Civil Unmanned Aircraft System Electrical Performance and EMC Test Plan

1. Plan Overview

This test plan provides an electrical performance and electromagnetic compatibility framework for civil UAV developers, manufacturers, and testing organizations, with emphasis on propulsion power systems, electrical safety, complete-aircraft emission and immunity, as well as ripple and system stability validation in high-risk scenarios.

1.1 Document Information

Prepared On The Basis Of	GB 42590-2023 Safety Requirements for Civil Unmanned Aircraft Systems
Applicable Scope	Civil unmanned aircraft systems: micro, light, and small categories
Document Version	V1.0
Document Type	Internal technical document

Referenced Standards

GB/T 38909-2020 Electromagnetic compatibility requirements and test methods for civil light and small UAV systems
GB 31241-2022, GB 38031-2020, and UN 38.3 for battery safety and transport requirements
IEC 61000-4-2 / -4-3 / -4-4 / -4-5 / -4-6 immunity standards
IEC 61000-3-2, CISPR 32, RTCA DO-160G, and MIL-STD-461G as references

1.2 Classification and Test Severity

Category	Empty Weight	Maximum Takeoff Weight	Typical Use	Test Severity
Micro	<0.25kg	-	Consumer entertainment	Basic
Light	≤4kg	≤7kg	Aerial photography, logistics	Standard
Small	≤15kg	≤25kg	Professional imaging, inspection	Enhanced

For high-risk applications such as flights over populated areas, critical infrastructure inspection, or missions in complex electromagnetic environments, it is recommended to raise immunity field strength, ripple levels, and retest margins beyond the baseline requirements.

Test Categories

The overall plan is organized into two main tracks: electrical performance testing for insulation, dielectric strength, leakage current, and battery protection, and EMC testing for radiated and conducted emissions, electrostatic discharge, RF immunity, surge, and conducted immunity, ensuring compatibility with civil aviation radar, communication systems, and surrounding electronics.

2. Complete-Aircraft Electrical Performance Test Plan

Complete-aircraft electrical performance testing focuses on insulation, protection against electric shock, battery protection, and thermal safety, forming the prerequisite baseline for all subsequent EMC and flight-condition verification.

2.1 Test Standard Framework

Level	Standard Source	Applicability
Basic standard	GB 4943.1-2022	Used for insulation, dielectric strength, leakage current, and related electrical safety items
Industry standard	GB/T 38909-2020	EMC requirements and methods for civil light and small UAV systems
Reference standard	IEC 62368-1	Safety of audio/video, information, and communication technology equipment
Aviation reference	RTCA DO-160G Section 16/20	Environmental and power-related verification for airborne electrical equipment

2.2 Test Item List

Item	Reference	Acceptance Requirement	Applicable Category
Insulation resistance	GB 4943.1-2022 5.2	Basic insulation ≥2MOhm	All categories
Dielectric strength	GB 4943.1-2022 5.2	No breakdown, no flashover	All categories
Leakage current	GB 4943.1-2022 5.1	Handheld equipment ≤0.25mA	All categories
Protective earth	GB 4943.1-2022 5.5	Ground resistance ≤0.1Ohm	Models with protective earth
Overcharge / short-circuit / overcurrent protection	GB 42590-2023 4.7	Charging stops or the circuit is cut off after protection triggers	All categories
Clearance and creepage distance	GB 4943.1-2022 5.2	Compliant with altitude correction requirements	All categories
Temperature rise	GB 4943.1-2022 4.5	Accessible parts temperature rise ≤75K	All categories

2.3 Key Test Methods

Item	Core Parameters	Key Criteria
Insulation resistance	DC 500V / 1000V, hold for 60s	Basic insulation ≥2MOhm, reinforced insulation ≥4MOhm
Dielectric strength	AC 1500V / 3000V, 60s	Leakage current ≤30mA, no breakdown or flashover
Leakage current	1.06 times rated voltage, measured with body simulation network	Handheld equipment ≤0.25mA
Protective earth	25A AC, 60s	Ground resistance ≤0.1Ohm

Insulation resistance should focus on the power terminals to enclosure path and between power terminals.
Dielectric strength testing should be performed with the sample disconnected from the power source and external loads, using a gradual ramp of 500V/s to 1000V/s.
Leakage current testing is recommended under normal operating conditions and should cover accessible metal parts and ungrounded enclosure surfaces.

