A quantitative simulation experimental device for induction motor rotor faults

Abstract

The present invention discloses an experimental device for quantitative simulation of induction motor rotor faults. The device comprises an experimental bench, a rotor lead-out induction motor, and a control cabinet. In the lead-out induction motor, the rotor cage bars are fixed in the slots of the rotor core, and the two ends are respectively installed in the two end ring slots at the two ends. One end of the cage bars has a lead-out screw hole, in which a terminal is installed. Through the conductive and non-conductive nuts on the terminal that contact the end ring, the cage bars can be directly short-circuited or indirectly short-circuited at the end ring B. A number of cage bars can be led out through slip rings and connected to the control cabinet. The present invention fills the gap in a dedicated experimental device for simulating induction motor rotor faults, simplifies the broken bar simulation process, avoids rotor-to-ground short circuits caused by burrs generated by machining, realizes repeatable quantitative simulation of different broken bar fault conditions, and improves the convenience and scalability of induction motor rotor fault testing.

Description

Technical Field

[0001] The invention relates to a comprehensive experimental device for motor faults, in particular to a quantitative simulation experimental device for induction motor rotor faults. Background Art

[0002] As a drive device, induction motors are widely used in defense, industrial production, transportation, infrastructure, agriculture, and everyday life due to their ease of manufacture, low cost, excellent performance, and ease of use. Currently, induction motors are the most widely used and widely used motors worldwide. Therefore, extending the service life of asynchronous induction motors and thereby improving the reliability and stability of the entire production system has become a top priority for industrial development.

[0003] Induction motors are affected by factors such as the power supply, load characteristics, operating mechanism, and installation environment. During operation, the development of faults is a multi-physics coupled, real-time transient process involving electrical, magnetic, thermal, mechanical, and chemical stresses. The most common faults in induction motors include stator winding turn-to-turn short circuits, rotor bar and end ring fractures, bearing wear, and air gap eccentricity. Rotor failure is the most common fault type, accounting for approximately 20% of all fault types and over 70% of the frequency. Effectively diagnosing and preventing rotor failures is a key measure to further improve the reliability of industrial production across all sectors.

[0004] Currently, induction motor maintenance typically involves post-repair and periodic overhauls. Post-repair can result in significant economic losses and poses immeasurable risks when a fault occurs. While periodic overhauls can provide some preventative benefits, their scope is often limited, potentially leading to missed inspections of existing hazards and even the introduction of new safety issues due to disassembly and reassembly. Furthermore, overhauling a safely operating motor consumes significant manpower, material resources, financial resources, and time, resulting in indirect economic losses. Therefore, real-time safety assessment and fault prediction of operating induction motors can truly address the bottleneck of motor fault diagnosis. Real-time fault diagnosis of induction motor rotors is of vital economic and social significance.

[0005] When a motor fails, the cause is often determined based on engineering experience. This neither allows for a scientific and effective solution to the problem nor facilitates the commercialization of diagnostic methods. Therefore, it is crucial to couple multiple physical fields and establish a comprehensive experimental platform for induction motor fault simulation testing.

[0006] The primary rotor failure in induction motors is squirrel-cage bar breakage. Currently, the primary method for simulating rotor bar breakage in experimental setups for induction motor fault research is bar cutting. This method is complex and tedious, and can easily produce burrs that can cause rotor-to-ground shorts. Furthermore, it cannot simulate faults such as gradual bar breakage and thinning, and the damage to the rotor structure is irreversible. Summary of the Invention

[0007] The purpose of the present invention is to solve the deficiencies in the existing induction motor rotor fault simulation technology and to propose an induction motor rotor fault simulation experimental device to achieve adjustable and repeatable quantitative research on rotor broken bars.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] The invention comprises an experimental bench, a rotor-extracted induction motor and a control cabinet, and is characterized in that the rotor-extracted induction motor and the control cabinet are both installed on the experimental bench, and the extraction-type induction motor is electrically connected to the control cabinet.

