Method for heating coil component, system for heating coil component and method for manufacturing electric machine
Through the connection between constant power DC power supply and coil windings and real-time power control, the problems of uneven heat and high energy consumption in conductive and induction heating are solved, and efficient, uniform heating and precise temperature control of coil components are achieved, ensuring insulation The quality of the processing and the stability and economicality of the system.
Patent Information
- Application Number
- CN201910992422.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2019-10-18
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2039-10-18
AI Technical Summary
Existing methods for heating coil components, such as conduction heating and induction heating, have problems such as uneven heat transfer, high energy consumption, complex equipment and difficult to control temperature, which affects the uniformity of the paint layer for subsequent insulation treatment.
The constant power DC power supply is connected to the coil winding. By controlling the power output power, DC current is provided to heat the coil components, and the current and voltage data are collected in real time through the detection terminal to correct the output power to achieve accurate control of the target temperature.
It realizes efficient and uniform heating of coil components, reduces energy waste, improves temperature control accuracy and heating speed, ensures high-quality paint layer for subsequent insulation treatment, and is stable and cost-effective in the system.
Smart Images
Figure CN112688510B_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of motor manufacturing. Specifically, the present application relates to a method for heating a coil component, a system for heating a coil component and a method for manufacturing a motor. Background Art
[0002] The process of insulating the coil winding includes dripping paint, dipping paint and other processes. For example, in the motor manufacturing process, the coil winding of the motor rotor or stator is first preheated, and then the insulation treatment is carried out, that is, the resin is introduced to cover the surface of the coil to form a paint layer, and finally solidified. The preheating step is to drive away moisture in the coil and keep the coil at a high temperature to facilitate the subsequent resin impregnation. When the temperature rises to a certain level and the resistance of the coil remains constant, the preheating step is completed.
[0003] The preheating step can be performed using a variety of heating methods. Currently, conduction heating using air or other media, or induction heating, is commonly used. In the first heating method, a medium (such as air) is used to transfer energy. Usually, the rotor or stator of the motor is placed in a warm chamber or furnace and reaches a set temperature after a period of heating. In another heating method, a set of electromagnetic induction equipment is used to generate current in the object being heated to generate heat energy. The equipment includes at least an induction coil, an AC power supply, and a cooling element.
[0004] For conduction heating, since a medium is used to transfer heat energy, a longer heating time and related equipment are required. The temperature chamber or furnace is large in volume, which causes some heat loss and requires more energy consumption. Another problem with the large volume is the uneven flow of the medium, resulting in uneven temperature distribution. In addition, the internal temperature of the heated object is difficult to obtain. Energy transfer has a lag, so this method is generally inefficient.
[0005] The problem with induction heating is that, first of all, the electromagnetic induction equipment is complex. Secondly, the coil temperature is difficult to determine by physical methods, and there is also temperature non-uniformity. This non-uniformity will affect the subsequent step of introducing the resin, and the resin will have difficulty forming a uniform paint layer on the coil. Summary of the invention
[0006] One aspect of the technical problem to be solved by the present application is to provide a method for heating a coil component of a motor during a motor manufacturing process.
[0007] The method comprises connecting the coil winding of the coil component to a constant power DC power supply to provide a DC current to the coil winding, wherein during the power supply process, the output power of the constant power DC power supply is controlled to heat the coil component.
[0008] In an embodiment of the heating method, a command is transmitted to the constant power DC power supply via a control interface provided on the constant power DC power supply to control the output power of the constant power DC power supply.
[0009] In an embodiment of the heating method, a power output terminal and a detection terminal provided on the constant power DC power supply are respectively contacted with the component, and current and voltage are obtained through the detection terminal.
[0010] In one embodiment of the heating method, the output power of the constant power DC power supply is corrected based on the current and the voltage.
[0011] In an embodiment of the heating method, the output power of the constant power DC power supply is controlled so that the power value of the output power gradually decreases until the heating ends.
