A control system and implementation method for improving the instantaneous power of a diesel generator

Abstract

The application discloses a control system and implementation method for improving instantaneous power of a diesel generator, comprising a super capacitor and a super capacitor, the super capacitor and the super capacitor are connected with an inverter through a relay normally closed contact, the inverter comprises four IGBT tubes; the control system further comprises a diesel generator, a voltage monitoring sensor, a power load, one end of the diesel generator is connected with a rectifier voltage stabilizer, the other end is connected with the ground, one end of two input ends of the voltage monitoring sensor is connected with the rectifier voltage stabilizer, the other end is connected with the ground, one end of an output end of the voltage monitoring sensor is connected with a relay coil, the other end of the relay coil is connected with the ground, one end of the power load is connected with the rectifier voltage stabilizer, and the other end is connected with the ground. The application has the following advantages: when instantaneous voltage reduction trend appears due to sudden increase of the power load, the super capacitor is used as a supplementary energy source, instantaneous output power of the diesel generator is improved, and stable voltage and frequency are quickly responded.

Description

Technical Field

[0001] This invention relates to a control system and implementation method for improving the instantaneous power of a diesel generator, belonging to the field of generator control technology. Background Technology

[0002] A diesel generator uses compression ignition to inject diesel fuel into the cylinder under high pressure for combustion, which pushes the piston to do work. The crankshaft of the diesel generator is coaxially connected to the synchronous AC generator. The rotating rotor cuts the magnetic field lines of the stator, generating an induced electromotive force according to Faraday's law of electromagnetic induction. Due to the residual magnetism of the magnetic pole core, the armature coil continuously cuts the magnetic field lines in the alternating magnetic field, forming a closed-loop current.

[0003] When the electrical load increases, the stator coil current of the diesel generator increases, which increases the resistance of the rotor cutting magnetic lines and slows down the rotation speed. If the power of the diesel generator is not increased, the output voltage and frequency of the diesel generator will decrease.

[0004] Diesel generators need to respond quickly to load changes, such as when there is a sudden increase in power demand, and must immediately increase power to maintain voltage and frequency stability.

[0005] Especially in situations requiring high reliability and rapid response, such as data centers, hospitals, or industrial power, the problem may be that the generator does not respond quickly enough when the load changes, leading to voltage fluctuations or even equipment shutdown.

[0006] To address the above issues, existing technologies employ air intake supercharging, which includes turbocharging and supercharging. The core principle of turbocharging is to recover energy from engine exhaust gases to drive a compressor, improving intake efficiency and thus enhancing power output. The core principle of supercharging is to use the engine crankshaft to drive a turbocharger, increasing air pressure in the intake manifold, thereby increasing engine intake volume and power output. ECU tuning adjusts the fuel-air mixture ratio and injection timing to increase the output power of the diesel generator M. Flywheel energy storage stores mechanical energy by driving a high-speed flywheel through the diesel generator M; when power is needed, the flywheel and diesel generator rotor are coupled, transferring the stored mechanical energy to the diesel generator. Electrical energy storage uses batteries to store electrical energy; when the electrical load increases, the batteries discharge to supplement the power shortage.

[0007] However, the above has the following drawbacks:

[0008] The intake turbocharging technology has a lag in response; it typically increases output power only after the diesel generator's M voltage drops by 2 seconds due to increased load.

[0009] ECU tuning, adjusting the fuel-air mixture ratio, and adjusting the timing angle can cause incomplete combustion of the fuel-air mixture, resulting in excessive exhaust emissions and engine overheating.

[0010] Flywheel energy storage requires complex mechanical structures and is costly. Moreover, due to the mechanical size limitations of diesel generators, the flywheel cannot be very large, resulting in limited storage of mechanical energy and thus limited power output.

[0011] The main problems with energy storage devices are voltage matching and phase consistency. The storage device needs to be charged by a diesel generator. Due to voltage drop in the rectifier, the rated voltage of the storage device is lower than that of the generator. When the inverter increases the output power of the diesel generator, the voltage loss in the inverter requires the rated voltage of the storage device to be higher than that of the generator. This creates a voltage discrepancy. If a transformer is used to solve the voltage difference, the transformer coil has high internal resistance and cannot provide instantaneous high current. To solve the instantaneous high current problem, a transformer with a very large wire diameter must be used, potentially making the transformer larger and heavier than the diesel generator itself. Furthermore, the diesel generator generates alternating current (AC), and the storage device also generates AC after inversion. The two AC currents are superimposed and need to be perfectly synchronized. Phase angle deviations can lead to overcurrent or even short circuits. In current technology, it is difficult to synchronize the phases of the inverter and generator, often resulting in phase angle differences. Summary of the Invention

[0012] The technical problem to be solved by the present invention is to provide a control system for improving the instantaneous power of a diesel generator in response to the above-mentioned shortcomings. When the voltage drops instantaneously due to a sudden increase in electrical load, a supercapacitor is used as a supplementary energy source to instantly increase the output power of the diesel generator, quickly respond to stable voltage and frequency, and solve the problem of lag. Through a voltage monitoring sensor, when the voltage drops instantaneously beyond the threshold due to a sudden increase in electrical load, the output power is increased by discharging the supercapacitor within 0.2 seconds, and the voltage is pulled up to the rated value.

[0013] The voltage matching and phase consistency issues are addressed through logic circuit conversion, enabling low-voltage charging and high-voltage discharging of the battery. By sampling the phase of the diesel generator's output voltage and generating a trigger signal by superimposing a sine wave and a triangular wave, the sampled phase is reproduced in the inverter, achieving the in-phase superposition of the diesel generator's output voltage and the battery's inverter AC power, thus avoiding overcurrent or even short circuit phenomena.

