In this article, we will analyze the operation and diagnosis of the rectifier bridge, also known as the diode bridge, in the electronic board of an inverter air conditioner.
1. Characteristics of the Inverter Compressor
The inverter compressor we will explore operates as a three-phase compressor, known for its high efficiency and consistency compared to single-phase compressors.
2. Current Transformation
Although the compressor works with three-phase current, the electricity supplied by the power company is single-phase alternating current. To convert this single-phase current into three-phase current, the electronic board located in the outdoor or condenser unit of the equipment is used.
3. Conversion Process
The conversion process is carried out in two stages:
- First Stage: The electronic board converts the single-phase alternating current into direct current.
- Second Stage: It then transforms this direct current into three-phase alternating current.
4. Differences Between Alternating Current and Direct Current
- Alternating Current (AC): Electrons change direction at regular intervals.
- Direct Current (DC): Electrons flow in a single direction with a constant voltage.
5. The Role of the Rectifier Bridge
The electronic board uses a diode bridge to convert alternating current into direct current. This bridge:
- Directs the positive and negative polarities of the alternating current to the same outputs, generating a uniform direct current.
- Consists of four diodes connected in series, each allowing current flow only when correctly polarized.
6. Operation of the Diode Bridge
To better understand its operation, consider an AC power outlet:
- When the polarity is positive, some diodes in the bridge allow current to flow in a specific direction.
- When the polarity is negative, other diodes in the bridge activate, ensuring that the current flow is always in the same direction toward the output.
7. Diagnosis and Testing of the Rectifier Bridge
Diode Testing
To check their condition, measure the voltage drop across the diode when it is forward-biased. A diode in this condition acts as a closed switch, allowing current flow.
Presence of the Rectifier Bridge
The rectifier bridge can be integrated into the electronic board or presented as discrete components.
8. Possible Faults
The rectifier bridge may fail due to:
- Electrical overloads.
- Damaged components, such as diodes that do not conduct current in any direction.