[0012] In one embodiment of the heating method, the maximum current provided by the constant-power DC power supply to the coil winding is not less than 120A, the inductance generated by the coil winding is not greater than 6.25mH, and the time period for the output power to gradually decrease is not less than 1.5s.
[0013] In one embodiment of the heating method, when the coil component is a rotor, the constant power DC power supply is connected to the coil winding in a diagonal manner via the commutator of the rotor; when the coil component is a stator, the constant power DC power supply is directly connected to the coil winding of the stator.
[0014] Another aspect of the present application is to provide a system for heating a coil component, comprising:
[0015] a constant power DC power supply, the constant power DC power supply being configured to be connected to a coil winding of the coil component to be heated so as to provide a DC current to the coil winding; and
[0016] A controller is configured to be connected to the constant power DC power supply to control the output power of the constant power DC power supply so as to heat the coil component.
[0017] In one embodiment of the above system, the constant power DC power supply has a control interface, and the controller is connected to the constant power DC power supply via the control interface to transmit instructions to the constant power DC power supply to control the output power of the constant power DC power supply.
[0018] Another aspect of the present application is to provide a method for manufacturing a motor. The method comprises the following steps:
[0019] Providing a component wound with a coil;
[0020] heating the component by the method described above; and
[0021] The coils of the components are insulated.
[0022] Compared with the existing heating technology, the method of the present application can directly heat the coil on the motor component, and the temperature is controlled by a suitable measurement system. Therefore, the heating temperature required for the subsequent insulation treatment can be accurately obtained, and the error range of the heating temperature is very small. As a result, a high-quality paint layer in terms of thickness and uniformity can be obtained.
[0023] Energy is directly provided to the components through the power supply, so there is no energy loss, which reduces waste. Moreover, through this heating method of the present application, it can be heated to the set temperature in a short time (compared to, for example, conduction heating takes tens of minutes).
[0024] The whole heating system is stable and the accuracy is improved. The temperature can be quickly obtained through the current resistance value and the target resistance value, and the resistance value can be calculated from the collected data. This is conducive to closed-loop control.
[0025] The entire heating system only requires a power supply and related electronic equipment, and utilizes the coil to energize to perform self-heating of the motor components. It does not require a large temperature chamber, temperature measuring instrument, heating actuator and cooling equipment, so it is cost-effective.
[0026] Other aspects and features of the present application will become apparent from the following detailed description with reference to the accompanying drawings. It should be understood, however, that the drawings are designed for illustrative purposes only and are not intended to limit the scope of the present application, as reference should be made to the appended claims. It should also be understood that the drawings are intended only to conceptually illustrate the structures and processes described herein and, unless otherwise indicated, are not necessarily drawn to scale. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present application will be more fully understood by referring to the following detailed description of specific embodiments in conjunction with the accompanying drawings, in which the same reference numerals in the drawings always refer to the same elements in the drawings.
[0028] Figure 1 is a schematic diagram of a system for heating a motor involved in the present application;
[0029] Figure 2 A flow chart of a method for heating a component of a motor according to the present application;
[0030] Figure 3 A flowchart of a method for manufacturing a motor involved in the present application;
[0031] Figure 4 This is a schematic diagram of the motor's rotor at the scene;
[0032] Figure 5 A flow chart for heating a rotor of an electric machine according to the method of the present application;
[0033] Figure 6 Based on Figure 5 A diagram showing the relationship between temperature and heating time established by the method;
[0034] Figure 7 Based on Figure 5 Schematic diagram of the curve of the relationship between output power and heating time established by the method. DETAILED DESCRIPTION
[0035] In order to help those skilled in the art to accurately understand the subject matter for which protection is sought in the present application, the specific implementation of the present application is described in detail below in conjunction with the accompanying drawings.
