HELLAS RECTIFIERS BV

FEMTOGRID ES BVWE ARE DCIFYING THE WORLD

MAKING DC SYSTEMS BY CONNECTING SOURCES & LOADS

DIRECT CURRENT BV

LVDC standardization and use cases in the Netherlands

Direct Current BV

Why DCWe are already

live in a DC world

Everything we and is DC

DC brings fun, comfort, clean and sustainable solutions

Me

ACTIVITY

Owner of the following Companies:

• DC. Systems LtD

• Direct Current LtD

• Hellas Rectifiers LtD

• Amstel Rectifiers LtD

• Femtogrid ES LtD

• DC Hortilighting LtD

• DOE-DC LtD

Foundations

• Founder of the DC Foundation

• Founder of Current/OS Foundation

Skills

• Started in 1988 as a DC entrepreneur. Building and creating DC systems for industrial application

• Energy systems

• Power Electronics

• High Current technology up[to 30kA

• ICT firmware/software

• Grid regulations

• DC System integration

• DC Applications

• DC Industrial processes

• DC and corrosion

BACKGROUND

• Protecting the Dutch Water defense against corrosion

• Green deal

Enabling a outdoor DC grid

• Universities

Active in the TU/Delft supporting the faculty DC and storage

CVCOMMISIONS

Commissions

• IEC LVDC SyC CAG, WG1 Convener WG2 LVDC Sycin the IEC for use cases public domain

• SyC LVDC liaison officer for TC8-WG9

• IEC TC 61200 PT101/102 TC64

• Convener Working group DC TC64 (NEN 1010) NPR9090

• Political active in regulation in the Netherlands

• CIGRÉ SC 6.31 MVDC distribution

Contact

Harry@dc.expertwww.directcurrent.euwww.dc.systems

I’m Dyslectic, so forgive me for spelling mistakes

Runner up

Why grids are important

• The electricity grid is one of the most value assets the society owns, and we become fully depended on it.

• It give us:• Energy• Hygiene• More dense society • It’s the fundament of the economy• Solution to sustainable systems• Economics

• We must protect is and make it simple as possible• It’s not about the business case only but it’s about our

continuity in life. It’s a social use case that facilitates business cases. This is crucial for electrical access

A vision is needed to secure our system (Dutch system)• Heating on gas. The decided

to reduce gas heating and move to heat pumps

• EV charging become already a topic into the current system• 750 fast charger installed• 75k home charging installed• 32k public chargers installed

Everything is also possible in AC

• The discussion is not • Efficiency (nice to have)

• Can not be done in AC

• But it makes more sense to do this in DC because• It’s about reduction of complexity

• It’s about reliability

• It’s about a full electronic system

• It’s about predicting the system

• It’s about raw materials

• Having a high share of renewables in the system

• It’s about increasing power levels in the last mile or application with smaller connections

It’s not all about system efficiency, but about an efficient system.

DC leads to challenges for AC

• Who has ever written a use case for AC.

• For DC we face the following challenges:• Everything must be a business case from start, there are also social use cases• Only focusing on efficiency will kill the DC use case (it’s nice to have but not a driver)• It’s about systems not single applications• Different systems (Active DC enables new use cases)• Complexity moves from system level to components level

• High challenges for AC for future systems:• Chapter 1 installation standards TC64 must be rewritten to create a new bidirectional

architecture, this will impact a lot of other inherited standards.• How to deal with history and mixed systems• Design of installations are based on rules of thumb • Systems become more complex with simple components

DC Systems are isolated from AC system

System level thinking

• Why the systems are complex• Not in my backyard• I don’t care it’s not my problem• It not a business case for me• It worked in the past• Very expensive to try• covering multiple area’s (multi discipline)