[0010] The casing includes a slip ring cover, a front end cover, a middle part of the casing and a rear end cover which are arranged in sequence along the axial direction. The two ends of the middle part of the casing are respectively fixed to the front end cover and the rear end cover. The slip ring cover is fixed to the outer end of the front end cover. The slip ring is placed in the slip ring cover. The stator is fixed in the middle part of the casing. The lead-out rotor is placed in the stator and connected to the slip ring.

[0011] The rotor-extracted induction motor comprises four parts: an extracting rotor, a slip ring, a stator and a casing. The extracting rotor, the slip ring and the stator are all installed in the casing.

[0012] The lead-out rotor includes a rotating shaft, a rotor core, squirrel cage bars, end rings A and end rings B; the rotating shaft passes through the rotor core and is fixed, bearings are fixed at both ends of the rotating shaft, the outer peripheral surface of the rotor core is provided with multiple strip grooves evenly distributed along the circumferential direction, and end rings A and end rings B are respectively provided at both ends of the rotor core, the middle part of the squirrel cage bars is fixed in the strip grooves of the rotor core, and the two ends of the squirrel cage bars are respectively installed in the slots of end rings A and end rings B; the end rings A and end rings B are both made of conductive materials.

[0013] In the lead-out rotor, one end of each squirrel cage bar is mounted on the end ring B closest to the slip ring, and the portion in contact with the end ring B is covered with a heat-resistant rubber sleeve. The heat-resistant rubber sleeve prevents direct electrical connection between the squirrel cage bar and the end ring B. The other end of each squirrel cage bar is mounted on the end ring A away from the slip ring, and is directly electrically connected to the portion in contact with the end ring B.

[0014] Each squirrel cage guide bar is provided with a lead-out screw hole at the end face close to the slip ring, in which a terminal is installed. A nut or a gasket is installed at the terminal terminal in close contact with the end ring B close to the slip ring.

[0015] The slip ring includes a conductive ring and a brush; the dynamic guide bar lead wire on the conductive ring is selectively electrically connected to the terminal, so that the dynamic guide bar lead wire is selectively electrically connected to the squirrel cage guide bar through the terminal; the weak current lead wire on the conductive ring is electrically connected to the rotor temperature sensor; the brush is provided with a lead wire, and the dynamic guide bar lead wire and the weak current lead wire are both electrically connected to the lead wire on the brush, and are electrically connected to the control cabinet through the lead wire on the brush.

[0016] The materials of the nut or gasket installed on the terminal are divided into two types: conductive material and non-conductive material. By adjusting the conductivity and non-conductivity of the nut or gasket, the terminal and the end of the squirrel cage conductor are electrically connected or not electrically connected to the end ring B, so that the squirrel cage conductor connected to the terminal is short-circuited or not short-circuited.

[0017] When the nut or washer is made of conductive material, the cage bars are electrically connected to the end ring B via the terminal, and the ends of the cage bars electrically connected to the end ring B are electrically connected together via the end ring B, and the cage bars at the nut or washer are short-circuited.

[0018] When the nut or washer is made of non-conductive material, the cage bars cannot be electrically connected to the end ring B via the terminal, the dynamic bar lead wire is electrically connected to the cage bars via the terminal, and the cage bars at the nut or washer are not short-circuited.

[0019] The slip ring cover is provided with a lead-out groove, and the electrical connection line between the lead-out column on the slip ring brush and the control cabinet passes through the lead-out groove to realize the connection between the lead-out column and the control cabinet.

[0020] The control cabinet includes a power resistor module and a signal module that are electrically connected to each other. All lead posts connected to the moving conductor lead wires are electrically connected at the same connection point through the power resistor module. A resistor is provided in the power resistor module, and the resistor is connected in series between the squirrel cage conductors led out through the moving conductor lead wires and the lead posts and the above-mentioned connection points.

[0021] 2. A quantitative simulation method for rotor faults:

[0022] In this way, the present invention can lead the squirrel cage bars that were originally short-circuited through the end ring B to the power resistor module through the moving bar lead-out wires, the terminal and the slip ring instead of short-circuiting through the end ring B. By adjusting the connection method of the moving bar lead-out wires and the resistance of the power resistor module, quantitative simulation of the number and degree of rotor broken bar faults can be achieved.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The comprehensive experimental device of the present invention fills the gap in the special experimental device for simulating induction motor rotor faults. Compared with the traditional punching method to simulate broken bars, the processing technology is simpler and the rotor short circuit caused by burrs generated during processing is avoided.

