Power quality intelligent comprehensive optimization device with field temperature alarming function

Abstract

The invention provides a power quality intelligent comprehensive optimization device with a field temperature alarming function. A DVR (Dynamic Voltage Restorer) converter, a first DC capacitor and an APF (Active Power Filter) converter are in parallel connection to form a first compensation loop for voltage compensation; the DVR converter, a second DC capacitor and a second APF converter are in parallel connection to form a second compensation loop for harmonic processing and reactive power compensation; a load compensator is used for recording parameters such as starting, operation and removing of a specific load; a DC voltage fluctuation suppressor is used for suppressing DC voltage of the first DC capacitor and the second DC capacitor; and a network controller is used for controlling voltage compensation of the first compensation loop, controlling harmonic processing and reactive power compensation of the second compensation loop and providing a corresponding compensation algorithm according to a parameter change rule in the load compensator. Thus, voltage drop is compensated in the case of power grid voltage drop, harmonic processing and reactive power compensation are carried out in the case of no drop, the voltage fluctuation can be suppressed to acquire a high-quality output waveform, and the power consumption quality compensation speed is improved for the user.

Description

technical field [0001] The invention relates to the technical field of power systems, in particular to an intelligent comprehensive optimization device for power quality with an on-site temperature alarm function. Background technique [0002] UPQC (Unified Power Quality Conditioner, Unified Power Quality Conditioner) is usually composed of a series voltage source converter and a parallel voltage source converter through a common DC bus. It is installed near the harmonic load on the user side, which can Simultaneously compensate for voltage and current. The series voltage source converter acts as a DVR (Dynamic Voltage Restorer, dynamic voltage compensator), which can suppress voltage fluctuations, compensate power supply voltage harmonics, and eliminate voltage swells or voltage sags that often occur in power distribution systems. Increase the damping of the unit. The parallel voltage source converter plays the role of APF (Active Power Filter, active power filter), which...

AI Technical Summary

Problems solved by technology

[0004] During the working process of UPQC, it is necessary to coordinate the DVR function and the APF function. When there is a voltage drop, the DVR function starts. At this time, there are two options for the APF function: 1. Synchronously stabilize the voltage of the DC capacitor C1*, which is used for voltage drop compensation, but there are disadvantages The reason is: UPQC no longer has harmonic and reactive power compensation. When the series side is performing voltage compensation, the harmonics and reactive power of the grid will have peak values, and harmonic processing and reactive power compensation must be performed in time; 2. Compensate harmonics, The DC capacitor C1* voltage is no longer maintained, but the disadvantage is that the DVR compensation function is limited, because the DVR function is completed only by the energy stored in the DC capacitor C1* and its auxiliary energy storage device. When the energy is used up, the DVR compensation function ends until the DC voltage Allow C1* to return to normal state before the next DVR compensation action can be performed

[0005] Through retrieval, the Chinese Patent Publication No. CN 104393599 A discloses a unified power quality adjustment device and method, which solves the above problems well. However, in this solution, the inventor found that in the above two APF function selections , the voltage of DC capacitor C1* is easy to fluctuate, which is not conducive to obtaining high-quality output waveforms, and because the harmonic and reactive power characteristics of user loads are regular, users cannot obtain excellent compensation speed for power quality compensation

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