Electrical Drives: Parts, Advantages, Disadvantages and Application
Table of Contents
Electrical drives are the types of systems that are used to regulate the motion of electrical machines. In other words, electrical drive refers to a drive that makes use of an electric motor. Any primary source of energy can be used by the electrical drive, including diesel or gasoline engines, gas or steam turbines, steam engines, hydraulic motors, and electrical motors. The mechanical energy required by the drive for motion control is provided by this prime mover.
The figure below displays the electrical drive’s block diagram. The electrical motor is a component of electrical loads like fans, pumps, trains, etc. Regarding speed and torque, an electrical load’s requirements are established. For the load drive, the motor that best matched the load’s capabilities is selected.
Parts of Electrical Drives
The power modulator, the motor, the controlling unit, and the sensing units are the essential components of electrical drives. Below is a detailed explanation of each component.
Power Modulator
The source’s output power is controlled by the power modulator. It regulates the power flowing from the source to the motor in order for the motor to transmit the speed-torque characteristics needed by the load. Excessive current is drawn from the source during transient operations like starting, stopping, and speed reversing. This excessive current draw could overload the source or result in a voltage drop. The power modulator limits the source and motor current as a result. When an induction motor is used and the energy source is DC, the power modulator converts the energy into AC in order to meet the needs of the motor. Additionally, it decides whether the motor will be motoring or braking.
Control Unit
The power modulator, which operates at low voltage and power levels, is controlled by the control unit. The power modulator is also controlled by the control unit as needed. Additionally, it generates the instructions for the motor’s and power modulator’s protection. a command signal from an input to the control unit that modifies the drive’s operating point.
Sensing Unit
It detects specific drive parameters like motor speed and current. It was primarily necessary for closed loop operation or protection.
Advantages of Electrical Drives
The following are the advantages of electrical drive.
- Their working is independent of the environmental condition.
- The electric drive has very large range of torque, speed and power.
- The electric drives operate on all the quadrants of speed torque plane.
- The electric drives are free from pollution.
- The efficiency of the drives is high because fewer losses occur on it.
- The drive can easily be started and it does not require any refuelling.
Numerous benefits of electric drives are listed above. The drive’s lone drawback is that occasionally the mechanical energy generated by the prime mover is converted first into electrical energy, which is then transformed into mechanical work with the aid of the motor. This is possible with the aid of the electrical connection between the load and the prime mover. The mechanical energy that is already present from a non-electrical prime mover is occasionally first transformed into electrical energy by a generator and then back into a mechanical energy of an electrical motor due to the following advantages. The load impact on the drive’s flexible control characteristic is thus connected electrically to the prime mover’s non-electrical operation.
Example –The diesel engine assists the diesel locomotive in producing the diesel energy. With the aid of the generator, mechanical energy is transformed into electrical energy. So The other locomotive is driven using this electrical power.
Disadvantages of Electrical Drives
The power failure completely disabled the whole of the system.
- It can cause noise pollution.
- The drive’s use is restricted because it cannot be used in locations without a power supply.
- It has a poor dynamic response.
- The initial cost of the system is high.
- The system may be damaged during conductor failure or a short circuit, which leads to a number of issues.
- The output power obtained from the drive is low.
Application of Electrical Drives
So It is utilized in a wide range of domestic and industrial applications, including washing machines, fans, pumps, rolling mills, paper machines, textile mills, machine tools, and transportation systems.