Bincike da Kumbura na Kirkiya na Zama Lafiya da Kamar Yawancin Kirkiya da Hukumomin Su

1. Gargaɗi na Kompoonenti da Masu Laifi

TA (low-voltage current transformer) da meters na karkashin kirkiro suna cikin abubuwa masu muhimmanci a cikin karkashin kirkiro na low-voltage. Amfani da meters haka ana iya aiki ne a kan amfani da adadin ampere mafi yawan 60A. Meters na karkashin kirkiro suna da farko a fannon, model, da tushen kula da DC, kuma ana haske shi a kan wasu metering devices. Saboda rashin rashin kula da DC, suka samu matar da aka fi sani a kan laifukan da ke faruwa a kan DC components, wanda ake faruwa saboda non-linear loads. Da amfani da DC ko silicon-controlled equipment ya zama mafi yawa, musamman a tsarin elektrikal railroads da plastics industry, risa ta DC components ya zama mafi yawa. Binciken low-voltage anti-DC current transformers da detection devices yana da muhimmanci a kan hankalin wannan matsalolin.

2. Dalilai na Tashin Inaccuracy da TA Wajen DC Components

Rashin DC bias a cikin low-voltage current transformers ya faru daga tashin DC components a primary side. A fili, harmonics da DC ya faru suka haƙa transmission da metering, kuma lashe mutane a iron core ba su iya bayyana magnetic flux changes ba, wanda ya haɗa zuwa inaccuracy da TA. Amfani da half-wave current tests (32% of DC components are half-wave currents), magnetic permeability ya zama mafi yawa bayan primary winding, wanda ya haɗa zuwa inaccuracy (da negative shift, da ya zama close to saturation). Displacement of the secondary winding ya haɗa zuwa changes in waveform. Tests sun nuna cewa half-wave currents suka haƙa errors da suka zama mafi yawa a kan traditional transformers; kawo karamin DC components ita ce suka iya haƙa low-voltage anti-DC transformers, wanda suka zama mafi yawa da kadan da ake tabbatar da shi.

3. R&D na Anti-DC Low-Voltage Current Transformers

Low-voltage transformers na gari-gari sun amfani da annular magnetic cores (mainly amorphous ribbons, with high magnetic permeability, low saturation coefficients, and unaffected by primary-side DC). Iron-based amorphous cores, saboda hanyoyin magnetic permeability mafi yawa, ana amfani da shi a kan power transformers saboda iron loss mafi yawa. Su na initial magnetic susceptibility mafi yawa da coercivity mafi yawa, kuma su na tushen kula da DC. Electric waves from the secondary winding can restore the primary current waveform. By combining the complementary magnetic properties of iron-based amorphous and ultra-microcrystalline materials to form composite cores, the metering accuracy of traditional low-voltage anti-DC transformers can be improved.

4.Bincike na Tushen Kula da DC Performance Detection Methods

Anti-DC low-voltage current transformers na gari-gari suna da rashin lack of detection methods. Standards na gari-gari ba su standardize ba, kuma ba su iya judge ba da kuma rules and specifications da suka daɗe. Saboda haka, yadda ake yi tushen kula da DC performance detection method da kuma optimize shi yana da buƙata.

4.1 Comparison of electric energy

Ba da amfani da low-voltage current transformer, internal performance of the AC electric energy meter zai faru, kuma proportion of even harmonics zai faru. Don haka, half-wave rectification electric energy comparison test line ya zama kyau. Idan kana sauraro, half-wave rectification electric energy comparison method experimental line ya kamata a yi improvements based on the actual situation don haka za a iya ci gaba da tushen kula da DC performance of the low-voltage current transformer, wanda zai haɗa zuwa accuracy mafi yawa a kan electric energy detection.

4.2 1/1 self-calibration

Circuit diagram selected for this test is based on the data of JJ G1021-2007 "Regulations for the Verification of Power Transformers", and the details are shown in Figure 1.

Don haka a yi optimization of 1/1 self - calibration, the experiment rewinds the secondary winding with the same turns as the test low - voltage current transformer. This avoids error introduction from standard transformers. The circuit measures half - wave current and clarifies errors. Note: the current transformer in the circuit uses a 10/1 ratio to boost the verifier's current, so test values must be multiplied by 10 for accuracy.

Experiments prove this method effectively detects anti - DC performance, enabling circuit testing and self - calibration while avoiding measurement errors. However, rewinding is needed before measurement. Current and detection efficiency are inversely related: as current rises, efficiency plummets but labor intensity increases. Thus, half - wave DC composite error can't accurately reflect individual anti - DC performance.

5. Test Verification
5.1 Test Method

Simulating half - wave DC electricity theft by electric furnace users, the test installs three distinct energy metering devices. Repeated comparisons of performance results show manganin - resistance energy meters have superior anti - DC shunting ability, meeting on - site stability needs.

5.2 Test Data

Adequate prep, scientific plans, and pre - test site verification are key. During 80 - day assessments, energy is repeatedly compared/calculated, with detailed records.Results: Initial ordinary transformer meters show 40.08% relative error, rising to 90.58% after 80 days. Manganin meters keep errors ≤1% even in harsh conditions, while traditional devices exceed 90% over time. Enhancing anti - DC transformer research is vital for on - site demands.

6. Conclusion

The new composite - core low - voltage anti - DC current transformer accurately measures current, meeting standards even under DC loads. Unlike traditional designs, it retains familiar winding/pouring processes for easy promotion.DC - AC standard - based transformers offer strong operability, solving traceability issues and boosting detection accuracy.