[0025] (2) By adjusting the resistance value and wiring method of the rotor external power resistor module, repeatable quantitative simulation of fault conditions such as thin bars, gradually broken bars, complete broken bars, and different broken bar positions is achieved.

[0026] (3) The terminal at end ring B is first adjusted by adjusting the gasket or nut on it to adjust the center of mass position to ensure the dynamic balance of the rotor; secondly, the direct and indirect connection between the squirrel cage bars and the end ring is achieved through conductive and non-conductive nuts; finally, the axial tightening force is used to further prevent the bars from moving in the rotor core slots, ensuring the reliability of the rotor structure.

[0027] (4) By using the end cap, guide bar lead wire and slip ring with special structure, the internal signals of the motor (such as rotor electrical signal, rotor temperature signal, etc.) can be obtained in real time without repeatedly disassembling and assembling the casing, which improves the convenience of studying the rotor fault of the induction motor.

[0028] (5) The signal module realizes the real-time acquisition of characteristic signals under different fault conditions, which can be used for research on fault monitoring, control strategies, etc., making the experimental device highly scalable. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the overall structural diagram of the experimental device described in the present invention.

[0030] Figure 2 This is an exploded view of the rotor-extracted induction motor according to the present invention.

[0031] Figure 3 Schematic diagram of the rotor structure of the induction motor according to the present invention.

[0032] Figure 4 Schematic diagram of the slip ring structure of the induction motor of the present invention.

[0033] Figure 5 Schematic diagram of the casing structure of the induction motor of the present invention.

[0034] Figure 6 The figure is a schematic diagram of the manufacturing process of the induction motor rotor according to the present invention.

[0035] Legend: 1. Experimental bench; 2. Rotor-lead-out induction motor; 3. Control cabinet; 21. Lead-out rotor; 22. Slip ring; 23. Stator; 24. Casing; 211. Rotating shaft; 212. End ring B; 213. End ring A; 214. Rotor core; 215. Squirrel cage guide bar; 216. Bearing; 217. Terminal; 218. Heat-resistant rubber sleeve; 219. Lead-out screw hole; 221. Brush; 222. Conductive ring; 223. Lead post; 224. Weak-current lead wire; 225. Temperature sensor; 226. Moving guide bar lead wire; 241. Front cover; 242. Slip ring cover; 243. Lead-out slot; 244. Middle part of casing; 245. Rear cover. DETAILED DESCRIPTION

[0036] In order to describe the present invention more specifically, the technical solution of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] In the description of the present invention, it should be noted that directional words such as the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., which indicate directions and positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and should not be understood as limiting the specific scope of protection of the present invention.

[0038] like Figure 1 As shown, the device includes a test bench 1, a rotor-extracted induction motor 2 and a control cabinet 3. The device is characterized in that the rotor-extracted induction motor 2 and the control cabinet 3 are both installed on the test bench 1. The test bench 1 is used to support and fix the rotor-extracted induction motor 2 and provide a load; the rotor-extracted induction motor 2 is electrically connected to the control cabinet 3, and the control cabinet 3 is used to realize quantitative simulation of rotor faults and signal acquisition and processing.

[0039] like Figure 5 As shown, the casing 24 includes a slip ring cover 242, a front end cover 241, a casing middle portion 244 and a rear end cover 245 which are arranged in sequence along the axial direction. The two ends of the casing middle portion 244 are fixed to the front end cover 241 and the rear end cover 245 respectively. The slip ring cover 242 is fixed to the outer end of the front end cover 241. The slip ring 22 is placed in the slip ring cover 242. The stator 23 is fixed in the casing middle portion 244. The lead-out rotor 21 is placed in the stator 23 and connected to the slip ring 22.

[0040] like Figure 2-Figure 5 As shown, the rotor-extracted induction motor 2 includes four parts: an extracted rotor 21 , a slip ring 22 , a stator 23 and a casing 24 . The extracted rotor 21 , the slip ring 22 and the stator 23 are all installed in the casing 24 .