2.4 Implementation Notes

Pre-check: Samples should be in final production hardware and software status, with batteries fully charged and preheated at room temperature for at least 30 minutes.
Fixture requirements: Insulation and dielectric strength items should be performed on a non-conductive bench, and fixtures should not introduce extra leakage paths.
Battery protection verification: Overcharge, short-circuit, and overcurrent items should be correlated with BMS protection logs to confirm trigger thresholds, response time, and recovery conditions.
Temperature rise verification: It is recommended to cover high-thermal states such as hover, takeoff, full-power flight, and charging, with hotspot mapping by thermal imaging.

3. Complete-Aircraft EMC Test Plan

According to Clause 4.12 of GB 42590-2023 and GB/T 38909-2020, complete-aircraft EMC verification includes EMI emissions, EMS immunity, and functional performance criteria under different flight states.

3.1 EMC Requirement Summary

Requirement	Specific Target	Reference
Radiated emission	Limits shall comply with GB/T 38909-2020	GB/T 38909-2020
RF immunity	Performance criterion shall be no lower than Class B	GB/T 38909-2020
Electrostatic discharge	Contact discharge ±8kV, air discharge ±15kV	IEC 61000-4-2
Equipment compatibility	Compatibility with civil aviation radar and related systems shall be ensured	GB/T 38909-2020

3.2 EMI Emission Tests

Test Item	Standard	Frequency Range	Key Requirement
Conducted emission at power ports	CISPR 32 / GB/T 38909-2020	150kHz-30MHz	Quasi-peak and average limits
Conducted emission at telecom ports	CISPR 32	150kHz-30MHz	Evaluated by port classification
Radiated emission	GB/T 38909-2020	30MHz-1GHz / 1GHz-6GHz	10m method preferred, 3m method when needed
Harmonic current	IEC 61000-3-2	Equipment with input current ≤16A	Evaluated by equipment class limits

Radiated emission testing is recommended in a fully anechoic chamber or semi-anechoic chamber, with 360-degree turntable rotation and antenna height scanning from 1m to 4m.
The aircraft should be operated in representative conditions such as hovering, takeoff, and landing to capture compound disturbances from motors, ESCs, and communication modules.

3.3 EMS Immunity Tests

Item	Standard	Level or Test Value	Performance Criterion
ESD	IEC 61000-4-2	Contact ±8kV, air ±15kV, at least 10 shots per polarity	Class B
Radiated immunity RS	IEC 61000-4-3	80MHz-6GHz, 3V/m or 10V/m	Class B
EFT	IEC 61000-4-4	±0.5kV to ±2kV, at least 1 minute per polarity	Class B
Surge	IEC 61000-4-5	Line-to-ground 0.5kV-4kV, line-to-line 0.5kV-2kV	Class B
CS	IEC 61000-4-6	150kHz-80MHz, 3V or 10V	Class B

3.4 Performance Criteria

Class	Description	Judgment Principle
Class A	Normal operation	No functional degradation during or after the test
Class B	Temporary degradation or loss	Recovers automatically after the test without user intervention
Class C	Recovery requires intervention	Operator action or system reset is required
Class D	Permanent damage	Damage or permanent loss of function with no recovery

GB 42590-2023 requires RF immunity performance not lower than Class B. Therefore, phenomena such as flight controller restart or loss of communication link with no self-recovery should be judged as non-compliant.

Typical Conducted Emission Test Configuration
UAV under test -> LISN -> Ground reference plane
Measuring receiver / spectrum analyzer

4. Test Plans for Major Subsystems

Key subsystems should be verified in three dimensions at the same time: performance, safety, and EMC. This avoids a situation where the complete aircraft passes but a critical module fails under complex operating conditions.

4.1 Battery System

Category	Test Items	Key Acceptance
Performance	Room-temperature capacity, low-temperature capacity, high-temperature capacity, charge retention, cycle life, internal resistance	Capacity and life shall meet rated targets
Safety	Overcharge, short circuit, overcurrent, crush, nail penetration, temperature cycling, vibration, shock, low pressure	No fire, no explosion, effective protection action
Method highlights	External short-circuit resistance ≤5mOhm; overcharge follows maximum continuous charge current	Enclosure temperature ≤150degC

Crush testing is recommended across 100kN to 200kN, holding for 10 minutes or until cell voltage drops to 0.5V.
Cycle-life testing should record capacity fade, internal resistance growth, and protection consistency.

4.2 Motor and ESC System

Test Direction	Main Items	Requirement
Electrical performance	Insulation resistance, dielectric strength, temperature rise, efficiency, speed characteristics	Stator-to-enclosure insulation ≥1MOhm, no breakdown, temperature rise within insulation class limits
EMC emission	Conducted emission, radiated emission	Comply with CISPR 32 Class B
EMC immunity	Radiated immunity	80MHz-6GHz, Class B

Operating states should include rated speed, typical PWM drive of the ESC, and stationary hover simulation under high-ripple conditions.

