Shape up power grids of tomorrow
C-EPRI Electric Power Engineering Co., Ltd.
南瑞集团中电普瑞电力工程有限公司
No 16
Nanzhong Rd
Changping District
Beijing 102200
P.R.China
For further information
Tel: +86-10-66601712
Fax: +86-10-66601700
Email: info@cepri.com.cn
www.cepri.com.cn
南瑞集团中电普瑞电力工程有限公司
C-EPRI
Company
profile
State-of-the-art HVDC solutions . . .
creating new possibilities and meeting
your future challenges.
C-EPRI Electric Power Engineering Co., Ltd. (C-EPRI) is a high-tech
enterprise wholly owned by NARI Group Corporation (NARI), a subsidiary of
State Grid Corporation of China (SGCC). C-EPRI is mainly involved in the
research, manufacturing and engineering related to Classic HVDC
(LCC-HVDC), HVDC Flexible (VSC-HVDC) as well as DC Grid technology.
We provide a wide range of HVDC-related products including converter
valves, DC yard equipment, along with control and protection systems. We
also provide world-class turnkey solutions tailored to your specific needs.
We are dedicated to making contributions to the increased challenges being
faced in the sustainable development of electricity networks.
1/2
C-EPRI
Services
provided
Turnkey
solutions
Supporting you with
complete one-stop service
Classic HVDC solutions for
Back-to-back connection
Undersea cable transmission
UHVDC overhead transmission
De-icing applications
UHVDC converter station
C-EPRI’s turnkey solutions for HVDC systems support you
throughout the whole project process — through network analysis, engineering design, product supply, installation and commissioning.
Our advanced simulation and modelling tools allow us to carry
out detailed studies of your systems to assist with system analysis, network design and complete solution optimisation.
HVDC Flexible solutions for
Using our world-class laboratories, we make sure that our products are fully tested before delivery to site, ensuring their proper
operation even in the most onerous conditions.
Renewable energy integration
Supply for offshore loads
In-feed to city centres
Multi-terminal interconnection
Our specialised team delivers comprehensive support throughout the entire lifetime of a project. Every detail is fully controlled
and high standards are guaranteed.
HVDC Flexible converter station
3/4
C-EPRI
HVDC and
UHVDC
Shaping up super
highways for power grids
HVDC transmission systems use direct current instead of alternating current
for the transmission of electricity. Conventional line commutated converter
(LCC) HVDC converters use high power thyristors for electricity conversion
from AC to DC and vice versa.
Typical applications include back-to-back interconnections of asynchronous
networks and overhead or submarine transmission of electricity over long
distances.
In applications where load centres are located far away from energy
resources, UHVDC transmission shows great superiority. Compared to a
conventional ±500kV HVDC scheme, a ±800kV UHVDC scheme can reduce
transmission losses of up to 60% and provide power capacities up to 8000MW
and even more, almost doubling that of a ±500kV scheme. UHVDC is
expected to play a major role in shaping bulk power highway for smart electricity grids.
When the transmitted power is increased above 10GW, higher rating UHVDC
systems will be required – either by increasing voltage level (e.g. 1100kV) or
at existing voltage ratings with higher current carrying capabilities (e.g.
6250A). Both solutions are available with C-EPRI.
5/6
C-EPRI
A5000
UHVDC
converter
valve
Key features
Catering to the booming market for UHVDC applications both in China and abroad, we developed an A5000
type LCC-UHVDC converter valve technology, which makes use of electrically triggered thyristor (ETT). It is
rated up to ±1100kV/6250A, while downwardly compatible with lower voltage applications. The A5000 type
valve has passed all the type tests conforming to IEC60700 standard, accredited by DNV KEMA. Since
2011, A5000 technology has been applied in 4 projects, all with well proven performance.
A5000 converter valve tower
A5000 valve in type test
High power density
High availability and reliability with multi-redundancy
Suitable for up to ±1100kV/6250A application
Suitable for high altitude (4000m)
Excellent seismic performance (0.3g typical)
A5000 valve module
7/8
C-EPRI
HVDC
Flexible
Deliver green power
Shape future grid
HVDC Flexible is a new HVDC transmission technology, based on a voltage source converter (VSC). It makes
use of insulated gate bipolar transistors (IGBTs) instead of thyristors for power conversion between AC and
DC. In comparison to Classic HVDC, the most outstanding features of HVDC Flexible are high controllability
and flexibility, which lead to a number of potential advantages and applications.