[0036] The method involved in the present application is used for the process of insulating the coil winding during the motor manufacturing process. The method of the present application is a pretreatment step of the process and can be used for the stator and rotor of the motor wound with the coil. Here, the process of insulating the coil winding includes the known paint dripping process or the paint dipping process, for example but not limited to, the rotor is placed in the paint dripping equipment and rotated at a high speed, and the paint dripping equipment pours the paint (such as resin) on the coil winding of the rotor, and the paint penetrates into the coil winding by its own weight, so as to form a paint layer on the coil winding. This process can improve the electrical strength, mechanical strength, moisture resistance and chemical stability of the coil winding.
[0037] In the existing insulation process, taking the rotor as an example, the rotor with the wound coil is first placed in a warm chamber, then heated by conduction using air, and then subjected to a paint dripping process, and finally dried and cooled to solidify the paint.
[0038] Figure 1 A schematic diagram of a system for heating a coil component of a motor according to the present application is shown. The system includes a constant power DC power supply and a controller. The constant power DC power supply is connected to a coil winding of a coil component of a motor to be heated, not shown, to supply power to the coil winding, thereby heating the component of the motor. The controller is connected to the constant power DC power supply to control the output power of the constant power DC power supply so that the component of the motor is heated at a target temperature.
[0039] Here, a constant power DC power supply is a power-controlled power supply that outputs DC power. Compared with other types of power supplies that output a stable voltage or current, a constant power DC power supply can control the power output during the power supply process instead of controlling the voltage or current. Figure 1As shown, it has a control interface, and the controller is connected to a constant power DC power supply, such as a control unit in the power supply, via the control interface. Through the control interface, the peripheral controller transmits instructions to the internal control unit to control the output power of the power supply. The constant power DC power supply has a power output terminal and a detection terminal, and the power output terminal is connected to the coil component of the motor to be heated. The parameters reflecting the heating state of the coil component of the motor can be obtained through the detection terminal.
[0040] Figure 2 The heating process involved in the present application is shown. The rotor is used as the heating object. At frame 101, the rotor is connected to the power output terminal of the constant power DC power supply so that the power supply can supply power to the rotor. When the power supply is powered on, the current passes through the rotor to form a power supply loop. The coil winding can be regarded as a resistor, and the current passes through the resistor to generate a thermal effect, thereby heating the rotor.
[0041] At block 102, parameter data of the rotor in the power-on state is collected. The data may be data in a detection circuit for the rotor, or data in a circuit where the rotor is located. The data may be obtained by a monitoring unit carried by the power supply itself, or by one or more detection instruments. The data to be collected may be one or more, for example but not limited to, data including current, voltage, etc. The resistance value of the coil winding of the rotor may be obtained from these collected data.
[0042] Based on the current and voltage values, the actual temperature of the rotor can be known. The actual temperature of the rotor can be obtained and recorded in real time. In the rotor heating process, it is not the case that the higher the heating temperature, the better, nor is it the case that the faster the temperature rise, the better. The ideal heating state is to heat to a certain temperature, and the heating state is stable, including what the rotor temperature is when stable, how long the stable time is, and the heating cannot be too fast. These heating requirements of the rotor can come from customer requirements or industry standards and specifications, or be formulated according to the physical properties of the rotor. Based on these heating requirements, a target heating curve for the rotor can be drawn up, such as a time-temperature curve, which can reflect the target heating time of the rotor, the target temperature when the heating is completed, and how long it takes to reach the target temperature. Correspondingly, a curve of the output power of a constant power DC power supply that changes with time can also be drawn up. The output power curve can reflect that the output power remains constant when the temperature rises, and the change of the output power during the temperature maintenance period. Because it is DC heating, if the temperature of the rotor exceeds a certain value, a relatively large induced current will be generated in the coil winding of the rotor, which will lead to an undesirably long heating time and damage the winding material. Therefore, controlling the output power by a constant power supply can allow the rotor to be heated stably under ideal conditions.
[0043] At block 103, the error between the actual temperature and the target temperature is calculated to correct the output power of the constant power DC power supply. After the heating starts, there may be an error between the actual situation and the heating requirement, so a correction method can be set in this step to make the actual heating process more accurately meet the heating requirement by correcting the output power of the constant power DC power supply.