4.3 Flight Control System

ESD: contact ±8kV, air ±15kV.
RS: 3V/m, 80MHz-6GHz.
CS: 3V, 150kHz-80MHz.
EFT: signal ports ±1kV.
Signal integrity: IMU sampling rate ≥200Hz, command latency ≤50ms, CAN eye height ≥300mV.

4.4 Communication System

Operating bands shall comply with national radio regulations.
Maximum transmit power is generally limited to 100mW.
Frequency tolerance should be within ±50ppm and power tolerance within ±2dB.
Conducted and radiated emission, ESD, RS, and CS shall all meet the corresponding standard requirements.

4.5 Charging System

Input power shall not exceed rating, and output voltage/current accuracy should be within ±5%.
Charging efficiency is recommended at ≥85%, with ripple peak-to-peak not exceeding 1%.
EMC coverage should include conducted and radiated emission, harmonics, voltage fluctuation, ESD, EFT, surge, and RS.

4.6 GPS and Navigation Module

EMC: ESD, RS, CS, and conducted/radiated emission should be evaluated to Class B or 3V-level requirements as applicable.
Performance: horizontal positioning accuracy ≤10m CEP, vertical positioning accuracy ≤15m CEP.
Sensitivity: cold start ≥-148dBm, hot start ≥-156dBm.
Anti-jamming threshold is recommended at ≥-125dBm.

4.7 Sensor System

IMU, barometer, magnetometer, and related sensors should meet ESD, RS, CS, and radiated emission requirements.
IMU verification should focus on bias stability, noise density, and temperature drift.
Barometer accuracy is recommended at ±1hPa, and magnetometer heading accuracy at ±5deg.

4.8 Integration Principles for Subsystems

Proceed step by step from component, to module, to complete aircraft.
Subsystem test states should be as close as possible to actual flight power supply, thermal environment, and harness layout.
Common-mode interference paths among communication, navigation, and flight control subsystems should receive special attention.

5. Ripple Injection and Ripple Measurement

Ripple testing is used to verify the stability of the UAV power system under PWM switching, motor load fluctuation, and external supply disturbances. It is an important supplementary verification for flight control reliability and sensor anti-interference capability.

5.1 Ripple Injection Levels

Level	Ripple Peak-to-Peak	Application Scenario	Description
L1	≤100mV	Stable power environment	Indoor test environment
L2	≤200mV	General outdoor environment	Routine flight environment
L3	≤500mV	Complex electromagnetic environment	Near power facilities or communication base stations
L4	≤1V	Extreme electromagnetic environment	Special mission scenarios

GB/T 38909-2020 recommends that ripple at the main power port should not exceed 1% of rated voltage, while sensor supply ports should remain below 50mV and communication supply ports below 100mV.

5.2 Signal Parameters and Measurement Requirements

Item	Technical Requirement
Injection frequency range	10Hz-10MHz
Typical switching frequency	100kHz-500kHz
Waveform	Sine, square, or composite waveforms, AC superimposed on DC
Oscilloscope bandwidth	≥50MHz, and ≥200MHz recommended
Sampling rate	≥250MS/s
Measurement mode	AC coupling, peak-to-peak and RMS measurement

Ripple Injection Test Configuration
Ripple signal generator
Injection at battery port
Injection at sensor supply port
Injection at communication supply port
UAV system

5.3 Ripple Testing in Flight States

Scenario	Test Condition	Focus
Takeoff	Motor accelerates from 0 to 50% speed	Power ripple change and transient response
Hover	Motor runs steadily	Steady-state ripple and IMU data stability
High-speed flight	Full-speed, high motor RPM	Peak ripple and link stability
Landing	Motor decelerates to hover	Ripple recovery and control stability

5.4 Charging and Special-Environment Ripple Tests

Scenario	Test Condition	Purpose
Slow charge / fast charge / trickle	0.1C-1C	Verify charging ripple and BMS protection behavior
Charge while flying	Externally powered flight	Verify dynamic ripple coupling effects
High altitude	≤75kPa	Verify insulation and discharge characteristics
High temperature / low temperature / strong magnetic field	+55degC / -20degC / 30A/m	Verify power behavior and anti-interference capability

6. Recommended Test Equipment and Environment

A complete laboratory setup covering electrical safety, EMC, and flight-level integration is recommended, avoiding fragmented verification and poor reproducibility caused by disconnected test setups.

