Siemens 7sg15 microtapp - Table of Contents

7SG15 MicroTAPP Description of Operation
©2013 Siemens Protection Devices Limited Chapter 1 Page 2 of 38
Contents
1
Introduction....................................................................................................................................... 4
2 Power system requirements............................................................................................................. 4
3 MicroTAPP Functionality.................................................................................................................. 4
3.1 Inputs.......................................................................................................................................... 4
3.1.1 Voltage Measurement........................................................................................................ 5
3.1.2 Current Measurement........................................................................................................ 5
3.1.3 Status................................................................................................................................. 5
3.2 Outputs ....................................................................................................................................... 5
4 Description of operation ................................................................................................................... 6
4.1 General....................................................................................................................................... 6
4.2 Transformers in Parallel ............................................................................................................. 8
4.2.1 Circulating Current Control ................................................................................................ 8
4.2.2 Negative Reactance circulating current control – TAPP ................................................. 10
4.2.3 Master/Follower control ................................................................................................... 11
4.3 Load Drop Compensation ........................................................................................................ 11
4.4 MT102 Advanced Features ...................................................................................................... 11
4.4.1 Description of Operation.................................................................................................. 11
4.4.2 Location of tap-changer, HV or LV side........................................................................... 12
4.4.3 Change in voltage per tap ............................................................................................... 12
4.4.4 Single phase or 3 phase units ......................................................................................... 13
4.4.5 Direction of tap-changer for voltage increase.................................................................. 13
4.4.6 Transformer impedance .................................................................................................. 13
4.4.7 Nominal voltage or winding load drop compensated target settings............................... 13
4.4.8 Dead-Reckoning Block .................................................................................................... 13
4.4 MicroTAPP–MicroTAPP communications................................................................................ 13
4.5 Low Frequency Voltage Reduction .......................................................................................... 13
4.6 Transformer Switch out ............................................................................................................ 13
4.7 Transformer Switch in .............................................................................................................. 14
4.8 Relay Settings .......................................................................................................................... 14
4.8.1 Basic Set-point.................................................................................................................14
4.8.2 Normal voltage deadband ............................................................................................... 14
4.8.3 Load Drop Compensation (LDC) ..................................................................................... 14
4.8.4 Circulating Current Compensation .................................................................................. 15
4.8.5 Tap Stagger .....................................................................................................................15
4.8.6 Time Delays for Operation............................................................................................... 15
5 Control............................................................................................................................................ 15
5.1 Control Points........................................................................................................................... 15
5.1.1 At the tap change mechanism ......................................................................................... 15
5.1.2 At the voltage control relay panel .................................................................................... 16
5.1.3 At a remote site................................................................................................................16
5.2 Control Switches ...................................................................................................................... 16
5.2.1 Local/Remote................................................................................................................... 16
5.2.2 Auto/Manual.....................................................................................................................16
5.2.3 Raise/Lower.....................................................................................................................16
6 Protection ....................................................................................................................................... 17
6.1 Voltage and Current ................................................................................................................. 17
6.1.1 Measured voltage outside normal range ......................................................................... 17
6.1.2 Voltage transformer faulty ............................................................................................... 18
6.1.3 Load Current....................................................................................................................19
6.2 Tap Changer ............................................................................................................................ 19
6.2.1 Tap Change Runaway..................................................................................................... 19
6.2.2 Tap Change Incomplete .................................................................................................. 20
6.2.3 Limit of Tap Change Range............................................................................................. 20
6.2.4 Tap Not Achievable ......................................................................................................... 20
7 Other Features ............................................................................................................................... 21
7.1 Instrumentation and Metering................................................................................................... 21
7.1.1 System ID ........................................................................................................................ 21