CN-122026288-A - Harmonic elimination device with self-monitoring function and monitoring method

CN122026288ACN 122026288 ACN122026288 ACN 122026288ACN-122026288-A

Abstract

The application discloses a resonance elimination device with a self-monitoring function and a monitoring method, which relate to the technical field of resonance elimination devices, and comprise two zinc oxide resistors which are connected in parallel, a temperature acquisition module and a controller, wherein a breaking switch is connected in series with a branch where each zinc oxide resistor is positioned, the controller can control the closing and opening of the breaking switch, the temperature acquisition module is used for acquiring temperature information of the zinc oxide resistor, the output end of the zinc oxide resistor is grounded, and a current transformer is arranged on a grounding line of the zinc oxide resistor. The application has the effect of being convenient for monitoring the performance degradation condition of the resonance elimination resistor.

Inventors

Sang Xinfeng
WANG LIYOU
LIU YONG
LI FUQIANG

Assignees

三立智能电气有限公司

Dates

Publication Date: 20260512
Application Date: 20260414

Claims (8)

1. The harmonic elimination device with the self-monitoring function is characterized by comprising two zinc oxide resistors which are connected in parallel, a temperature acquisition module and a controller, wherein a breaking switch is connected in series to a branch where each zinc oxide resistor is located, the temperature acquisition module is used for acquiring temperature information of the zinc oxide resistor, the controller can control closing and opening of the breaking switch and analyze the temperature information collected by the temperature acquisition module, the output end of the zinc oxide resistor is grounded, and a current transformer is arranged on a grounding wire of the zinc oxide resistor.
2. A method for monitoring a resonance elimination device based on the self-monitoring function of claim 1, comprising: After any zinc oxide resistor is switched, temperature fluctuation information, a preset initial temperature value and a preset termination temperature value of the zinc oxide resistor are obtained; Based on the temperature fluctuation information, generating a temperature fluctuation curve by taking time as a transverse axis and taking a temperature value as a longitudinal axis; in a cooling curve of the temperature fluctuation curve, initial time corresponding to an initial temperature value and termination time corresponding to a termination temperature value are matched; generating the actual temperature decay time of the zinc oxide resistor based on the initial time and the termination time; acquiring switching times and a theoretical temperature decay table of the zinc oxide resistor; the theoretical temperature decay time length corresponding to the switching times is matched in the theoretical temperature decay table; And if the actual temperature decay time is longer than the theoretical temperature decay time, generating alarm information.
3. The method for monitoring a resonance elimination device according to claim 2, wherein after the actual temperature decay time is longer than the theoretical temperature decay time, the method comprises: Acquiring the temperature decay time of the other zinc oxide resistor corresponding to the switching times; if the difference between the control temperature decay time and the actual temperature decay time is larger than the preset temperature decay time error, generating alarm information.
4. The method for monitoring a resonance elimination device according to claim 3, wherein the obtaining another zinc oxide resistor after the corresponding contrast temperature decay time of the switching times comprises: If the other zinc oxide resistor does not have the switching times, acquiring the switching temperature decay speed of the zinc oxide resistor, the current switching times of the other zinc oxide resistor and the reference temperature decay time of the other zinc oxide resistor under the current switching times; calculating the estimated temperature decay time of the other zinc oxide resistor reaching the switching times based on the reference temperature decay time, the switching times, the current switching times and the switching temperature decay speed; and if the actual temperature decay time of the zinc oxide resistor reaches the estimated temperature decay time of the other zinc oxide resistor, generating alarm information.
5. The method of claim 4, wherein the estimated temperature decay time is calculated by the following formula: ; Is the estimated temperature decay time of the other zinc oxide resistor in the switching times, Is the reference temperature decay time of the other zinc oxide resistor at the current switching times, Is the switching times of the zinc oxide resistor, Is the current switching times of another zinc oxide resistor, Is the switching temperature decay speed.
6. The method of claim 4, wherein the calculating the switching temperature decay rate comprises: acquiring a preset sampling period; according to the sampling period, acquiring the first temperature decay time of the zinc oxide resistor after the first switching in each sampling period and the last temperature decay time of the zinc oxide resistor after the last switching in each sampling period; calculating the period temperature decay time of each sampling period based on the first temperature decay time and the last temperature decay time of each sampling period; calculating the switching temperature decay speed in the sampling period based on the period temperature decay time of the zinc oxide resistor and the sampling period; Setting a switching span interval of each sampling period based on the first switching times and the last switching times of each sampling period; Establishing a mapping relation between a switching span interval and a corresponding switching temperature decay speed; And matching the switching span interval to which the current switching times belong based on the current switching times of the other group of zinc oxide resistors, and obtaining the switching temperature decay speed of the matched switching span interval.
7. The method of claim 6, wherein the period temperature decay time is calculated by the following formula: ; Is the period of time of temperature decay, Is the last temperature decay time in the sampling period, Is the first temperature decay time in the sampling period, Is the sampling period of time that is required for the sample, Is the last switching times of zinc oxide resistor in each sampling period.
8. The method of claim 6, wherein the switching temperature decay rate is calculated by the following formula: ; Is the switching temperature decay speed of the sampling period, Is the period of time of temperature decay, Is the sampling period.

