Testing electronic controllers SAU GTE

The study of electronic control systems on the HIL test bench with feedback

Prior to mechanical and environmental testing HIL stand in a closed loop being tested electronic part of the control system to function in its entirety. Check software with real hardware for proper operation is performed under simulated interference, failures, failures of various types and degradation of system parameters.

Tests in a closed circuit can detect and eliminate many of the defects in the early stages of design before entering the expensive motor test stands and flight tests.

HIL bench for testing of electronic control systems in a closed circuit comprises a signal simulators sensors and actuators, personal computers with assistive software that can help keep the complex in different modes, and personal computers, which implemented a mathematical model of the engine and its hydro units operating in the real time. The study electronic system connected to the simulator of sensors and actuators.

The sensor simulators of the sensors convert digital input signals from a personal computer with a mathematical model of the motor into output signals identical in electrical parameters to signals from real sensors. The set of simulators corresponds to the number and types of sensors installed on the engine. For example, the simulator of a thermistor generates an equivalent resistance of the output signal circuit when a controlled current source is included in this circuit with a level proportional to the input code. The simulator consists of a register, a digital-to-analog converter, a current generator, a voltage former, a proportional current, a summing amplifier, and an ohmic divider.

Simulators actuators provide electrical load for the output circuit of the equivalent of the electrical parameters of the actual load, and generates a digital signal proportional to the control signal, which is input to a personal computer with a mathematical model of the engine.

Software booth

Simulators of each sensor and actuator are carried out in a separate board.

Software booth include:

- real-time models of the GTE and its hydromechanical units;

- software modules that ensure the operation of input-output devices, conversion and coding of signals;

- communication modules with a system timer for organizing the real-time mode;

- modules for displaying information in the form of graphs and tables in real time;

- modules providing a task for issuing and receiving test signals in the step-by-step program execution mode;

- programs for controlling devices of a semi-full-scale stand, etc.

During the tests on the HIL stands investigated collaboration of hardware and software on the transient and steady-state modes. To ensure sustainability and the required quality control over the entire range of flight conditions specified basic settings of digital controllers, practiced algorithms embedded control system and checked the logic parry bounce. In addition, testing is conducted integral hardware and software.

Investigation of the effect of electric influences

On the electronic controls GTE impact available on board the various electronic devices, branched communication line, powerful sources of energy, as well as external sources of electromagnetic interference (radar stations, high-voltage power lines, lightning strikes, etc.). In connection with this it is necessary to comprehensively investigate the immunity system in the laboratory before testing on an engine stand and flying laboratories.

To do this, the system shall be tested for certain types of influences: electromagnetic compatibility; the secondary effects of lightning discharges; instability of the onboard power supply and so on. d. Critical situations during flight may occur when the combined action of a number of factors. For example, lightning besides direct impact on the electronic control unit and the communication line

may cause substantial deviations in the on-board network and thereby further influence the electronic operation controller.

In carrying out such tests of electronic engine management systems effective is the use of automated complex consisting of imitators secondary effects of the lightning discharge, the instability of the onboard power supply, means of interference simulation and failures and hardware and software tools to simulate the electronic control systems in a closed circuit.

Study of electromagnetic compatibility of electronic engine management systems. Electromagnetic compatibility tests of electronic control systems include the study of electromagnetic interference generated by the system, and the susceptibility to electromagnetic interference from other on-board systems. EMC requirements of electronic systems installed, depending on the impacts of disturbances in their functioning.

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