[0044] Different from adjusting current or voltage, controlling the output power of the power supply is a direct control method. It changes the on-site heating state of the rotor without taking into account the initial parameters of the rotor, environmental conditions, etc. This eliminates conversion and unnecessary control steps, provides timely feedback, and can improve production efficiency.
[0045] After the output power of the constant power DC power supply is adjusted, data can be collected again and calculated again. That is, blocks 102 to 103 can be repeated to determine whether the output power of the power supply needs to be corrected again. Thus, a closed-loop optimization process is formed, so that the actual heating condition of the rotor is close to the ideal condition.
[0046] You should know that in Figure 2 In the illustrated embodiment, unless otherwise specified or due to logical reasoning, the order of steps may be changed. For example but not limitation, data collection may be performed while power is supplied.
[0047] Figure 3 The method for manufacturing a motor involved in the present application is shown. Still taking the rotor as an example, at block 201, a rotor wound with coils is provided.
[0048] At block 202, the rotor core is heated and preheated by induction heating for a short period of time, such as 20 seconds.
[0049] At block 203, the coil windings of the rotor are heated. The heating is performed in the above-mentioned heating steps, the coil windings are connected to a constant power DC power supply and energized, and the heating time lasts for a short period of time, such as 30 seconds.
[0050] At block 204, the coil windings of the rotor are insulated. This step can be performed in a known manner, such as by placing the rotor in a varnishing machine and impregnating it with resin.
[0051] At block 205, the paint layer is cured. The rotor is placed in a warm chamber for drying and cooling, so that the paint layer is formed on the surface of the coil winding of the rotor. This step can be performed in a known manner.
[0052] You should know that in Figure 3In the illustrated embodiment, unless otherwise indicated or logically inferred, the order of steps may be changed. For example, but not limited to, the core may be heated in other ways, or the core and coil windings may be heated simultaneously, or a target heating curve may be set first, and then the core and coil windings may be heated.
[0053] Figures 1 to 3 The embodiments are also applicable to heating a stator of an electric machine and parts of a process for manufacturing a stator of an electric machine.
[0054] Figure 4 A schematic diagram of the application of the heating method involved in the present application in the field is shown. Still taking the rotor as an example. The figure shows only a part of the constant power DC power supply 300, including a first end 301 and a second end 302, and the first end 301 and the second end 302 can be a positive terminal and a negative terminal, respectively. The rotor 400 stands up and is located between the first end 301 and the second end 302. The rotor 400 can be positioned on the base 500 or fixed in other ways. When connected, the first end 301 and the second end 302 move closer to the rotor 400 and contact the rotor 400, thereby forming a power supply circuit between the rotor 400 and the constant power DC power supply 300.
[0055] The first end 301 and the second end 302 each have a power output end 311, 321 and a detection end 313, 323, such as a power output end with a larger contact area and a detection end with a relatively smaller contact area as shown in the figure. These ports remain in contact with the rotor 400 during the power supply process, thereby realizing power supply and detection. Among them, the detection ends 313, 323 are retractable ends, and in the illustrated embodiment, their length is greater than the power output ends 311, 321. When the power output ends 311, 321 are in contact with the parts to be heated, a power supply circuit is formed. When the detection ends 313, 323 are in contact with the parts to be heated, a detection circuit is formed. The detection ends 313, 323 are set to be longer, so that the power output ends 311, 321 can be in contact with the parts to be heated while the detection ends 313, 323 are retracted and remain in contact with the parts to be heated. A direct current passes through the rotor 400 between the two power output ends 311, 321. The detection terminals 313 and 323 monitor the circuit data of the rotor, and the circuit data value can be obtained through the detection terminals 313 and 323. The constant power DC power supply can also only have a power output terminal, and obtain the circuit data through a separately set detection circuit, such as connecting the detection instrument in series with the rotor to form a detection circuit.