Production

Netwerk

Consumption Prosumers

Optimize

Optimize Optimize

Optimize

Mis

sin

g

• We have an AC system• Most R&D is spent on optimization of

components

• Most engineers are specialists

How systems grow

Public Services Storage Generate

Developed

country

MVAC/LVAC

Homes

AC/DC

Commercial

buildings

Developing

country

Lighting

Ventilation

Communication +ICT

Cooling by fans

Fridge

Solar

Simple Induction stove

HVAC

Cooking

Au

tark

icG

rid

PowerSolar

Small Storage

Create

Hot water

HVAC

Hot water

Cooking

EV Charging

Ventilation

Solar

ICT

EV Charging

Bus Stations

5G Network

Public Lighting

Road directions

Central Storage

Solar sound walls

Solar Farms

DC Entry

DC Future

Lighting

Solar

Storage

Public Light

Small Storage

Solar

Large storage

Future proof

Create

compatibility

Low High

Traffic guidance

Future disconnect Future disconnect

EV Charging

AC expansion or

move to

2e micro DC grid

Driver is different in

every country

Solar

Electric busses

Nothing

Expansion

GRID

Central Storage

Au

tark

ic

Ava

ilab

le

De

centr

al

Bala

nce

d

All e

lectr

ic

Water management

Farming

Future disconnect

Water pumping

Large Solar

Grow lights

Large Solar

Large scale EV parking

Solar Farms

Small Storage

Solar

Water pumping

© 2017 Harry Stokman

Phone charging

Water pumping

DC Grid

standards

DC

Application

standards

Interface

Developed country

DC Micro grid

MVDC/LVDC

Curr

en

t A

C g

rid

• Start is easy

• Next step more difficult

• Face the consequences of decisions

• Rethink the system with lessons learned

• The final system

USE Cases working group WG2 in the IEC LVDC SyC

• Use cases are important

• No standard without use cases

• Use cases must be a reference case to become valid for other use cases

• Collection use cases

• Regulation is part of it

Work in the TC s

Collecting UC s

Analysing UC s

Refrence UC s

Identifying gaps

Testing against Reference UC

Testing against UC

Analysing the deployment

WG2

Analysing of NWI

Need

Standards

LVDC SyC

Dutch “Polder” modelit’s one of the most reliable system fore more than 1000 years

• DC microgrids analogy is water management

• Prevent system failures

• Drive local decisions

• The decision maker faced the consequences

• Autonomous from the politics

• Low central control

LVDC ROLESStandards and Regulation

SUB GRID

DC

DC

DC

DC

SUB GRID

DC

DC

DC

DC

DC

DCDC

DC

DC

DC

DC

DC

±700V/±350V ±700V/±350V

±750V

DSO || MGO DSO || MGO

DNO

DC

DC

DC

USER

USERUSER

DC

USER

DC

USER

DC

USER

DC

USER

DC

USER

DC

USER

DC

USER

MAIN DISTRUBUTION GRID

WIDER SYSTEM

LVDC

MVDC || MVAC

HVDC || HVAC

TNO and TSO• Regulations

influences standards and standards influences regulation

• To make DC system successful in the public domain regulation and standards must match.

• Last change for a common world wide compatible system

• DSO and MGO are enabled

The most beautiful properties of DCwhat is Current/OS

SENSORGPS

COMSTEERING

BREAK

SPEED

SENSORGPS

COMSTEERING

BREAK

SPEED

Remote computersCAR Driving Software

SENSORGPSComputer

CAR Driving

software

STEERING

BREAK

SPEED

SENSORGPSComputer

CAR Driving

software

STEERING

BREAK

SPEED

OR !!

Realtime Centralized Control

Realtime Local Autonomous Control

© 2018 Harry Stokman

A Smart grid without ICT for control it will bring:• Trust• Privacy• Availability• Autonomous

Current/OS Properties

• Grounding system

• Priority by parameters

• Realtime without ICT Voltage driven

• Black start protocol

• Safety wire

• Grid synchronization protocol

• DC Zones defined now part of the Dutch TC64 NPR9090

• Protection based on the DC Zones

• Direct touch protection

• Full replacement of existing AC

solutions in many applications

• Must work in all applications, with compatibility

• Arcing

• Corrosion

• Selectivity 100% in Zone 3 and 4

• Voltage 350V/700V/1400V

• Emergency states

• Congestion management

4

0

Collaboration in Current/OS

We working hard to get consensus in the industry.

• Eaton: Protection

• Signify (Philips): LED drivers

• Nexans Cables for 350V/700V, grounding, safety wires and communication integrated

• ATAG induction stoves

• And other SME’s

DC Outdoor lighting ±350VDC

• Outdoor (we started this because it’s innocent, but can be expanded)• 240 km Public lighting installed in the Netherlands with as result:

• New use cases 5G and Smart cities line length up to 3.5km

DC Public service bus Second grid (Masterplan)

