Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

What is Open Circuit Voltage?When an open circuit condition is created in any device or circuit, the difference of electric potential between the two terminals is known as the open-circuit voltage. In network analysis, the open-circuit voltage is also known as the Thevenin Voltage. The open-circuit voltage is often shortened to OCV or VOC in mathematical equations.In open-circuit conditions, the external load is disconnected from the source. An electric current will not flow through the circuit.

What is DC Voltage?DC voltage stands for “Direct Current Voltage”. While this sounds confusing, the term “DC” has become used more broadly to refer to a system that has constant polarity. Hence DC voltage is a voltage that produces or would produce a DC current. Conversely, an AC voltage is a voltage that produces or would produce AC current.DC in this context refers more broadly to quantities that don’t regularly change polarity or that have zero (or effectively zero) frequency. AC refers to qu

A voltage source is a device that provides a constant or varying electric potential difference between its terminals. A current source is a device that provides a constant or varying electric current through its terminals. Both voltage and current sources are essential for powering various electrical circuits and devices.However, not all sources are the same. Depending on how they behave and interact with other circuit elements, sources can be classified into two main categories: independent and

What is Nominal Voltage?Nominal voltage is a value assigned to a circuit or system to designate its voltage class conveniently(e.g. 120/240 volts, 300 volts, 480Y/277 volts). The actual voltage at which a circuit operates can vary from the nominal voltage within a range that permits satisfactory operation of equipment.The word “nominal” means “named”. It is not the precise operating or rated voltage. i.e. a 240-volt circuit may not be precisely 240.0000 volts, and may instead operate at 235.4 vo

What is Voltage?Voltage (also known as electric potential difference, electromotive force emf, electric pressure, or electric tension) is defined as the electric potential difference per unit charge between two points in an electric field. Voltage is expressed mathematically (i.e. in formulas) using the symbol “V” or “E”.If you’re looking for a more intuitive explanation to help explain what voltage is, skip to this section of the article.Otherwise, we’ll continue below with a more formal defini

What is RMS Voltage?The word RMS stands for Root Mean Square. An RMS voltage is defined as the square root of the mean square of instantaneous values of the voltage signal. The RMS is also known as the quadratic mean. RMS voltage can also be defined for a continuously varying voltage in terms of an integral of the squares of the instantaneous values during a cycle.The RMS value is most important in the case of an AC signal. Because the instantaneous value of an AC signal varies continuously with

A novel PET for a distribution grid called a flexible power distribution unit is proposed in this paper, and the energy exchange mechanism between the network and the load is revealed. A 30 kW 600 VAC/220 VAC/110 VDC medium-frequency isolated prototype is developed and demonstrated. This paper also presents key control strategies of the PET for electrical distribution grid applications, especially under grid voltage disturbance conditions. Moreover, stability issues related to the grid-connec

In this paper, an overall individual dc voltage (including high-voltage and low-voltage dc-link voltages) balance strategy is proposed for the electronic power transformer with separated dc-link topology. The strategy adjusts active powers flowing through the isolation and output stages in different power modules to enhance the dc voltage balance capability. Through the strategy, the high-voltage and low-voltage dc-links can be well balanced when unbalance occurs among different power modules

This paper proposes and analyzes a two-stage dc-dc isolated converter for electric vehicle charging applications, where high efficiency over a wide range of battery voltages is required. The proposed conversion circuit comprises a first two-output isolation stage with CLLC resonant structure and a second two-input buck regulator. The transformer of the first stage is designed such that its two output voltages correspond, ideally, to the minimum and maximum expected voltage to be supplied to th

Grid-forming (GFM) inverters are recognized as a viable solution to increase the penetration of renewable energy in bulk power systems. However, they are physically different from synchronous generators in terms of overcurrent capability. To protect the power semiconductor devices and support the power grid under severe symmetrical disturbances, the GFM control systems should be able to achieve the following requirements: current magnitude limitation, fault current contribution, and fault reco