Automation of the stone materials dosing process, controlled by variable frequency drives

<p>The objective of this article is to determine to what extent the automation of the stone materials dosing process, controlled by sequential drive of frequency variators, contributes to improving the productivity of a company dedicated to the production of asphalt in Peru for which, initially, the characteristics of the procedure that will lead to achieving the automation will be described. The results will then be displayed with respect to the indicators used to compare productivity before and after automation. The automation will be done by means of the logo 230RE controller, which will be connected to three frequency inverters, the programming development will be through the logo soft comford V8 software, for the sequential actuation, timers with connection delay will be used. Applying the automation, it is possible to improve the annual efficiency by an average of 58.30%, this is reflected in the monthly decrease in production time by 13.92%, in turn increasing the amount of stone material produced by an average of 43.77%. Likewise, it is possible to significantly reduce the production loss capacity by an annual average of 93.99%.</p>

Condition Monitoring and Feature Extraction of Stator Current Phasors for Enhanced Fault Diagnosis in AC Drive

AC drives are employed mainly in process plants for various applications. In most industrial applications, Induction motor drives are preferred as they are robust, reliable, and efficient. Process industries have seen a paradigm shift from manual control to automatic control. Advancements in power electronics technology have led to smooth control of the induction motor using variable frequency drives over an entire speed range. Variable Frequency Drives (VFD) comprises of Voltage source inverter and a three phase squirrel cage induction motor. Various electric faults that are incipient in the VFD cause an abrupt change in circuit parameters resulting in insulation damage, reduced efficiency, and leading to catastrophic failure of the entire system. Hence, continuous monitoring of the system parameters such as stator current, speed, and the vibration of the machine is essential to diagnose incipient faults in the system. AI techniques have been effectively used in the fault diagnosis of electrical systems. In the proposed work, simulation results of machine learning-based fault diagnosis techniques are presented. Real-time IoT-based condition monitoring of the Variable Frequency Drive is also implemented for enhanced fault diagnosis of various incipient electrical faults in AC drives. The experimental results obtained are validated with the simulation data.

Thermal Design of Variable Frequency Drives for Hybrid and Electric Transport Applications

The Electrification of commercial vehicles is happening at a rapid pace. Most of the major automotive corporations are pursuing this opportunity to include electric vehicles in their portfolios. The commercial trucking industry has also been exploring the use of electric vehicles for goods transport including perishables. The transition to electrically driven vehicles has led to the need for electrically driven HVAC systems. To support this evolving commercial market, we developed an electrically driven variable speed compressor platform comprising of compressor and variable frequency drive (VFD). The product platform addresses two categories of vehicles: 1) Hybrid vehicle – the vehicle in this category uses conventional IC engine and has traditional batteries that output 48VDC. 2) Electric vehicle – the vehicle in this category is electrically driven using battery bank or traction drive that gives 650VDC as output. Hence, 650V DC is input to VFD. Both these applications were addressed with two drive designs. In this paper, we discuss the thermal design aspects of both 48V and 650V variable frequency drives. In this publication, the product development process is described from product conception, to final product. The mechanical / environmental design considerations while designing these drives were, (1) The drive was expected to be mounted under the vehicle bed and hence should be strong enough to withstand shock and vibration, (2) the drive was decided to be air cooled (4) the drive was designed to be IP67 so that it can withstand harsh road conditions, (5) the desired operating temperature range was between −40°C to 85°C for 48V and −40°C to 65°C for 650V and (6) the estimated time of service was expected to be 10 years. We were able to achieve an operating margin of −40°C to 70°C at full load for hybrid vehicle drive (48VDC) and −40°C to 65°C for electric vehicle drive (650VDC) using air cooling.

Application of Matrix VFD for Power Factor Improvement in LED Lighting Sources Loaded Power Distribution Lines

In this paper, a novel approach to matrix-converter-based variable frequency drives is presented. It is proposed that these drives are used to provide or draw out reactive power from the power distribution line, keeping the power factor close to unit and, simultaneously, performing their primary function of motor powering and speed control. This application of matrix-converter-based variable frequency drives is required due to the need to compensate for capacitive reactive power generated by light emitting diode lighting devices. In this study, the reactive power compensation range of the matrix-converter-based variable frequency drive is determined, and a method is proposed to extend the compensation range.

Instantaneous Electromagnetic Torque Components in Synchronous Motors Fed by Load-Commutated Inverters

This paper proposes time-domain analytical expressions of the instantaneous pulsating torque components in a synchronous machine air gap when supplied by a load-commutated-inverter (LCI) system. The LCI technology is one of the most used variable frequency drives when very high power and low speed are required in applications such as pipeline recompression and decompression, as well as liquefied natural gas compression. In such applications, synchronous motors are used because of their high efficiency resulting from a separated supply of the current to their rotor through the excitation circuit. These applications usually have long and flexible shafts, which are very sensitive to torsional vibration excitation when their natural frequencies interact with any external torque applied to the shaft. A torsional analysis is required by international standards to assess the survivability of the shaft through the overall speed range of the motor. Therefore, the magnitude and frequencies of the motor air-gap torque are needed for such evaluation. The proposed developments are supported by numerical simulations of LCI systems in a large range of operation range. From the simulation results, torque harmonic families are derived and expressed in a parametric form, which confirm the accuracy of the proposed relationships.

Analysis of natural gas consumption and energy saving measures for small and medium-sized industries in the greater Toronto area

A total of 15 energy (natural gas) audits were conducted for industrial sites from food processing, packaged goods and finishing processes (powder coating) sector. Natural gas consumptions, performances of major gas consuming equipment and savings from proposed energy measures were analyzed for the audited sites. Proposed energy saving measures included reduction in non-productive consumption, tune-up of gas-fired equipment, optimization of boiler loads, heat recovery through feedwater economizer and reduction in oven exhaust using variable frequency drives (VFDs). Gas savings achieved by employing VFDs showed great potential ranging from 13% to 49% of oven consumptions while savings for feedwater economizer ranged from 3.4% to 18.4% of boiler consumptions. Other measures mentioned above, though relatively simpler to implement, also showed potential of considerable savings. Associated fuel cost savings and the reduction in greenhouse gas emissions were also estimated. Furthermore, a MATLAB program was created to calculate boiler efficiencies.

Analysis of natural gas consumption and energy saving measures for small and medium-sized industries in the greater Toronto area

A total of 15 energy (natural gas) audits were conducted for industrial sites from food processing, packaged goods and finishing processes (powder coating) sector. Natural gas consumptions, performances of major gas consuming equipment and savings from proposed energy measures were analyzed for the audited sites. Proposed energy saving measures included reduction in non-productive consumption, tune-up of gas-fired equipment, optimization of boiler loads, heat recovery through feedwater economizer and reduction in oven exhaust using variable frequency drives (VFDs). Gas savings achieved by employing VFDs showed great potential ranging from 13% to 49% of oven consumptions while savings for feedwater economizer ranged from 3.4% to 18.4% of boiler consumptions. Other measures mentioned above, though relatively simpler to implement, also showed potential of considerable savings. Associated fuel cost savings and the reduction in greenhouse gas emissions were also estimated. Furthermore, a MATLAB program was created to calculate boiler efficiencies.