Product introduction

By taking the self-healing type low voltage power capacitor as the main body and the intelligent measuring and controlling processor as the control center, the HY series intelligent combination type low voltage power capacitor (hereinafter referred to as combination capacitor) adopts microelectronic software and hardware technologies to realize zero-crossing control of thyristor, achieve time delay switching of contact of the mechanical type magnetic latching relay and accomplish zero-crossing switching technology of the low voltage power capacitor by mechanical type magnetic latching relay and thyristor combination switch circuit, and thus, power factor compensation is carried out in 0.4KV low voltage line. The product integrates sensing technology, network technology and the latest independent research and development results of electric technology to make the combination intelligent, small-sized and networked. Compared with traditional low voltage reactive compensation products, it has such features as automatically cycled switching; three-phase compensation, split-phase compensation, mixed compensation, optimized grading compensation, mixed optimized grading compensation; protection for over-current / over-voltage / under-voltage / under-current, voltage loss, phase loss, harmonic wave and temperature; and other functions such as measurement, control, communication and etc.

With the breakthrough in the structure of the existing low voltage reactive compensation devices, the product can realize a new mode of dispersed control and centralized management. The compensation system is featured by few parts, low temperature rise, small volume, low power consumption, harmonic resistance; simple structure, easy realization of standardization and normalization, flexible capacity configuration, good safety and reliability, cost saving, convenient use and etc. In addition, the capacitor to be switched can be forecast so that active power in power distribution and transformation is enhanced, investment in increasing the capacity is reduced and loss of compensation system is lowered. The real-time switching with dispersed control enhances stability of the compensation system and the zero-crossing control reduces impact of surge current onto the system voltage, so the product plays an important role in stabilizing system power network, reducing equipment loss, prolonging service life of the capacitor, as well as saving the energy and protecting the environment.

The product is widely used in the electric systems of low voltage inductive load, such as urban power network, rural power network, civil construction, factories, mines and other enterprises, petrochemical industry, electrified railway, rail traffic and other fields, acting as a reactive compensation device of low voltage power distribution networks. It has prominent effects in enhancing power factor, reducing line loss, stabilizing power network voltage, ensuring power supply quality, saving energy, lowering loss and improving efficiency, so that the new generation low voltage reactive compensation device is featured by good compensation effect, smaller volume, more cost saving, more flexible use, more convenient maintenance and higher reliability, meeting higher requirements of modern power networks to reactive compensation.

Common product models and specifications

Comparison of performance between our product and common products

Comparison of application between our product and common products

Main features of the product

Zero-crossing control: With switching-on in case of voltage zero crossing, switching-off in case of current zero crossing and no switching surge current, it can reduce voltage and current impacts onto equipment and prolong service life of equipment and capacitor.

Split-phase compensation: Independent compensation onto each of the three phases can be realized to solve the unbalanced load of the three phases. Compensation can be made on the phase of higher reactive shortage so as to realize the optimized compensation effect.

Three-phase joint compensation: The three phases are switched together and reactive compensation is made on the three-phase inductive load circuit so as to enhance power factor of three-phase power networks.

Optimized compensation: Switching can be controlled according to different compensation capacities. Optimized compensation can be made on three-phase or split-phase unbalanced power networks to enhance power factor to the utmost extent.

Mixed compensation: Three-phase joint compensation and split-phase compensation are carried out together in power networks to effectively control the balance of three phases in the system, greatly enhance compensation efficiency of the system, precisely control power factor of the system and avoid the occurrence of such problems as over-compensation, under-compensation and unbalanced three phases.

Protection for over-voltage, under-voltage, over-current, under-current: In case over-voltage or under-voltage occurs in the capacitor, the capacitor can be instantly switched off. When over-current is caused due to reduction of internal insulation of the capacitor, alarm signal will be sent and the capacitor will be immediately switched off.

Temperature protection: The temperature sensor is put at the center of internal parts of the self-healing type low voltage power capacitor to reflect internal heating caused by over-current, over-harmonic, too high leakage current and ambient temperature in a more accurate manner, so as to realize over-temperature protection. When the set temperature is exceeded, the capacitor will be automatically switched off and exit from the operation to reach the purpose of protecting the equipment.