[0041] like Figure 3 As shown, the lead-out rotor 21 includes a shaft 211, a rotor core 214, squirrel cage bars 215, end rings A 213 and B 212; the shaft 211 passes through the rotor core 214 and is fixed, and bearings 216 are fixed at both ends of the shaft 211. The two ends of the shaft 211 are respectively mounted on the front cover 241 and the rear cover 245 through the bearings 216. In the central through hole of the rotor core 214, a plurality of strip grooves are evenly distributed along the circumferential direction on the outer peripheral surface thereof, and each strip groove is arranged approximately in the axial direction but not completely parallel to the axial direction. An end ring A213 and an end ring B212 are respectively provided at both ends of the rotor core 214. The end ring A213 and the end ring B212 are respectively spaced apart from the rotor core 214 along the axial direction. A plurality of strip grooves are evenly distributed along the circumferential direction on the outer peripheral surface thereof, and the middle part of the squirrel cage guide bar 215 is fixed in the strip groove of the rotor core 214, and the two ends of the squirrel cage guide bar 215 are respectively installed in the slots of the end ring A213 and the end ring B212; the end ring A213 and the end ring B212 are both made of conductive material.

[0042] In the lead-out rotor 21, each cage bar 215 is mounted on one end of the end ring B212 near the slip ring 22, and the portion in contact with the end ring B212 is covered with a heat-resistant rubber sleeve 218. The heat-resistant rubber sleeve 218 prevents direct electrical connection between the cage bar 215 and the end ring B212. Each cage bar 215 is mounted on one end of the end ring A213 away from the slip ring 22, and is directly electrically connected to the portion in contact with the end ring B212.

[0043] Each cage bar 215 has a lead-out screw hole 219 on its end near the slip ring 22. A terminal 217 is mounted in this lead-out screw hole 219. A nut or washer is installed where the terminal 217 abuts against the end ring B 212 near the slip ring 22. The terminal 217 and the cage bar 215 are both made of metal and form an electrical connection.

[0044] The end ring B212 and the squirrel cage guide bar 215 are initially fixed by interference fit and further fixed by the terminal 217.

[0045] like Figure 4 As shown, the slip ring 22 includes a conductive ring 222 and a brush 221 connected to each other. The conductive ring 222 is provided with a moving conductor lead 226 and a weak current lead 224.

[0046] The plurality of moving conductor lead wires 226 on the conductive ring 222 are selectively electrically connected to the terminal 217, so that the moving conductor lead wires 226 are selectively electrically connected to the squirrel cage conductor 215 through the terminal 217;

[0047] The weak current lead wire 224 on the conductive ring 222 is electrically connected to the rotor temperature sensor 225;

[0048] The brush 221 is provided with a lead post 223, and the dynamic conductor lead wire 226 and the weak current lead wire 224 are both connected to the lead post 223 on the brush 221, and are electrically connected to the power resistor module 31 and the signal module 32 in the control cabinet 3 through the lead post 223 on the brush 221.

[0049] The materials of the nut or gasket installed on the terminal 217 are divided into two types: conductive material and non-conductive material. By adjusting the conductivity and non-conductivity of the nut or gasket, the terminal 217 and the end of the squirrel cage conductor 215 are electrically connected or not electrically connected to the end ring B212, so that the squirrel cage conductor 215 connected to the terminal 217 is short-circuited or not short-circuited.

[0050] When the nut or washer is made of conductive material, the cage bars 215 are electrically connected to the end ring B212 via the terminal 217. The ends of the cage bars 215 electrically connected to the end ring B212 are electrically connected together via the end ring B212. The cage bars 215 at the nut or washer are short-circuited.

[0051] When the nut or gasket is made of non-conductive material, the cage conductor 215 cannot be electrically connected to the end ring B212 via the terminal 217, and the dynamic conductor lead 226 is electrically connected to the cage conductor 215 via the terminal 217. The cage conductor 215 at the nut or gasket is not short-circuited, but is connected to the resistance of the power resistor module 31 in the control cabinet 3 via the dynamic conductor lead 226.