6.1 Key Test Equipment

Category	Equipment	Key Parameters
Electrical performance	Insulation resistance tester	DC 500V / 1000V, accuracy ±3%
Electrical performance	Hipot tester	AC 5kV / 100mA, adjustable ramp rate
Electrical performance	Leakage current tester	0.01mA-20mA, compliant with IEC 60990
Electrical performance	Digital oscilloscope	Bandwidth ≥200MHz, sampling rate ≥1GS/s
EMC	EMI receiver / spectrum analyzer	9kHz-44GHz
EMC	LISN, ESD simulator, EFT / surge combination tester	Compliant with CISPR 16 and IEC 61000-4 series
Flight integration	RTK differential GPS, attitude measurement system, link analyzer	Centimeter-level positioning and 0.1-degree attitude accuracy

6.2 Environmental Requirements

Parameter	Requirement	Description
Temperature	15degC-35degC	Variation ≤5degC/h
Relative humidity	25%RH-75%RH	Non-condensing
Atmospheric pressure	86kPa-106kPa	Standard atmospheric range
Vibration	No significant vibration source	Vibration acceleration ≤0.1g
Noise	≤60dB(A)	Suitable for audible observation during tests

Recommendations for EMC Chambers

Fully anechoic chambers are recommended to provide shielding effectiveness of at least 100dB and field uniformity within ±6dB.
Semi-anechoic chambers are recommended to provide shielding effectiveness of at least 80dB and are suitable for CISPR 32 and IEC 61000-4-3.
The 10m method should be preferred for radiated emission, with the 3m method used as a supplement when necessary.

Sample Status Confirmation

It is recommended to prepare at least two samples per test round, record final production software versions and hardware changes, fully charge batteries to rated capacity, keep the system powered on at room temperature for at least 30 minutes, and verify that nameplate markings match the specification.

7. Test Flow and Acceptance Rules

The recommended test flow begins with sample confirmation, technical document review, and equipment calibration, followed by electrical performance verification, then EMI, EMS, and ripple testing, and finally overall judgment and corrective retest.

Pre-test Preparation
Sample status confirmation -> Technical document review -> Test equipment calibration -> Environment confirmation
Electrical Performance Tests
Insulation resistance -> Dielectric strength -> Leakage current -> Ground test -> Battery tests
EMC Tests
EMI emission -> EMS immunity -> Ripple tests
Conducted emission -> Radiated emission -> ESD -> RS -> EFT -> Surge -> CS
Result Judgment
All items pass -> Issue qualification report
Non-compliant items -> Corrective action and retest -> Re-judgment

7.1 Acceptance Rules

Test Category	Acceptance Requirement
Electrical performance	All items must pass with zero tolerance
EMI emission	Compliance with limits constitutes pass
EMS immunity	Performance criterion no lower than Class B constitutes pass
Ripple tests	Pass if ripple remains within limits and function stays normal

7.2 Handling of Nonconformities

Situation	Handling Method
Single failure item	Corrective action and retest are allowed, with no more than two correction rounds
Two or more failed items	Judged as non-compliant, followed by redesign or full retest after correction
Critical safety item failure	Directly judged as non-compliant with no corrective retest allowed
Failure after retest	Terminate the test campaign and recommend redesign

8. Conclusion and Reference Notes

This plan is centered on Clause 4.7 for propulsion energy systems and Clause 4.12 for electromagnetic compatibility in GB 42590-2023, while incorporating practical experience from consumer electronics, automotive electronics, and airborne electronics testing to form a complete UAV electrical performance and EMC verification framework across the aircraft, key subsystems, and flight operating conditions.

At the complete-aircraft level, the focus is on insulation, dielectric strength, leakage current, battery protection, and EMC judgment closure.
At the subsystem level, the focus is on batteries, motor and ESC assemblies, flight control, communication, navigation, charging, and sensor reliability.
At the operating-condition level, the focus is on takeoff, hover, high-speed flight, charging, and ripple or immunity performance under extreme environments.
For execution, formal type verification and corrective retest are recommended with laboratories holding CNAS or CMA qualifications.

In addition to GB 42590-2023 and GB/T 38909-2020, referenced standards include GB 4943.1-2022, GB 31241-2022, GB 38031-2020, UN 38.3, the IEC 61000-4 series, IEC 61000-3-2, IEC 61000-3-3, CISPR 32, RTCA DO-160G, and MIL-STD-461G.

Technical basis: organized from the user-provided document Civil Unmanned Aircraft System Electrical Performance and EMC Test Plan