Automatic control system of electric pump rocket engine

Abstract

According to the automatic control system of the electric pump rocket engine, an electric pump closed-loop control framework is innovatively adopted, a traditional turbine pump and a traditional mechanical valve are replaced, and high-precision automatic adjustment of fuel parameters of a main propulsion system is achieved; the system comprises an electric pump, a pressure detection meter, a flow detection meter, a control module and a power supply module, in the system, a sensor continuously monitors the combustion chamber pressure and the pipeline fuel state; the control module calculates an error between a measured value and a target value through an algorithm to generate a PWM speed regulation signal, and the electric pump adjusts the rotating speed according to the signal to enable the combustion chamber pressure and the fuel flow to approach the target value; and when the error is smaller than the error allowable range, the output state is maintained, and precise thrust control and system closed-loop adjustment are achieved. The core innovation significance of the system is that an engine control system is subversively simplified, a fuel gas generator is omitted, hydraulic valves are reduced, the problems of slow response, complex structure and the like of a traditional scheme are solved, and a technical path is provided for simplifying the structure of a rocket engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aerospace propulsion technology, in particular to an automatic control system for a liquid rocket engine, and more particularly to a rocket engine control system based on an electric pump closed-loop control architecture. BACKGROUND

[0002] Traditional liquid rocket engines generally use a turbine pump as the core of the propellant supply system. The turbine pump is usually driven by high-temperature gas generated by a gas generator, and the flow and pressure of the propellant are adjusted through complex mechanical and hydraulic valves (such as pressure reducers and throttles). This technical solution has the following inherent defects: 1. Complex system: requires a gas generator, turbine, complex gas and liquid pipeline, and a large number of mechanical valves, resulting in an exceptionally complex engine structure, a large number of components, reliability challenges, and high manufacturing costs.

[0003] 2. Slow response: the turbine pump has a large moment of inertia, and the actuation speed of the mechanical valves is limited, resulting in slow response to control commands and difficulty in achieving rapid and precise adjustment of thrust.

[0004] 3. Limited control accuracy: the adjustment method relies on mechanical structures, which is easily affected by medium characteristics, wear and environmental factors, making it difficult to achieve high-precision steady-state control of combustion chamber pressure and fuel flow.

[0005] There are some improvement schemes in the prior art, for example: · CN116025485A (Carrying rocket attitude control power system based on electric pump) proposes an electric pump system for attitude control. However, this patent mainly applies to attitude control engines, which have completely different power levels, control targets and technical challenges from main propulsion systems. The attitude control system focuses on fast response and small thrust precise modulation, while the main propulsion system needs to handle large flow, high power and extremely high reliability requirements. This patent does not address the core problems faced by replacing the turbine pump with an electric pump in the main propulsion system.

[0006] · CN202211018754.0 (Combustion chamber air extraction circulating liquid rocket engine) simplifies the turbine drive source (directly extracts air from the combustion chamber), but its core is still the traditional turbine pump architecture, and it has not overcome the inherent limitations of large turbine inertia and slow response.

[0007] • Patents such as CN211176254U (MQL electrically controlled closed-loop precision adjustable micro pump) involve closed-loop control of electric pumps, but their application fields (industrial micro-lubrication), power levels (micro-amount), and technical indicators are vastly different from the requirements of the main propulsion system of a space rocket engine, and cannot be directly applied or provide effective technical inspiration.

[0008] Therefore, there is a lack of an all-electric, high-power, closed-loop control scheme in the prior art that can be applied to the main propulsion system of a rocket and fundamentally solve the problems of system complexity, response speed, and control accuracy. And China has made numerous breakthroughs in the field of new energy electric power, and the related industrial chain has developed and improved, making it possible for the electric power system to replace the traditional gas turbine and large-scale application. The present application takes advantage of China's unique new energy industry and provides a new technical path. SUMMARY

[0009] The purpose of the present application is to overcome the shortcomings of the prior art and provide an electric pump rocket engine automatic control system with simplified structure, rapid response, and high control accuracy, especially suitable for the main propulsion system.

[0010] The core innovation of the present application is that it completely abandons the traditional control architecture centered on turbine pumps and mechanical valves at the main propulsion system level, and innovatively uses a high-power electric pump as the core executive component, and builds a high-precision electrical closed-loop control strategy for the whole system, thereby fundamentally changing the system composition and working principle.

[0011] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: An electric pump rocket engine automatic control system, characterized by comprising: • Electric pump: as the core executive mechanism of the system, used to directly drive the fuel / oxidizer medium according to the electric control signal, and its speed can be steplessly and quickly adjusted; • Sensor group: including a pressure sensor for real-time monitoring of the combustion chamber pressure and a flow sensor for monitoring the fuel flow in the pipeline; • Control module: receiving real-time data collected by the sensor group, and comparing with the preset target pressure value and target flow value, calculating the error between the measured value and the target value through the built-in control algorithm, and then generating a pulse width modulation (PWM) speed signal; • Power module: providing high-power, stable power supply for the electric pump, sensor group, and control module.

