Braz de Jesus Cardoso Filho

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Mining process requires several types of mining pumps to transfer a fluid from one point to another in the process. In the majority of applications, those pumps are driven by variable speed motor drives in order to improve the energy efficiency of the overall system. Large pumps, ranging from hundreds of kW to a few MW, usually demand medium voltage(More)
This paper presents a case study of a medium voltage three-phase capacitor bank energization, based in an unsynchronized switching scheme using three independent pole vacuum switch simultaneously commanded. The motivations are cost reduction and simplification of the switching scheme. The maximum current and voltage peaks during transients caused by(More)
In underground mining industry, mineral transportation from lower levels to the surface is critical, thus demanding thorough equipment selection. The dc motor driven hoist dominated these applications, providing superior controllability. However, due to its increasing popularity, ac drive systems replaced dc application, including in mine hoisting. The high(More)
Power flow control in Electric Arc Furnaces (EAF) is inherent of the steel production process. The standard form is using an On-Load Tap Changer in the EAF transformer and controlling the arc length to achieve the desirable power in each stage of the scrap melting. An alternative to this system is the usage of a Thyristor Switched Series Reactor (TSSR).(More)
Voltage sag is one of the most frequent power quality problems found in industries and power system. Its effects can be numerous such as control equipment trips, process shutdown, production losses. This paper reports three year of voltage sag measurements collected in a research lab. This site is located near to many metal industries which lead to a(More)
Belt conveyors in mining industry constitute an efficient and economical way for minerals and heavy load transportation from mines to their destination. The ongoing desire to further extend the length, speed and capacity of the conveyors, has led to the increasing size of the conveyor drive systems. More and more frequently, high-capacity belt conveyors are(More)
This paper deals with the power quality improvements that can be achieved in mining industries by the employment of a high power active front end. A three-level neutral-point-clamped rectifier with low harmonic distortion and high power factor is chosen alternatively to diode rectifiers. A constraint on this class of converters is its lower switching(More)
Utility-Accessible External Disconnect Switch (EDS) is an AC switch used in electric power systems to disconnect Distributed Energy Resources (DER) from the main grid during maintenance. The EDS utilization is intended for line worker safety, since it is currently the only mechanism to ensure galvanic disconnection between DER and distribution network.(More)