[0014] To solve the above technical problems, the present invention adopts the following technical solution:

[0015] A control system for improving the instantaneous power of a diesel generator includes supercapacitor SC1 and supercapacitor SC2. Supercapacitor SC1 and supercapacitor SC2 are connected to an inverter via normally closed contacts of a relay. The inverter includes four IGBT transistors.

[0016] The control system also includes a diesel generator M, one end of which is connected to a rectifier regulator TB and the other end is grounded. The control system also includes a voltage monitoring sensor Q, one of which is connected to the rectifier regulator TB and the other end is grounded. The output terminal of the voltage monitoring sensor Q is connected to one end of a relay coil KM-0 and the other end of the relay coil KM-0 is grounded. The control system also includes an electrical load W, one end of which is connected to the rectifier regulator TB and the other end is grounded.

[0017] Furthermore, the positive terminal of the supercapacitor SC1 is connected to one end of the normally open contact KM-1 and one end of the normally closed contact KM-6 of the relay; the negative terminal of the supercapacitor SC1 is connected to one end of the normally closed contact KM-5 and one end of the normally open contact KM-2 of the relay; the positive terminal of the supercapacitor SC2 is connected to one end of the normally open contact KM-3 and the other end of the normally closed contact KM-5 of the relay; the negative terminal of the supercapacitor SC2 is connected to one end of the normally open contact KM-4 and one end of the normally closed contact KM-7 of the relay; the other end of the normally open contact KM-1 and the other end of the normally open contact KM-3 are connected to a rectifier and voltage regulator TB; the other end of the normally open contact KM-2 and the other end of the normally open contact KM-4 are connected to a rectifier and voltage regulator TB.

[0018] Furthermore, an inverter is connected to the other end of the normally closed contact KM-6 and the other end of the normally closed contact KM-7 of the relay. The inverter includes IGBT transistors VT1, VT2, VT3, and VT4. The collectors of IGBT transistors VT1 and VT2 are connected to the other end of the normally closed contact KM-6 of the relay. The emitters of IGBT transistors VT3 and VT4 are connected to the normally closed contact KM-7 of the relay. A rectifier regulator TB is connected to the emitters of IGBT transistors VT1 and VT3. The emitters of IGBT transistors VT2 and VT4 are grounded.

[0019] The collector and emitter of IGBT VT1 are connected in parallel with diode D1, the collector and emitter of IGBT VT2 are connected in parallel with diode D2, the collector and emitter of IGBT VT3 are connected in parallel with diode D3, and the collector and emitter of IGBT VT4 are connected in parallel with diode D4.

[0020] Furthermore, the control system also includes a comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP5 is grounded. The inverting input of the comparator operational amplifier OP5 is connected to the output of the comparator operational amplifier OP4 and one end of a resistor R8. The other end of the resistor R8 is connected to the output of the comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP4 is connected to the inverting input of the comparator operational amplifier OP3, the output of the comparator operational amplifier OP2, one end of a resistor R1, and one end of a capacitor C1. The inverting input of the comparator operational amplifier OP4 is connected to one end of a diode D6. The non-inverting input of the comparator operational amplifier OP3 is connected to one end of a diode D5. The other ends of diode D5 and diode D6 are connected to one end of a resistor R6 and one end of a resistor R7. The other end of resistor R6 is connected to a voltage regulator, and the other end of resistor R7 is grounded.

[0021] Furthermore, the non-inverting input terminal of the comparator operational amplifier OP2 is connected to one end of resistor R5, and the other end of resistor R5 is grounded. The inverting input terminal of the comparator operational amplifier OP2 is connected to the other end of capacitor C1 and one end of resistor R4. The other end of resistor R4 is connected to one end of resistor R3 and one end of resistor R2. The other end of resistor R2 and the other end of resistor R1 are connected to the non-inverting input terminal of the comparator operational amplifier OP1. The other end of resistor R3 is connected to the output terminal of the comparator operational amplifier OP1, and the inverting input terminal of the comparator operational amplifier OP1 is grounded.

[0022] Furthermore, the gate of IGBT VT1, the gate of IGBT VT4, and the output terminal of comparator operational amplifier OP3 are voltage input terminals a, and the gates of IGBT VT2, IGBT VT3, and the output terminal of comparator operational amplifier OP5 are voltage input terminals b.

[0023] A method for implementing a control system to enhance the instantaneous power of a diesel generator includes the following steps:

[0024] Step 1: Supercapacitor stores electricity;

[0025] When the diesel generator M is in stable working condition, its rated output voltage is U0. The output of the voltage monitoring sensor Q causes the coil of relay KM-0 to be energized, and the normally open contacts of relays KM-1, KM-2, KM-3, and KM-4 are closed. Supercapacitors SC1 and SC2 are connected in parallel. The output voltage of the diesel generator M charges supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB. The charging voltage is U1. Because there is voltage loss in the rectifier circuit, U1 is less than the rated output voltage U0 of the diesel generator M.

[0026] Let the charging circuit voltage be Vu, the internal resistance be R, the supercapacitor voltage be Vt, and the total capacitance of the supercapacitor be C. According to the capacitor charging formula... After time t=R*C, the supercapacitor is fully charged;

[0027] Once the supercapacitor is fully charged, the rectifier regulator TB stops working.

