An anti-shake module and its control method using bypass mode

Abstract

The invention relates to an anti-sway electricity module adopting a bypass mode and a control method thereof. The anti-sway electricity module includes a single-chip microcomputer, an electromagnetic relay, a solid-state relay, an energy storage capacitor group, an AC / DC switching power supply, a DC / DC power supply, a voltage A conversion chip, and an AC voltage sampler and a state detector whose two ends are respectively connected to the power grid and the single-chip computer signal; and the input and output ends of the AC / DC switching power supply are respectively electrically connected to the power grid and the energy storage capacitor group, and the energy storage capacitor group The output terminals of the relay are electrically connected to the single-chip microcomputer and the contactor through the voltage conversion chip and the DC / DC power supply respectively; the normally closed contacts of the electromagnetic relay are set on the power grid, and the normally open contacts and the normally open contacts of the solid state relay are connected in series in the DC power supply circuit superior. The contactor is supplied with alternating current and direct current during normal operation and swaying power, which not only solves the defect of pulsating DC start, but also maintains the contactor's pull-in, high reliability, and meets the operation requirements of the continuous production line.

Description

technical field [0001] The invention belongs to the technical field of anti-sway electric power system, in particular to an anti-sway anti-sway module in bypass mode and its Control Method. Background technique [0002] During the operation of the power system, due to lightning strikes, short-circuit to ground, fault reclosing, backup self-switching, external and internal power grid faults, large-scale equipment start-up, etc., the power grid faults caused by them will cause large instantaneous voltage fluctuations. Or short-term power failure and recovery, this phenomenon is called "shake power". [0003] There are mainly the following situations: [0004] (1) Sudden drop or rise in voltage, lasting for 0.5 cycle to 1 min, the voltage rises to 110-180% of the nominal voltage or drops to 10-90% of the nominal voltage. [0005] (2) Voltage flicker, the voltage waveform envelope shows a regular change or a series of random changes in the voltage amplitude, which generally m...

AI Technical Summary

Problems solved by technology

[0010] (2) Causes of tripping and shutdown caused by "power shaking"

[0011] With the development of the power grid, the continuous expansion of capacity and scale, the frequency of swaying electricity is increasing. Due to the increasing scale of production equipment in modern industrial and mining enterprises, although the duration of swaying electricity is relatively short, it has an impact on production. but very huge

Instantaneous voltage fluctuations will cause hundreds of motors to trip and equipment to shut down. After the power grid voltage is restored, the motors cannot resume operation by themselves, resulting in continuous production process disorder, and may cause production and equipment accidents

For large installations, it takes a long time to recover manually, and for some unattended field installations, the recovery time is even longer

For continuous production devices such as petroleum, chemical, and pesticide, a series of losses such as safety, environmental protection, waste products, waste of raw materials, reduced output, and low efficiency are very huge.

[0012] (3) The impact of shaking electricity on the motor of the power supply circuit

[0016] 1. Starting method: pulsating DC starting contactor is easy to burn out the contactor coil and device components; when pulsating DC starting contactor, when using a large-capacity contactor, the internal resistance of the contactor is very small (2 to 10 ohms); ( 1) It is easy to burn out the contactor: because the internal resistance of the contactor is small, when the pulsating DC voltage remains unchanged, the current through the contactor coil is very large (tens of amperes), which causes the contactor coil to be easily damaged; (2) easy to burn Device device: Because the device itself switches the higher pulsating DC to the DC voltage provided by the switching power supply by controlling the electromagnetic relay, the large current flows through the electromagnetic relay of the device; in this case, the control circuit part of the device The device is easy to burn out

[0017] 2. The principle of the control part: the control part is easy to burn out the contacts of the electromagnetic relay and the internal circuit board of the device, thereby reducing the service life of the device; (1) because the device uses an electromagnetic relay, most electromagnetic relay contacts have a DC capacity of on-off Not high, when the DC current flows through the electromagnetic relay contact greater than the rated value of the electromagnetic relay, the electromagnetic relay contact will appear "arcing" when it is released, so the electromagnetic relay contact often burns out, which may sometimes cause the electromagnetic relay to catch fire. Seriously, it will lead to fire; (2) If the electromagnetic relay burns out due to "arcing", there are two possibilities for the contacts of the electromagnetic relay. Dead on the same side (normally open or normally closed), the second possibility is: the contact of the electromagnetic relay connected to the live wire is "sticky" on the normally open side and the contact of the electromagnetic relay connected to the neutral line is "sticky" to the normally closed side. Or the contact of the electromagnetic relay connected to the live wire is "sticky" on the normally closed side and the contact of the electromagnetic relay connected to the neutral line is "sticky" to the normally open side; when the first case occurs, it only affects the device and cannot control the switching action, resulting in The anti-shaking function of the device fails; when the second situation occurs, the AC power and the DC power provided by the switching power supply are short together, which leads to circuit board burnout, device burnout, power supply circuit protection tripping, etc.

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