Project

Single Sided Matrix Converter fed Brushless DC Motor for Energy Conservation

Objective: 

A three-phase BLDC motor driven by a single sided matrix converter (SSMC) with hysteresis band control has been opted for its high reliability, fault tolerance, and compact structure. A new technique is contrived and proposed to drive the BLDC motor fed by matrix converter to accomplish desired speed-torque characteristics meeting the load requirements. The use of Single Sided Matrix converter with BLDC motor is used to achieve operation without any complex control circuitry.

Origin of proposal idea: 

In safety critical applications, the fault tolerance and reliability of the whole electrical drive including the motor and power converter are equally of great importance. From the power converter perspective, a single sided matrix converter (SSMC) is highlighted to attain desired torque-speed characteristics, high reliability owing to the absence of bulky capacitors, and hence such configuration can be made to reliably operate in the extremes of aerospace environmental conditions and simple commutation technique. 

Deliverables 

The BLDC motor has the potential to provide the highest power density when compared to its other counterparts. The square-wave current supply effectively utilizes most of the back-electromotive-force (EMF) harmonics to produce useful power output. The BLDC motor has the advantage of simpler control than the PMSM and less onerous sensing requirements. No complex DSP programming is required, which, to some degree, improves the reliability. Therefore, BLDC drives are strong/desired candidates for aerospace applications. 

The BLDC motors are either driven by indirect AC-AC converters or by direct AC-AC converters. Direct AC-AC converters i.e. matrix converters are going to be utilized in this research work to drive the three phase BLDC motor and it eliminates the bulky DC link energy-storage element to its merit. A matrix converter converts the constant voltage and constant frequency supply to AC voltage of variable magnitude and variable frequency to accomplish desired torque-speed characteristics of BLDC motor in meeting the load requirements. To achieve this, an effective control technique is essential to be contrived to generate the switching pulses. 

To attain, desirable torque-speed characteristics, it is essential to control the torque and speed of the machine. For accomplishing this, i.e (1) to control the speed of the BLDC motor, a unique hybrid control is devised that utilizes the merits of Proportional Integral (PI) controller and Fuzzy Logic Controller (FLC), (2) in accession to control the torque in tandem with speed variable, hysteresis current controller is also taken into consideration for attaining desired results.

Details of approach intended to be adopted in the execution of the Project:

1. A three phase BLDC motor driven by a single sided matrix converter (SSMC) with hysteresis band control has been opted.
2. The use of an SSMC with a BLDC motor is novel and is used to achieve operation without a microprocessor. 
3. A simple hysteresis current control strategy is implemented to control motor torque.
4. The multiphase SSMC provides high reliability and fault tolerance with the penalty of more power devices. This approach is highly suitable for pumps, compressors and propulsion applications.

Amount: Rs. 23.252 Lakhs