[0028] Furthermore, the implementation method also includes the following steps:

[0029] Step 2, supercapacitor discharge;

[0030] The diesel generator M is equipped with a voltage monitoring sensor Q at its output terminal. When the electrical load suddenly increases, causing the diesel generator M to instantly decrease in speed, the voltage monitoring sensor Q detects that the output voltage has dropped to a threshold, and its output terminal stops outputting. The relay coil KM-0 is released, and the normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay are opened. Then, the normally closed contacts KM-5, KM-6, and KM-7 of the relay are closed, and the supercapacitors SC1 and SC2 are disconnected from the charging circuit, changing from parallel to series connection.

[0031] The inverter converts the DC power from the series connection of supercapacitors SC1 and SC2 into AC power. Each IGBT transistor has a diode connected in parallel between its collector and emitter. When the inverter load is an inductive load, the diode can eliminate the reverse induced electromotive force and protect the IGBT transistor from being damaged by the reverse induced electromotive force.

[0032] IGBT VT1 and IGBT VT4 form the inverter's forward output circuit, while IGBT VT2 and IGBT VT3 form the inverter's reverse output circuit. When the gates of IGBT VT1 and IGBT VT4 are connected to a forward voltage, and the gates of IGBT VT2 and IGBT VT3 are not connected to a forward voltage, IGBT VT1 and IGBT VT4 are turned on, while IGBT VT2 and IGBT VT3 are turned off, resulting in a forward output from the inverter. Current flows out from the positive terminal of supercapacitor SC1 and forms a circuit through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT1, the upper part of the electrical load W, the collector and emitter of IGBT VT4, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2.

[0033] When the gates of IGBT VT2 and IGBT VT3 are connected to a positive voltage, while the gates of IGBT VT1 and IGBT VT4 are not connected to a positive voltage, IGBT VT2 and IGBT VT3 are turned on, and IGBT VT1 and IGBT VT4 are turned off. The inverter outputs in reverse, and the current flows out from the positive terminal of supercapacitor SC1, forming a circuit through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT2, the lower part of the electrical load W, the collector and emitter of VT3, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2.

[0034] By alternately turning on the gates of IGBT VT1, IGBT VT4, IGBT VT2, and IGBT VT3, the DC-to-AC inverter process can be achieved.

[0035] Let the voltage drop between the collector and emitter of each IGBT be ΔU, the charging voltage of supercapacitors SC1 and SC2 be U1, and the series voltage of supercapacitors SC1 and SC2 be 2*U1. During the inverter process, the four IGBTs are turned on in pairs, and the voltage drop is 2*ΔU. After the inverter is turned on, the voltage is equal to the rated output voltage U0 of the diesel generator M, so U0 = 2*U1 - 2*ΔU.

[0036] Furthermore, the implementation method also includes the following steps:

[0037] Step 3, in-phase inversion;

[0038] Resistors R6 and R7 form a sampling voltage divider circuit. The output voltage U0 of the diesel generator M is divided by resistor R6, and the sampling voltage is applied across resistor R7. ; For sinusoidal alternating current signals, in Half a cycle, The diode D5 is connected to the non-inverting input of the comparator operational amplifier OP3. Negative half-cycle, It is connected to the inverting input of the comparator operational amplifier OP4 via diode D6;

[0039] The comparator operational amplifier OP1 and resistors R3 and R4 form a hysteresis comparator, and the comparator operational amplifier OP2 and capacitor C1 form an integrating circuit. The output of the hysteresis comparator is applied to the inverting input of the integrating circuit, and the output of the integrating circuit is fed back to the hysteresis comparator through resistor R1 as the reference voltage of the hysteresis comparator.

[0040] In the initial state of the circuit, the voltage across capacitor C1 is zero, the output Vo1 of the hysteresis comparator is high, capacitor C1 is charging, and the voltage at the output of the comparator op-amp OP2 is... Decreasing according to a linear law, when When the voltage drop causes the non-inverting input Vp of the comparator operational amplifier OP1 to be less than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes low.

[0041] After this, capacitor C1 begins to discharge, and the voltage at the output terminal of op-amp OP2 is compared. It rises according to a linear law, when When the rise of the voltage causes the non-inverting input Vp of the comparator OP1 to be greater than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes high.

[0042] This process repeats itself continuously, because The rising and falling times are equal, and the absolute values ​​of the slopes are also equal. It appears as a triangular wave; by adjusting the capacitance and resistance values, the amplitude and oscillation period of the triangular wave can be changed.

[0043] The potential at the non-inverting input of the hysteresis comparator is: Let Vom be the peak value of the triangular wave output, and Vz be the voltage of the Zener diode VDZ clamped to ground. When the triangular wave output... When the maximum value Vom is reached, there is The positive peak value of the triangular wave can be obtained. Positive peak value ;

[0044] During the transition from a negative peak value to a positive peak value in a triangular wave, the following are observed: Triangular wave oscillation period ;

[0045] Sample voltage and triangular wave voltage Connect the two compare inputs of comparator op-amps OP3 and OP4 respectively, and... Half a cycle, when When the output of the comparator OP3 is high, negative half-week, when When the output of the comparator OP4 is low, the positive and negative pulses with pulse widths that change proportionally with the amplitude of the sine wave are generated at the outputs of the comparator OP3 and the comparator OP4 through the superposition and comparison of the sine wave and the triangle wave.

[0046] Comparator op-amp OP5 and resistor R8 form an inverter to convert the low level output of comparator op-amp OP4 to the high level output of comparator op-amp OP5.

[0047] During the positive half-cycle of the sinusoidal waveform of the output voltage of the diesel generator M, IGBTs VT1 and VT4 are turned on by pulses that vary proportionally with the amplitude of the sinusoidal wave at voltage input terminal a, while IGBTs VT2 and VT3 are turned off at voltage input terminal b with no pulse output. During the negative half-cycle, IGBTs VT2 and VT3 are turned on by pulses that vary proportionally with the amplitude of the sinusoidal wave at voltage input terminal b, while IGBTs VT1 and VT4 are turned off.

