Description

Product Feature

This series low-voltage passive filter devices are composed of filter capacitors and filter reactors, designed according to the characteristics of the power grid system and harmonic loads. They are switched on and off using dedicated contactors or thyristor switches, and the controller can control the filter branches based on power factor. The series low-voltage passive filter devices utilize professional filter simulation software for optimized filter design, ensuring that the filter compensation effect meets user needs. This improves power supply voltage quality, reduces losses, increases the power factor, maintains a good power environment, and ensures the safe operation of power distribution and electrical equipment.

Application Areas

This series low-voltage passive filter is suitable for industrial applications such as rectification, variable frequency speed control, metallurgical electrolysis, and chemical electrolysis power electronic equipment; transportation applications such as electrified railways, subways, and trolleybuses; broadcasting, postal services, telecommunications, IT industries sensitive to harmonic interference; and applications with strict power quality requirements such as convention centers, commercial buildings, and hospitals.

Performance Characteristics

● The device mainly consists of compensating filter capacitors, filter reactors, circuit breakers, fuses, contactors (or thyristor switches), and control and protection units. Dedicated filter branches are set according to the main harmonics of the power grid, such as commonly used 3rd, 5th, 7th, and 11th order filter branches. The circuit is designed according to the target power factor.

● The controller has a transformer monitoring function with high sampling accuracy. It adopts a professional anti-harmonic design method, which can accurately analyze the content of each harmonic in severe harmonic environments, accurately measure the phase angle of voltage and current, and accurately calculate reactive power.

● The filter device is designed and simulated using advanced computer software, resulting in significant filtering effects. We can design solutions tailored to specific customer requirements, achieving optimal power factor compensation and harmonic filtering characteristics.

● After the filter is put into operation, power quality is significantly improved. It filters out harmonics, reduces voltage fluctuations and suppresses voltage flicker, improves voltage stability and quality, and increases the power factor to over 0.95, resulting in significant economic benefits.

● We employ a comprehensive control and protection system with complete protection functions, including overcurrent, instantaneous overcurrent protection, overvoltage protection, undervoltage protection, and unbalanced current protection, ensuring safe and reliable operation.

● For rapidly changing, impactful loads, we can use electronic switching to achieve dynamic, real-time filtering compensation. The number and capacity of filter branches vary depending on the user’s load characteristics.

● We can select from three-phase common compensation, three-phase separate compensation, or a combination of both, based on the characteristics of the three-phase balanced or unbalanced load. Our modular structure ensures neat and uniform assembly, facilitating replacement and maintenance.

Technical Parameters

● Rated Voltage: 400V, 660V, 750V, 1000V

● Rated Frequency: 50Hz

● Rated Compensation Capacity: Below 500KVar/cabinet

● Harmonic Filtering Rate: Up to 60%, fully meeting national standards

● Overvoltage Capacity: Allows long-term operation at 1.1 times the rated voltage at the power frequency

● Overcurrent Capacity: Can operate long-term when the overcurrent does not exceed 1.3 times its rated current

● Capacitor Wiring Method: Filter branch connected in “Y” or “△” configuration.

● Measurement Error: Voltage: ±0.5%, Current: ±1.0%, Reactive Power: ±1.0%

● Switching Method: Automatic switching based on power factor

● Switching Delay: Adjustable from 0 to 999 seconds.

Operating Environment

● Ambient Temperature: -5℃ to +40℃ Humidity: 0～50%

● Altitude: ≤2000m

● Environmental Requirements: Free from oily dust, corrosive, flammable, and explosive gases

Note: Customization is available for other special applications and environmental conditions.

Main Components Introduction

● Intelligent Control and Protection Unit: Based on digital signal processing technology, it performs reactive power calculation on collected parameters, intelligently optimizes switching schemes, and outputs switching control signals using coded switching or cyclic switching methods. It features fast response speed, strong real-time performance, and rapid compensation to improve the power factor and operational stability of the power distribution system. A large-screen LCD display shows various electrical parameters such as system voltage, current, power factor, harmonics, active power, and reactive power. Data transmission and remote monitoring are achieved via RS232/RS485 communication ports.

● Thyristor Switch: The thyristor switch uses high-performance thyristor elements to form a contactless electronic switch. It features fast response, low wear, no noise, and seamless connection of capacitor banks to the power grid. It smoothly and dynamically switches capacitor banks at constant voltage and zero current, achieving seamless, surge-free, and transient switching; overcoming the transient processes generated during capacitor switching in traditional reactive power compensation devices, and preventing capacitor overheating and swelling.

● Filtering Capacitors and Reactors Composed of filtering capacitors and reactors connected in series, and precisely calculated impedance matching, it avoids parallel resonance and filters harmonics. It effectively filters 3rd/5th/7th and higher harmonic currents. The filtering capacitors are self-healing, environmentally friendly, and flame-retardant power capacitors with discharge resistors, overvoltage, and overcurrent protection devices. The filtering reactors are specifically designed and subject to strict tolerance control, with an insulation class of H (185℃). It operates stably for a long time at 1.1 times the rated voltage and 1.3 times the rated current, exhibiting low noise, low temperature rise, good linearity, and long lifespan. It also limits inrush current and operational overvoltage, extends the lifespan of power capacitors, and ensures the safe operation of electrical equipment.