[0012] The significant differences and creativity of the present application from the prior art mainly lie in: 1. Revolutionary simplification of architecture and fundamental difference in application field: • The invention: for the main propulsion system, a simple electrical closed loop of "sensor-controller-electric pump" is adopted, realizing the integration of "measurement-calculation-control", completely canceling the gas generator, turbine, and most of the hydraulic mechanical valves.

[0013] • Contrast CN116025485A: This patent is applied to the attitude control power system as an auxiliary and supplement to the main propulsion system. Its electric pump power is relatively small, and the control target is to realize the thruster switch and small amplitude adjustment, and it does not involve nor solve the core problem of canceling the main turbine pump. The invention is a complete reconstruction of the main propulsion system itself, which has far exceeded the former in terms of technical difficulty, innovation height and technical effect (simplifying the main system structure and reducing the overall weight).

[0014] • Contrast CN202211018754.0: Although this patent simplifies the source of turbine working medium, it still retains the core architecture of turbine, pump and mechanical valve, which belongs to the improvement of traditional technology. The invention completely cancels the turbine and is a revolutionary alternative.

[0015] 2. Fundamental change of control mechanism and outstanding improvement of performance: • The invention: by sending PWM electrical signals to the high-power electric pump, the rotational speed of the pump is directly and digitally controlled, thereby linearly and accurately controlling the fuel flow and post-pump pressure of the main propellant. This is a high-bandwidth, purely electrical direct drive method, with significantly reduced response delay, enabling millisecond-level thrust regulation.

[0016] • Contrast traditional turbine pump scheme: The traditional scheme indirectly controls the turbine speed by adjusting the fuel supply of the gas generator, or adjusts the flow by driving the valve opening degree through a mechanical servo mechanism. This is a low-bandwidth, indirect mechanical and hydraulic drive method, with obvious hysteresis and nonlinearity.

[0017] • Control accuracy: the closed-loop digital algorithm based on high-speed controller can achieve extremely high precision error elimination. When the system detects that the error is less than the allowed range, it maintains the current output state, thereby achieving sub-second thrust stability and ultra-high precision steady-state control. Advantages

[0018] In summary, the beneficial effects brought by the invention include: • The overall structure and control system of the main engine are greatly simplified, eliminating expensive gas generators, turbines, and complex mechanical valve systems, significantly reducing manufacturing costs, system dry weight, and failure rate.

[0019] • Achieved unprecedented fast response and high precision control of the main propulsion system, providing an excellent power solution for the rocket's precise orbit, thrust deep throttling, soft landing, deep space maneuvering and other tasks.

[0020] • Improved system reliability and testability, and the all-electric system is easier to test on the ground, fault diagnosis and health management.

[0021] • Provides a new and revolutionary technical path for the next generation of low-cost, high-reliability, reusable rocket engines. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The principle block diagram of the automatic control system of the electric pump rocket engine of the application. Figure 2 The physical diagram of the automatic control system of the electric pump rocket engine. DETAILED DESCRIPTION

[0023] The application will be described in detail below in conjunction with the drawings and examples.

[0024] System composition: the specific implementation of the system is shown in Figure 1 The electric pump is selected to withstand space environment, power level matching the demand of the main propulsion, high speed pump driven by brushless DC motor. The sensor is installed on the top of the thrust and the corresponding pipeline. The control module takes high-performance space-grade single-chip microcomputer as the core, and has built-in control algorithm. The power module uses lithium ion battery pack to provide stable and clean power.

[0025] Working process: after the system is powered on, the control module initializes and loads the preset target combustion chamber pressure P_target and target fuel flow Q_target. When the engine starts, the control module outputs the initial PWM signal to drive the electric pump to run at the set speed. Then, the pressure sensor and the flow sensor continuously collect the combustion chamber pressure P_actual and the fuel flow Q_actual, and feedback to the control module in real time.

