• Zhejiang Zhilu Transmission and Distribution Equipment Co., Ltd

Optimal Configuration Scheme for Photovoltaic Dedicated Prefabricated Substations in Industrial Parks

1. Introduction

2. Key Considerations for Industrial Park PV Substations

2.1 Load Characteristics

• High - Power Demand: Industrial parks typically have large - scale, three - phase loads with high peak demands.

• Variable Load Profiles: Fluctuations in manufacturing processes (e.g., shift work, machinery startups) require substations to handle dynamic load changes.

• Power Quality Requirements: Sensitive industrial equipment (e.g., automation systems, precision machinery) demands stable voltage and low harmonic distortion.

2.2 Spatial and Environmental Constraints

• Limited Footprint: Industrial areas often prioritize land use for production facilities, necessitating compact substation designs.

• Harsh Environments: Exposure to dust, chemicals, and vibrations in industrial settings requires robust, weather - resistant enclosures (e.g., IP65 rating).

2.3 Grid Connection Requirements

• Voltage Level Compatibility: Matching substation output voltage (e.g., 10kV/35kV) to the industrial park's internal grid or utility connection.

• Power Factor Correction: Industrial loads with low power factors (e.g., induction motors) require integrated compensation devices.

• Islanding Protection: Compliance with grid codes (e.g., IEEE 1547) to prevent unsafe islanding during grid outages.

3. Optimization Strategies

3.1 Capacity Matching

• Load Forecasting: Analyze historical industrial load data to determine the optimal PV capacity and substation size. For example:

• A 5MW industrial park with 60% average load factor may require a 3 - 4MW PV system and a correspondingly sized substation.

• Diversity Factor Consideration: Account for load diversity among different industrial facilities to avoid oversized substations.

3.2 Layout Design

• Modular and Compact Structures:

• Use prefabricated, modular substations with standardized components (e.g., 19 - inch rack - mount equipment) to minimize footprint.

• Opt for vertical stacking of high - voltage and low - voltage sections to reduce floor space.

• Hot - Swap Capability: Design for quick replacement of critical components (e.g., transformers, inverters) to minimize downtime during maintenance.

3.3 Integration of Energy Storage

• Battery Energy Storage Systems (BESS):

• Install BESS within the substation to store excess PV energy during low - demand periods and discharge during peak hours, reducing grid reliance.

• Size the BESS based on load shifting requirements (e.g., 2 - 4 hours of storage capacity).

• Peak Shaving Control: Use intelligent energy management systems to prioritize BESS discharge during high - tariff periods, optimizing cost savings.

3.4 Power Quality Enhancement

• Active Harmonic Filters (AHF):

• Integrate AHFs to mitigate harmonics generated by non - linear industrial loads (e.g., variable - frequency drives).

• Design AHF capacity to meet IEEE 519 harmonic limits (e.g., THD <5%).

• Reactive Power Compensation:

• Deploy static var generators (SVG) or capacitor banks to maintain a power factor ≥0.95, reducing penalties and improving grid stability.

3.5 Smart Monitoring and Control

• IoT - Enabled Sensors:

• Install sensors for real - time monitoring of temperature, humidity, vibration, and electrical parameters (voltage, current, power).

• Use edge computing to analyze data locally and trigger alerts for 异常 conditions (e.g., overheating, insulation degradation).

• Remote Management:

• Enable remote access via SCADA or cloud - based platforms for centralized control, fault diagnosis, and predictive maintenance.

4. Configuration Design

4.1 Electrical System

• High - Voltage Side:

• Select 10kV/35kV vacuum circuit breakers with short - circuit breaking capacity ≥25kA to handle industrial fault currents.

• Include voltage transformers (VT) and current transformers (CT) for metering and protection.

• Transformer:

• Choose dry - type transformers (e.g., epoxy - encapsulated) for fire safety in industrial environments.

• Size the transformer with a 20 - 30% overload capacity to accommodate peak loads.

• Low - Voltage Side:

• Configure modular switchboards with main circuit breakers rated for high - current industrial loads (e.g., 2000A–4000A).

• Integrate AHF and SVG units at the low - voltage busbars for centralized power quality management.

4.2 Physical Structure

• Enclosure Design:

• Use corrosion - resistant steel or aluminum enclosures with IP65 rating to withstand industrial environments.

• Incorporate forced ventilation and cooling systems to maintain internal temperatures <40°C under full load.

• Accessibility:

• Design double - door access for easy maintenance of high - voltage and low - voltage sections.

• Ensure clear working space (≥1.5m in front of equipment) and cable routing channels.

5. Case Study: 10MW Industrial Park PV Substation

• Load Profile: A mixed - use industrial park with manufacturing, logistics, and office facilities, averaging 6MW of demand with 8MW peak.

• Configuration:

• Transformer: Two 5MVA, 10/0.4kV dry - type transformers (N + 1 redundancy).

• High - Voltage Section: 10kV ring main unit (RMU) with vacuum circuit breakers.

• Low - Voltage Section: 4000A main switchboard with integrated 1MVar SVG and 500A AHF.

• BESS: 2MWh lithium - ion battery for peak shaving and grid support.

• PV System: 10MW DC capacity (8MW AC after derating).

• Substation:

• Expected Benefits:

• 30% reduction in peak grid demand.

• Power factor improvement from 0.85 to 0.98.

• 15 - year lifecycle cost savings of $1.2 million compared to non - optimized configurations.

6. Conclusion