In this month’s article the testing capabilities of RHM International’s new High Voltage Test Laboratory are discussed in more detail. The main purpose of the lab is to provide routine testing for RHM International’s manufactured products (bushings, current transformers, cable terminations) with nominal voltages up to 500-600kV. The lab also can perform high-voltage insulation tests for power/distribution transformers, reactors, insulators, etc.
Major Testing Equipment in the High Voltage Laboratory
| Equipment | Function | Description |
| Impulse Voltage Test System | Lightning/Switching Impulse voltage test for power apparatus. | Rating: 2800 kV/280 kJ, Lightning impulse Voltage 1.2/50 μs, chopping time 2-6 μs Switching impulse Voltage: 250/2500 μs. |
| AC (Power Frequency) Withstand Voltage Test System | Power frequency (50/60Hz) withstand voltage test for power apparatus, with PD measurement | Rating: 2000 kVA Rated voltage: 1000 kV Rated current: 2 A |
| HV Reference Capacitor | HV dielectric loss and capacitance measurement | Rating: 400 kV/100 pF |
| Partial Discharge Tester | Partial discharge measurement and recording | Sensitivity: 0.06 pC Can work with AC withstand voltage test system |
| Dissipation loss (PF/tan δ) & Capacitive (C) Tester | Measurement of Dissipation factor (or Power factor) and capacitance | Accuracy tan δ 1×10-5 Can work with AC withstand voltage test system and HV reference capacitor |
Impulse Voltage Test Set
The Impulse Voltage Test Set is composed of:
- An impulse voltage generator which has 14 stages and rated 2800 kV, 280 kJ;
- A low damped capacitive divider rated 2800 kV;
- A chopping device with 15 pairs of chopping gaps and rated 3000 kV;
- A computer measuring and control system installed in the control room.
AC (Power frequency) Withstand Voltage Test Set
The AC (Power frequency) Withstand Voltage Set is a company designed L-C resonant compensation system, which consists of:
- A reactor tower rating of 1100 kV/2 A with two taps;
- A capacitor rating of 2000 kVAR with three stages and a low-arm divider;
- An excltation transformer that can be in series and parallel connection, its rating is 200 kVA;
- A measuring and control system installed in the control room;
- The AC withstand voltage set can work with High Voltage Reference Capacitor and Dissipation loss (PF/tan δ) & Capacitive (C) Tester to conduct dissipation loss and capacitance measurement under 400 kV and below (with a planned future measurement capability under 600 kV and below);
- It also can work with PD tester to perform short-time dry/wet power frequency withstand voltage test with PD measurement.
How Does the RHM High Voltage Lab Compare with Other HV Lab Facilities in North America
Although other HV Labs can offer a broader range of testing services we feel that we compare favorably for similarly offered tests.
|
HV Lab Item |
RHM International |
DNV•GL KEMA - USA 1) |
Manitoba Hydro1)-Canada |
|
Dimension (LxWxH) |
28×28×17.5 (m) |
— |
41×38×19 (m) |
|
HV Test Capabilities |
Up to 500 kV current transformers, bushings & cable terminations | Up to 245 kV transformers and breakers | Up to 500 kV instrument transformer & bushings |
| Up to 245 kV cables, capacitors | Cables | Medium-voltage cables | |
|
Impulse voltage generator |
2800 kV·280 kJ |
1500 kV |
2400 kV·360 kJ |
|
Lightning impulse /kV |
2500 kV |
1250 kV |
2200 kV |
|
Switching impulse /kV |
1300 kV |
900 kV |
1300 kV |
|
AC withstand voltage equipment |
1000 kV·2A |
1200 kVA (600 kV·2A ) |
800 kV·5A |
|
60Hz AC withstand voltage /kV |
1000 kV (0-10nF) |
600 kV |
800 kV (0-14.5nF) |
|
PD measurement /background |
1000 kV (≤0.2pC) — MPD600 |
— |
800 kV (≤2pC) — MPD600 |
|
tanδ measurement |
600 kV 50 pF |
— |
600 kV 50 pF |
Note: 1) Reference to the company website.