[0026] Control algorithm in the control module (take python as an example, parameters for reference only): import datetime import os import time def control_electric_pump(operation_type): "Control electric pump" if operation_type == "reduce": pump_action = "Electric pump running" pump_power = "75%" elif operation_type == "increase": pump_action = "Electric pump running" pump_power = "80%" else: pump_action = "Electric pump in standby mode" pump_power = "0%" print(f"Electric pump: {pump_action} (Power: {pump_power})") return pump_action, pump_power def control_motor_speed(operation_type, current_value=None, target_value=None): """Control motor speed - Display speed based on current adjustment""" if operation_type == "decrease": # Calculate the rotational speed according to the required reduction degree. if current_value and target_value: adjustment_ratio = abs(current_value - target_value) / current_value motor_speed = int(1200 + adjustment_ratio * 300) # 1200-1500 RPM range else: motor_speed = 1350 # Default medium speed elif operation_type == "increase": # Calculate the rotational speed according to the required increase. if current_value and target_value: adjustment_ratio = abs(target_value - current_value) / current_value motor_speed = int(1000 + adjustment_ratio * 300) # 1000-1300RPM range else: motor_speed = 1150 # Default medium speed else: motor_speed = 0 print(f"Motor speed: {motor_speed} RPM") return motor_speed def save_data_to_file(original_data, processed_data, operation, min_val, max_val, pump_info, motor_info, filename="neural_data_log.txt"): """Save processed data to a file""" timestamp = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S") # Ensure the file exists if not os.path.exists(filename): with open(filename, 'w', encoding='utf-8') as f: f.write("=== Pressure Sensor Data Processing Log ===\n") f.write("Time\t\tOriginal Data\tProcessed Data\tOperation Type\tPump Status\tMotor Speed\tThreshold Range\n") f.write("-" * 120 + "\n") # Append data pump_action, pump_power = pump_info motor_speed = motor_info with open(filename, 'a', encoding='utf-8') as f: f.write(f"{timestamp}\t{original_data}\t\t{processed_data}\t\t{operation}\t\t{pump_action}({pump_power})\t{motor_speed}RPM\t[{min_val},{max_val}]\n") print(f"Data has been saved to {filename}") def process_neural_data(data, min_val=0.3, max_val=0.7, save_to_file=True, adjustment_step=0.02): """ Processing pressure sensor data - Slow linear adjustment version Includes a complete control process: judgment -> electric pump -> motor speed -> slow adjustment -> result saving. parameter: data: Input data value min_val: Lower threshold max_val: Upper limit threshold save_to_file: Whether to save to a file adjustment_step: The step size for each adjustment (default 0.02, i.e. 2%). return: Processed data """ original_data = data print(f"\nInput data: {data}") # Step 1: Determine the data range and the operation type if data > max_val: operation_type = "decrease" target_value = max_val # The goal is to adjust to the upper limit value print(f"Judgment: Data {data} is greater than the upper limit {max_val} -> needs to be slowly reduced to {target_value}") elif data <min_val: operation_type = "increase" target_value = min_val # The goal is to adjust to the lower limit value print(f"Judgment: Data {data} is less than the lower limit {min_val} -> needs to be slowly increased to {target_value}") else: operation_type = "Keep unchanged" target_value = data print(f"Judgment: If the data {data} is within the range [{min_val}, {max_val}] -> it remains unchanged") # Step Two: Controlling the Electric Pump pump_info = control_electric_pump(operation_type) # Step 3: Control the motor speed motor_info = control_motor_speed(operation_type, data, target_value) # Step 4: Slow Linear Adjustment Process if operation_type != "remain unchanged": print("Starting slow linear adjustment...") current_value = data step_count = 0 while abs(current_value - target_value)>0.001: # Precision control if operation_type == "decrease": # Slowly decrease if current_value>target_value: current_value = max(current_value - adjustment_step,target_value) else: break elif operation_type == "increase": # Slowly increase if current_value < target_value: current_value = min(current_value + adjustment_step, target_value) else: break step_count += 1 print(f" Step {step_count} adjustment: {current_value:.3f}") time.sleep(0.3) # 0.3 seconds interval between each adjustment, simulating a slow process # Prevent infinite loop, maximum of 50 adjustment steps if step_count >= 50: print(" Maximum adjustment steps reached, stopping adjustment") break result = current_value adjustment_amount = abs(result - original_data) adjustment_percent = (adjustment_amount / original_data) * 100 if original_data!= 0 else 0 operation = f"Slowly {operation_type} {adjustment_percent:.1f}% (total {step_count} steps)" print(f" Adjustment complete: {original_data} -> {result:.3f} (total adjustment {step_count} steps)") else: result = data operation = "Maintained unchanged" print(" No adjustment needed, keeping original value") # Step 5: Save data to file if save_to_file: save_data_to_file(original_data, result, operation, min_val, max_val, pump_info, motor_info) print(f"Final Result: {result:.3f}") return result def main(): """Main program - supports continuous processing""" print("=== Pressure Sensor Data Processing (Slow Linear Adjustment Version) ===") # Get threshold range and adjustment step (only need to set once) try: min_val = float(input("Enter lower threshold value (default 0.3): ") or "0.3") max_val = float(input("Enter upper threshold value (default 0.7): ") or "0.7") adjustment_step = float(input("Enter adjustment step (default 0.02, i.e., 2%): ")or "0.02") except ValueError: print("Using default settings: lower threshold 0.3, upper threshold 0.7, step 0.02") min_val, max_val, adjustment_step = 0.3, 0.7, 0.02 print(f"Threshold range set to: [{min_val}, {max_val}]") print(f"Adjustment step set to: {adjustment_step} ({adjustment_step*100:.1f}%)") print("-" * 50) while True: try: # Input data input_data = input("\nPlease enter pressure sensor data (between 0-1, enter 'q' to quit): ") if input_data.lower() == 'q': print("Program ended") break input_data = float(input_data) # Process data result = process_neural_data(input_data, min_val, max_val,adjustment_step=adjustment_step) print("Data prepared for next detection") print("-" * 50) except ValueError: print("Please enter a valid number or 'q' to exit") except KeyboardInterrupt: print("\nProgram interrupted by user") break def batch_process(): """Batch processing of neural network data - slow linear adjustment version""" print("=== Batch Neural Network Data Processing (Slow Linear Adjustment Version) ===") # Example neural network sensory data data_list = [0.1, 0.4, 0.8, 0.2, 0.9, 0.5, 0.6] min_val = 0.3 max_val = 0.7 adjustment_step = 0.02 # Default step size for batch processing print(f"Input data: {data_list}") print(f"Threshold range: [{min_val}, {max_val}]") print(f"Adjustment step: {adjustment_step} ({adjustment_step*100:.1f}%)") print("\nProcessing process:") results = [] for i, data in enumerate(data_list, 1): print(f"\n--- Processing the {i}th data---") result = process_neural_data(data, min_val, max_val, adjustment_step=adjustment_step) results.append(round(result, 3)) print(f"\n=== Batch processing complete===") print(f"Original data: {data_list}") print(f"Processing results: {results}") print("All data is ready for the next test") return results if __name__ == "__main__": print("=== Pressure sensor data system===") print("Select running mode:") print("1. Single data processing") print("2. Batch Data Processing") mode = input("Please select mode (1 / 2): ") if mode == '1': main() elif mode == '2': batch_process() else: print("Invalid selection, default to running single data processing") main() Error calculation. Based on the error value, the algorithm adjusts the duty cycle of the output PWM signal in real time, thereby changing the motor speed of the electric pump. Increasing or decreasing the electric pump speed directly leads to changes in fuel flow and downstream pressure, thus regulating the combustion chamber pressure.