[0056] In the illustrated embodiment, the constant power DC power supply 300 is connected to the commutator 404 of the rotor. The commutator 404 is connected to the coil winding 408, so the power output terminals 311 and 321 can be connected to the commutator 404 in a diagonal manner (also at intervals of 180° or in the diameter direction), which facilitates the circuit connection of the rotor 400. Of course, the power output terminal can be connected to the coil winding wound on the rotor body or to the coil winding on other parts of the rotor. If it is a stator, the power output terminal is directly connected to the coil winding.
[0057] The figure only shows a pair of first ends 301 and second ends 302 contacting the rotor, and there may be multiple pairs of first ends and second ends for batch heating of a larger number of rotors to improve efficiency.
[0058] Figure 5 A flow chart of the components of the heating motor involved in the present application is shown. Taking the rotor as an example, at block 601, the initial resistance and temperature of the rotor are recorded.
[0059] At block 602, a constant power DC power source is connected. Figure 4 In the manner shown, the rotor 400 is clamped between the first end 301 and the second end 302 of the constant power DC power supply 300. The power output terminals 311 and 321 of the first end 301 and the second end 302 are diagonally in contact with the commutator 404 of the rotor. The detection terminals 313 and 323 are in contact with the commutator 404 at the same time.
[0060] At block 603 , current and voltage are collected through detection terminals 313 , 323 to obtain the resistance value of the coil winding of the rotor, for example, calculated by the formula resistance=voltage / current.
[0061] At block 604, the actual temperature of the rotor is calculated based on the initial resistance and temperature, as well as the resistance value. In the case where the material does not change, the actual temperature is linearly related to the resistance value of the rotor. For example, but not limiting, given the initial resistance R0, the initial temperature T0, and the resistance value at a given time point is Rt, the actual temperature Tt at that time point can be obtained by the formula Rt=R0(1+α(Tt-T0)). Where α is the temperature coefficient of resistance. The actual temperature is obtained by calculation, and the data accuracy is improved. Of course, the actual temperature can also be obtained by instrument detection.
[0062] At block 605, a heating curve reflecting the target temperature and heating time of the rotor is established according to the defined target temperature and heating time of the rotor and the actual temperature of the rotor, see Figure 6 , Figure 6 The curve in shows the relationship between the target temperature and the heating time, where the horizontal axis is the heating time and the vertical axis is the temperature value corresponding to the heating time. Figure 6It can be seen that the target temperature gradually increases with the heating time.
[0063] At block 606, a curve of output power and heating time of a constant power DC power supply is derived based on the curve of target temperature and heating time. Figure 7 , Figure 7 The curve in shows the relationship between the output power of the power supply and the heating time, where the horizontal axis is the heating time and the vertical axis is the output power value of the power supply corresponding to the heating time. Figure 7 It can be seen that the output power of the constant power DC power supply is initially maintained at a constant output power value. After heating for a certain period of time, the temperature of the rotor reaches the required temperature. From this point on, the rotor needs to be maintained at this temperature to avoid excessive induced current in the coil winding. Therefore, the output power begins to decrease gradually until the required 3s heating time is over, and the output power decreases smoothly to zero. The reduction time of the output power is related to the maximum current provided by the constant power DC power supply and the maximum inductance generated by the coil winding during the heating process. For example but not limiting, in the illustrated embodiment, the maximum power supply current that the constant power DC power supply can provide to the rotor is 120A. The maximum power supply current that the constant power DC power supply can provide to the rotor is not less than 120A, the inductance of the coil winding is not more than 6.25mH, and the reduction time of the control output power value can be not less than 1.5s. For example, the maximum supply current is 120A, 130A, 150A, 180A, 200A or 250A, the inductance of the coil winding is 6.25mH, 6.75mH, 7.25mH, 7.75mH, 8.25mH, 8.75mH, 9.25mH or 10.25mH, and the reduction time of the output power value is controlled to be 1.5s, 2.0s, 2.5s, 3.5s, 4.5s, 6.5s, 7.5s, 8.5s or 10.5s. According to the inductance formula U=L*di / dt, when the maximum supply current is 120A, the inductance of the coil winding is 6.25mH, and the reduction time of the output power value is controlled to be 1.5s, accurate detection results can be obtained in real time. For example, the accuracy of the real-time voltage detection result is maintained within 0.5V in the heating stage and within 0.1V in the stable stage. In this case, according to the above formula, t=L*i / U=(6.25 / 1000)*120 / 0.5=1.5s is calculated, that is, the reduction time of the output power value is 1.5s.
