines that the operational state is pole-slip-warning and sets a flag indicating that operational state.

[0057] If the mechanical state is mechanical-pole-slip and the electrical state is electrical-pole-slip, the controller 104 determines that the operating state is pole-slip and sets a flag indicating that operating state.

[0058] In block 355 , when the operating status is determined to be pole-slip-warning or pole-slip, the controller 104 records the operating status in the memory component 134 .

[0059] In block 360 , when the operating status is determined to be pole-slip-warning or pole-slip, controller 104 actuates output member 112 to display a warning and / or emit (e.g., flashing light, audible sound) a warning that generator 116 of genset 102 may be close to experiencing pole slip or may be experiencing pole slip.

[0060] In block 365, the controller 104 activates a protective action. The protective action may be shutting down the genset 102 or generator 116, or isolating the genset 102 or generator 116 from the load 126 (via a circuit breaker, etc.). In some embodiments, but not all embodiments, the generator 116 may be isolated or disconnected from the prime mover 114. The controller 104 may trigger the shutdown or isolation when the operating condition is determined to be a pole slip or after a period of time.

[0061] Generally, the above disclosure finds utility in various applications related to stationary power generation and power generation for vehicles, machines, and / or tools utilizing gensets 102. More specifically, the disclosed systems and methods may be used to provide reliable monitoring and protection of gensets 102 and their loads 126 to minimize adverse effects associated with pole slip on such gensets 102 and loads 126.

[0062] It will be appreciated from the foregoing that although certain embodiments have been described for illustrative purposes, replacements and modifications will be apparent to those skilled in the art from the foregoing description. These and other alternatives are considered equivalent and within the spirit and scope of the present invention and the appended claims.

Claims

1. A system for detecting a magnetic pole slip state in a generator of a generator set, the system comprising: The generator includes a stator and a rotor rotatably disposed within the stator, the generator being configured to rotate a rotor magnetic field in the stator and generate a stator magnetic field when the stator is electrically coupled to a load; as well as a prime mover comprising an output shaft operatively connected to a rotor of the generator, the prime mover being configured to drive rotation of the rotor; as well as a controller in operable communication with the generator set, the controller being configured to: determining a mechanical state based on data related to a translational displacement of the rotor via a displacement sensor; determining an electrical state based on (a) a load angle δ or (b) a load angle δ and a rate of change of the load angle δ associated with rotation of the rotor in the stator; determining an operating state of the generator based on a fusion of the mechanical state and the electrical state; If the operating state is pole-slip-warning, activating the output component to display or issue a warning; as well as If the operating state is Pole-Slip, the protection action is activated.

2. The system of claim 1, wherein the translational displacement comprises a horizontal displacement of the rotor along an x-axis and a vertical displacement of the rotor along a y-axis.

3. The system of claim 1 , wherein the controller is further configured to: If the mechanical state is mechanical-pole-slip-warning and the electrical state is electrical-no-pole-slip, determining a no-pole-slip operating state of the generator; and If the mechanical state is mechanical pole slip and the electrical state is electrical no pole slip, the generator pole slip warning operating state is determined.

4. The system of claim 1 , wherein the controller is further configured to: If the mechanical state is mechanical-no-pole-slip and the electrical state is electrical-pole-slip-warning, determining an operating state of the generator with no-pole-slip; If the mechanical state is mechanical-pole-slip-warning and the electrical state is electrical-pole-slip-warning, determining an operating state of the generator pole-slip-warning; as well as If the mechanical state is mechanical pole slip and the electrical state is electrical pole slip warning, an operating state of the generator pole slip is determined.

5. The system of claim 1 , wherein the controller is further configured to: If the mechanical state is mechanical-no-pole-slip and the electrical state is electrical-pole-slip, determining an operating state of the generator with no-pole-slip; If the mechanical state is mechanical-pole-slip-warning and the electrical state is electrical-pole-slip, determining an operating state of the generator pole-slip-warning; as well as If the mechanical state is mechanical pole slip and the electrical state is electrical pole slip, then the generator pole slip operating state is determined.

6. A method for protecting a generator set from magnetic pole slip, the generator set comprising a prime mover and a generator, the prime mover comprising an output shaft operatively connected to a rotor of the generator, the prime mover being configured to drive rotation of the rotor, the generator comprising a stator and the rotor rotatably disposed within the stator, the stator being electrically coupled to a load, the generator being configured to rotate a rotor magnetic field in the stator and generate a stator magnetic field, the method comprising: determining, by a controller in operable communication with the generator set, a mechanical state of the generator based on data related to the translational displacement of the rotor; calculating, by the controller, a load angle δ and a rate of change of the load angle δ associated with rotation of the rotor in the stator; determining, by the controller, an electrical state of the generator based on (a) the load angle δ or (b) the load angle δ and a rate of change of the load angle δ; determining, by the controller, an operating state of the generator based on a fusion of the mechanical state and the electrical state; If the operating state is pole-slip-warning, activating an output component by the controller to display or issue a warning; as well as If the operating state is pole-slip, a protective action is activated by the controller.

7. The method of claim 6, wherein the translational displacement comprises a horizontal displacement of the rotor along an x-axis, and a vertical displacement of the rotor along a y-axis.

8. The method of claim 7, wherein the translational displacement further comprises a displacement of the rotor along a z-axis. 9 . The method of claim 8 , further comprising calculating a resultant displacement based on the translational displacement, wherein the resultant displacement is used to determine the mechanical state.

10. The method according to claim 6, further comprising: If the mechanical status is mechanical-pole-slip-warning and the electrical status is electrical-no-pole-slip, determining, by the controller in operable communication with the generator set, a no-pole-slip operating state of the generator; as well as If the mechanical state is mechanical pole slip and the electrical state is electrical no pole slip, a pole slip warning operating state of the generator is determined by the controller.

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