Power Electronics for Smart Grid….

….The Practical StuffDr Nigel Jakeman

30th November 2016

PROPRIETARY

Electricity Distribution in the 21st Century

PROPRIETARY 2

Why Smart Grid?

• UK has an ageing Transmission & Distribution network• De-carbonisation of transport set to increase our demand for Electricity• Energy Supply is changing, becoming less controllable• Energy Efficiency driving a proliferation of non-linear loads, ie CFL

Why Consider Power Electronics?

Multi-Function solutions are possible to deliver numerous benefits and maximise the capacity of our existing assets

Power Electronics for LV Network Reinforcement

PROPRIETARY 3

• Numerous concepts available deploying common building blocks:

STATCOM

SOFT OPEN POINT

(SOP)

UNIFIED POWER FLOW CONTROLLER

(UPFC)

ENERGY STORAGE

VOLTAGE REGULATOR SOLID STATE TRANSFORMER

(SST)

+ -

Multiple Benefits Approach

PROPRIETARY 4

• PE solutions provide space saving & lightweight alternatives to traditional reinforcement enabling INSTALLATION IN CONSTRAINED AREAS:

• Functionality delivered AUTONOMOUSLY & DYNAMICALLY, to address the unpredictable effects of changing load cycles due to increasing DG and LCT take-up

But there are practical challenges to overcome…….

STATCOM UPFC Energy Storage

Voltage Regulator

SOP SST

Active Power Control - ++ ++ + D ++

Reactive Power Support ++ + + - A +

Power Factor Correction ++ - + - T +

Voltage Support + + + ++ U ++

Harmonic Elimination - - - - M -

Intelligent Energy Storage - - ++ - Option -

Example: FUN-LV Soft Open Point (SOP)

PROPRIETARY 5

Sub station 1

Sub station 2

PEC 1 PEC 2

Consumer Load 1

Consumer Load 2

FUN-LV converter

Supply 1 Supply 2

Power Electronic Converters (PEC’s) mesh networks and balance power flow

1. Loads balanced – SOP doesn’t conduct

2. Supply 1 supports Load 2 to de-load sub station 2

3. Excess generation supports load 2 to de-load sub station 2

SOP Practical Implementation

PROPRIETARY 6

Method 2 Method 3

• 240kVA – Dual Converter• Air Cooled• Street furniture

Challenges:• Public! – Security, Cooling, Noise

• 400kVA – Tri Converter• Water Cooled• Sub Station furniture

Challenges:• Enclosed space – Environment

TPS Soft Open Point Converter

PROPRIETARY 7

• Maximises existing asset capacity by improving utilisation Reduces load on stressed 3 phase line Reduces load on individual stressed phases – Unique hardware configuration Optimises voltage Reduces harmonic heating – Unique software controller Improves power factor

• Retains line fault clearance capability

• Parallel device that can be isolated

Balance between sub station A and B changed from 80%:20%

to 52%:48% with SOP

PE Challenges – Complexity & Practical Considerations

PROPRIETARY 8

• Complex with 1000’s of components

• Converters generate noise Audible Electrical (EMC)

• Converters generate heat Large if naturally cooled Noisy if force cooled Complex if liquid cooled

Sen

sors

What you think you need

Pro

tect

ion

EMC

filt

erFi

lter

Co

olin

g C

on

tro

l

Mo

re s

en

sors

Pow

er e

lect

ron

ics

Yet

Mo

re s

en

sors

System Control & Comms

What you actually need!

Power Electronics control

FUN-LV SOP learning

PROPRIETARY 9

• 24 field trials installed De-bugging and functional performance resolution System robust to grid variances

Remote programing essential when trialling a new product on such a scale!

• Issues Overcome During the Trials Synchronisation of PED Switching Elimination of phantom trips due to noise Cooling system loss in hot sub-stations Protection against thermal runaway

• Resolutions Outstanding Audible noise a consideration in sensitive locations (2 sites) EMC compliance for 7 & 10 phase unbalanced system

NoiseSoftware

Environment

Voltage Support & Losses - Distribution setup

PROPRIETARY 10

253V

230V

? 230V

Voltage Drop

SOP

SOP

Voltage Drop 1 Voltage Drop 2

Voltage support ineffectual

Voltage support effectual

1.

2.

To get the most out of your SOP consider distribution system operating points

Cheaper, Smaller, Cooler…….

PROPRIETARY 11

• Next Generation Switching devices now available to achieve enhanced performance & functionality: Ultrasonic operation to eliminate audible noise Smaller filters for reduced size & weight Simplified cooling requirements Allowance for EMC mitigation Higher efficiency Reduced PEC cost!

• Faster processing power to further reduce harmonic heating effects on the network assets: Counter heating effects of non linear- loads on transformer, ie CFL’s

Existing Filter can be simplified & shrunk3T Single PED

Something to Ponder…..

PROPRIETARY 12

What is a Smart Grid reinforcement Device?......

…….does it lead or does it follow?.......

…….what grid compliance methodology should be adopted?

PROPRIETARY