Intelligent network: When multiple capacitors are networked for use, a network will be automatically generated. Among them, the one with the minimum address code is the host machine and the others are subsidiary machines, which compose a low voltage reactive power automatic control system.. If a subsidiary machine fails, it will exit automatically without influencing the work of the other machines. If the host machine fails, it will exit automatically and a new host machine will be produced from the other subsidiary machines to compose a new system and continue the operation.

Environment friendly: The capacitor is made of the special self-healing type dry capacitor which is environment friendly with integral flame retardant and explosion-proof performance and without leakage. Its attenuation rate is less than 1% per year.

High reliability: It needs no controller and adopts the mode of dispersed control, which can avoid collapse of the whole system caused due to controller failure. The electronic relay is switched on only when there is no failure, which has thoroughly solved the problem of frequent damage occurring in traditional non-contact relay, contactor, solid relay and electromechanical combination switch.

Combination structure: The product is standardized and networked, and the traditional controller, knife switch, combination switch, fuse, AC contactor, thyristor, thermal relay, capacitor are replaced to form the product into a whole. With little heating quantity, the device adopts combination type when it is installed. When the capacitor is damaged, there is no need to change the whole, just the single body needs replacement, which is simple and rapid. Therefore, the subsequent maintenance cost is saved.

Simple wiring: When multiple capacitors are installed, the run hours are 80% less than that of traditional mode, and 80% of connection wires and 80% of joints are reduced. With simple cabinet, rapid assembly can be realized on the service field and the production efficiency of whole-set equipment factories is greatly improved.

Convenient capacity expansion: The product is featured by small volume and simple wiring. With the increasing power load of electricity users, the capacitor quantity can be increased at any time. It changes the invariable limitations caused by complex wiring in the conventional mode and meets the need of enterprise development. Investment by instalments is available.

Convenient human-machine interface: The digital tube is adopted to realize cycled display: split compensation displays UA, UB, UC, IA, IB, IC, joint compensation displays UAC, IB, power factor COS, internal temperature of capacitor core and other system parameters. Device alarm types, such as over-voltage, under-voltage, under-current, over-temperature, unbalanced three-phase and switching status of each phase of the capacitor. In addition, the intelligent combination type capacitor is also provided with self-diagnosis function. Failures such as network communication failure can be viewed on the digital tube, which helps tracing field failure. Various parameters can be modified and set through the control panel.

Field compensation: It can be directly introduced beside the load, such as motor, to carry out field compensation, and thus avoiding connection wires from the capacitor cabinet to the load. The use is very convenient.

Main functions of the product

Main technical indexes of the product

Enviromental conditions
Ambient temperature: -25～60℃;
Relative humidity: 30%～85%RH;
Altitude: ≤2000m

Power supply conditions
Rated voltage: 220V～450V;
Voltage deviation: ±5%;
Harmonic voltage: Sine wave, with total distortion rate less than or equal to 5%;
Harmonic current: The allowable harmonic current at the point of common coupling shall not exceed the value required in the standard BG/T14549-1993.
Work frequency: 50Hz;
Power consumption: <0.2W/1kvar

Electrical safety
Electrical clearance, creepage distance, insulation strength, safety protection, short circuit strength, as well as sample circuit protection and control circuit protection conform to the requirements of relevant clauses in the electric power industry standard of the People’s Republic of China DL/T842-2003 “Ordering Specification for Low-voltage Shunt Capacitor Installation”.

Measurement error
Voltage: ≤±0.2%;
Current: ≤±0.2%;
Power: ≤0.2%;
Power factor: ±0.01;
Temperature: ±1℃.

Protection error
Voltage: ≤0.5%;
Current: ≤0.5%;
Temperature: ±1℃;
Time: ±0.1s

Reactive compensation parameters
Reactive compensation error: ≤50% of the minimum capacitor capacity;
Capacitor switching interval: >10s, to be set between 10-180s;
Reactive capacity: 5kvar, 10kvar, 20kvar
networking ≤32 sets.

Reliability parameters
Control precision: 100%;
Allowable switching times: 1 million times;
Attenuation rate of running time of capacitor capacity: ≦1%/year;
Switching attenuation rate of capacitor capacity: ≦0.1%/10,000 times;
Annual failure rate: ≦0.1%