[0048] Furthermore, the implementation method also includes the following steps:

[0049] Step 4, diesel generator M power follow;

[0050] When the diesel generator M's speed increases and its output voltage stabilizes at the rated value, the voltage monitoring sensor Q outputs, causing the relay coil KM-0 to engage. This opens the normally closed contacts KM-5, KM-6, and KM-7 of the relay, disconnecting supercapacitors SC1 and SC2 from the inverter circuit. The normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay close, connecting supercapacitors SC1 and SC2 in parallel. The output voltage of the diesel generator M then recharges supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB.

[0051] The present invention adopts the above technical solution and has the following technical effects compared with the prior art:

[0052] Two sets of supercapacitors are used as energy storage elements. When the diesel generator M is running normally, the two sets of supercapacitors are connected in parallel and in a low-voltage charging state. Their charging voltage is lower than the rated output voltage of the diesel generator M. When the electrical load of the diesel generator M suddenly increases, causing the instantaneous voltage drop to exceed the lower threshold, the two sets of supercapacitors become connected in series. Their series voltage is higher than the rated output voltage of the diesel generator M. After the excess voltage is reduced by the saturation voltage drop of the inverter IGBT element, the voltage value after inversion is basically the same as the rated output voltage of the diesel generator M. Through phase sampling and reproduction, the AC voltage output by the inverter and the AC voltage of the diesel generator M are superimposed in phase, which increases the instantaneous output power. The power increase is maintained for a few seconds. At the same time, the diesel generator M increases the power to meet the electrical load requirements after a few seconds through its own throttle adjustment. The voltage of the diesel generator M rises to the rated value, and the two sets of supercapacitors, after discharging, are reconnected in parallel and put into a charging state to prepare for the next discharge. This solves the problem of a significant drop in output voltage for a few seconds caused by the delayed throttle response of the diesel generator M due to a sudden increase in electrical load. When the electrical load of the diesel generator M suddenly increases, the inverter increases the instantaneous power by discharging the supercapacitor, reducing the voltage fluctuation time from 2 seconds to 0.2 seconds, and the voltage fluctuation amplitude is less than 1%. Attached Figure Description

[0053] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0054] Figure 1 The circuit diagram is for the control system of the present invention for improving the instantaneous power of a diesel generator. Detailed Implementation

[0055] Examples, such as Figure 1As shown, a control system for increasing the instantaneous power of a diesel generator includes supercapacitors SC1 and SC2. The positive terminal of supercapacitor SC1 is connected to one end of a normally open contact KM-1 and one end of a normally closed contact KM-6 of a relay. The negative terminal of supercapacitor SC1 is connected to one end of a normally closed contact KM-5 and one end of a normally open contact KM-2 of a relay. The positive terminal of supercapacitor SC2 is connected to one end of a normally open contact KM-3 and the other end of a normally closed contact KM-5 of a relay. The negative terminal of supercapacitor SC2 is connected to one end of a normally open contact KM-4 and one end of a normally closed contact KM-7 of a relay. The other ends of normally open contacts KM-1 and KM-3 are connected and connected to a rectifier voltage regulator TB. The other ends of normally open contacts KM-2 and KM-4 are connected and connected to a rectifier voltage regulator TB.

[0056] An inverter is connected to the other end of the normally closed contact KM-6 and the other end of the normally closed contact KM-7 of the relay. The inverter includes IGBT transistors VT1, VT2, VT3, and VT4. The collectors of IGBT transistors VT1 and VT2 are connected to the other end of the normally closed contact KM-6 of the relay. The emitters of IGBT transistors VT3 and VT4 are connected to the normally closed contact KM-7 of the relay. A rectifier regulator TB is connected to the emitters of IGBT transistors VT1 and VT3. The emitters of IGBT transistors VT2 and VT4 are grounded. A diode D1 is connected in parallel to the collector and emitter of IGBT transistor VT1, a diode D2 is connected in parallel to the collector and emitter of IGBT transistor VT2, a diode D3 is connected in parallel to the collector and emitter of IGBT transistor VT3, and a diode D4 is connected in parallel to the collector and emitter of IGBT transistor VT4.

[0057] The control system also includes a diesel generator M, one end of which is connected to a rectifier regulator TB and the other end is grounded. The control system also includes a voltage monitoring sensor Q, one of which is connected to the rectifier regulator TB and the other end is grounded. The output terminal of the voltage monitoring sensor Q is connected to one end of a relay coil KM-0 and the other end of the relay coil KM-0 is grounded. The control system also includes an electrical load W, one end of which is connected to the rectifier regulator TB and the other end is grounded.

[0058] The control system also includes a comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP5 is grounded. The inverting input of the comparator operational amplifier OP5 is connected to the output of the comparator operational amplifier OP4 and one end of a resistor R8. The other end of the resistor R8 is connected to the output of the comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP4 is connected to the inverting input of the comparator operational amplifier OP3, the output of the comparator operational amplifier OP2, one end of a resistor R1, and one end of a capacitor C1. The inverting input of the comparator operational amplifier OP4 is connected to one end of a diode D6. The non-inverting input of the comparator operational amplifier OP3 is connected to one end of a diode D5. The other ends of diode D5 and diode D6 are connected to one end of a resistor R6 and one end of a resistor R7. The other end of resistor R6 is connected to a voltage regulator, and the other end of resistor R7 is grounded.