Bipolar DC grids running on ±350Vdc and 700Vdc for last mile replacement

Keep the existing

investment alive

Electrical Future system at the

lowest social cost

Enable new servicesDSO, Healthcare,

mobility

DC and footballcurrent project in progress

Large Event centers

AC

DC

com

com sw

10KV630KVA500KW

10KV630KVA500KW

32x200W700V

HBDC

DC

com sw

com

64kW100A

32x200W700V

HBDC

DC

com sw

com

64kW100A

10x

32x200W700V

HBDC

DC

com sw

com

64kW100A

32x200W700V

HBDC

DC

com sw

com

64kW100A

10x

AC

DC

com

com sw

© 2019 Harry StokmanDC

S1 S2

DC

500VEV-CCS

6kW

com SW

EV-CCS Q2

DC

DC

boost

buck

com sw

bms

BM

S

bms

DCbms

AC

DC

com

com

sw

10

KV

63

0K

VA

50

0K

W

700VDC +L/M/PE/SG/SW/COM

700V LED Drivers

100A Connectors 2 5mm2

AC

DCcom

UPSFor existing AC

grid

AC

DCcom

UPSFor existing AC

grid

• Grass grow light LED 700VDC 850kW

• 2x500kW AFE’s

• Expansion to 700V PV

• Event Backup between different AC transformers

• Future structure for EV

• Serving football, concerts and Dancing events.

DC in Tunnels (Rotterdam A16 highway)

• It’s about availability

• System availability during Maintenance

• Redundant without high investment

First version

• 3x 50kW Active Front Ends. Driving 150kW DC bus managed by the Current/OS protocol

• 535x 280W panels connected to DC micro converters

• 15x 16A/350V Current Routers protection

• 30kW LED lighting directly to DC

• 10kW Ventilation directly to 350V

• 6x 2500W AC 230V from the 350V DC

• Current/OS congestion

• Connection• 48x USB-C 100W

• 48x USB-A

• 48x 350V 10A sockets

DC

AC

3PH 400Vac

AC is an option

Safety Wire for Protection 48V DC

350V DC3x50kW

DC

AC

535x

48x 48x

100W

USB-C

USB-A

3kW

350V

Current/OS

protocol

converter

Connect directly

existing devices

to 350V DC

30kW

LED 10kW ventilation

2500W

230V

AC15x

Current

router 16A

6x

Office buildings v2

DE

SK

sup

po

rt

DE

SK

sup

port

LED

700VDC

700V

48V

LED

700VDC

700V

48V

700V

48V

USB

-C1

00

W

USB

-C1

00

W

USB

-C1

00

W

Oth

er

de

sk

FLOOR

ROOF LED

700V

48V

LED

USB

-C1

00

W

USB

-C1

00

W

USB

-C1

00

W

CR 16A

CR 16A

CR 16A

CR 16A

500W 500W

500W500W

SELVSafe Extra Low Voltage

DC Zone 4a

Oth

er

de

sk

Opto to ethernet

Opto to ethernet

Fibre

CR 16A

COS interface

700VDC

3x400VAC

6kW 3x400V/50HZ

HB 100A

COS interface

700VDC

3x400VAC

25kW 3x400V/50HZ

1

3

1

3

HB 100A

700V

PV Strings

9kW700V

PV Strings

9kW

DC SYSTEMS

Direct Current BVR&D

© 2018 Harry Stokman

High Energy Label

Ambition A+

AFAS Floor

Existing AC devices

Existing AC devices

To Main DC Link

DC powered Vacuum cleaner robot

700V

PID Hot water

9kW

Hot water tapCongestion controlled

700V

Battery

9kW

HB 100A

Emergency Mode

UPS Mode

Peak shave & Comfort Mode

70..90%

30..70%

0..30%

• Simple cabling on roof

• Simple cabling on floor

• Dynamic UPS

• 3MW system LVDC based

• Reduction of labor

• Improved availability

• Modular system scalable

The project is not installed because of the timeline in the project.

Dynamic UPS

• 100% comfort at power outage until the battery level drops down below a threshold

• Slowly load discrimination depending on settings at the load side

• Different modes depending on building usage. Like weekend mode of event mode of office mode.

• Peak shaving

• In weekend possible to run different use cases

• Grid support

• Power limit a the grid side but possible to run higher energy levels in the building than the grid connection

PV

AFE

Time

VoltageState of Grid

760V

DC

DC

Emergency

Comfort Mode

Opportunity Mode

Load discrimination

700V

640V

500V

SOA

Power depending on SOC

80%90% 30% 40%

Battery

Power safe Mode

Happy hour Mode

Emergency Critical

Blackout

40%

Data and Power

PD

24V

USB-C

EthernetUSB

48V

24V

PD

24V

USB-C

EthernetUSB

PD

24V

USB-C

EthernetUSB

24VCONDesk

Protection

TCP/IPSwitch

Opto

RJ45

SOCKET

SOCKET

100W

250W

Congestion managed

Electrical adjustable desk

100W 100W

Ethernet/DP Ethernet/DP Ethernet

Desktop PC

Laptop Monitor Smartphone

DES

K

sup

po

rt

700V

48V

USB

-C1

00

W

USB

-C10

0W

USB

-C1

00

W

Oth

er d

esk

500W

Opto to ethernet

DC SYSTEMS

Direct Current BVR&D

© 2018 Harry Stokman

High Energy Label

Ambition A+

USB-C DESK

Desk Data & Power Hub

• 48V at desk

• Power management

• Single plug system

• Monitor and Laptops only one cable

• Ethernet and power

• Congestion management

DC Greenhous

• 1.5MW DC grow light blocks of 150kW @ 700V DC (tested for 1 year)

