Energy Conservation and Management by using Soft Start

The process of conserving or saving or preserving and preventing wastage of something (historical or natural or any quantity and etc.) can be termed as conservation. In our day-to-day life, we utilize various types of energy sources which can be classified as renewable energy resources and non-energy resources. The massive use of non-renewable energy may lead to several hazardous circumstances, such as air-pollution, water-pollution, land-pollution, global warming, and so on. There are various energy conservation tips to avoid this type of hazardous problems. Similarly, electrical energy can be conserved by various energy conservation techniques. In this article, let us discuss energy conservation and management by using a soft start technique.

Energy Conservation by Soft Start

There are various energy conservation tips and energy management solutions that include the soft start of single-phase pump motor, IGBT based soft start for induction motor, the soft start of induction motor by ACPWM, and electronic soft start for 3 phase induction motor. Let us discuss all the energy conservation tips and energy management solutions as follows:

Soft Start of Single Phase Pump Motor

The main intention of this project is energy conservation by a soft start. During the starting of the single phase pump motor more current is drawn compared to its rated value. This over current drawn during starting condition may lead to the damage of motor windings and energy wastage.

Thus, this problem of energy wastage and motor winding damage can be avoided using energy conservation by soft start technique. The project block diagram is shown in the figure below which consists of various blocks such as bridge rectifier, transformer, mains supply, back to back SCR, Opto-isolation, voltage regulator, soft start, and lamp (as load used instead of the motor for demonstration purpose).

To perform the soft-start operation of the motor, the voltage applied to the motor is gradually increased from low to high. This can be achieved using two anti-parallel SCRs connected in series with motor to supply. The operational amplifier provides delayed pulses to trigger SCRs, these delayed pulses are generated by comparing varying voltage & sawtooth voltage.

Energy Conservation by Soft Start of Induction Motor using IGBT

The main intention of this project to conserve energy by achieving a soft start control technique for an induction motor using IGBT.

This project is designed to avoid the usage of conventional Triac phase angle control drives. This project circuit provides (required) variable AC voltage at the starting condition of single-phase AC induction motor. The input voltage applied during a start can be varied from zero to maximum in short time as similar to triac control method.

In fact, this project uses pulse width modulation or PWM technique and produces very lower high order harmonics compared to triac based phase angle control technique. In this project, the AC voltage is directly modulated instead of using conventional converter topology. Hence, it is more economical and can be used for all low/medium power applications. The block diagram is shown in the above figure which consists of various blocks such as a power supply block, IGBT, zero-crossing detector, microcontroller, Opto-isolator, and so on. Thus, the project can be used for the conservation of energy by the soft start of the induction motor.

Electronic Soft Start for 3 Phase Induction Motor

The 3 phase induction motor project is designed for energy conversation by the soft start of an induction motor. Similar to single-phase induction motor, a three-phase induction motor also draws more current (higher than its capacity) during starting condition and causes the motor to reach full speed instantly.

Due to this, motor mechanical jerk and high electrical stress on the windings of the motor or windings may get burnt and causes more energy consumption. So, it is required to follow or innovate energy management techniques for achieving soft start of the motor, to reduce power consumption and safeguard the motor winding from damages.

The block diagram of the three-phase induction motor is shown in the above figure which consists of multiple blocks such as a power supply circuit, back to back SCR, lamps are used as a load instead of induction motor for demonstration purpose, control unit. Here, in this project, primarily during the starting condition of three-phase motor the SCRs are triggered by heavily delayed firing angle.

Thus, during starting condition, low voltage is applied to the motor and then progressively delay is reduced until it reaches zero voltage triggering. Hence, energy conservation by soft start of 3 phase induction motor is achieved and motor is made to pick up full speed gradually.

Do you know want to design electronics projects based on energy conservation and management techniques by using soft start? Then, please share your queries, views, ideas, suggestions, and comments by posting in the comments section below.