[0059] The non-inverting input of the comparator op-amp OP2 is connected to one end of resistor R5, and the other end of resistor R5 is grounded. The inverting input of the comparator op-amp OP2 is connected to the other end of capacitor C1 and one end of resistor R4. The other end of resistor R4 is connected to one end of resistor R3 and one end of resistor R2. The other end of resistor R2 and the other end of resistor R1 are connected to the non-inverting input of the comparator op-amp OP1. The other end of resistor R3 is connected to the output of the comparator op-amp OP1. The inverting input of the comparator op-amp OP1 is grounded.

[0060] The gates of IGBT VT1 and IGBT VT4, and the output of comparator operational amplifier OP3 are voltage input point a, while the gates of IGBT VT2 and IGBT VT3, and the output of comparator operational amplifier OP5 are voltage input point b.

[0061] A method for implementing a control system to enhance the instantaneous power of a diesel generator includes the following steps:

[0062] Step 1: Supercapacitor stores electricity;

[0063] When the diesel generator M is in stable operating condition, its rated output voltage is U0. The output of the voltage monitoring sensor Q causes the coil of relay KM-0 to be energized, and the normally open contacts of relays KM-1, KM-2, KM-3, and KM-4 are closed. Supercapacitors SC1 and SC2 are connected in parallel. The output voltage of the diesel generator M charges supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB. The charging voltage is U1. Because there is voltage loss in the rectifier circuit, U1 is less than the rated output voltage U0 of the diesel generator M.

[0064] Let the charging circuit voltage be Vu, the internal resistance be R, the supercapacitor voltage be Vt, and the total capacitance of the supercapacitor be C. According to the capacitor charging formula... After a time t = R * C, the supercapacitor is fully charged. The internal resistance R of the charging circuit is approximately a few milliohms, and the total capacitance C is several thousand farads, so the charging time is approximately a few seconds.

[0065] Once the supercapacitor is fully charged, the rectifier regulator TB stops working.

[0066] Step 2, supercapacitor discharge;

[0067] When the electrical load W suddenly increases, the diesel generator M experiences a surge in instantaneous output current. This increases the resistance of the rotor magnet cutting magnetic lines of force, leading to a greater crankshaft load on the generator M and a decrease in its speed. Consequently, the output voltage and frequency drop. It is necessary to increase the throttle to boost the generator M's power and thus improve the output voltage and frequency. However, due to the lag in the adjustment response, it typically takes several seconds for the generator M's power to increase. Relying solely on the generator M's own adjustment inevitably results in a significant decrease in its output voltage and frequency during these few seconds, impacting the user's electrical equipment.

[0068] A voltage monitoring sensor Q is installed at the output terminal of the diesel generator M. When the electrical load suddenly increases, causing the diesel generator M to decrease its speed instantaneously, the voltage monitoring sensor Q detects that the output voltage has dropped to the threshold, and its output terminal stops outputting. The relay coil KM-0 is released, and the normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay open. Then, the normally closed contacts KM-5, KM-6, and KM-7 of the relay close, and the supercapacitors SC1 and SC2 are disconnected from the charging circuit, changing from parallel to series connection.

[0069] The inverter consists of IGBT transistors VT1, VT2, VT3, and VT4, which convert the DC power from supercapacitors SC1 and SC2 connected in series into AC power. Each IGBT transistor has a diode connected in parallel between its collector and emitter. When the inverter load is inductive, the diode can eliminate the reverse induced electromotive force and protect the IGBT transistor from being damaged by the reverse induced electromotive force.

[0070] IGBT VT1 and IGBT VT4 form the forward output circuit of the inverter, while IGBT VT2 and IGBT VT3 form the reverse output circuit. When the gates of IGBT VT1 and IGBT VT4 are connected to a forward voltage, and the gates of IGBT VT2 and IGBT VT3 are not connected to a forward voltage, IGBT VT1 and IGBT VT4 are turned on, while IGBT VT2 and IGBT VT3 are turned off. The inverter outputs forward, and the current flows out from the positive terminal of supercapacitor SC1, through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT1, the upper part of the electrical load W, the collector and emitter of IGBT VT4, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2 to form a circuit.

[0071] When the gates of IGBT VT2 and IGBT VT3 are connected to a positive voltage, and the gates of IGBT VT1 and IGBT VT4 are not connected to a positive voltage, IGBT VT2 and IGBT VT3 are turned on, while IGBT VT1 and IGBT VT4 are turned off. The inverter outputs in reverse, and the current flows out from the positive terminal of supercapacitor SC1, forming a circuit through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT2, the lower part of the electrical load W, the collector and emitter of VT3, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2.

[0072] In this way, by having the gates of IGBT VT1, IGBT VT4, IGBT VT2, and IGBT VT3 turned on in turn, the DC to AC inverter process can be realized.

[0073] Let the voltage drop between the collector and emitter of each IGBT be ΔU, the charging voltage of supercapacitors SC1 and SC2 be U1, and the series voltage of supercapacitors SC1 and SC2 be 2*U1. During the inverter process, the four IGBTs are turned on in pairs, and the voltage drop is 2*ΔU. After the inverter is turned on, the voltage is equal to the rated output voltage U0 of the diesel generator M, so U0 = 2*U1 - 2*ΔU.

[0074] △U is generally around 3V. Taking U0 as 220V as an example, U1 must be at least equal to 113V to ensure that the inverter voltage is not lower than 220V. In practical applications, the voltage of the supercapacitor will gradually decrease with the discharge time, and U1 is usually slightly higher than 113V, such as 115V.

