Digital generator inverter controller production process

Digital generators are a new generator product area that has developed in recent years. The popularization of this product is mainly concentrated in small generator systems below 5 kilowatts.

Traditional generator products mainly use a low-speed engine to drive a power frequency output generator to work normally, directly outputting the required power. This type of system has a relatively large volume due to the low speed of the engine. At the same time, it is difficult to reduce the volume of the low-speed generator, making it difficult to miniaturize and portability the entire system.

In terms of the quality of the output power supply, since the voltage and frequency of the output power supply are proportional to the engine speed, the fluctuation of the system speed under different load conditions will directly affect the stability of the output power supply voltage and frequency. The waveform of the output power supply is directly affected by the generator. Generally, the TDH of the output waveform of this type of small-power generator is not very ideal.

The emergence of digital generator solutions has solved the above problems well.

Digital Generator Controller Product Description

The controller product combines advanced power inverter technology with control technology. The output waveform is a standard sine wave. The specific waveform is as follows:

The system power output uses software closed-loop control technology. Compared with conventional hardware control methods, this product has a higher utilization efficiency of the engine output power, so that the same engine system can have a higher system output utilization efficiency.

Compared with the traditional generator system, the output waveform of this control system in the full power output stage is a sine wave, and the output power quality is high and the stability is good.

This system has a high degree of freedom in the type of output power, and can output power of different frequencies and voltages according to the specific requirements of different customers. The current output power types are as follows:

A. 220V/50Hz standard sinusoidal voltage output;

B. 230V/50Hz standard sinusoidal voltage output;

C. 110V/60Hz standard sinusoidal voltage output;

D. 115V/60Hz standard sinusoidal voltage output.

In terms of system control, we use advanced dynamic intelligent applicable control solutions. Due to the particularity of the system part of this product, if the engine system, carburetor part, and throttle adjustment mechanical part have a certain degree of discreteness, the traditional system control solution cannot accurately and stably achieve effective adjustment of the system under variable load conditions, or even if effective adjustment is achieved, it cannot achieve dynamic energy-saving effects during the adjustment process. Our system uses a control solution with our own technical characteristics, thus achieving effective and accurate control of the system. At the same time, our control system has strong system adaptability.

In the development process of system control design, we use self-developed PC software to realize the development mode combining controller with PC monitoring and analysis.

We use the powerful monitoring and analysis capabilities of PC to realize dynamic monitoring and analysis of the system, so as to ensure that we can achieve high-quality development of system control in a short time.
Since all the core technologies of this product are developed by us independently and we have advanced development methods, we can ensure that we have a faster response speed and stronger adaptability in supporting different customers of this product. We guarantee that within our series of products, we can cooperate to complete the development of a full-function prototype within four weeks on the premise that the customer's system prototype is completed.

In terms of system adaptability, our controller system has a strong matching range.

Our controllers can adapt to the oil engine systems of high-speed power engines as well as medium and low-speed power engines.

In the actual system, we make corresponding adjustments to the corresponding control parameters of the controller, so as to achieve the matching capability of our controller for engine systems with different characteristics without making corresponding changes to the hardware.

In engine systems with different characteristics, our controllers can achieve the same high-quality system control capabilities and power output quality.

Our overall functions in terms of product functions, features and advantages are as follows:

1. Standard sinusoidal voltage output function;

2. Electronic throttle speed control function;

3. Power usage status management and monitoring function;

4. Complete system abnormality adjustment and protection processing functions;

5. System output indication, abnormal indication (LED display) function;

Our products are designed to use perfect software monitoring and processing as much as possible, and to use software design to replace hardware design as much as possible, so as to greatly improve the design reliability of the system. In the processing of output waveforms, we use a waveform generation method controlled by pure software, so as to have a better processing solution in terms of the reliability and flexibility of the output power supply. We use a direct inverter system dynamic compensation method, so that the system has a higher inverter efficiency, which greatly reduces the temperature rise of the controller system while improving the efficiency of engine output power utilization. Our unique power soft start function in the system power output stage ensures the impact current suppression capability of the whole system combined with our controller in the power output stage. At the same time, we have added our unique whole system flameout control function in the case of extreme abnormalities in the design of the controller. In the case of extreme abnormalities in the system, the engine is forced to shut down to ensure the safety of the whole system. At the same time, our controller system has a built-in temperature detection function. In the case of abnormal temperature inside the controller system, the control system can make appropriate processing, thereby ensuring the absolute safety of the whole system.

Brief Analysis on System Throttle Control

There are several aspects that make up the digital generator inverter controller. Among these aspects, inverter control and system throttle control are its core parts. Now I will introduce the throttle control part with some personal experience. Because it involves some specific technologies, it is inconvenient to talk more. I can only give a brief introduction and communicate with you.

The main purpose of throttle control is to effectively control the engine output power and DC voltage during the dynamic working process of the system. There should be more means to achieve throttle control during the dynamic working process of the system based on different ideas.

From the perspective of automatic control, the control characteristics of the throttle control model should be a hysteresis system. At the same time, due to the relative changes in the mechanical processing consistency and long-term working characteristics, the uncertainty of the hysteresis degree is caused, which ultimately increases the control difficulty of the system. In this system, a good throttle control solution should have the following characteristics:

1. Realize static stability control at different speeds;

2. To achieve effective and stable control of the sudden addition and removal of the maximum rated load during system operation;

3. Achieve stable control of variable load process;

4. Effective control of the system can still be achieved after certain changes in the system status (such as a decrease in engine output power, a slight blockage in the carburetor, etc.);

5. Realize fast and accurate throttle handling under abnormal conditions.

From the perspective of automatic control, we must conduct a specific analysis of the system before achieving effective control of a system. The first step is to analyze the input parameters and output parameters and determine the mutual cause-and-effect relationship. In this system, in order to achieve throttle control, we can use the following input quantities: system speed, DC voltage, output current, and output power. The change in speed leads to the change in DC voltage (assuming that the output power is constant), and the change in output power will lead to the change in system speed (assuming that the throttle is fixed). It can be seen that the change in load is the internal cause that causes the system to change greatly (of course, the output current is also the corresponding embodiment of the load size). Therefore, the best effect of achieving effective control of the system must take the load change of the system as an important parameter (of course, some other parameters are also indispensable). Whether you ultimately expect to stabilize a specified speed or a specified voltage, load change is a very important parameter.

Relative to the engine system, if we expect to dynamically stabilize the system speed, we take the system speed as a physical variable and the load as a physical variable, then we can think that the load is a variable that can change suddenly (relative to the system speed) and the system speed is a gradual variable. What is the benefit of this analysis? The benefit of this analysis is that in the process of system control, in order to achieve rapid and effective control of the system speed, we can use the load to perform relative system feedforward control.

Of course, in order to achieve effective control of a system, the details must also be done well, and the local functional design cannot be separated from the larger system framework. For example, a good system throttle control must also make some mutual coordination with the inverter part.

For specific products, such as the throttle control of the digital generator system, this product does not require high-precision control like the servo system and motion control system. In the design of this system, after the initial control accuracy is achieved, the focus should be on the adaptability and stability of the control design. (Please indicate the source for original reprints from Power Network)