• Next step 1 MW HPS integration directly to the 700V DC grid

• In progress with the grid operator grounding issues and at some point move the DC connection to the grid operator (Alliander)

• Connect other greenhouses an share grid connections

• 700KW PV installation connected to the main AC/DC station

Manny hordes to take and taken

• Grounding AC and DC

• Converter station grid operator ready

• Limited budget for realization

• Hybrid breakers and Solid-state breakers

• Grid codes

• Financial stability of the users

• Installers acceptance

Floriade proposal

± 350V

3

± 350V

3

© 2019 Harry Stokman

EAN EAN EAN EAN

EV-CCS Q2

EV-CCS Q2 EV-CCS Q2

DC

AC

DC

AC

1

DC

AC

1X16A 1X16A

- kW- kW- kW

3PH 10kV MVAC

3PH 400V LVAC

+700V LVDC

DC Hybrid configuration

• AC connection to the houses 3.5kW• DC connection congestion managed +/-3kW• AC Support from DC link• Public services on DC• EV charging on DC grid• PV in the public space

SMART CITYDC is powering smart cities infrastructure DC Public service BUS

Fiber opticsPower Line Communication

Local municipality storage and AC grid

support

DC

DC

DC

DC

• DC outdoor public services

• AC grid support

• Increase power during the event solving the energy vs power issues in grids

• Reduce grid investment for the next 60 years

The Why (voltage level) in Current/OSIsolation is cheaper than conductors

Why 700V DC (640 … 760V range)

• Isolation windings in motors is in the safe range

• Clear number not confused by AC

• ± 60VDC droop

• Multiple grounding possible

• Similar design criteria's as 480V AC

• Lifetime improvement with 1200V semiconductors and capacitors

• In case for bipolar ±700V DC the 1400V DC levels is below the 1500V DC border this enable full range of the voltage band to use

Why 350V DC (320V…380V range)

▪ With ± 30VDC Droop the limit for direct touch disconnect time = 2.5 millisecond. So can be used in Home applications. In line with the IEC60479-2

▪ Clear number not confused by AC voltage levels in hybrid cases

▪ Multiple grounding possible

▪ Similar design criteria's as 230V AC

▪ Lifetime improvement with 600/650V semiconductors

▪ In case for bipolar ±350V DC the 700V DC levels is available for larger power devices

±350V DC use this for locations where direct touch protection is needed.

Standardized in the Netherlands in the TC64 application paper in the Dutch NEN1010 practical guide

DC Current Router (protection)16A (100A version in Q4-2018)

▪ 16A Solid-state Breaker <8us short detection

▪ RCD 1 80mA 0.1sec for 80..500mA <0.025sec (IEC 60479-2)

▪ G3 powerline communication for parametering

▪ RS485 SCADA control (MODBUS)

▪ kWh meter

▪ Guarantee selective

▪ Congestion management

▪ Priority structure

▪ No inrush current

▪ Black start protocol

▪ Protection of the incoming DC

▪ Arc detection

▪ <12W losses @16A / 350/700Vdc housekeeping and communication

▪ DC Zone 3 and 4 operation

4

DC and Direct Touch

• Additional protection (protection against direct contact) still possible for 350 VDC nominal 20 80V including droop with a overshoot to 400 VDC.

• Pictures below according to NEN NPR 9090 Wiring regulations in the Netherlands

Safety is in our traditionThe first historical safety shoes ☺

DC grounding

TN-SCD

G

G

M

PE

SGND

L-

L+

MAIN SUPPORT

Potential blocking device

TN-SCDD

G

G

M

PE

SGND

L-

L+

MAIN SUPPORT

Potential blocking devicePotential blocking device

G

G

(optional) in case of bipolar systems

G

G

(optional) in case of bipolar systems

TN-SCD

G

G

HOOFD

AARDE

TN-SCDD

G

G

M

PE

L-

L+

G

G

(Optie) voor bipolaire systemen

G

G

M

PE

L-

L+

HULP

AARDE

HOOFD

AARDEHULP

AARDE

(Optie) voor bipolaire systemen

• IT grounding possible but for small applications not for systems.

• TT Corrosion issues

• TN-C Corrosion issues

• TN-S Usable in single source systems but microgrids need addition protection measures to take