[0075] Step 3, in-phase inversion;

[0076] To avoid overcurrent caused by the superposition of two AC power sources, it is necessary to perform M-phase sampling of the diesel generator and in-phase inversion of the supercapacitor.

[0077] Resistors R6 and R7 form a sampling voltage divider circuit. The output voltage U0 of the diesel generator M is divided by resistor R6, and the sampling voltage is applied across resistor R7. ; For sinusoidal alternating current signals, in Half a cycle, The diode D5 is connected to the non-inverting input of the comparator operational amplifier OP3. Negative half-cycle, It is connected to the inverting input of the comparator operational amplifier OP4 via diode D6.

[0078] The comparator op-amp OP1 and resistors R3 and R4 form a hysteresis comparator, and the comparator op-amp OP2 and capacitor C1 form an integrator circuit. The output of the hysteresis comparator is applied to the inverting input of the integrator circuit, and the output of the integrator circuit is fed back to the hysteresis comparator through resistor R1 as the reference voltage of the hysteresis comparator.

[0079] In the initial state of the circuit, the voltage across capacitor C1 is zero, the output Vo1 of the hysteresis comparator is high, capacitor C1 is charging, and the voltage at the output of the comparator op-amp OP2 is... Decreasing according to a linear law, when When the voltage drop causes the non-inverting input Vp of the comparator operational amplifier OP1 to be less than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes low.

[0080] After this, capacitor C1 begins to discharge, and the voltage at the output terminal of op-amp OP2 is compared. It rises according to a linear law, when When the rise of the voltage causes the non-inverting input Vp of the comparator OP1 to be greater than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes high.

[0081] This process repeats itself continuously, because The rising and falling times are equal, and the absolute values ​​of the slopes are also equal. It appears as a triangular wave; by adjusting the capacitance and resistance values, the amplitude and oscillation period of the triangular wave can be changed.

[0082] Because the potential at the non-inverting input of the hysteresis comparator is: Let Vom be the peak value of the triangular wave output, and Vz be the voltage of the Zener diode VDZ clamped to ground. When the triangular wave output... When the maximum value Vom is reached, there is The positive peak value of the triangular wave can be obtained. Positive peak value ;

[0083] Because a triangular wave undergoes a change from a negative peak value to a positive peak value, the following occurs: ;

[0084] Therefore, the triangular wave oscillation period ;

[0085] Sample voltage and triangular wave voltage Connect the two compare inputs of comparator op-amps OP3 and OP4 respectively, and... Half a cycle, when When the output of the comparator OP3 is high, negative half-week, when When the output of the comparator op-amp OP4 is low, the superposition and comparison of the sine wave and the triangle wave generate positive and negative pulses with pulse widths that change proportionally with the amplitude of the sine wave at the outputs of comparator op-amp OP3 and comparator op-amp OP4.

[0086] The comparator op-amp OP5 and resistor R8 form an inverter, which converts the low level of the output terminal of comparator op-amp OP4 to the high level of the output terminal of comparator op-amp OP5.

[0087] In this way, during the positive half-cycle of the sinusoidal waveform of the output voltage of the diesel generator M, voltage input terminal a is controlled by pulses that vary proportionally with the amplitude of the sinusoidal wave to turn on IGBTs VT1 and VT4, while voltage input terminal b has no pulse output and IGBTs VT2 and VT3 are turned off. During the negative half-cycle, voltage input terminal b is controlled by pulses that vary proportionally with the amplitude of the sinusoidal wave to turn on IGBTs VT2 and VT3, while IGBTs VT1 and VT4 are turned off. By operating in the above cycle, the AC power after the supercapacitor inverter and the AC power of the diesel generator M can be superimposed in phase, thereby improving the overall output power.

[0088] Step 4, diesel generator M power follow;

[0089] A few seconds later, the diesel generator M responds to the throttle and increases its speed. The output voltage stabilizes at the rated value. The voltage monitoring sensor Q outputs, causing the relay coil KM-0 to close. The normally closed contacts KM-5, KM-6, and KM-7 of the relay open, and the supercapacitors SC1 and SC2 disconnect from the inverter circuit. The normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay close, and the supercapacitors SC1 and SC2 are connected in parallel. The output voltage of the diesel generator M recharges the supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB.

