Three-phase asynchronous motors are machines extremely robust electric motors, which require very little maintenance and are frequently ent used in the industrial sector. We re them find in a wide variety of applications such as fans, pumps, complex machinery modular, machines requiring torque and has precision at very low speeds as well as a dynamic ic high and also for machines with high power meeting. Thanks to the evolution of power electronics and due to the lower cost of asynch engines rounds, number of applications, which yesterday used words direct current or synchro motors one is, today use an asynchronous motor associated to a variable speed drive. Depending on the processes driven, asynchronous motors s need a stable power supply provided by a UPS: a sudden interruption of the power supply electricity could indeed cause damage are materials and affect the quality of the product. Asynchronous motors are usually powered ed at the stator, and the current is induced in it ns it rotor. It is for this reason that we speak equal mention of "induction motors or machines". The asynchronous machine is mainly used e n motor, but it is sometimes used in general rice. Coupling and speed regulation problems and voltage of synchronous machines do not exist ace in the case of asynchronous machines. The generatri these asynchronous therefore make it possible to produce electricity in small infrastructures, without s require supervisory staff. other ut ilization, the braking, by absorbing energy when the machine is not connected to a constant frequency network (e.g.: absorption of the energy of a load descends ante). Regenerative braking with speed variation speed assumes power to the frequency machine in this variable; in other words, the use of variator rs. In the same way, thanks to the power electronics session, induction motors are increasingly used és as generators. This is for example the case of wind turbines. The purpose of this document is to provide a non-e xhaustive of problems that may occur when sizing the UPS for the power supply n induction motors, with or without drives of speed. This document does not make it possible to design the in installation nor to select a UPS.
Motors not associated with a drive Asynchronous machines are nowadays very common widely used as motors, in a range of power ranging from a few Watts to several c hundreds of kW. For power applications At- beyond a few kW, asynchronous motors are u powered only by current networks three-phase AC. Due to the sensitivity of the process or the c certain applications, the network can be backed up by an UPS. During start-up, the inrush currents can att reach rms current values comprised in be 4 and 7 times the nominal value, while the torque is on average 1.5 to 2.4 times the value of the hit THE nominal. The starting time depends on the inertia moving mass, rotational speed torque and engine acceleration torque. The Vs Peak current values are even higher, and you can reach 10 times the value of the rms current nominal effect. The high inrush currents, combined with the impedance of line, lead to a drop in the voltage at the calf of the distribution line, in particular for the s loads located close to the motor.
There are several ways to limit the current startup s, the most common being: The start Y/ ∆ ; An autotransformer; A soft starter: The rotor rheostat is also a solution approx. suitable for some very specific applications ues. The choice must be made according to a compromise between the type of application and the costs involved
Three-phase asynchronous motors are machines extremely robust electric motors, which require very little maintenance and are frequently ent used in the industrial sector. We re them find in a wide variety of applications such as fans, pumps, complex machinery modular, machines requiring torque and has precision at very low speeds as well as a dynamic ic high and also for machines with high power meeting. Thanks to the evolution of power electronics and due to the lower cost of asynch engines rounds, number of applications, which yesterday used words direct current or synchro motors one is, today use an asynchronous motor associated to a variable speed drive. Depending on the processes driven, asynchronous motors s need a stable power supply provided by a UPS: a sudden interruption of the power supply electricity could indeed cause damage are materials and affect the quality of the product. Asynchronous motors are usually powered ed at the stator, and the current is induced in it ns it rotor. It is for this reason that we speak equal mention of "induction motors or machines". The asynchronous machine is mainly used e n motor, but it is sometimes used in general rice. Coupling and speed regulation problems and voltage of synchronous machines do not exist ace in the case of asynchronous machines. The generatri these asynchronous therefore make it possible to produce electricity in small infrastructures, without s require supervisory staff. other ut ilization, the braking, by absorbing energy when the machine is not connected to a constant frequency network (e.g.: absorption of the energy of a load descends ante). Regenerative braking with speed variation speed assumes power to the frequency machine in this variable; in other words, the use of variator rs. In the same way, thanks to the power electronics session, induction motors are increasingly used és as generators. This is for example the case of wind turbines. The purpose of this document is to provide a non-e xhaustive of problems that may occur when sizing the UPS for the power supply n induction motors, with or without drives of speed. This document does not make it possible to design the in installation nor to select a UPS.
Motors not associated with a drive Asynchronous machines are nowadays very common widely used as motors, in a range of power ranging from a few Watts to several c hundreds of kW. For power applications At- beyond a few kW, asynchronous motors are u powered only by current networks three-phase AC. Due to the sensitivity of the process or the c certain applications, the network can be backed up by an UPS. During start-up, the inrush currents can att reach rms current values comprised in be 4 and 7 times the nominal value, while the torque is on average 1.5 to 2.4 times the value of the hit THE nominal. The starting time depends on the inertia moving mass, rotational speed torque and engine acceleration torque. The Vs Peak current values are even higher, and you can reach 10 times the value of the rms current nominal effect. The high inrush currents, combined with the impedance of line, lead to a drop in the voltage at the calf of the distribution line, in particular for the s loads located close to the motor.
There are several ways to limit the current startup s, the most common being: The start Y/ ∆ ; An autotransformer; A soft starter: The rotor rheostat is also a solution approx. suitable for some very specific applications ues. The choice must be made according to a compromise between the type of application and the costs involved
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