By switching the IGBTs of the voltage source converter in a defined manner, HVDC Flexible generates a
controlled output voltage, the magnitude and phase angle of which can be changed rapidly and flexibly. As a
result, HVDC Flexible allows for independent and fast control of active and reactive power.
These advantages mean that HVDC Flexible provides an effective solution for wind farm integration, in
particular for offshore wind farms with a transmission distance over 50-100km where an AC cable technology
is not feasible. HVDC Flexible can also eliminate the requirement for a synchronous compensator and can
minimise the footprint. The reactive power controllability of HVDC Flexible can also be used to adjust the AC
network voltage and therefore contribute to improved power quality.
In contrast to Classic HVDC, power reversal in HVDC Flexible does not involve a change of DC voltage polarity, but via a change of DC current direction. This function makes HVDC Flexible a very attractive solution for
multi-terminal systems.
Other benefits associated with HVDC Flexible include black start capability, firewall against disturbance, inherent STATCOM functionality, low environmental impact, etc. Due to its superior technical features, HVDC Flexible has a wide range of applications:
Renewable energy integration
Supply of offshore loads
In-feeds to city centres
Multi-terminal systems
Feeding into passive networks
Grid interconnection and power trading
9 / 10
M2000
HVDC
Flexible®
converter
valve
FLECON1000
Control &
Protection
System
An HVDC Flexible converter consists of three phase units; each one includes two converter arms, both
with an arm reactor. Depending on the power and voltage ratings, each converter arm could be formed
by a number of vertically-stacked valve modules; each module contains six identical sub-modules
connected in series.
Each sub-module contains two IGBTs as the switching elements and a DC storage capacitor. The
number of sub-modules is redundant to ensure the reliable operation of an HVDC Flexible system in case
of component failures.
The FLECON1000 Control & Protection System (FLECON1000-CP) contains all the functionality needed to
operate the converter station and to protect the HVDC equipment and AC yard equipment. It is applicable
to both Classic HVDC and HVDC Flexible. Hierarchical design is employed for both software and hardware
to achieve complex control and protection functions. Relative isolation is maintained between different
levels of the hierarchical structure, coupled with dual redundant design, providing heightened availability
and reliability.
Key features
Key features
Hierarchical control and segmented protection
Universal rack and modular design
Easily scalable design and easy maintenance
Distributed hardware and software structure
High availability and reliability with multiredundancy
Up to 1000MW/±320kV, using 3300V/1500A IGBT
Easily scalable with modular design
Superior inflammability conforming to UL94
Excellent seismic performance (0.2g typical)
Using environmental-friendly materials (halogen-free)
Easy assembly and maintenance
Analogue signal acquisition unit
M2000 sub-module
M2000 valve module
C-EPRI
M2000 valve tower
FLECON1000 control & protection system
11 / 12
C-EPRI
DC Grid
Equipment
HVDC
simulation
DC circuit breaker
DC circuit breaker is an essential component in materializing a DC grid, which will increase the robustness of
the system during DC faults. As a pioneer in DC circuit breaker research, C-EPRI started relevant research
activities as early as 2012, with type tests successfully finished at early 2015.
An advanced concept is proposed by combining mechanical switching based on ultra high-speed disconnect
switch and power electronics switching based on high-power IGBT full-bridge cascade assembly, which not
only avoids the high losses associated with a solid-sate breaker, but also overcomes the limit of switching
speed of a mechanical breaker. As the first of its kind in the world, C-EPRI’s 200kV/1kA DC circuit breaker
can interrupt 15kA fault current within 3 milliseconds, 100 times faster than the blink of a human eye.
DC-DC converter
Functionally, DC-DC converter in DC grid is similar to power transformer in AC grid; its main functions include
DC grid networking, galvanic isolation and flow control. C-EPRI started R&D of DC-DC converter in early
2013. Currently, the research has come to the prototype phase, with a rating of 10kV/20kV, 3MW; type tests
are planned to be finished by the end of 2015.