[0064] You should know, Figure 6 and Figure 7 The target curve shown is only an example, and other target mathematical models may exist.
[0065] In the actual heating process, the actual heating situation may not completely conform to the target heating curve.
[0066] At block 607, the output power of the actual power source is compared with the output power of the target power source. The output power of the actual power source can be calculated based on the collected current and voltage data, and the actual temperature can be calculated from the collected current and voltage data as described above.
[0067] According to the comparison result, the power output of the constant power DC power supply is adjusted. If the actual output power is large, the power output of the power supply is reduced at box 608; if the actual output power is small, the power output of the power supply is increased at box 609. In addition, it is possible to return to box 604, collect current and voltage data again, and calculate the actual temperature of the rotor again. The actual output power is compared with the target output power again until the two are equal, and then the end is shown in box 610.
[0068] Although specific embodiments of the present application have been shown and described in detail to illustrate the principles of the present application, it should be understood that the present application can be implemented in other ways without departing from such principles.
Claims
1. A method for heating a coil component, wherein the coil component is a motor coil component used during motor manufacturing, characterized in that: connecting the coil winding of the coil component to a constant power DC power supply to provide a DC current to the coil winding, wherein during the power supply process, the output power of the constant power DC power supply is controlled to heat the coil component; and The output power of the constant power DC power supply is controlled so that the power value of the output power gradually decreases until the heating ends, wherein the time period for the output power to gradually decrease is not less than 1.5 s.
2. The method according to claim 1, characterized in that: An instruction is transmitted to the constant power DC power supply via a control interface provided on the constant power DC power supply to control the output power of the constant power DC power supply.
3. The method according to claim 1, characterized in that: The power output terminal and the detection terminal arranged on the constant power DC power supply are respectively contacted with the coil component, and the current and voltage are obtained through the detection terminal.
4. The method according to claim 3, characterized in that: The output power of the constant power DC power supply is corrected based on the acquired current and voltage.
5. The method according to claim 1 is characterized in that: The maximum current provided by the constant power DC power supply to the coil winding is not less than 120A, and the inductance generated by the coil winding is not greater than 6.25mH.
6. The method according to any one of claims 1 to 5, characterized in that: When the coil component is a rotor, the constant power DC power supply is connected to the coil winding via the commutator of the rotor in a diagonal manner; when the coil component is a stator, the constant power DC power supply is directly connected to the coil winding of the stator.
7. A system for heating a coil component, the coil component being a motor coil component used during motor manufacturing, characterized in that include: a constant power DC power supply, the constant power DC power supply being configured to be connected to the coil winding of the coil component to be heated so as to provide a DC current to the coil winding; as well as A controller is configured to be connected to the constant power DC power supply to control the output power of the constant power DC power supply so as to heat the coil component, and to control the output power of the constant power DC power supply so that the power value of the output power gradually decreases until the heating ends, wherein the time period for the output power to gradually decrease is not less than 1.5s.
8. The system according to claim 7, characterized in that: The constant power DC power supply has a control interface, and the controller is connected to the constant power DC power supply via the control interface to transmit instructions to the constant power DC power supply to control the output power of the constant power DC power supply.
9. A method for manufacturing a motor, characterized in that The following steps are involved: Providing a component wound with a coil; Heating the component by the method according to any one of claims 1 to 6; and The coils of the components are insulated.