CN210954179U

CN210954179U - Multipurpose frequency conversion cvt resonance device

Info

Publication number: CN210954179U
Application number: CN201921658192.XU
Authority: CN
Inventors: 周桂国; 朱明�
Original assignee: Wuhan Hance Electric Co ltd
Current assignee: Wuhan Hance Electric Co ltd
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2020-07-07
Anticipated expiration: 2029-09-30

Abstract

The utility model discloses a multipurpose frequency conversion cvt resonance device, including 0.1HZ alternating current power supply, electronic switch, step-up transformer I, step-up transformer II, ampere meter II, voltmeter II, piezo-resistor R1, ampere meter I, voltmeter I, AD analog-to-digital conversion circuit, main CPU, man-machine interface PLC touch screen, L reactor, tested article C1, tested article C2, overvoltage protection resistance R2 and 30-300HZ alternating current power supply, 0.1HZ alternating current power supply is connected with step-up parallel-pressure ware, and the intermediate position installs electronic switch, step-up transformer I's output is parallelly connected respectively with piezo-resistor R1 and tested article C1, ampere meter II establishes ties in step-up transformer I and piezo-resistor R1, voltmeter II connects in parallel at both ends of tested article C1; the device can alleviate intensity of labour, reduces the energy consumption, does not need large-scale equipment such as crane, once only can solve the problem that the cvt error boosts and withstand voltage, alleviates on-the-spot test personnel's operating time and the huge pressure of feeling relieved that high-voltage live operation brought.

Description

Multipurpose frequency conversion cvt resonance device

Technical Field

The utility model relates to a resonance test technical field, concretely relates to multipurpose frequency conversion cvt resonance device.

Background

At present, the resonant boosting method is most commonly used in testing cvt in power systems at 110kV or more (including 220kV 330kV 500kV 1000 kV). The traditional resonance pressure-rising manual adjustment inductance achieves system capacitance and inductance resonance. However, field workers cannot know the specific capacitance and inductance values, and only the inductance air gap can be adjusted manually. The working strength and the psychological pressure are both larger.

Disclosure of Invention

In order to solve the problem of the above existence, the utility model provides a multipurpose frequency conversion cvt resonance device.

The utility model discloses a realize through following technical scheme:

a multipurpose frequency conversion cvt resonance device comprises a 0.1HZ alternating current power supply, an electronic switch, a step-up transformer I, a step-up transformer II, an ammeter II, a voltmeter II, a piezoresistor R1, an ammeter I, a voltmeter I, an AD analog-to-digital conversion circuit, a main CPU, a human-computer interface PLC touch screen, an L reactor, a tested product C1, a tested product C2, an overvoltage protection resistor R2 and a 30-300HZ alternating current power supply, wherein the 0.1HZ alternating current power supply is connected with a step-up voltage combiner, the electronic switch is arranged in the middle of the 0.1HZ alternating current power supply, the output end of the step-up transformer I is respectively connected with the piezoresistor R1 and the tested product C1 in parallel, the ammeter II is connected in series in the step-up transformer I and the piezoresistor R1, and the voltmeter II is connected in parallel at two ends of the; the ammeter II samples a current signal, and the voltmeter II samples a voltage signal and then respectively transmits the signals to the main CPU through the AD analog-to-digital conversion circuit; the main CPU is connected to an external human-computer interface PLC touch screen, an internal circuit of the human-computer interface PLC touch screen is connected with an L reactor, the L reactor is installed at the output end of the step-up transformer II and is connected with the overvoltage protection resistor and the ammeter I in series, and the voltmeter I and the tested object C2 are also respectively connected with two ends of the overvoltage protection resistor R2 in parallel; the ammeter I samples a current signal, the voltmeter I samples a voltage signal and then respectively transmits the signal to the main CPU through the AD analog-to-digital conversion circuit, and the main CPU calculates the power frequency and transmits the power frequency to the 30-300HZ alternating current power supply, so that the alternating current power supply with the required frequency is selected.

Furthermore, the L reactor is formed by connecting 8 groups of same inductors and electronic switches in parallel, the electronic switches of each group are in an off state, and the electronic switches are automatically selected to be closed according to requirements.

Furthermore, an electronic switch is also arranged between the step-up transformer II and the 30-300HZ alternating current power supply, and when the input voltage or current is overlarge, the electronic switch automatically disconnects the protection alternating current power supply.

Compared with the prior art, the beneficial effects of the utility model are that: the real capacitance of cvt is tested by adopting a frequency conversion method, and then the corresponding inductance is selected by adopting a table look-up method according to the real capacitance. The device can reduce labor intensity, reduce energy consumption, does not need large equipment such as a crane and the like, can solve the problems of cvt error boosting and pressure resistance at one time, and reduces the working time of field test personnel and huge mental pressure caused by high-voltage live operation.

Drawings

Fig. 1 is a schematic connection diagram of a multi-purpose variable frequency cvt resonance device.