Description

Harmonic elimination device with self-monitoring function and monitoring method Technical Field The application relates to the technical field of harmonic elimination devices, in particular to a harmonic elimination device with a self-monitoring function and a monitoring method. Background The voltage transformer is key equipment for voltage measurement, protection and automatic control in a power system, has the core functions of voltage conversion, electrical isolation and signal transmission, provides safe and accurate voltage signals for measurement, protection and control equipment, and is commonly arranged on an outgoing line side of a transformer, a high-voltage bus side of a transformer substation and the like. In the running process of the voltage transformer, as the characteristics of nonlinear elements in the voltage transformer can cause ferromagnetic resonance phenomenon when single-phase grounding faults, lightning overvoltage, line switching and other conditions occur, the possibility of occurrence of phenomena such as capacitor bank burnout and transformer damage is increased, so that in order to reduce the influence of the ferromagnetic resonance phenomenon on electric equipment, harmonic elimination resistors (usually zinc oxide resistors) are usually arranged on the grounding line of the neutral point of the voltage transformer, when the ferromagnetic resonance phenomenon occurs, the voltage on the grounding line of the voltage transformer is rapidly increased, the resistance value of the harmonic elimination resistors is converted from a high-resistance state to a low-resistance state, and after the harmonic elimination resistors consume part of resonance current, the residual resonance current is connected to the ground through the grounding line, so that the ferromagnetic resonance phenomenon is restrained. After the resonance elimination resistor is put into use, along with the increase of the frequency of inhibiting the ferromagnetic resonance phenomenon, if the continuous overvoltage can accelerate to destroy the resistor wafer boundary layer in the resonance elimination resistor, the performance of the resonance elimination resistor is degraded, once the resonance elimination performance of the resonance elimination resistor is seriously degraded, the overvoltage fault caused by the ferromagnetic resonance phenomenon is difficult to effectively inhibit, and the damage risk of electric equipment is increased. Disclosure of Invention In order to facilitate monitoring of performance degradation of the resonance elimination resistor, the application provides a resonance elimination device with a self-monitoring function and a monitoring method. In a first aspect, the present application provides a harmonic cancellation device with self-monitoring. The application provides a resonance elimination device with a self-monitoring function, which adopts the following technical scheme: The utility model provides a harmonic elimination device with from monitoring function, includes two relevant parallelly connected zinc oxide resistance, temperature acquisition module and controller, every zinc oxide resistance all establishes ties and has a break switch in branch road, temperature acquisition module is used for gathering the temperature information of zinc oxide resistance, the controller can control break switch's combined floodgate and break brake, analysis temperature acquisition module collection temperature information, the output ground connection setting of zinc oxide resistance just be provided with current transformer on the earth connection of zinc oxide resistance. The operation and principles of the present device are described in detail in the detailed description. In a second aspect, based on the above-mentioned resonance elimination device with the self-monitoring function, the application further provides a monitoring method of the resonance elimination device. A method of monitoring a detuning device, comprising the following processing steps: After any zinc oxide resistor is switched, temperature fluctuation information, a preset initial temperature value and a preset termination temperature value of the zinc oxide resistor are obtained; Based on the temperature fluctuation information, generating a temperature fluctuation curve by taking time as a transverse axis and taking a temperature value as a longitudinal axis; in a cooling curve of the temperature fluctuation curve, initial time corresponding to an initial temperature value and termination time corresponding to a termination temperature value are matched; generating the actual temperature decay time of the zinc oxide resistor based on the initial time and the termination time; acquiring switching times and a theoretical temperature decay table of the zinc oxide resistor; the theoretical temperature decay time length corresponding to the switching times is matched in the theoretical temperature decay table; And if the