Digital/Analogue real-time simulation system
To ensure safe and reliable operation of HVDC Flexible systems, a digital/analogue real-time simulation system is developed to facilitate system analysis and parameter design. It can also verify the
steady state and transient operation of both Valve Base Controller (VBC), and station control and
protection systems.
AC/DC system simulation: can simulate and verify AC system with more than 300 buses,
and VSC-HVDC system with up to 6 terminals
Key equipment functional test: can simulate up to 6000 MMC sub-modules
HVDC Factory Acceptance Test (FAT)
Valve control system test platform
The platform can test and verify the function
and reliability of LCC-HVDC valve control
system including VBE and TTM (Thyristor
Triggering and Monitoring unit). Test items
include:
TTM full-function test
VBE full-function test
VBE EMC test
VBE and TTM long-term operation test
DC circuit breaker installation
13 / 14
C-EPRI
HVDC
Testing
Manufacture
system
Solid rock for
reliable products
Converter valve workshop
Ultra-clean environment, 10,000m2
High-efficient assembly line
Annual production capacity:
Converter valves for 3 UHVDC schemes and 2 HVDC Flexible schemes
Synthetic test facilities (80kV/7500A)
High power electronics laboratory
AC voltage test facilities (600kV/5A)
HVDC valve testing laboratory
With a strong research and development
team, we have built a world-class test
laboratory for high power electronic applications. This is the third such laboratory
in the world and the first in China capable
of performing all the type tests (both
dielectric and operational type tests) for
up to ±1100kV UHVDC valve and
±500kV HVDC Flexible valve.
Additionally, it has been accredited by
China National Accreditation Board for
Conformity Assessment (CNAS), with
type test reference for more than 10
HVDC projects, including 5 UHVDC
projects and 2 VSC-HVDC projects.
DC voltage test facilities
(±2400kV/300mA)
Valve test
equipment
(VTE)
Quality control
Sourcing control
Repetitive firing
test equipment
(RFTE)
Switching
impulse test
Production process control
Factory test
Factory inspection
On-site inspection
AC voltage test
Hydraulic test
Heat-run test
15 / 16
C-EPRI
17 / 18
Project
experience
Consistent commitment to
outstanding performance
1. Lingzhou-Shaoxing UHVDC project
7. Jinping-Sunan UHVDC project
Commissioning: 2015
±800kV/8000MW/1722km
World’s largest DC transmission project
Commissioning: 2012
±800kV/7200MW/2100km
8.Sino-Russia HVDC BtB project
2. Xiamen Island supply VSC-HVDC project
Commissioning: 2012
±125kV/750MW
Commissioning: 2015
±320kV/1000MW/10.7km (subsea cable)
World’s highest voltage and power ratings utilizing VSC-HVDC
1
2
3
Commissioning: 2014
±800kV/8000MW/2210km
World’s largest DC transmission project
12
11
10
6. Southern Hami-Zhengzhou UHVDC project
9
Commissioning: rescheduled
±320kV/1000MW/47.6km (subsea cable)
World’s highest voltage and power ratings utilizing VSC-HVDC
8
5. Dalian City in-feed VSC-HVDC project
7
Commissioning: 2014
±800kV/8000MW/1680km
World’s largest DC transmission project
9. Nanhui wind farm integration
VSC-HVDC project
Commissioning: 2011
±30kV/18MW/8.4km (land cable)
6
4. Xiluodu-Zhejiang UHVDC project
5
Commissioning: 2014
±200kV/1000MW/141km (subsea cable)
World’s first 5-terminal VSC-HVDC system
4
3. Zhoushan five-terminal VSC-HVDC project
feasibility study
10. Ningdong-Shandong HVDC project
Commissioning: 2011
±660kV/4000MW/1330km
World’s first ±660kV HVDC project
11. Three Gorges-Shanghai II HVDC project
Commissioning: 2011
±500kV/3000MW/1048km
12. Lingbao II HVDC BtB project
Commissioning: 2009
166.7kV/750MW
World’s first 4500A HVDC project