DC power supply is a device that maintains a stable voltage and current in the circuit.
The principle of DC power supply: The electric field caused by positive charges alone cannot maintain a stable current, but with the help of DC power supply, non electrostatic effects can be used (to make the positive charge return from the negative electrode with a lower potential difference to the positive electrode with a higher potential difference inside the switching power supply, in order to maintain the potential difference between the two levels and generate a stable current. DC power supply is a device that maintains a stable voltage and current in the circuit.
The non electrostatic force in a DC power supply is biased from the negative pole to the positive pole. When the DC power supply is connected to the external circuit, a current is generated from the positive pole to the negative pole outside the switching power supply (external circuit) due to the promotion of electric field force. In the internal circuit of a switching power supply, the effect of non electrostatic forces causes the current to flow from the negative electrode to the positive electrode, thereby creating a closed loop system for the flow of positive charges.
The main characteristic of a switching power supply is its electromotive force, which is equivalent to the work done by non electrostatic forces when the positive electrode of the enterprise moves from the negative electrode to the positive electrode based on the internal movement of the switching power supply.
When the internal resistance of a switching power supply can be ignored, it can be felt that the electromotive force of the switching power supply is numerically equivalent to the potential difference or operating voltage between the two aspects of the switching power supply.
In order to obtain a higher AC voltage, DC power sources are often applied in series. At this time, the total electromotive force is the sum of the electromotive forces of each switching power source, and the total internal resistance is also the sum of the internal resistances of each switching power source. Due to the expansion of internal resistance, it is usually only used in power circuits that require lower current intensity. In order to obtain a large current intensity, DC power sources with equal electromotive force can be connected in series. At this time, the total electromotive force is the electromotive force of the individual switching power sources, and the total internal resistance is the series value of the internal resistance of each switching power source.
There are many types of DC power sources, and the characteristics of non electrostatic forces and the entire process of energy conversion vary among different types of DC power sources. In chemical batteries (such as dry batteries, batteries, etc.), non electrostatic forces are oxidation reactions that are linked to the entire process of positive ion melting and accumulation. When chemical batteries are charged and discharged, mechanical energy is converted into electromagnetic energy and Joule heat in temperature difference switching power supplies (such as metal material temperature difference thermocouples, semiconductor material temperature difference thermocouples). Non electrostatic forces are diffusion reactions that are linked to temperature differences and concentration differences in electronic devices. When temperature difference switching power supplies output power to external circuits, a portion of the energy is converted into electromagnetic energy. In a DC generator, non electrostatic forces are electromagnetic effects. When the DC generator is powered by a system, chemical energy is converted into electromagnetic energy and Joule heat. In photovoltaic cells, non electrostatic force is the effect of photovoltaic power generation. When the photovoltaic system is powered, light energy is converted into electrical energy and Joule heat.
