Tuhao PV inverter top configuration

1,DC Clapper contactors

 
This is called the DC Clapper contactors, only ABB companies have. And in the original process, using magnetic blow extinguishing system design, there are super-extinguishing capability, on-off current of 4000ADC, voltage up to 1500VDC, especially suitable for harsh conditions, still require products with high performance industrial applications, but the price particularly expensive, a 1000V1200A2 level contacts, the price is about 18,000.

It is capable of the most critical performance IGBT, bus capacitors and other devices, such as a short circuit in case of emergency, disconnect the DC side at high currents, protecting people, components, safety equipment.

2,  EC centrifugal cooling fan

 
This is called EC centrifugal cooling fan, EBM production company. There are three kinds of cooling fan, AC AC fans, AC DC fan, and fan speed EC. AC AC input, the internal fans with integrated converter, external access to a PWM signal can achieve stepless speed control module built-in intelligent maintenance-free brushless DC motor, comes with RS485 output interface, 0-10V sensor output interface, 4 -20mA speed switch output interface, output interface and alarm signal output from the main interface. The product has a high intelligence, high-energy, high efficiency, long life, low vibration, low noise, and other characteristics can work uninterrupted.

The greatest feature of this fan is the frequency control function, according to the characteristics of photovoltaic power generation system, it is not every day than the speed of the fan switch 30% less, so it consumes less power than the other 35% of the fan, a 500KW solar inverter, a year can save 500 kWh. Less than other fan speed 30%, plus high-quality bearing service life of the fan speed is not more than 2 times.

3, Concept drives, fiber optic transmission.


CT-Concept, Switzerland is the world's large, medium power IGT drive technology and market leader, after 20 years of business, gradually occupies more than 80% of the global market share. CT-Concept launched a series of superb IGBT drive, high-end technology, functional excellence, high quality, cost-effective ideal to meet customers' most demanding and meticulous. Especially SCALE series IGBT drive, using original SCALE ASIC chipset driver for the global market and establish the authority of the industry standard.

This driver board the biggest feature is the use of magnetic and optical isolation technology transfer program, the usual way of light isolated magnetic isolation and quarantine, isolation optocoupler isolation mode due to the relatively low voltage, there are aspects of the transmission delay, aging and reliability, etc. issue. The use of pulse transformer isolation methods (magnetic separation) can achieve relatively high isolation voltage, and high reliability transformers, transmission delay is small, can achieve higher switching frequency, and there is no problem of aging.

Using optical fiber transmission, you can completely avoid the signal generator to the electrical interference between the driver board.

4, laminated busbars and the perfect combination of DC link film capacitors


Powder coating type busbar using anti-aging, corrosion resistance, high-performance insulation powder, with a smooth and shiny appearance and excellent electrical properties. DC from custom capacitor and the IGBT is not more than 10mm.

By the partial discharge is caused by the air gap between the positive and negative, so to minimize the air gap, there are two methods: 1, the adhesion between the busbars and the insulating sheet closely as possible, leaving no air gaps between the two, busbars and insulation sheet to be very clean, can not have any dust and dirt.

Stray inductance generated voltage spikes, voltage spikes higher, the greater the damage to the IGBT, the greater the loss of the system. Commonly used methods to reduce the stray inductance has three: one is the distance between the positive and negative currents as short as possible, two positive and negative direction is current as possible down overlay, 3 is the distance between the capacitor to the IGBT as short as possible.

5, ClassH level Reactor


Magnetic material with a thickness of 0.23mm loss low gold-oriented silicon steel, silicon steel thinner, the less iron loss. Using very thin silicon steel, making high-frequency loss in the core losses to a minimum point.

Conductive material of high quality magnet wire of 0.05mm outsourcing double Nomex, the wire only has a very low resistivity, while its temperature levels also increased to 220C.

Insulation material used using Dupond (DuPont) Company quality aromatic type Nomex paper, pressed glass insulation sheet.