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The electric motor has put forward rigorous requirements and brought new problems

The frequency conversion motor adopts the 'dedicated frequency conversion induction motor + frequency converter' AC speed regulation method, which greatly increases the degree of mechanical automation and production efficiency, and increases the equipment miniaturization and comfort. It is currently replacing the traditional mechanical speed regulation and DC speed regulation schemes. Class B temperature rise design, class F insulation manufacturing. Using polymer insulation material and vacuum pressure dip paint manufacturing process and special insulation structure, the High-end waterproof motor factory electrical windings are greatly improved in insulation withstand voltage and mechanical strength, which is sufficient for motors. High-speed operation and resistance to high-frequency current shock of inverter and damage to insulation by voltage. High balance quality, high vibration level of R-level (reduced vibration level) mechanical parts, high precision machining, and the use of special high-precision imported bearings for high-speed operation. Forced ventilation and cooling system, all adopt imported axial flow fan ultra-quiet, high life, strong wind.

Ensure that the motor can be effectively cooled at any speed, can achieve high-speed or low-speed long-term operation. YP series motors designed by AMCAD software, and traditional Compared with variable frequency motors, it has a wider speed range and higher design quality. The special magnetic field design further suppresses the high-order harmonic magnetic field to meet the design indicators of broadband, energy saving and low noise. It has a wide range of constant torque and power speed regulation characteristics, smooth speed regulation, and no torque ripple. The inverters have good parameter matching, and with vector control, it can achieve zero speed full torque, low frequency large torque and high precision speed control, position control and fast dynamic response control. YP series special frequency conversion motors can be equipped with brakes and encoders Delivery, in this way, you can obtain precise stop, and achieve high-precision speed control through closed-loop speed control. Use 'reducer + frequency conversion dedicated motor + encoder + inverter' to achieve ultra-low speed stepless speed precise control. YP series inverter special-purpose motors have good versatility, and their installation dimensions comply with IEC standards and are interchangeable with general standard motors. The speed regulation and control of electric motors is one of the basic technologies for various types of industrial and agricultural machinery and electrical appliances for office and people's livelihood. With the amazing development of power electronics technology and microelectronic technology, the use of 'dedicated variable frequency induction motor  frequency converter' AC speed regulation method is leading a replacement in the field of speed regulation with its excellent performance and economy. Renewal of the traditional speed regulation method.

The gospel it brings to all walks of life lies in: greatly improving the degree of mechanical automation and production efficiency, saving energy, improving product qualification rate and product quality, correspondingly increasing the power system capacity, equipment Miniaturization and increased comfort are replacing traditional mechanical speed regulation and DC speed regulation solutions with fast speeds. Due to the special nature of variable frequency power supplies, and the system's requirements for high-speed or low-speed operation and dynamic speed response, it is the main body of power The electric motor has put forward rigorous requirements and brought new problems in the aspects of electromagnetic, structure and insulation to the electric motor.

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the rotor of the tested motor repeats the above test

The measurement of the moment of inertia of the variable frequency motor includes the suspended rotor swing method, the no-load deceleration method, and the auxiliary pendulum method. This article introduces the test content of the three kinds of method of the moment of inertia of the variable frequency motor according to the relevant motor test standards. Moment of inertia is a measure of the inertia (the characteristic of a rotating object maintaining its uniform circular motion or stationary) when it rotates around an axis. It is one of the indicators to measure the responsiveness and flexibility of a motor. Its magnitude depends on the shape of the object, its mass distribution, and the position of the shaft.

It can be said that the inertia of an object with respect to rotary motion. The role of rotational inertia in rotational dynamics is equivalent to the mass in linear dynamics, describing the relationship between angular momentum, angular velocity, moment and angular acceleration. I. Measurement of the moment of inertia of the suspension rotor swing method 1. Measurement of the moment of inertia of the single wire method Measurement of the moment of inertia of the motor rotor using the single wire torsional swing comparison method. Choose a metal Blower motor with a uniform density to make a fake rotor. The shape of the fake rotor should be a simple cylinder, so that the moment of inertia of the fake rotor can be calculated more accurately using formula (1). The quality of the dummy rotor should be able to straighten the selected wire without deforming the wire. The dummy rotor is hung reliably on one end of a wire with a length of l \u0026 ge; 0.5m, and the other end of the wire is fixed on the support. The axis of the wire should be concentric with the axis of the dummy rotor and perpendicular to the ground.