[0052] The number of the moving conductor lead wires 226 and the number of the cage conductor bars 215 may be different. The number of the moving conductor lead wires 226 and the number of the cage conductor bars 215 that need not be short-circuited are the same.

[0053] In this way, the gaskets that are in close contact with the terminal 217 and the end ring B212 are divided into two categories, which are made of conductive materials and non-conductive materials respectively, so as to respectively achieve short-circuiting and disconnection of the conductive bar at the end ring B212.

[0054] The nut of the terminal 217 has two functions: one is to fix the dynamic guide bar lead wire 226, and the other is to adjust the dynamic balance of the rotor.

[0055] like Figure 5 As shown, the slip ring cover 242 is provided with a lead-out slot 243 , and the electrical connection line between the lead-out post 223 on the brush 221 of the slip ring 22 and the control cabinet 3 passes through the lead-out slot 243 to achieve the connection between the lead-out post 223 and the control cabinet 3 .

[0056] The control cabinet 3 includes an electrically connected power resistor module 31 and a signal module 32. The lead pins 223 are electrically connected via the power resistor module 31 and the signal module 32. The power resistor module 31 is used to quantitatively simulate rotor faults, while the signal module 32 is used to collect and process signals, including rotor electrical signals. All lead pins 223 connected to the moving bar lead wires 226 are electrically connected at a common connection point via the power resistor module 31. The power resistor module 31 includes a resistor, which is connected in series to the circuit between the cage bars 215, which are connected via the moving bar lead wires 226 and the lead pins 223, and the aforementioned connection point.

[0057] In a specific implementation, a plurality of resistors are provided, and each resistor is used to connect to a corresponding squirrel cage conductor bar 215 .

[0058] refer to Figure 6 The embodiment of the present invention provides a manufacturing process of an extraction type rotor 21, comprising the following steps:

[0059] (1) Manufacturing the rotor core 214: Using a stamping die, a silicon steel plate is punched out with an axis hole and a plurality of guide bar holes to form a stamped silicon steel sheet, and each stamped silicon steel sheet is laminated with a dummy shaft to manufacture the rotor core 214, such as Figure 6 (a);

[0060] (2) Manufacturing the cage guide bar 215: The cage guide bar 215 is manufactured by cold drawing process, and an M6 lead-out screw hole 219 is drilled at one end;

[0061] (3) Inserting the bars: After fixing the rotor core 214 with a positioning fixture, insert the cage bars 215 into the bar slots of the rotor core 214 one by one. Figure 6 (b)

[0062] (4) Manufacturing end rings A213 and B212: End rings A213 and B212 are manufactured using a pure copper powder metallurgy process. Through grooves corresponding to the rotor core guide bar holes are reserved on end rings A213 and B212, and a draft angle of 3-4° is set on the inner walls around the through grooves to increase the connection strength and conductive area between end rings A213 and B212 and the cage guide bars 215;

[0063] (6) Specifically, after the end ring A213, the end ring B212 and the squirrel cage conductor 215 are manufactured, they are subjected to surface descaling and silver plating to reduce contact resistance and increase electrical conductivity;

[0064] (7) Install the heat-resistant rubber sleeve 218: Put the heat-resistant rubber sleeve 218 with an axial length greater than the end ring B212 on the end of the squirrel cage guide bar 215 with the lead-out screw hole 219. After installing the heat-resistant rubber sleeve 218, the assembly is as follows: Figure 6 (c)

[0065] (8) Install the end ring A213: Insert the ends of the squirrel cage guide bars 215 without screw holes into the corresponding through slots of the end ring A213 one by one, use induction heating to rivet them together, and then use argon arc welding to further strengthen the end hook seams;

[0066] (9) Install the end ring B212: Insert the ends of the squirrel cage guide bars 215 with the lead screw holes 219 into the corresponding slots of the end rings B212 one by one. Under the premise of ensuring that the end rings B212 are only in contact with the heat-resistant rubber sleeves 218, use induction heating to rivet them together. After installing the end rings at both ends, the assembly is as follows Figure 6 (d)

