1. Frequency phase signal sampling transformation and shaping circuit
The generator or power grid line voltage signal first absorbs the clutter signal in the voltage waveform through the resistance and capacitance filtering circuit, and then sends it to the photoelectric coupler to form a rectangular wave signal after photoelectric isolation. The signal is transformed into a square wave signal after being reversed and reshaped by a Schmidt trigger.
2. Frequency phase signal synthesis circuit
The frequency phase signal of the generator or power grid is changed into two rectangular wave signals after sampling and shaping circuit, one of which has been reversed, and the frequency phase signal synthesis circuit synthesizes the two signals together to output a voltage signal proportional to the phase difference between the two. The voltage signal is sent to the speed control circuit and the closing lead Angle regulating circuit respectively.
3. Speed control circuit
The speed control circuit of the automatic synchronizer is to control the electronic governor of the diesel engine according to the phase difference of the frequency of the two circuits, gradually reduce the difference between the two, and finally reach the phase consistency, which is composed of the differential and integral circuit of the operational amplifier, and can flexibly set and adjust the sensitivity and stability of the electronic governor.
4. Closing the lead Angle adjustment circuit
Different closing actuator components, such as automatic circuit breakers or AC contactors, their closing time (that is, from the closing coil to the main contact completely closed time) is not the same, in order to adapt to the different closing actuator components used by users and make it accurate closing, the design of the closing advance Angle adjustment circuit, the circuit can achieve 0 ~ 20° advance Angle adjustment, That is, the closing signal is sent out in advance from 0 to 20° phase Angle before the simultaneous closing, so that the closing time of the main contact of the closing actuator is consistent with the simultaneous closing time, and the impact on the generator is reduced. The circuit consists of four precise operational amplifiers.
5. Synchronous detection output circuit
The output circuit of synchronous detection is composed of detecting synchronous circuit and output relay. The output relay selects the DC5V coil relay, the synchronous detection circuit is composed of and gate 4093, and the closing signal can be accurately sent when all conditions are met.
6. Determination of power supply circuit
The power supply part is the basic part of the automatic synchronizer, it is responsible for providing working energy for each part of the circuit, and the whole automatic synchronizer can work stably and reliably has a great relationship, so its design is particularly critical. The external power supply of the module takes the starting battery of the diesel engine, in order to prevent the power supply ground and the positive electrode from being connected, a diode is inserted in the input loop, so that even if the wrong line is connected, it will not burn the internal circuit of the module. The voltage regulating power supply adopts a voltage regulating circuit composed of multiple voltage regulating tubes. It has the characteristics of simple circuit, low power consumption, stable output voltage and strong anti-interference ability. Therefore, the input voltage between 10 and 35 V can ensure that the output voltage of the regulator is stable at +10V, taking into account the application of 12 V and 24 V lead batteries for diesel engines. In addition, the circuit belongs to linear voltage regulation, and the electromagnetic interference is very low.
Post time: Oct-23-2023