[0027] This process is repeated continuously, forming a high dynamic closed-loop control, so that P_actual quickly approaches P_target. When the error value is less than the system set range, the control module maintains the current PWM output, the system enters the steady-state holding mode, and the precise stable control of the thrust is realized.

[0028] The difference with the comparative patent is as follows: Compared with CN116025485A, the embodiment has the following characteristics: 1. Power level: The power, flow rate and pressure parameters of the electric pump in the embodiment are designed according to the demand of the main propulsion engine, which are much higher than those of the attitude control system.

[0029] 2. Control target: The core of the embodiment is to maintain the steady-state work of the thrust chamber and large-scale throttling, rather than the pulse type on-off work of the attitude control engine.

[0030] 3. System integration: The embodiment is the core power unit of the main propulsion system, rather than an auxiliary system parallel to the main engine.

[0031] The present application is not limited to the specific technical details disclosed in the foregoing exemplary embodiments. Other specific structural forms can be realized without departing from the spirit or essential characteristics of the present application. Therefore, the described embodiments should be understood as exemplary rather than limiting. The actual protection scope of the present application is not limited by the description of the specific embodiments, but should be defined by the appended claims and their legal equivalents. Any modifications and changes within the scope of the claims should be included in the protection of the present application.

Claims

1. An automatic control system for an electrically pumped rocket engine, characterized in that The system comprises: An electric pump (1) connected to a fuel supply pipeline; a pressure detector (2) for real-time monitoring of the combustion chamber pressure; a flow detector (3) for real-time monitoring of the fuel pipeline flow; A control module (4) for receiving pressure and flow detection data and generating a PWM speed signal through a control algorithm; a power module (5) for powering the system; wherein the control module (4) realizes closed-loop control by comparing the error between the measured values of pressure / flow and the target values, dynamically adjusting the speed of the electric pump to make the parameters approach the target values, and maintaining a steady-state output when the error is less than the allowed threshold.

2. The system of claim 1, wherein: The control module (4) synchronously controls the combustion chamber pressure and the fuel flow, and the precision error of the double-parameter control is less than or equal to 1%; The system response delay is less than 10 ms, and the number of hydraulic valves is reduced.

3. The system of claim 1, wherein: The control module (4) pre-stores the thrust-pressure-flow dynamic mapping relationship (such as 100 kN thrust→5.2 MPa pressure+1.8 kg / s flow), supporting command adjustment.

4. The system of claim 1, wherein: The electric pump (1) is a motor-driven centrifugal pump.

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