Rated voltage: 400kV (DC)
Rated current: 10mA
Rated resistance: 10kΩ
Structure: nichrome wire convolveon epoxy tube, two terminal contacts with divider.
Damping resistance include AC side protective resistance (Charging transformer) and DC side protective resistance.
AC side protective resistance 10kΩ, DC side protective resistance 10kΩ
Its place between DC generator and divider. Resistor’s resistance annual change less than 5%.
Resistance is movable and lockable.
Protection of Over-current and Over-voltage:
When DC device external load or system component breakdown or flashover, the system may happen over-current or over-voltage phenomenon.
HV silicon rectifier is the most weak component of the DC generator. When over-voltage or over-current happne, this component easy to be damaged.
Testing prove, load (test object) short circuit is the most serious situation of over-voltage and over-current.
If serial DC generator not equip current limit resistor, when load short circuit, the left pillar C1, C2 and C3 serial connection and pass D1, D4. The high discharge current will damage D1 and D4.But if serial one current limit resistor R1, and equip enough resistance, will enable limit the discharge current in acceptable range. But the discharge current will generate voltage drop, around R1, close to (n-1)Um. This voltage drop impact neighbouring D1, D4 and transformer HV winding, causing high over-voltage.
If serial connecting one protection resistor R0 between main body of generator and load, and R0/R1 big enough, the over-current and over-voltage can be limited in acceptable range.
When HV capacitor breakdown, HV silicon rectifier will also has over-current, e.g. capacitor C2 breakdown, D2 will has high over-current, in order to control the over-current, every HV silicon rectifier should connect with one current limit resistor R1.
HIMALAYAL provides innovative products that comprise high voltage test equipment, full-set high voltage test instruments, on-site test systems and on-line monitoring systems, and services regarding tests, diagnostics and asset monitoring for clients in power industry. We help to ensure safety and reliability in the power generation, transmission and distribution.