Twist the dummy rotor around the mandrel at an appropriate angle, carefully measure the number of reciprocating swings N and the required time t (s), and obtain the average swing period T \u0026 rsquo; (T \u0026 rsquo; = N / t). Under the same conditions, the rotor of the tested motor repeats the above test, and the average value T of its swing period is obtained according to the above method, and the moment of inertia J of the tested motor is calculated according to formula (2). The moment of inertia of the pseudo-rotor J \u0026 rsquo; (kg * ㎡) is calculated by formula (1):-(1) where: m--the mass of the cylinder with a diameter of D, the unit is kilogram (kg); Diameter in meters (m). The moment of inertia J (kg * ㎡) of the rotor of the tested motor is calculated according to formula (2):-(2) where: T--average of the swing period of the tested motor rotor, in seconds (s); T \u0026 rsquo; -The average value of the period of the wobble of the pseudo-rotor in seconds (s). 2. Measuring the moment of inertia by the double wire method Use two parallel wires to suspend the rotor of the motor under test so that the center line of the shaft is perpendicular to the ground. Twist the rotor so that it swings about the axis. The twist angle from the centerline of the shaft should not be greater than 10 \u0026 deg ;. Carefully measure the time required for several swings to find the average value T of the swing period.

The moment of inertia J (kg * ㎡) is calculated according to formula (3):-(3) where: --l--the length of the wire, the unit is meter (m); m--the mass of the rotor of the tested motor, the unit is Kilogram (kg); g--gravitational acceleration in meters per second squared (m / 2 ^ s); a--distance between two steel wires in meters (m). 2.Measure the moment of inertia by the no-load deceleration method. This method is used to measure the moment of inertia of the machine when the power is above 100kW. During the test, the VEMT speed reducer increased the speed of the motor under test and exceeded the synchronous speed. Then, the power was cut off or the drive mechanism was disconnected, and the speed change n (r / nin) was measured within the range of 1.1 to 0.9 times the synchronous speed. The required time t (s). Moment of inertia J (kg * ㎡) is calculated according to formula (4):-(4) 3. Auxiliary pendulum method to measure the moment of inertia This method is used to measure the moment of inertia of a motor with a rolling bearing. Auxiliary pendulum of known mass shall be fixed to the center of the end face of the shaft of the motor under test with an arm with the smallest mass possible. The pendulum arm shall be at right angles to the axis. When the shaft is equipped with a pulley or a half coupling, they can also be used to fix the pendulum. During the test, the deviation between the initial position and the rest position of the pendulum should not be greater than 15 °. After the start of the swing, measure the time required for 2 to 3 swings to find the average of the swing period. The moment when the pendulum passes through the rest position is used as the starting point for measuring the swing period. The moment of inertia J (kg * ㎡) is calculated according to formula (5):-(5) where: m--the mass of the auxiliary pendulum, in kilograms (kg); r--the center of gravity of the auxiliary pendulum to the center of the shaft The distance of the line, in meters (m); T-average value of the swing period of the auxiliary pendulum, in seconds (s). For motors with a power of 10kw ~ 1000kW, when the auxiliary pendulum is selected, the swing period should be 3s ~ 8s. In order to check, it is recommended to repeat the measurement with slightly different pendulum mass.

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The main reasons for inaccurate positioning include

Because the open-loop control system has the advantages of convenient operation and low price, the open-loop control reaction stepper motor is adopted in our country. Although stepper motors are widely used, they cannot be used under ordinary conditions like ordinary AC (direct current) motors, and the running speed from the beginning to the end is theoretical. When the limit starting frequency of the motor is greater than the speed , The motor can run as required, and can reach the expected operating speed. When running to the end of the stroke, it can also immediately announce the pulse that can complete the stop function and stop the motor.

However, the actual situation is that the limit starting pre-rate that can be completed by a stepper motor is low, which is far from meeting the requirements of higher running speed. Under such operating conditions, if the motor is forced to start directly at the required speed (greater than the limit start rate), 'lost steps' or no response will occur. When the motor runs to the end, although the pulse has been suspended immediately , Stop it, but because of the inertia effect, the phenomenon of overshooting will occur, that is, overshooting occurs.

It is particularly noteworthy that, in order to ensure the positioning accuracy of the system (the motor's lifting speed is slow to avoid 'out of step') Or 'overshoot' to achieve high positioning speed, the mainstream system will divide the positioning process into coarse positioning stage and fine positioning stage. According to production practice experience, 'lost steps' and 'overshoot' are The two most commonly presented stepper motors in operation are the 'culprits' that seriously affect the positioning accuracy of stepper motors. The main reasons for inaccurate positioning include: (1) The initial starting speed is required to be too high, exceeding the limit starting frequency of the motor, Range hood motor factory or the acceleration is too high, causing 'lost steps;' (2) The power of the motor does not meet the system requirements; ( 3) The actuator operation suffered a lot of disturbances; (4) the controller of the control system malfunctioned; (5) the pulse was lost during the commutation, the positioning in one direction was accurate, and the positioning after the commutation showed errors, although the number of commutation times The more significant the product of its error is added; (6) the software has planning shortcomings; (7) where the timing belt is used, the software compensates too much or too little.

