I. Current Status and Existing Problems
Currently, water supply companies have extensive networks of water pipelines laid underground across urban and rural areas. Real-time monitoring of pipeline operation data is essential for effective command and control of water production and distribution. As a result, numerous data monitoring stations must be established along the pipelines. However, stable and reliable power sources near these pipelines are rarely available. Even when power is accessible, laying dedicated power lines is costly, vulnerable to damage, and involves complex coordination with utility providers for electricity billing, creating significant management challenges.
Various types of pipeline monitoring devices have been developed, but most suffer from significant limitations. The two most common approaches are:
Low-power battery-powered monitoring devices: These require regular battery replacement. Due to power consumption constraints, data transmission frequency is typically limited to once per hour, which is insufficient for real-time operational guidance.
Solar-powered monitoring devices: These require large-capacity batteries that need periodic replacement, resulting in high initial investment and maintenance costs.
Therefore, there is a pressing need to develop a new type of water pipeline monitoring system that overcomes these limitations.
II. Introduction to the Wind-Solar Hybrid Power Supply System
A wind-solar hybrid system is an integrated power generation and application system. It combines solar panels and wind turbines (which convert AC to DC) to generate electricity, storing the energy in battery banks. When power is needed, an inverter converts the stored DC electricity from the batteries into AC electricity, delivering it via transmission lines to the load.
This system enables simultaneous power generation from both wind turbines and solar panel arrays. Early hybrid systems were simple combinations of wind turbines and photovoltaic (PV) modules, lacking detailed mathematical modeling. As they were primarily used for low-reliability applications, these early systems often had short service lives.
In recent years, as the application scope of hybrid systems has expanded and demands for reliability and cost-effectiveness have increased, several advanced software packages have been developed internationally to simulate the performance of wind, solar, and hybrid power systems. These tools can model different system configurations to determine optimal setups based on performance and power supply costs.
Currently, two main methods are used internationally for sizing hybrid systems:
Power Matching Method: Ensures that the combined output power of the PV array and wind turbine under varying solar radiation and wind speed conditions exceeds the load power. This method is primarily used for system optimization and control.
Energy Matching Method: Ensures that the total energy generated by the PV array and wind turbine over time meets or exceeds the energy consumed by the load under varying conditions. This method is primarily used for system power capacity design.
III. Components of the Wind-Solar Hybrid Power System
A wind-solar hybrid power system mainly consists of a wind turbine, solar photovoltaic (PV) panels, a controller, batteries, an inverter, and AC/DC loads. The system configuration diagram is shown in the attached figure. This system is a hybrid renewable energy solution that integrates multiple energy sources—wind, solar, and battery storage—along with intelligent control technology for optimized system operation.
A wind-solar hybrid power system consists of several key components:
Wind Turbine: Converts wind energy into mechanical energy, which is then converted into electrical energy by a generator. This electricity charges batteries via a controller and supplies loads through an inverter.
Solar PV Panels: Utilize photovoltaic effects to convert sunlight into electrical energy, charging batteries and powering loads through an inverter.
Inverter System: Comprises multiple inverters converting DC from battery banks into standard 220V AC, ensuring stable operation of AC load devices. It also features automatic voltage stabilization for improved power quality.
Control Unit: Adjusts battery states based on solar intensity, wind speed, and load changes. It manages direct power distribution to DC/AC loads and excess energy storage in batteries. During insufficient generation, it draws from batteries to maintain system continuity.
Battery Bank: Stores energy from both wind and solar sources, playing a critical role in energy regulation and balancing loads. It ensures continuous power supply during shortages.
Advantages of wind-solar hybrid systems include higher stability and reliability due to energy complementarity, reduced battery capacity requirements, and minimized reliance on backup generators, leading to better economic and social benefits.
Fully utilizes wind and solar resources without external power supply.
Offers day-night and seasonal complementarity, ensuring high system stability and cost-effectiveness.
Reduces maintenance work and costs significantly.
Provides independent power supply unaffected by natural disasters.
Operates safely at low voltages with simple maintenance.
This system comprises two major parts: field stations and monitoring centers. Field stations include:
Wind Turbines: Convert wind energy into electricity for battery storage and supply to control boxes.
Solar Panels: Transform solar energy into electricity for battery storage or direct use.
Controllers: Manage the system’s operation, ensuring optimal charge/discharge cycles and protecting against overcharging.
Batteries: Store excess energy generated by wind turbines and solar panels for use during shortages.
Wind Turbine Selection: Ensure smooth operation and aesthetic appeal, minimizing tower load.
Optimal Configuration Design: Tailor the system's capacity based on local natural resources to maximize efficiency.
Pole Strength Design: Ensure structural integrity considering wind turbine and solar panel sizes and installation heights.
Safety Concerns: Systems are designed to withstand severe weather conditions, preventing potential hazards.
Power Supply Reliability: Adequate storage solutions ensure consistent power supply despite variable weather conditions.
Cost Issues: Technological advancements have reduced costs, making these systems economically viable with lower operational and maintenance expenses compared to traditional systems.
This concise summary highlights the essential aspects of wind-solar hybrid systems for pipeline monitoring, addressing their composition, advantages, and common concerns.