[0067] (10) Install the terminal 217: Install the nut, washer and screw one by one in the lead-out screw hole 219. The nut to be installed on the squirrel cage bar 215 that needs to be short-circuited directly at the end ring B212 is made of conductive material, and the nut to be installed on the squirrel cage bar 215 for introducing rotor faults is made of non-conductive material. The above nuts can contact the end faces of the squirrel cage bar 215 and the end ring B212 at the same time. The assembly after installing the terminal 217 is as follows: Figure 6 (d)

[0068] (11) Remove the dummy shaft: remove the rotor core from the dummy shaft and replace it with the real shaft 211;

[0069] (12) Finishing: Finish turning the outer circle of the rotor and checking the coaxiality of the end ring at the same time;

[0070] (13) Dynamic balance: The residual unbalance is required to be no more than 0.3g. The unbalance is adjusted by adding weight. The nuts and gaskets fixed on the terminal 217 are adjusted. The finished lead-out rotor 21 is as shown in the figure. Figure 6 (f) shown.

[0071] The specific method of use of the present invention is as follows:

[0072] (1) Install the test bench. Fix the assembled rotor-extracted induction motor 2 to the bracket of the test bench 1, and align and connect the load to the rotor-extracted induction motor 2 through a coupling.

[0073] (2) Setting the fault state. Adjust the connection mode of the static conductor lead wire and the resistance value of the power resistor module 31 to achieve quantitative simulation of fault conditions such as thin conductor, gradual broken conductor, complete broken conductor, and different broken conductor positions.

[0074] (3) Motor operation and stop. Set the operating parameters of the rotor-extracted induction motor 2 and power on to start the motor. During operation, the signal module 32 will continuously sample and process the motor signal. After the motor has run for a period of time, power off to stop the motor.

[0075] (4) Subsequent processing and research: The results of the signal module 32 are read by the host computer for subsequent processing and research.

[0076] Therefore, the present invention fills the gap in the dedicated experimental device for simulating induction motor rotor faults, simplifies the broken bar simulation process, avoids the rotor-to-ground short circuit caused by burrs generated by processing, realizes repeatable quantitative simulation of different broken bar fault conditions, and improves the convenience and scalability of induction motor rotor fault testing.

[0077] The above description of the embodiments is intended to facilitate understanding and application of the present invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to the above embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention should fall within the scope of protection of the present invention.

Claims

1. A quantitative simulation experimental device for induction motor rotor fault, characterized in that: The invention comprises an experimental bench (1), a rotor-extracted induction motor (2) and a control cabinet (3), wherein the rotor-extracted induction motor (2) and the control cabinet (3) are both mounted on the experimental bench (1), and the rotor-extracted induction motor (2) is electrically connected to the control cabinet (3); The rotor-extracted induction motor (2) comprises four parts: an extracting rotor (21), a slip ring (22), a stator (23) and a casing (24); the extracting rotor (21), the slip ring (22) and the stator (23) are all installed in the casing (24); In the lead-out rotor (21), one end of each squirrel cage conductor (215) is mounted on the end ring B (212) close to the slip ring (22), and the contact portion of the end ring B (212) is covered with a heat-resistant rubber sleeve (218). The heat-resistant rubber sleeve (218) prevents direct electrical connection between the squirrel cage conductor (215) and the end ring B (212). One end of each squirrel cage conductor (215) is mounted on the end ring A (213) away from the slip ring (22), and the contact portion of the end ring B (212) is directly electrically connected. Each squirrel cage conductor (215) is provided with a lead-out screw hole (219) on the end surface close to the slip ring (22), and a terminal (217) is mounted in the lead-out screw hole (219). A nut or a gasket is mounted on the terminal (217) at a position close to the end ring B (212) close to the slip ring (22). The material of the nut or gasket installed on the terminal (217) is divided into two types: conductive material and non-conductive material. By adjusting the conductivity and non-conductivity of the nut or gasket, the terminal (217) and the end of the squirrel cage conductor (215) are electrically connected or not electrically connected to the end ring B (212), so that the squirrel cage conductor (215) connected to the terminal (217) is short-circuited or not short-circuited; The control cabinet (3) includes a power resistor module (31) and a signal module (32) electrically connected to each other, and all lead posts (223) connected to the moving guide bar lead wire (226) are electrically connected at the same connection point through the power resistor module (31), wherein a resistor is provided in the power resistor module (31), and the resistor is connected in series between the squirrel cage guide bar (215) led out through the moving guide bar lead wire (226) and the lead post (223) and the above-mentioned connection point; The signal module (32) is used to realize signal acquisition and processing including rotor electrical signals and rotor temperature signals; The power resistor module (31) is used to realize quantitative simulation of rotor faults, and the squirrel cage conductors (215) originally connected by short circuit through the end ring B (212) are led out to the resistance of the power resistor module through the moving conductor lead wire (226), the lead column (223) and the slip ring (22), and the connection mode of the moving conductor lead wire and the resistance value of the power resistor module are adjusted to realize quantitative simulation of rotor broken bar faults in terms of the number and degree of fault conditions such as thin bars, gradual broken bars, complete broken bars, and different broken bar positions.