[0090] The description of this invention is given for illustrative and descriptive purposes only and is not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A control system for increasing the instantaneous power of a diesel generator, characterized in that: It includes supercapacitors SC1 and SC2, which are connected to an inverter via normally closed contacts of a relay. The inverter includes four IGBT transistors. The control system also includes a diesel generator M, one end of which is connected to a rectifier regulator TB and the other end is grounded. The control system also includes a voltage monitoring sensor Q, one of which is connected to the rectifier regulator TB and the other end is grounded. The output of the voltage monitoring sensor Q is connected to one end of a relay coil KM-0 and the other end of the relay coil KM-0 is grounded. The control system also includes an electrical load W, one end of which is connected to the rectifier regulator TB and the other end is grounded. The positive terminal of the supercapacitor SC1 is connected to one end of the normally open contact KM-1 and one end of the normally closed contact KM-6 of the relay. The negative terminal of the supercapacitor SC1 is connected to one end of the normally closed contact KM-5 and one end of the normally open contact KM-2 of the relay. The positive terminal of the supercapacitor SC2 is connected to one end of the normally open contact KM-3 and the other end of the normally closed contact KM-5 of the relay. The negative terminal of the supercapacitor SC2 is connected to one end of the normally open contact KM-4 and one end of the normally closed contact KM-7 of the relay. The other end of the normally open contact KM-1 and the other end of the normally open contact KM-3 are connected to a rectifier and voltage regulator TB. The other end of the normally open contact KM-2 and the other end of the normally open contact KM-4 are connected to a rectifier and voltage regulator TB. An inverter is connected to the other end of the normally closed contact KM-6 and the other end of the normally closed contact KM-7 of the relay. The inverter includes IGBT transistors VT1, VT2, VT3 and VT4. The collectors of IGBT transistors VT1 and VT2 are connected to the other end of the normally closed contact KM-6 of the relay. The emitters of IGBT transistors VT3 and VT4 are connected to the other end of the normally closed contact KM-7 of the relay. A rectifier regulator TB is connected to the emitters of IGBT transistors VT1 and VT3. The emitters of IGBT transistors VT2 and VT4 are grounded. The collector and emitter of IGBT VT1 are connected in parallel with diode D1, the collector and emitter of IGBT VT2 are connected in parallel with diode D2, the collector and emitter of IGBT VT3 are connected in parallel with diode D3, and the collector and emitter of IGBT VT4 are connected in parallel with diode D4. The control system also includes a comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP5 is grounded. The inverting input of the comparator operational amplifier OP5 is connected to the output of the comparator operational amplifier OP4 and one end of a resistor R8. The other end of the resistor R8 is connected to the output of the comparator operational amplifier OP5. The non-inverting input of the comparator operational amplifier OP4 is connected to the inverting input of the comparator operational amplifier OP3, the output of the comparator operational amplifier OP2, one end of a resistor R1, and one end of a capacitor C1. The other end of the capacitor C1 is connected to the inverting input of the comparator operational amplifier OP2. The other end of the resistor R1 is connected to the non-inverting input of the comparator operational amplifier OP1. The inverting input of the comparator operational amplifier OP4 is connected to one end of a diode D6. The non-inverting input of the comparator operational amplifier OP3 is connected to one end of a diode D5. The other ends of diode D5 and diode D6 are connected to one end of a resistor R6 and one end of a resistor R7. The other end of the resistor R6 is connected to a rectifier regulator TB, and the other end of the resistor R7 is grounded. The non-inverting input of the comparator operational amplifier OP2 is connected to one end of resistor R5, and the other end of resistor R5 is grounded. The inverting input of the comparator operational amplifier OP2 is also connected to one end of resistor R4. The other end of resistor R4 is connected to one end of resistor R3 and one end of resistor R2. The other end of resistor R2 is connected to the non-inverting input of the comparator operational amplifier OP1. The other end of resistor R3 is connected to the output of the comparator operational amplifier OP1. The inverting input of the comparator operational amplifier OP1 is grounded. The gates of IGBT VT1 and VT4, and the output of comparator OP3 are voltage input terminal a. Voltage input terminal a is used to control the conduction of the inverter's forward output circuit, matching the positive half-cycle of the diesel generator's output voltage. The gates of IGBT VT2 and VT3, and the output of comparator OP5 are voltage input terminal b. Voltage input terminal b is used to control the conduction of the inverter's reverse output circuit, matching the negative half-cycle of the diesel generator's output voltage.

2. A method for implementing a control system to enhance the instantaneous power of a diesel generator, characterized in that: The implementation method is applied to the control system for increasing the instantaneous power of a diesel generator as described in claim 1, and includes the following steps: Step 1: Supercapacitor stores electricity; When the diesel generator M is in stable working condition, its rated output voltage is U0. The output of the voltage monitoring sensor Q causes the coil of relay KM-0 to be energized, and the normally open contacts of relays KM-1, KM-2, KM-3, and KM-4 are closed. Supercapacitors SC1 and SC2 are connected in parallel. The output voltage of the diesel generator M charges supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB. The charging voltage is U1. Because there is voltage loss in the rectifier circuit, U1 is less than the rated output voltage U0 of the diesel generator M. Let the charging circuit voltage be Vu, the internal resistance be R, the supercapacitor voltage be Vt, and the total capacitance of the supercapacitor be C. According to the capacitor charging formula... After time t=R*C, the supercapacitor is fully charged; Once the supercapacitor is fully charged, the rectifier and regulator TB stops working. The implementation method further includes the following steps: Step 2, supercapacitor discharge; The diesel generator M is equipped with a voltage monitoring sensor Q at its output terminal. When the electrical load suddenly increases, causing the diesel generator M to instantly decrease in speed, the voltage monitoring sensor Q detects that the output voltage has dropped to a threshold, and its output terminal stops outputting. The relay coil KM-0 is released, and the normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay are opened. Then, the normally closed contacts KM-5, KM-6, and KM-7 of the relay are closed, and the supercapacitors SC1 and SC2 are disconnected from the charging circuit, changing from parallel to series connection. The inverter converts the DC power from the series connection of supercapacitors SC1 and SC2 into AC power. Each IGBT transistor has a diode connected in parallel between its collector and emitter. When the inverter load is an inductive load, the diode can eliminate the reverse induced electromotive force and protect the IGBT transistor from being damaged by the reverse induced electromotive force. IGBT VT1 and IGBT VT4 form the inverter's forward output circuit, while IGBT VT2 and IGBT VT3 form the inverter's reverse output circuit. When the gates of IGBT VT1 and IGBT VT4 are connected to a forward voltage, and the gates of IGBT VT2 and IGBT VT3 are not connected to a forward voltage, IGBT VT1 and IGBT VT4 are turned on, while IGBT VT2 and IGBT VT3 are turned off, resulting in a forward output from the inverter. Current flows out from the positive terminal of supercapacitor SC1 and forms a circuit through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT1, the upper part of the electrical load W, the collector and emitter of IGBT VT4, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2. When the gates of IGBT VT2 and IGBT VT3 are connected to a positive voltage, while the gates of IGBT VT1 and IGBT VT4 are not connected to a positive voltage, IGBT VT2 and IGBT VT3 are turned on, and IGBT VT1 and IGBT VT4 are turned off. The inverter outputs in reverse, and the current flows out from the positive terminal of supercapacitor SC1, forming a circuit through the normally closed contact KM-6 of the relay, the collector and emitter of IGBT VT2, the lower part of the electrical load W, the collector and emitter of VT3, the normally closed contact KM-7 of the relay, and the negative terminal of supercapacitor SC2. By alternately turning on the gates of IGBT VT1, IGBT VT4, IGBT VT2, and IGBT VT3, the DC-to-AC inverter process can be achieved. Let the voltage drop between the collector and emitter of each IGBT be ΔU, the charging voltage of supercapacitors SC1 and SC2 be U1, and the series voltage of supercapacitors SC1 and SC2 be 2*U1. During the inverter process, the four IGBTs are turned on in pairs, and the voltage drop is 2*ΔU. After the inverter is turned on, the voltage is equal to the rated output voltage U0 of the diesel generator M, so U0 = 2*U1 - 2*ΔU.

