Generator set with adjustable gas flow

Abstract

The utility model discloses a generator set with adjustable gas flow. The generator set comprises a frequency conversion unit, a generator, an engine and an electromagnetic valve, wherein the engine is used for driving the generator to rotate to generate an alternating current signal; the electromagnetic valve is used for controlling the gas flow entering the engine; the electromagnetic valve is connected between an engine and a pressure reducing valve at a fuel gas source through a high-pressure gas pipe; and the frequency conversion unit is connected between the electromagnetic valve and the generator through a signal line. The electromagnetic valve is adopted to replace a pressure maintaining valve, the flow of gas entering the engine is finally controlled, and the factors of gas flow control instability caused by low rotating speed and unstable rotating speed of the engine, external environment factors, manufacturing errors and the like can be effectively avoided; the on-off frequency of the control electromagnetic valve is directly controlled through the frequency conversion unit according to the alternating current signal output by the generator, the flow of gas entering the engine can be accurately controlled, and therefore the engine can be stabilized at the needed rotating speed.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of gas adjustment of generator set, specifically relates to a kind of generator set of gas flow adjustable. BACKGROUND

[0002] When the engine of conventional generator set uses LPG / NG as fuel, LPG / NG fuel needs to pass through pressure reducing valve to reduce pressure (convert high-pressure gas into low-pressure gas) and pressure stabilizing valve to stabilize flow (drive internal diaphragm vibration frequency and amplitude to realize control of gas flow into engine through negative pressure change caused by engine speed and throttle opening), finally control gas flow into engine combustion chamber. However, the above control method has the following disadvantages:

[0003] 1. When starting at low temperature or normal temperature, the starting speed is relatively low, usually between 300 rpm and 500 rpm. At this time, the negative pressure at the engine intake port is low, the amplitude and frequency of the diaphragm in the pressure stabilizing valve are small, and the LPG / NG flow pumped into the engine is very low, which ultimately affects the starting effect.

[0004] 2. The vibration frequency of the diaphragm in the pressure stabilizing valve is affected by manufacturing errors such as diaphragm thickness and weight, as well as external environmental factors such as environmental temperature, gas source pressure fluctuation, and engine speed fluctuation, and the positive pressure at the engine intake port during engine operation. The fluctuation of LPG / NG flow at the pressure stabilizing valve caused by the above factors ultimately affects the consistency of engine performance, and may cause adverse effects such as wandering, engine emission, explosion, and unstable emission.

[0005] 3. At idle speed (below 2000 rpm), the speed is too low, the negative pressure at the engine intake port is low, the diaphragm vibration is unstable, and the LPG / NG flow is ultimately affected, causing unstable speed, wandering, and engine stall.

[0006] 4. Since the control of LPG / NG flow is completely dependent on the negative pressure at the engine intake port, it cannot be precisely controlled for different speeds and different operating points, making emission matching difficult and consistency poor.

[0007] When electric injection engine uses LPG / NG as fuel, the control of fuel flow is usually through position sensor, intake pressure sensor, atmospheric pressure sensor, temperature sensor, etc. to collect engine operating data in real time, analyze the collected data through separate ECU, and finally control the number of steps of stepper motor to achieve the purpose of controlling LPG / NG flow. Due to the integration of numerous sensors, the cost is relatively high, and the maintenance difficulty is large.

[0008] Therefore, in the face of the problems of difficult starting, poor performance consistency, low speed instability, poor emission consistency when using LPG / NG as fuel for conventional engines, and high cost and difficult maintenance when using LPG / NG as fuel for electronic injection engines, a generator set with higher reliability and lower cost and adjustable gas flow is an urgent technical problem to be solved at present. Content of the utility model

[0009] The utility model aims at providing a generator set with adjustable gas flow to solve the problems of low reliability and high cost of gas flow adjustment of existing generator sets.

[0010] To solve the above technical problems, the utility model provides a generator set with adjustable gas flow, which comprises a frequency conversion unit, a generator, an engine for driving the generator to rotate to generate an alternating current signal, and an electromagnetic valve for controlling the gas flow entering the engine; the electromagnetic valve is connected between the engine and a pressure reducing valve at a gas source through a high-pressure gas pipe; and the frequency conversion unit is connected between the electromagnetic valve and the generator through a signal line.

[0011] Further, the frequency conversion unit comprises a frequency converter and a control circuit; the frequency converter is used for acquiring the alternating current signal output by the generator and then converting the alternating current signal into a first identifiable electric signal recognizable by the control circuit; and the control circuit is used for acquiring the first identifiable electric signal and then adjusting a first execution signal corresponding to the first identifiable electric signal according to the first identifiable electric signal.