Detailed Description

The invention will be described in further detail with reference to the following detailed description and accompanying drawings:

as shown in fig. 1, a multipurpose frequency conversion cvt resonance device comprises a 0.1HZ alternating current power supply, an electronic switch, a step-up transformer i, a step-up transformer ii, an ammeter ii, a voltmeter ii, a piezoresistor R1, an ammeter i, a voltmeter i, an AD analog-to-digital conversion circuit, a main CPU, a human-computer interface PLC touch screen, an L reactor, a tested object C1, a tested object C2, an overvoltage protection resistor R2 and 30-300HZ alternating current power supply, the 0.1HZ alternating current power supply is connected with a step-up voltage combiner, an electronic switch is installed in the middle position, the electronic switch protects the alternating current power supply when the input voltage or current is too large, the output end of the step-up transformer i is respectively connected in parallel with a piezoresistor R1 and a tested object C1, the ammeter ii is connected in series with the step-up transformer i and the piezoresistor R1, and the voltmeter ii is connected in parallel with both ends of the tested object C1; the ammeter II samples a current signal, and the voltmeter II samples a voltage signal and then respectively transmits the signals to the main CPU through the AD analog-to-digital conversion circuit; after the main CPU calculates the numerical value of the tested sample C1, the matching L reactor is automatically selected, and meanwhile, the L reactor is formed by connecting 8 groups of same inductors and electronic switches in parallel. The main CPU is connected to an external human-computer interface PLC touch screen, an internal circuit of the human-computer interface PLC touch screen is connected with the L reactor, the L reactor is installed at the output end of the step-up transformer II and is connected with the overvoltage protection resistor and the ammeter I in series, and the voltmeter I and the tested object C2 are also respectively connected with two ends of the overvoltage protection resistor R2 in parallel; the ammeter I samples current signals, the voltmeter I samples voltage signals, and then the signals are respectively transmitted to the main CPU through the AD analog-to-digital conversion circuit, and the main CPU calculates power frequency and transmits the power frequency to the 30-300HZ alternating current power supply. An electronic switch is also arranged between the step-up transformer II and the 30-300HZ alternating current power supply, and when the input voltage or current is overlarge, the electronic switch automatically disconnects the protection alternating current power supply.

According to the electrical theory, when XL = XC in the line, the circuit reaches a resonance condition, where the required power supply capacity in the circuit is minimal. The working principle of the utility model is as follows:

1: when in test, the AC power supply of 0.1Hz is firstly output. The voltage rises to 2-10% of the rated voltage.

2: the device collects the current (I) and voltage (U) of an ammeter II and a voltmeter II. The capacitance of the system can be calculated from I = U × 2 × pi × 0.1 × C.

3: if cvt error tests are performed, L can be calculated from ω = 1/(L × C) knowing C, ω =2 × pi × 50. After calculating L, the device automatically looks up the inductance L corresponding to the scale. The test can be started after one-time direct adjustment.

4: if a cvt pressure resistance test is carried out, the most appropriate L is obtained by looking up a table by the instrument according to omega = 1/(L C) and C. It is known L C that the power frequency f can be calculated by calculating ω, ω =2 × pi × f according to the above formula. The ac power supply directly outputs a voltage of a corresponding frequency, and the test is started.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the foregoing embodiments and descriptions are provided only to illustrate the principles of the present invention without departing from the spirit and scope of the present invention.

Claims

1. A multipurpose frequency conversion cvt resonance device is characterized in that: the device comprises a 0.1HZ alternating current power supply, an electronic switch, a step-up transformer I, a step-up transformer II, an ammeter II, a voltmeter II, a piezoresistor R1, an ammeter I, a voltmeter I, an AD analog-to-digital conversion circuit, a main CPU, a PLC touch screen of a human-computer interface, an L reactor, a tested product C1, a tested product C2, an overvoltage protection resistor R2 and a 30-300HZ alternating current power supply, wherein the 0.1HZ alternating current power supply is connected with a step-up voltage combiner, the electronic switch is arranged in the middle of the 0.1HZ alternating current power supply, the output end of the step-up transformer I is respectively connected with the piezoresistor R1 and a tested product C2 in parallel, the ammeter II is connected in series in the step-up transformer I and the piezoresistor R1, and the voltmeter II is connected; the ammeter II samples a current signal, and the voltmeter II samples a voltage signal and then respectively transmits the signals to the main CPU through the AD analog-to-digital conversion circuit; the main CPU is connected to an external human-computer interface PLC touch screen, an internal circuit of the human-computer interface PLC touch screen is connected with an L reactor, the L reactor is installed at the output end of the step-up transformer II and is connected with the overvoltage protection resistor and the ammeter I in series, and the voltmeter I and the tested object C2 are also respectively connected with two ends of the overvoltage protection resistor R2 in parallel; the ammeter I samples current signals, the voltmeter I samples voltage signals, and then the signals are transmitted to the main CPU through the AD analog-to-digital conversion circuit, and the main CPU calculates power frequency and transmits the power frequency to the 30-300HZ alternating current power supply.

2. A multi-purpose variable frequency cvt resonator device according to claim 1, characterized in that: the L reactor is formed by connecting 8 groups of same inductors and electronic switches in parallel.

3. A multi-purpose variable frequency cvt resonator device according to claim 1, characterized in that: an electronic switch is also arranged between the step-up transformer II and the 30-300HZ alternating current power supply, and when the input voltage or current is overlarge, the electronic switch automatically disconnects to protect the alternating current power supply.