3. The method for implementing a control system for increasing the instantaneous power of a diesel generator as described in claim 2, characterized in that: The implementation method further includes the following steps: Step 3, in-phase inversion; Resistors R6 and R7 form a sampling voltage divider circuit. The output voltage U0 of the diesel generator M is divided by resistor R6, and the sampling voltage is applied across resistor R7. ; For sinusoidal alternating current signals, in Half a cycle, The diode D5 is connected to the non-inverting input of the comparator operational amplifier OP3. Negative half-cycle, It is connected to the inverting input of the comparator operational amplifier OP4 via diode D6; The comparator operational amplifier OP1 and resistors R3 and R4 form a hysteresis comparator, and the comparator operational amplifier OP2 and capacitor C1 form an integrating circuit. The output of the hysteresis comparator is applied to the inverting input of the integrating circuit, and the output of the integrating circuit is fed back to the hysteresis comparator through resistor R1 as the reference voltage of the hysteresis comparator. In the initial state of the circuit, the voltage across capacitor C1 is zero, the output Vo1 of the hysteresis comparator is high, capacitor C1 is charging, and the voltage at the output of the comparator op-amp OP2 is... Decreasing according to a linear law, when When the voltage drop causes the non-inverting input Vp of the comparator operational amplifier OP1 to be less than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes low. After this, capacitor C1 begins to discharge, and the voltage at the output terminal of op-amp OP2 is compared. It rises according to a linear law, when When the rise of the voltage causes the non-inverting input Vp of the comparator OP1 to be greater than 0, the output of the hysteresis comparator jumps, and the output Vo1 of the hysteresis comparator becomes high. This process repeats itself continuously, because The rising and falling times are equal, and the absolute values ​​of the slopes are also equal. It appears as a triangular wave; by adjusting the capacitance and resistance values, the amplitude and oscillation period of the triangular wave can be changed. The potential at the non-inverting input of the hysteresis comparator is: Let Vom be the peak value of the triangular wave output. Compare the ground clamping voltage Vz between the output terminal of op-amp OP1 and the Zener diode connected in parallel to ground. When the triangular wave output... When the maximum value Vom is reached, there is The positive peak value of the triangular wave can be obtained. negative peak ; During the transition from a negative peak value to a positive peak value in a triangular wave, the following are observed: Triangular wave oscillation period ; Sample voltage and triangular wave voltage Connect the two compare inputs of comparator op-amps OP3 and OP4 respectively, and... Half a cycle, when When the output of the comparator OP3 is high, negative half-week, when When the output of the comparator OP4 is low, the positive and negative pulses with pulse widths that change proportionally with the amplitude of the sine wave are generated at the outputs of the comparator OP3 and the comparator OP4 through the superposition and comparison of the sine wave and the triangle wave. Comparator op-amp OP5 and resistor R8 form an inverter to convert the low level output of comparator op-amp OP4 to the high level output of comparator op-amp OP5. During the positive half-cycle of the sinusoidal waveform of the output voltage of the diesel generator M, IGBTs VT1 and VT4 are turned on by pulses that vary proportionally with the amplitude of the sinusoidal wave at voltage input terminal a, while IGBTs VT2 and VT3 are turned off at voltage input terminal b with no pulse output. During the negative half-cycle, IGBTs VT2 and VT3 are turned on by pulses that vary proportionally with the amplitude of the sinusoidal wave at voltage input terminal b, while IGBTs VT1 and VT4 are turned off.

4. The method for implementing a control system for increasing the instantaneous power of a diesel generator as described in claim 2, characterized in that: The implementation method further includes the following steps: Step 4, diesel generator M power follow; In step 3, the AC voltage output by the inverter and the AC voltage of the diesel generator M are superimposed in phase, increasing the instantaneous output power. After the power is increased, the speed of the diesel generator M increases, and the output voltage stabilizes at the rated value. The output of the voltage monitoring sensor Q causes the relay coil KM-0 to close, and the normally closed contacts KM-5, KM-6, and KM-7 of the relay open. The supercapacitors SC1 and SC2 are disconnected from the inverter circuit, and the normally open contacts KM-1, KM-2, KM-3, and KM-4 of the relay close. The supercapacitors SC1 and SC2 are connected in parallel, and the output voltage of the diesel generator M recharges the supercapacitors SC1 and SC2 through the rectifier and voltage regulator TB.

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