Charging machines, as a type of electrical equipment, are not widely recognized and can be used to charge any device that needs to be charged. Different customers have different requirements for chargers. We usually divide chargers into high-frequency chargers and power frequency chargers based on frequency.
Differences and Similarities between High Frequency Chargers and Power Frequency Chargers
As the name suggests, high frequency refers to a high frequency that can reach over megahertz. Power frequency refers to low and medium frequency, generally 50HZ in China and 60Hz in foreign countries. High frequency chargers are generally lighter in weight and slightly cheaper in price compared to power frequency chargers of the same model. They do not come with transformers and charge the battery faster. The power frequency charger is relatively heavy in weight and comes with a transformer, which makes the cost slightly higher and the price more expensive. It takes 8-10 hours to fully charge the battery, resulting in a slower charging speed.
Although high-frequency chargers have fast charging speeds, they come at the cost of damaging the internal chemical composition of the battery, which can shorten its lifespan. Power frequency chargers cause minimal damage to batteries and can effectively extend their lifespan. For example, a battery with a lifespan of 3 years can only be used for over 1 year with high-frequency charging, while it can be used for over 2 years with power frequency charging.
Both high frequency and power frequency have advantages and disadvantages. For example, when charging electric vehicles, sometimes fast charging is required, and a high-frequency charger is needed. If there is no time requirement, power frequency is used. In some special occasions where frequency requirements are strict, it is necessary to choose according to the needs.
The difference in working mode between power frequency and high-frequency forklift chargers
The power device of the power frequency forklift charger works in a linear state, which means that the power device is always working when it is used, resulting in low efficiency, usually between 50% -60%, but it is a good linear power supply. The working mode of a linear power supply requires a voltage regulator to convert it from high voltage to low voltage. Generally, transformers are used, but there are also other types like KX power supplies that output DC voltage through rectification. In this way, its volume is also large, bulky, inefficient, and generates a large amount of heat. It also has its advantages: small ripple, good adjustment rate, and low external interference. Suitable for use with analog circuits, various amplifiers, etc.
High frequency forklift charger, its power components work in a switch state (one on one off, one on one off, frequency is very fast, the general flat switch power supply frequency is 100-200KHz, module power supply frequency is 300-500kHz). In this way, its loss is small and its efficiency is high, which also requires the use of materials with high magnetic permeability for transformers. Theres a bit of ink on it, its transformer is just a small word, with an efficiency between 80% and 90%. It is said that the best VICOR module in the United States can reach up to 99%. Switching power supplies have high efficiency and small size, but compared to linear power supplies, their ripple and voltage current regulation are discounted.
Use of power supply
The commonly used power supplies are divided into two categories: linear power supplies using power frequency transformers (iron cores, 50Hz) and switching power supplies using high-frequency transformers (iron cores, several thousand Hz). The principle of a switching power supply is to first convert AC power at a frequency of 50Hz into high-frequency current, and then convert it into low-voltage DC power through a high-frequency transformer after rectification. Due to the fact that high-frequency transformers of the same power have much smaller volumes than power frequency transformers - the higher the frequency, the smaller the volume - they can be made with high power, small volume, and light weight, and are therefore widely used. Its voltage regulation is mainly achieved by controlling the oscillation frequency. Therefore, if the shielding of the switching power supply is not done well, it is easy to emit harmonic interference and lose its voltage regulation performance when used for charging, resulting in voltage fluctuations or frequency variations due to high-frequency interference. Meanwhile, if the protection circuit of the switching power supply is not done well, once a fault occurs, its voltage may suddenly rise significantly and burn out the battery. So yes, linear power sources should have some room for development.