Test Specification 01.01

Test Rationale

Verify that an on-load tap changer controller “OLTC” is able to regulate the voltage level of the distribution network to the required value as stipulated both by international standards and by the network operator

Specific Test System

Grid voltage levels may be defined in specific cases, but the MV range expected is 0-36Kv.

Target measures

• Voltage (V).
• Operation time (s).
• TAP position
• Number of TAP position changes

Input and output parameters

Inputs:

• Voltage (V)
• TAP position
• TAP direction (up/down)

Outputs:

• Voltage (V)
• Operation time (s)
• TAP position

Other:

• Number of TAP position changes
• Operation delay time (s)

Test Design

• Initialization of system (network, OLTC controller)
• Measurement of input parameters
• Calculation of optimal TAP position
• Output of optimal set points to voltage regulator
• Repeat

Initial system state

• System in steady-state at nominal grid voltage
• OLTC controller in ready state
• Communications established

Evolution of system state and test signals

Voltage signals monitored from start of experiment. Disturbances on the network are stabilized by changing tap position to return grid voltage level to within permitted grid voltage limits..

Other parameters

n/a

Temporal resolution

1ms

Source of uncertainty

Communication delays, power supply fluctuations

Suspension criteria / Stopping criteria

Uncontrollable abnormal system conditions, communications failures

Mapping to Research Infrastructure