[0012] Further, the system further comprises a starting signal monitoring module for detecting whether the engine is in a starting stage, the starting signal monitoring module is signal connected with the frequency conversion unit, when the starting signal monitoring module detects that the engine is in the starting stage, a trigger instruction is sent to the frequency conversion unit, the on-off frequency of the electromagnetic valve is controlled by the second execution signal output by the frequency conversion unit to control the gas flow entering the engine when the engine starts.

[0013] Further, the starting signal monitoring module is a top dead center monitoring unit, which judges whether the engine is in the starting stage according to whether the top dead center of the engine is monitored.

[0014] Further, the top dead center monitoring unit is a flip-flop.

[0015] Further, the control circuit is integrated in the interior of the frequency converter.

[0016] Further, the control circuit is arranged outside the frequency converter.

[0017] The utility model has the advantages of:

[0018] 1. By using a solenoid valve instead of a pressure regulator valve, the flow of gas entering the engine can be controlled, which can effectively avoid the instability of gas flow control caused by low engine speed, unstable speed, external environmental factors, manufacturing errors, etc. The frequency converter directly controls the on and off frequency of the solenoid valve according to the AC signal output by the generator, which can accurately control the flow of gas entering the engine, so that the engine can be stabilized at the required speed.

[0019] 2. By separately controlling the gas flow during the start-up phase, the problem of low gas flow in the engine combustion chamber during the start-up phase due to low start-up speed can be avoided, which would affect the start-up performance. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, use the same reference numerals to denote the same or similar parts. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a structural schematic diagram of one embodiment of the present invention.

[0022] The components include: 1. Generator; 2. Trigger; 3. Frequency converter; 4. External control circuit; 5. Internal control circuit; 6. Solenoid valve; 7. Engine. Detailed Implementation

[0023] like Figure 1 The generator set with adjustable gas flow shown includes a frequency converter, a generator 1, an engine 7 for driving the generator 1 to rotate and generate an AC signal, and a solenoid valve 6 for controlling the gas flow into the engine 7; the solenoid valve 6 is connected between the engine 7 and the pressure reducing valve at the gas source via a high-pressure gas pipe; the frequency converter is connected between the solenoid valve 6 and the generator 1 via a signal line.

[0024] This invention replaces the pressure regulator valve with a solenoid valve 6 to ultimately control the gas flow into the engine 7. This effectively avoids the instability in gas flow control caused by factors such as low engine speed, unstable engine speed, external environmental factors, and manufacturing errors. By directly controlling the on / off frequency of the solenoid valve 6 based on the AC signal output by the generator 1 through the frequency converter, the gas flow into the engine 7 can be precisely controlled, thereby enabling the engine 7 to stabilize at the required speed.

[0025] According to one embodiment of the present application, the frequency conversion unit comprises a frequency converter 3 and a control circuit; the frequency converter 3 is used to obtain the AC signal output by the generator 1, and then convert the AC signal into a first identifiable electrical signal recognizable by the control circuit; the control circuit is used to obtain the first identifiable electrical signal, and then adjust a first execution signal corresponding to the first identifiable electrical signal according to the first identifiable electrical signal. The AC signal output by the generator 1 is first converted into a DC signal (and the above-mentioned first identifiable electrical signal) by the frequency converter 3, and then the required first execution signal is provided by the control circuit according to the converted signal, so that efficient and high-performance frequency adjustment can be achieved. The control circuit can adopt an existing integrated circuit, which is used to provide a control signal loop for the main circuit of the electromagnetic valve, and mainly comprises: (1) an operation circuit, which compares and operates the external speed, torque and other instructions with the current and voltage signals of the detection circuit, and adjusts the output voltage and frequency of the inverter; (2) a voltage and current detection circuit, which detects the voltage and current and the like in isolation with the main circuit potential of the electromagnetic valve; (3) a driving circuit, which drives the main circuit device of the electromagnetic valve, and is isolated from the control circuit to make the main circuit device of the electromagnetic valve conductive and off.

