Reversible adjustment dynamic voltage adjuster

Abstract

The invention relates to a reversible adjustment dynamic voltage adjuster. The reversible adjustment dynamic voltage adjuster comprises a DSP control circuit, two PWM converters connected in series, and a sine wave filter which is in an inversion state and composed of inductors and capacitors. One end of an input voltage passes the secondary side of a series compensation transformer and then is output to a load through the sine wave filter, output of the first PWM converter is connected with the two ends of the primary side of the series compensation transformer, and output of the second PWM converter is connected with the front end of the load; An energy storage flat wave capacitor is connected between the two converters connected in series, the DSP control circuit acquires input voltage instantaneous values and input voltage phase signals, the DSP control circuit outputs control signals to the two PWM converters, and the working states of the two PWM converters are adjusted. Through two-way adjustment of energy, interference of fall and rise of network voltages in power consumers can be quickly restrained, and therefore the power quality of a power distribution system is improved.

Description

technical field [0001] The invention relates to a distribution transformer, in particular to a reversible adjustable dynamic voltage regulator. Background technique [0002] Since the power grid voltage and capacity change at any time, its voltage fluctuates greatly, manifested as frequent overvoltage and undervoltage, instantaneous drop, surge and spike interference (especially serious in some remote areas), thus affecting the quality of power consumption of users, and With the development of science and technology and economy, and the application of information technology and microelectronics technology, a large number of electrical equipment have higher and higher requirements for power supply quality. Studies have shown that the voltage drop problem has become one of the power quality problems that affect the normal and safe operation of many electrical equipment. In modern industrial production, voltage drop will cause the manufacturer's product quality to decline, and...

AI Technical Summary

Problems solved by technology

[0004] (1) Ferromagnetic resonant voltage stabilizer: It realizes voltage stabilization based on the principle of LS series resonance. This type of voltage stabilizer generally has low efficiency, low power factor on the power supply side, poor load adaptability, poor frequency effect, and temperature rise. High, noisy, bulky and other defects;

[0005] (2) Transformer ratio-adjusting voltage stabilizer: the transformer primary has multiple taps, and each tap is connected in series with a relay or bidirectional thyristor, and the voltage is adjusted by changing the taps. This voltage stabilizer can The thyristor or the relay is directly connected in series in the main circuit, and the load current flows through the thyristor or the relay. The transient and fluctuations in the load current can easily damage the thyristor, and a large amount of heat is generated by passing a large current for a long time. It also makes the thyristor work under harsh working conditions, deteriorating performance and poor reliability

Due to the use of carbon brushes and mechanical transmission, the working life is short, the response speed is slow, the contact surface of the carbon brushes is small and the output current is affected, the carbon brushes wear quickly and need to be replaced frequently, the mechanical failure causes the top to burn out the voltage regulator, and the power bureau replaces it. There are many shortcomings and problems such as the circuit causing the motor to reverse and burn out the equipment;

[0007] (4) Non-contact compensation AC voltage regulator: This topology has no mechanical contacts, small size, and high efficiency, which solves the defects of the above-mentioned models, as disclosed in patent No. ZL00204096.4 and patent No. ZL01253876.0 The non-contact AC voltage stabilizer; but the AC voltage stabilizer disclosed by these two patents has a common disadvantage that the voltage can be adjusted step by step, the voltage can not be continuously adjusted, and the voltage adjustment accuracy is not high.

In addition, when switching between different winding taps, it is easy to cause a short-circuit accident in which the thyristor is in common state

[0008] Patent No. ZL99244189.7 discloses a PWM inverter AC voltage regulator, which can realize continuous voltage regulation, but this topology is complex and difficult to control, so it is difficult to implement and the market value is not high

Images