HVDC Converter Valve Insulation Segmentation

Solution Overview

Problem

High Voltage Direct Current (HVDC) power transmission systems face challenges with insulation at increasingly higher voltage levels, leading to bulkier equipment and increased development costs due to the need for specialized insulation designs.

Innovation Solution

A substation design featuring series-connected converter valve elements with multiple potential levels, where the second set of converter valve elements is housed in casings on elongated post-like insulation, allowing existing insulation to be adapted for higher potentials without requiring new insulation designs for the highest voltage level.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If insulation is designed for very high voltage levels (1000 kV or above), then the insulation can handle the required voltage levels, but the equipment becomes bulkier and development costs increase

Engineering Contradiction:

Improveinsulation capabilityVSAvoidequipment bulkiness

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The converter valve elements are divided into two distinct sets: a first set operating between first and second potentials, and a second set operating between second and third potentials. The second set is housed in casings placed on elongated post-like insulation with the casing potential positioned between the second and third potentials. This segmentation allows each insulation system to be designed for lower voltage differences rather than the full high voltage, reducing equipment bulkiness while maintaining the ability to handle very high voltage levels.

Inventive Principle:

Principle #1Segmentation

2Reliability

If insulation is designed for very high voltage levels (1000 kV or above), then the insulation can handle the required voltage levels, but development costs increase

Engineering Contradiction:

Improveinsulation capabilityVSAvoiddevelopment costs

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The converter valve elements are divided into two distinct sets: a first set operating between first and second potentials, and a second set operating between second and third potentials. The second set is housed in casings placed on elongated post-like insulation with the casing potential positioned between the second and third potentials. This segmentation allows each insulation system to be designed for lower voltage differences rather than the full high voltage, reducing equipment bulkiness while maintaining the ability to handle very high voltage levels.

Inventive Principle:

Principle #1Segmentation

3Ease of manufacture

If existing equipment with insulation adapted for known potentials is used for new higher potentials, then development costs are reduced, but the insulation must be adapted to handle the voltage differences

Engineering Contradiction:

Improvedevelopment costsVSAvoidinsulation adaptation

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The converter valve elements are divided into two distinct sets: a first set operating between first and second potentials, and a second set operating between second and third potentials. The second set is housed in casings placed on elongated post-like insulation with the casing potential positioned between the second and third potentials. This segmentation allows each insulation system to be designed for lower voltage differences rather than the full high voltage, reducing equipment bulkiness while maintaining the ability to handle very high voltage levels.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS9093921B2Insulation in a power transmission system

Publication Date: 2015.07.28 HITACHI ENERGY LTD

AI summary

A substation has a converter comprising a first set (S1) of series connected converter valve elements provided between a first (V1) and a second (V2) potential, where the absolute value of the second potential is higher than the absolute value of the first potential, and a second set (S2) of converter valve elements, comprising at least one converter valve element, provided between the second and a third potential (V3), where the absolute value of the third potential is higher than the absolute value of the second potential and all converter valve elements of the second set are placed inside one or more casings (28) placed on elongated post-like insulation (24), where the potential of the end of the post-like insulation on which the casings are placed is in a range between the second and the third potential, while the other end of the post like insulation is at ground potential.