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Motors have put forward strict requirements and brought new problems in the fields

The frequency conversion motor adopts the 'special frequency conversion induction motor + frequency converter' communication speed regulation method, which greatly improves the degree of mechanical automation and production efficiency. The equipment is miniaturized and adds comfort. It is currently replacing the traditional mechanical speed regulation and DC speed regulation plans. Class B temperature rise plan, class F insulation production. The use of polymer insulation materials and vacuum pressure dip paint production technology and the use of special insulation structures make electrical windings have a great improvement in insulation withstand voltage and mechanical strength, which is enough to serve as a motor. High-speed operation and resistance to high-frequency current shocks and voltage damage to insulation. High balance quality, high vibration level of R-level (reduced vibration level) mechanical parts, high precision machining, and the use of special high-precision imported bearings, which can work at high speed. Forced ventilation and heat dissipation system, all use imported axial flow fans with ultra-quiet, high life and strong wind. 

Ensure that the motor can be effectively cooled at any speed, and can complete high-speed or low-speed long-term operation. YP series motors planned by AMCAD software, and traditional Compared with variable frequency motors, it has a wider speed regulation scale and higher planning. After the special magnetic field planning, the higher harmonic magnetic field is further satisfied to meet the planning indicators of broadband, energy saving and low noise. It has wide-scale constant torque and power speed regulation characteristics, stable speed regulation, and no torque ripple. All types of frequency converters have outstanding parameter matching. Together with vector control, it can complete zero speed full torque, low frequency large torque and high precision speed control, position control and fast dynamic response control. YP series frequency conversion special motors can manufacture brakes. The encoder is supplied, so that accurate parking can be obtained, and high-precision speed control can be achieved through closed-loop speed control. Select 'reducer + frequency conversion dedicated motor + encoder + inverter' to complete ultra-low speed stepless speed precise control . 

YP series inverter special-purpose motors have good versatility, and their device dimensions comply with IEC specifications, and are interchangeable with general-standard motors. The speed regulation and control of electric motors is one of the basic skills of various industrial and agricultural machinery and office and electrical appliances for people's livelihood. With the amazing development of power electronics skills and microelectronics skills, the communication speed regulation method of 'dedicated frequency conversion induction motor + frequency converter' is being used to guide an alternative tradition in the field of speed regulation with its excellent performance and economy. The updating and updating of the speed regulation method. The gospel it brings to all walks of life lies in: greatly improving the degree of mechanical automation and production efficiency, saving energy, improving the product qualification rate and product quality, correspondingly improving the power system capacity, and small equipment It is replacing the traditional mechanical speed regulation and DC speed regulation plan with a fast speed. Because of the special nature of the variable frequency power supply, and the system's requirements for high-speed or low-speed work, dynamic response to the speed, Range hood motor manufacturers etc., Motors have put forward strict requirements and brought new problems in the fields of electromagnetics, structure and insulation to motors.

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The factors that can affect the safety of the stepper motor in the process of use

We all know that no matter whether it is a stepper motor or any kind of mechanical equipment, even if it is designed and manufactured with precision, its safety in practical use is not 100% guaranteed, and it will exist in long-term use. Certain security risks are mainly due to the fact that it is subject to various factors such as man-made and natural factors in its use, which leads to the problem of potential security risks. The following gives us a detailed explanation of the safety of stepper motors affected by these factors.

Improper use by users. In fact, in the process of using a stepper motor, the biggest factor that can affect the safety of its equipment use is that in the actual operation, the user responsible for the operation did not use the correct method to operate, so that the equipment There are some hidden safety hazards in the application process.运用 Excessive use. The factors that can affect the safety of the stepper motor in the process of use. In addition to the user's improper use methods mentioned above, in the Range hood motor process of practical use, if the user is overloaded, then its Security is not guaranteed.

It can be seen that if the stepper motor wants to ensure its own safety in operation, it must pay attention to the above-mentioned influential factors in the process of its practical use. The above is the introduction of the safety of stepper motors affected by these factors. If stepper motors want to gain more long-term development space in the current market development, then it must be continuous in its development. Improving the security of its application, only in this way can it attract the attention of users and achieve the desired development results.