Electric motor is a type of machine which converts electrical energy into mechanical energy using the interaction between magnetic field and current in its winding to produce/generate force in the motor. If we actually reverse this process then mechanical energy is converted into electrical energy and that is done by generators . Electromagnetism is the main phenomenon that is used by motors. Show Basic Parts of the Motor:Coming to the parts of motors, major parts of motor are as follows Rotor: Stator: Air Gap: Commutator: So there are multiple types of motors with their own importance. Types of Motors and their Importance:As you have seen now that there are many types of motors and we talk about our industries around 70% energy is used by these motors and a huge proportion this energy is wasted. By reducing this wastage, companies not only help the environment, but also cut their costs and improve profitability.
What is Motor Efficiency:The ratio between motor Output and Input is called efficiency which is indicated by the symbol of “η” and represented in the “%”. or This is the factor which tells about performance of the motor. It is the ratio between output and input power at shaft it can be written as efficiency (e) = output power / input power i.e. Motor Efficiency = Motor Eff = Motor Out Put Power / Motor Input Power Motor efficiency is denoted by the symbol of eta= η. Efficiency = η = (Output / Input) x 100 Or Efficiency = η = Input – Losses / Input Or Efficiency = η = Output / Output + Losses. There is no such a machine without losses. thus, the value of output of a machine is always less than the input. i.e. Output = Input – Losses In other words; Input = Output + Losses Therefore, we can write the efficiency formula as well. Efficiency = η = Input – Losses / Input Or Efficiency = η = Output / Output + Losses. Power Stages in DC Motors and their Efficiencies.Losses occur during conversion of electrical energy into mechanical energy in electrical motor. These losses and conversion of energy in the motor is known as the power stages of a DC motor which is shown in the below diagram. Explanation of Power stages and Different Efficiencies in the motor Now, Input power minus copper losses is equal to the driving power (EbIa in Watts) which is produced in the motor armature (also known as Developed Power). The remaining power is not the overall output power because, there are also iron and friction losses occur in DC Motor which is 10 – 20% of the total losses. At last, the driving power minus iron and friction losses is equal to the overall output power (mechanical power) at motor shaft. Mathematically; Copper losses = A – B Iron and Friction losses = B – C Overall or Commercial efficiency = ηc = C/A = Types of Motor EfficienciesMechanical Efficiency = ηm = C/B = Electrical Efficacy = ηe = B/A = Overall or Commercial efficiency = ηc = C/A = The above story is shown in the below fig. What is Motor Efficiency & How to improve it
How to improve the Motor Efficiency?This efficiency of motor is affected by few losses which include resistance losses, mechanical losses due to friction, losses due to dissipation of magnetic energy in core and different losses depending upon type of material used. In order to make a motor more efficient we have to reduce losses in the motor. Here are some methods or tips that can be adopted to improve the factor of efficiency in motors.
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First step will be to continuously monitor and document that which motors are present under your supervision, how old are they, the horsepower they are providing and ratings, ,what is the controls level present in your facility and to identify the loads. Use some kind of efficiency calculator like motor master. There are three important aspects that must be checked which are Voltage unbalance, and Power factor. Voltage and current unbalance is caused by difference in values in three phase system respectively. While Power factor (PF) is normally originated due to motors and other heavy accessories like transformers.. PF is actually percentage or a number, with 100%, or 1 when it is ideal. Power factor is the ratio of real (working) power (kW) to apparent (total) power that is in KVA and it is a combination of real power and reactive power (kilovars kVAR). Bad power factor can cause increase in electric utility bills so it must e controlled. If any problem occurs with any of these variables, correcting those problems must be immediately removed, using software to estimate efficiency of a motor can be useful. By concluding the articles it must be known that these all factors explained must be kept in mind while selecting a motor and making it operational. Moreover to increase the life span of the motor inspection on regular intervals must be carried out. Related Posts: |