[0026] According to one embodiment of the present application, the system further comprises a starting signal monitoring module for detecting whether the engine 7 is in a starting stage, the starting signal monitoring module is in signal connection with the frequency conversion unit, when the starting signal monitoring module detects that the engine 7 is in a starting stage, a trigger instruction is sent to the frequency conversion unit, the second execution signal is output by the frequency conversion unit to control the on-off frequency of the electromagnetic valve 6, so as to control the gas flow entering the engine 7 when the engine 7 starts. In this embodiment, the gas flow is adjusted by simultaneously considering the real-time speed data and the current load data, so that the on-off frequency of the electromagnetic valve 6 can be adjusted in time according to the signal change to adjust the gas flow, so as to achieve the purpose of timely response and accurate control.

[0027] According to one embodiment of the application, the start signal monitoring module is an upper dead center monitoring unit, which judges whether the engine 7 is in the start stage according to whether the upper dead center of the engine 7 is monitored. Generally, when the piston runs to the upper dead center, the ECU judges the best timing of ignition through the signal of the crankshaft position sensor and controls the energization of the high-voltage coil to make the spark plug produce an electric arc to ignite the mixture, the vehicle is successfully fired, the engine 77 is started, and the application judges whether the engine 7 is in the start stage by monitoring the upper dead center of the engine 7, which has a faster response speed, thereby ensuring the corresponding speed of the gas flow control in the start stage of the engine 7. When the engine 7 starts, the upper dead center monitoring unit monitors that the engine 7 is at the upper dead center, and sends a trigger signal to the frequency converter 3, and the frequency converter 3 outputs a second execution signal according to the trigger signal to control the on-off frequency of the electromagnetic valve 6, so as to control the gas flow into the engine combustion chamber when the engine 7 starts; and when the engine 7 is normally started, the electromagnetic valve 6 is controlled according to the alternating current signal output by the generator 11.

[0028] According to one embodiment of the application, the upper dead center monitoring unit is a flip-flop 2. The generator 1 rotor is installed on the engine 7, and the engine 7 drives the rotor of the generator 1 to rotate after the engine 7 is operated, which cuts the magnetic field of the outer ring of the rotor of the generator 1 to generate alternating current, so that the voltage signal change of the flip-flop 2 can judge whether the engine 7 reaches the upper dead center, thereby judging that the engine 7 starts, which has the characteristics of high sensitivity, high stability, and fast response speed.

[0029] According to one embodiment of the application, the control circuit is integrated in the inside of the frequency converter 3, that is, the built-in control circuit 5. The system has relatively few parts, the control circuit is simple, and by integrating the control circuit in the frequency converter 3, the control system structure is more simple, which is convenient for installation and maintenance.

[0030] According to one embodiment of the application, the control circuit is arranged outside the frequency converter 3, that is, the external control circuit 4. Arranging the control circuit outside the frequency converter 3 can facilitate maintenance or replacement of the control block.

[0031] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the application and are not limited. Although the application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions of the application, which should be covered in the scope of the claims of the application.

Claims

1. A gas flow adjustable generator set, characterized by, The frequency conversion unit, the generator, the engine for driving the generator to rotate to generate an alternating current signal, and the electromagnetic valve for controlling the flow of gas into the engine; the electromagnetic valve is connected between the engine and the pressure reducing valve at the gas source through a high-pressure gas pipe; the frequency conversion unit is connected between the electromagnetic valve and the generator through a signal line.

2. The gas flow adjustable genset of claim 1, wherein, The frequency conversion unit includes a frequency converter and a control circuit; the frequency converter is used to obtain the alternating current signal output by the generator, and then convert the alternating current signal into a first identifiable electric signal recognizable by the control circuit; the control circuit is used to obtain the first identifiable electric signal, and then adjust a first execution signal corresponding to the first identifiable electric signal according to the first identifiable electric signal.

3. The gas flow adjustable generator set according to claim 1 or 2, characterized in that, It also includes a start signal monitoring module for detecting whether the engine is in the starting stage, the start signal monitoring module is signal connected with the frequency conversion unit, when the start signal monitoring module detects that the engine is in the starting stage, it sends a trigger instruction to the frequency conversion unit, and controls the on-off frequency of the electromagnetic valve through the second execution signal output by the frequency conversion unit to control the flow of gas into the engine when the engine starts.

4. The gas flow adjustable genset of claim 3, wherein, The start signal monitoring module is a top dead center monitoring unit, which judges whether the engine is in the starting stage according to whether the top dead center of the engine is monitored.

5. The gas flow adjustable genset of claim 4, wherein, The top dead center monitoring unit is a flip-flop.

6. The gas flow adjustable genset of claim 2, wherein, The control circuit is integrated in the interior of the frequency converter.

7. The gas-flow-adjustable genset of claim 2, wherein, The control circuit is arranged outside the frequency converter.

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