Electrical power management systems assure the safe and efficient operation of the electrical system. They help maintain the balance between power capacity and power consumption.
The features of a power management system have alleviated the difficulty to balance power supply and demand through the integration of renewable sources onto the grid. The instability and dynamics of renewable integration can be handled by a quality power management system.
The functions of a power management system include load-shedding, cost-optimization, enhanced support, active and reactive power control, grid stability, design optimization, and excellent communication links.
Power management systems can help manage the growing need for electrical power.
The demand for electrical power is growing, and so are the power-saving campaigns that are popping up all over the world. With such a high demand for electrical power, engineers must evaluate power systems with an eye on future impacts. Skilled and careful management becomes essential to managing the demand for power and avoiding monetary losses and system failures.
Electrical power management systems assure the safe and efficient operation of the electrical system. They maintain the balance between power capacity and power consumption, and are critical to improving the stability and reliability of commercial and industrial electric supplies.
Power Management Systems
Large consumers like refineries or the metal, chemical, and paper industries employ power management systems (PMS) to ensure a reliable and stable supply of electricity. In such power-demanding industries, a minor power issue can result in large losses. A PMS eliminates the chances of disturbances, brownouts, or blackouts and manages to meet the power requirements of the industry with the available supply.
A PMS monitors the economics associated with energy and tries to optimize the system operation as a step towards cost-effectiveness. A PMS also ensures electrical safety and environment-friendly operations. In short, a PMS handles the business, operational, and control aspects of electrical power in commercial and industrial systems.
Like industrial and commercial customers, a PMS benefits the electrical grid. Balancing power supply and demand has always been difficult with manual load dispatching, scheduling, monitoring, and operation. The features of a PMS alleviate this difficulty by facilitating the balance between supply and demand through the efficient integration of renewable sources onto the grid. The instability and dynamics issues of renewable integration can be handled by a quality PMS.
Functions of a Power Management System
Load-Shedding-In sensitive industries, the power demand is higher and critical loads are protected by the process of load-shedding. The critical loads are supplied power continuously and non-critical loads are supplied according to priority when there is a supply shortage.
Cost-Optimization-When the power demand of the industry tends to exceed the maximum demand, the industry will be penalized. The PMS will go for peak shaving by shedding non-critical loads, reducing the power demand.
Enhanced Support-The operator’s decisions are very important in power system control. PMS features such as alarms, human-machine interfaces, and consistency analysis support the operator and prevent them from making the wrong decisions.
Active and Reactive Power Control-In grid-connected distributed energy sources, the active and reactive power control improves the utilization of the power generated by the renewables. The locally generated power can be utilized for consumer needs—reducing the power consumption from the grid. The excess generated power can be sold to the utility company for financial benefits.
Grid stability-In a system with multiple generators, there are several contingencies where the system may fall to unstable operating conditions. The PMS operates the generators within stable limits.
Design optimization-The events of overload or overcurrent in the electrical network are eliminated by the PMS. This offsets the need for over-rating in the design of a generator, transformer, or circuit breaker.
Excellent communication links-The excellent communication in a PMS eliminates the need for the cable ducts or interposing relays typically required to transmit control signals of switchgear. It offers a single window for handling the readings, stored events, and data analysis.
Power Management Systems in Electric Vehicles
A PMS is an integral part of an electric vehicle (EV), marine vessel, or any other system which consumes electric power. Its main purpose is to control and manage the vehicle’s power consumption and increase its efficiency and performance. A PMS in an EV is modular in design and supported by software. Since vehicle manufacturers are keen on the up-gradation of vehicle models, a PMS can easily be updated to the next version with added features. The PMS in vehicles are capable of fostering power needs even when the complexity of vehicle architecture goes to the next level.
A quality PMS in an EV co-ordinates the battery and other auxiliary power supplies such as supercapacitors, solar panels, and fuel cells. Modern PMSs in EVs control the power consumption for extending the battery life by taking into account the terrain of the vehicle path. A PMS also improves mileage and the total efficiency of the EV.
The PMS of an EV consists of a smart control unit, a switching unit, a sensing module, and a DC-DC converter. The figure above shows the schematic of a PMS in EVs. The control unit processes the inputs given using microcontrollers and instructs the switching module to supply adequate power to the drive. The currents and voltages at the important nodes of the EV are sensed using the sensing module and the control unit forms the management tasks according to the sensed signals. In a PMS, the vehicle speed, input power, State-of-Charge(SoC) of battery, and supercapacitor are the inputs that determine the average power and energy requirements of the EV. Battery charging and discharging fluctuations are limited by following the PMS instructions.
For any engineering system where electric power supply influences the efficiency, performance, or cost of an operation, a PMS can be implemented. By using a PMS to control and manage power requirements, you get closer to attaining a reliable, stable, and efficient power solution in your system.