How do you design electrical distribution systems for mining and mineral processing facilities?

2 Load analysis and demand factors

Another important step in designing electrical distribution systems for mining and mineral processing facilities is to conduct a load analysis and determine the demand factors for the various electrical loads. A load analysis is a calculation of the power requirements and consumption of the equipment, devices, and circuits that make up the electrical system. A demand factor is a ratio that reflects the probability of simultaneous operation of different loads. For example, a demand factor of 0.8 means that only 80% of the total load is expected to operate at the same time. Load analysis and demand factors help to size and select the appropriate transformers, generators, cables, switchgear, and protection devices for the electrical system.

3 Distribution voltage levels and configurations

A third step in designing electrical distribution systems for mining and mineral processing facilities is to choose the distribution voltage levels and configurations that suit the project needs and constraints. The distribution voltage level is the voltage at which the electrical power is delivered from the source to the load. The distribution configuration is the arrangement of the conductors, buses, and switches that connect the source and the load. For example, some common distribution voltage levels for mining and mineral processing facilities are 13.8 kV, 4.16 kV, 600 V, and 480 V. Some common distribution configurations are radial, ring, or network.

4 Grounding and bonding

A fourth step in designing electrical distribution systems for mining and mineral processing facilities is to ensure proper grounding and bonding of the electrical system. Grounding is the connection of the electrical system to the earth or a common reference point to provide a path for fault currents and to stabilize the system voltage. Bonding is the connection of all exposed metal parts of the electrical system to create a continuous low-impedance path for fault currents and to prevent electric shocks. For example, some common grounding and bonding methods for mining and mineral processing facilities are solidly grounded, resistance grounded, or ungrounded systems.

5 Power quality and harmonics

A fifth step in designing electrical distribution systems for mining and mineral processing facilities is to evaluate and mitigate the power quality and harmonics issues that may affect the system performance and reliability. Power quality is a measure of the deviation of the voltage, current, and frequency from their ideal values. Harmonics are distortion of the voltage and current waveforms caused by nonlinear loads, such as variable frequency drives, rectifiers, and arc furnaces. Power quality and harmonics issues can cause overheating, losses, malfunctions, and failures of electrical equipment and devices. For example, some common power quality and harmonics solutions for mining and mineral processing facilities are filters, reactors, capacitors, and active power conditioners.

6 Automation and monitoring

A sixth step in designing electrical distribution systems for mining and mineral processing facilities is to incorporate automation and monitoring features that enhance the system efficiency and safety. Automation is the use of control systems, such as programmable logic controllers (PLCs), to operate and regulate the electrical system without human intervention. Monitoring is the use of sensors, meters, and communication devices to collect and transmit data on the electrical system status and performance. For example, some common automation and monitoring functions for mining and mineral processing facilities are load shedding, load balancing, fault detection, protection coordination, and energy management.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?