2. The induction motor rotor fault quantitative simulation experimental device according to claim 1, characterized in that: The casing (24) includes a slip ring cover (242), a front end cover (241), a casing middle part (244) and a rear end cover (245) which are sequentially arranged in an integral manner along the axial direction. The two ends of the casing middle part (244) are respectively fixed to the front end cover (241) and the rear end cover (245). The slip ring cover (242) is fixed to the outer end of the front end cover (241). The slip ring (22) is placed in the slip ring cover (242). The stator (23) is fixed in the casing middle part (244). The lead-out rotor (21) is placed in the stator (23) and connected to the slip ring (22).

3. The induction motor rotor fault quantitative simulation experimental device according to claim 1, characterized in that: The lead-out rotor (21) comprises a rotating shaft (211), a rotor core (214), a squirrel cage guide bar (215), an end ring A (213) and an end ring B (212); the rotating shaft (211) passes through the rotor core (214) and is fixed, bearings (216) are fixed at both ends of the rotating shaft (211), a plurality of strip grooves are uniformly distributed along the circumferential direction on the outer peripheral surface of the rotor core (214), an end ring A (213) and an end ring B (212) are respectively provided at both ends of the rotor core (214), the middle portion of the squirrel cage guide bar (215) is fixed in the strip groove of the rotor core (214), and the two ends of the squirrel cage guide bar (215) are respectively installed in the slots of the end ring A (213) and the end ring B (212); the end ring A (213) and the end ring B (212) are both made of conductive material.

4. The induction motor rotor fault quantitative simulation experimental device according to claim 1, characterized in that: The slip ring (22) comprises a conductive ring (222) and a brush (221); the moving guide bar lead wire (226) on the conductive ring (222) is selectively electrically connected to the terminal (217), so that the moving guide bar lead wire (226) is selectively electrically connected to the squirrel cage guide bar (215) through the terminal (217); the weak current lead wire (224) on the conductive ring (222) is electrically connected to the rotor temperature sensor (225); a lead wire (223) is provided on the brush (221), and the moving guide bar lead wire (226) and the weak current lead wire (224) are both electrically connected to the lead wire (223) on the brush (221), and are electrically connected to the control cabinet (3) through the lead wire (223) on the brush (221).

5. The induction motor rotor fault quantitative simulation experimental device according to claim 4, characterized in that: When the nut or washer is made of conductive material, the cage conductor (215) is electrically connected to the end ring B (212) via the terminal (217), and the ends of the cage conductors (215) electrically connected to the end ring B (212) are electrically connected together via the end ring B (212), and the cage conductors (215) at the nut or washer are short-circuited; When the nut or washer is made of non-conductive material, the cage conductor (215) cannot be electrically connected to the end ring B (212) via the terminal (217), the dynamic conductor lead (226) is electrically connected to the cage conductor (215) via the terminal (217), and the cage conductor (215) at the nut or washer is not short-circuited.

6. The induction motor rotor fault quantitative simulation experimental device according to claim 2, characterized in that: The slip ring cover (242) is provided with a lead-out groove (243), and an electrical connection line between the lead-out column (223) on the brush (221) of the slip ring (22) and the control cabinet (3) passes through the lead-out groove (243) to achieve connection between the lead-out column (223) and the control cabinet (3).

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