Mitigation of ground loop effects in high-voltage measurements

Author

van Deursen, A.P.J. ; van Waes, J.B.M.

Author_Institution

Dept. of Electr. Eng., Eindhoven Univ. of Technol., Netherlands

Volume

51

Issue

3

fYear

2002

fDate

6/1/2002 12:00:00 AM

Firstpage

480

Lastpage

486

Abstract

Ground loops can affect voltage measurement systems, in particular those in high-power test circuits. The net or common-mode current through the signal cable shield induces interference in the signal circuit. A generalized transfer impedance Z_t describes this undesired coupling. In a low-frequency circuit model, Z_t decomposes into two terms which vary with the cable length l and with l ² respectively. Several divider setups are discussed; all employ the same high-voltage arm. The position and composition of the low-voltage arm vary. A proper design of the signal circuit ensures a low Z_t at the power frequency. Measurements confirm the model. With the low Z_t, the direct capacitive coupling between the high-voltage arm and neighboring circuits showed up as a comparable interference source

Keywords

cable shielding; earthing; electromagnetic compatibility; electromagnetic interference; high-voltage techniques; voltage dividers; voltage measurement; EM coupling; EMC; HV measurement; cable length; common-mode current; direct capacitive coupling; divider setups; ground loop effects mitigation; high-power test circuits; high-voltage arm; high-voltage measurement; interference; low-frequency circuit model; signal cable shield; signal circuit design; signal transfer; transfer impedance; voltage measurement systems; Cable shielding; Circuit testing; Coaxial cables; Coupling circuits; Frequency; Interference; Power cables; Switches; System testing; Voltage;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/TIM.2002.1017718

Filename

1017718