Advanced Harmonic Transformer Calibration Solutions-Part 1

1. What Is Harmonic Transformer

1.1 Introduction to Harmonic Transformers

Fundamental Wave

Definition: According to IEC standards, the fundamental wave is "the first component of the Fourier series of a periodic quantity." In the Chinese power system, it typically refers to a sinusoidal wave with a frequency of 50 Hz.

Harmonics

Definition: Harmonics are "components of the Fourier series of a periodic quantity with orders higher than 1," encompassing integer harmonics, interharmonics, and subharmonics. Practically, harmonics usually refer to integer harmonics with orders higher than 1. Interharmonics are non-integer multiples greater than 1, and subharmonics are multiples less than 1.

Table 1-1 Common Power Waveforms

1.2 Harmonics and Power Metering

1.3 Harmonic Transformer

• Harmonic Voltage Transformers: Measure and transform high voltage.

• Harmonic Current Transformers: Measure and transform high current.

• Harmonic transformers are essential for extending the measurement range of electrical instruments and isolating high voltage and large current containing harmonics, converting them into manageable levels for measurement and control.

Table 1-2 Harmonic Voltage Transformer and Harmonic Current Transformer